bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of environment and mid‐domain effect on moth species richness along a tropical elevational gradient
Authors: Brehm Gunnar , Colwell Robert K. , Kluge Jürgen
Published: December 2006

Aim  The biodiversity of geometrid moths (Lepidoptera) along a complete tropical elevational gradient was studied for the first time. The patterns are described, and the role of geometric constraints and environmental factors is explored.

Location  The study was carried out along the Barva Transect (10° N, 84° W), a complete elevational gradient ranging from 40 to 2730 m a.s.l. in Braulio Carrillo National Park, Costa Rica, and adjacent areas.

Methods  Moths were sampled manually in 2003 and 2004 at 12 rain forest sites using light ‘towers’, each with two 15 W ultraviolet fluorescent tubes. We used abundance‐based rarefaction, statistical estimation of true richness (Chao 1), geographically interpolated observed richness and Fisher's alpha as measures of local diversity.

Results   A total of 13,765 specimens representing 739 species were analysed. All four measures showed a hump‐shaped pattern with maxima between 500 and 2100 m elevation. The two subfamilies showed richness and diversity maxima at either lower (Ennominae) or higher (Larentiinae) elevation than Geometridae as a whole. Among the four environmental factors tested, relative humidity yielded the highest correlation over the transect with the rarefaction‐based richness estimates as well as with estimated true species richness of Geometridae as a whole and of Larentiinae, while rainfall explained the greatest variation of Ennominae richness. The elevational pattern of moth richness was discordant with both temperature and with tree species richness. A combination of all environmental factors in a stepwise multiple regression produced high values of r2 in Geometridae. The potential effects of geometric constraints (mid‐domain effect, MDE) were investigated by comparing them with observed, interpolated richness. Overall, models fitted very well for Geometridae as a whole and for Ennominae, but less well for Larentiinae. Small‐ranged species showed stronger deviations from model predictions than large‐ranged species, and differed strikingly between the two subfamilies, suggesting that environmental factors play a more pronounced role for small‐ranged species. We hypothesize that small‐ranged species (at least of the Ennominae) may tend to be host specialists, whereas large‐ranged species tend to be polyphagous. Based on interpolated ranges, mean elevational range for these moths was larger with increasing elevation, in accordance with Rapoport's elevational rule, although sampling effects may have exaggerated this pattern. The underlying mechanism remains unknown because Rapoport's ‘rescue’ hypothesis could not explain the observed pattern.

Conclusions  The results clearly show that moth diversity shows a hump‐shaped pattern. However, remarkable variation exists with regard to taxon and range size. Both environmental and geometric factors are likely to contribute to the observed patterns.
Children and Work: A Review of Current Literature and Debates
Authors: Bourdillon Michael
Published: December 2006

Recent literature concerning work in the lives of children raises several contentious issues. This contribution starts with issues arising from conceptualizations of childhood: we need to understand the continuities between the various stages of childhood and the adult world, and see children as active agents in their own development. The article discusses discourse and terminology surrounding children's work; children's rights and their relationship with fundamental human rights; the relationship between work and school; and briefly the relationship between children's work and poverty. It questions whether discourse on ‘abolishing child labour’ works in the children's interests.
Migrants Encounter Migrants in the City: the Changing Context of ‘Home’ for Second‐Generation Greek‐American Return Migrants
Authors: CHRISTOU ANASTASIA , KING RUSSELL
Published: December 2006

This article looks at the ‘return’ migration of second‐generation Greek Americans to their parents’ homeland, Greece. It is based on interviews with, and written accounts supplied by, 40 participants in the research, all now living in the Athens region. The article addresses two main sets of questions. First, why do they relocate to Greece, what are they looking for, and how do they cope with difficulties and disappointments? Second, and more specifically, how do they react to the fact that Greece is no longer a homogenous hellenistic society, but has become in recent years a de facto multicultural one due to the presence of hundreds of thousands of immigrant workers and their families? Three hypotheses are proposed for this inter‐migrant encounter: returnees, shocked by the ‘new immigration’, view it negatively as upsetting the ‘pure Greek’ homeland they had hoped to find; returnees are more sympathetic because of their own families’ history as immigrants in multicultural America; and returnees differentiate themselves as ‘good’ migrants from Greece’s immigrants who are constructed as ‘bad’ migrants. Evidence from the migrants’ testimonies is found to support all three hypotheses; however, there is more support for the second one. In addition, a fourth outcome was voiced: that of discrimination against Greek Americans who are made to feel, in certain circumstances, outsiders by the ‘true’ Greeks. Suggestions are made for further comparative research.
Multicultural Crisis Communication: Towards a Social Constructionist Perspective
Authors: Falkheimer Jesper , Heide Mats
Published: December 2006

Crisis communication is a field dominated by case studies and is lacking of systematic knowledge and theoretical framework analysis. Functionalist and objectivist perspectives have dominated the field even though there are exceptions. This may be one reason why multicultural approaches to crisis communication, increasingly relevant in contemporary society, are very few and undeveloped. The aim in the article is to give a critical analysis of research that has been done on crisis communication as well as intercultural public relations and develop a different theoretical framework. We propose the use of ethnicity, focusing collective cultural identity as dynamic, relational and situational in crisis theory and practice. Ethnic differences seem to escalate during crises. Media use and access are also discussed. A Swedish survey shows, among other things, that people with a foreign background read mainstream newspapers more seldom than average Swedes, but that the access to Internet and mobile phones is very high. Based on a social constructionist epistemology, the article ends with four proposals for future research and practice in multicultural crisis communication: (1) audience‐orientation – focusing sense‐making, (2) a proactive and interactive approach – focusing dialogue, (3) a community‐focused approach – focusing a long‐range pre‐crisis perspective and, (4) an ethnicity‐approach towards intercultural communication.
Development of ethnic disparities in internalizing and externalizing problems from adolescence into young adulthood
Authors: Van Oort Floor V.A. , Joung Inez M.A. , Mackenbach Johan P. , Verhulst Frank C. , Bengi‐Arslan Leyla , Crijnen Alfons A.M. , Van Der Ende Jan
Published: December 2006

Background:  Little is known about changes in ethnic disparities in mental health during the development of adolescents into young adults. The aim of this study was to study the development of disparities in internalizing and externalizing problems between Dutch natives and Turkish migrant children from adolescence into adulthood.

Methods:  Turkish migrants (n = 217) and Dutch natives (n = 723) completed two comparable questionnaires about internalizing and externalizing problems: the Youth Self‐Report at age 11–18 and the (Young) Adult Self‐Report ten years later, at age 21–28. We used mixed linear regression models to model development of mental health problems and to test changes in disparities in mental health between Turkish migrants and Dutch natives.

Results:  Both in adolescence and in adulthood migrants reported more internalizing and externalizing problems than natives, most pronounced for internalizing problems. Disparities decreased from adolescence into adulthood for both internalizing problems (−52%, p < .0001) and externalizing problems (−67%, p = .01), independently of gender, age, country of birth of Turkish adolescents, and parental socio‐economic position. The favorable changes in the disparities over time were due to more favorable development among Turkish migrants than among natives.

Conclusions:  In this prospective study, ethnic disparities in internalizing and externalizing problems decreased as adolescents entered adulthood. Different explanations are discussed.
Decision making about mode of delivery among pregnant women who have previously had a caesarean section: a qualitative study
Authors: Moffat MA , Bell JS , Porter MA , Lawton S , Hundley V , Danielian P , Bhattacharya S
Published: December 2006

Objective  To explore prospectively women’s decision making regarding mode of delivery after a previous caesarean section.

Main outcome measures  The evolution of decision making, women’s participation in decision making, and factors affecting decision making.

Design and methods  A qualitative study using diaries, observations and semi‐structured interviews. Data were analysed thematically from both a longitudinal and a cross‐sectional perspective.

Setting  An antenatal unit in a large teaching hospital in Scotland and participants’ homes.

Sample  Twenty‐six women who had previously had a caesarean section for a nonrecurrent cause.

Results  Women were influenced by their own previous experiences and expectations, and the final decision on mode of delivery often developed during the course of the pregnancy. Most acknowledged that any decision was provisional and might change if circumstances necessitated. Despite a universal desire to be involved in the process, many women did not participate actively and were uncomfortable with having responsibility for decision making. Feelings about the amount and quality of the information received regarding delivery options varied greatly, with many women wishing for information to be tailored to their individual clinical circumstances and needs. In contrast to the impression created in the media, there was no evidence of clear preferences or strong demands for elective caesarean section.

Conclusion  Women who have had a previous caesarean section do not usually have firm ideas about mode of delivery. They look for targeted information and guidance from medical personnel based on their individual circumstances, and some are unhappy with the responsibility of deciding how to deliver in the current pregnancy.
The impact of improving outcomes guidance on surgical management of vulval squamous cell cancer in southwest England (1997–2002)
Authors: Falconer AD , Hirschowitz L , Weeks J , Murdoch J
Published: December 2006

Objective  The objective of this study was to assess the impact of reorganisation of gynaecological services in southwest England following adoption of regionally agreed evidence‐based guidelines and publication of the National Improving Outcomes Guidance in 1999.

Design  Prospective audit with cross‐checking against histological reports.

Setting  All 19 acute hospitals in the four Cancer Networks of southwest England.

Sample  All subjects with squamous or verrucous vulval cancer diagnosed between 1997 and 2002.

Method  A one‐page minimum data set proforma agreed by the South West Gynaecology Tumour Panel was completed by surgeons after treatment of each patient, and was sent to South West Cancer Intelligence Service for entry, collation and analysis. Data are presented for the years 1997 to 2002 inclusive, and comparisons were made between each of the three 2‐year cohorts.

Main outcome measures  These are standards derived from the guidance.

Results  There were 436 squamous or verrucous vulval cancers registered. Recording of staging was missing in 20% of subjects. The percentage of subjects operated upon by lead gynaecological cancer surgeons increased from 78% in cohort 1 to 93% in cohort 3 (P < 0.001). There is a trend towards more conservative operations, which have lower co‐morbidity. High activity surgeons achieved better rates of tumour‐free skin margins, but even these were adequate only in 49% of operations. Lymphadenectomy rates did not follow guidance.

Conclusion  Centralisation of care of this rare cancer should continue, but specialists need to increase their efforts to ensure adequate skin margins and lymphadenectomy rates while balancing morbidity and the likelihood of recurrence in both fit and frail patients.
Alcohol‐induced blood–brain barrier dysfunction is mediated via inositol 1,4,5‐triphosphate receptor (IP3R)‐gated intracellular calcium release
Authors: Haorah James , Knipe Bryan , Gorantla Santhi , Zheng Jialin , Persidsky Yuri
Published: December 2006

The blood–brain barrier (BBB) formed by brain microvascular endothelial cells (BMVEC), pericytes and astrocytes controls the transport of ions, peptides and leukocytes in and out of the brain. Tight junctions (TJ) composed of TJ proteins (occludin, claudins and zonula occludens) ensure the structural integrity of the BMVEC monolayer. Neuropathologic studies indicated that the BBB was impaired in alcohol abusers; however, the underlying mechanism of BBB dysfunction remains elusive. Using primary human BMVEC, we previously demonstrated that oxidative stress induced by ethanol (EtOH) metabolism in BMVEC activated myosin light chain kinase (MLCK), resulting in the enhanced phosphorylation of either cytoskeletal or TJ proteins, and in BBB impairment. We proposed that EtOH metabolites stimulated inositol 1,4,5‐triphosphate receptor (IP3R)‐operated intracellular calcium (Ca2+) release, thereby causing the activation of MLCK in BMVEC. Indeed, treatment of primary human BMVEC with EtOH or its metabolites resulted in the increased expression of IP3R protein and IP3R‐gated intracellular Ca2+ release. These functional changes paralleled MLCK activation, phosphorylation of cytoskeletal/TJ proteins, loss of BBB integrity, and enhanced leukocyte migration across BMVEC monolayers. Inhibition of either EtOH metabolism or IP3R activation prevented BBB impairment. These findings suggest that EtOH metabolites act as signaling molecules for the activation of MLCK via the stimulation of IP3R‐gated intracellular Ca2+ release in BMVEC. These putative events can lead to BBB dysfunction in the setting of alcoholism, and to neuro‐inflammatory disorders promoting leukocyte migration across the BBB.
Identification and characterization of microsatellite markers derived from expressed sequence tags (ESTs) of radish (Raphanus satvius L.)
Authors: WANG NING , HU JINGJIE , OHSAWA RYO , OHTA MASARU , FUJIMURA TATSUHITO
Published: December 2006

Radish, Raphanus satvius, is a very important commercial crop in the world, especially in East Asian countries. In this study, radish microsatellite markers have been developed for the first time from expressed sequence tags (ESTs). A total of 8 primer pairs were able to produce clear amplifications, respectively, which gave 2–5 polymorphic loci between 43 cultivars of Japanese radish. Observed and expected heterozygosity ranged from 0 to 0.4186, and from 0.1779 to 0.6205, respectively. Polymorphic information content ranged from 0.171 to 0.575. The eight simple sequence repeats were also polymorphic when tested by wild radish (Raphanus raphanistrum). Deviation from Hardy–Weinberg equilibrium was analysed in three populations, and no linkage disequilibrium was observed. It is anticipated that these newly developed microsatellite markers can advance further genomic analyses. This accomplishment may in turn accelerate and simplify radish breeding programs.
The development of eight microsatellite loci in the wild daffodilNarcissus triandrus(Amaryllidaceae)
Authors: HODGINS KATHRYN A. , STEHLIK IVANA , WANG PAULINE , BARRETT SPENCER C. H.
Published: December 2006

We report microsatellite primer pairs for the wild tristylous daffodil,Narcissus triandrus(Amaryllidaceae).From enriched libraries, we identified 58 unique microsatellite loci. We designed primer pairs for 27 of these loci and screened genomic DNA from 38 to 40 adults from a single population. For eight polymorphic loci, the number of alleles per locus ranged from five to 17. As six primers also amplified loci in three otherNarcissusspecies, including two horticultural varieties, we expect that some of these markers will be transferable to otherNarcissusspecies.
The highly polymorphic microsatellite markers for the greater long‐tailed hamster (Tscherskia triton)
Authors: XU LAIXIANG , SONG MINGJING , GUO YU , KONG FANHUA , ZHANG ZHIBIN
Published: December 2006

We isolated 25 dinucleotide microsatellite loci from the greater long‐tailed hamster (Tscherskia triton) populations in North China. We developed the amplification conditions of polymerase chain reaction for producing high‐resolution genetic markers for each locus. We found 10 microsatellite loci were highly polymorphic in 90 individual hamsters from three areas of North China, and the number of alleles in each locus varied from three to 11. These markers are potential tools for studying the genetic variation of the natural populations of this species.
Hospitalization of Nursing Home Residents: The Effects of States' Medicaid Payment and Bed‐Hold Policies
Authors: Intrator Orna , Grabowski David C. , Zinn Jacqueline , Schleinitz Mark , Feng Zhanlian , Miller Susan , Mor Vince
Published: December 2006

Objective. Hospitalizations of nursing home residents are costly and expose residents to iatrogenic disease and social and psychological harm. Economic constraints imposed by payers of care, predominantly Medicaid policies, are hypothesized to impact hospitalizations.

Data Sources/Study Setting. Federally mandated resident assessments were merged with Medicare claims and eligibility files to determine hospitalizations and death within 150 days of baseline assessment. Nursing home and market characteristics were obtained from the Online Survey Certification and Reporting, and the Area Resource File, respectively. States' average daily Medicaid nursing home payments and bed‐hold policies were obtained independently.

Study Design. Prospective cohort study of 570,614 older (≥65‐year‐old), non‐MCO (Medicare Managed Care), long‐stay (≥90 days) residents in 8,997 urban, freestanding nursing homes assessed between April and June 2000, using multilevel models to test the impact of state policies on hospitalizations controlling for resident, nursing home, and market characteristics.

Principal Findings. Overall, 99,379 (17.4 percent) residents were hospitalized with rates varying from 8.4 percent in Utah to 24.9 percent in Louisiana. Higher Medicaid per diem was associated with lower odds of hospitalizations (5 percent lower for each $10 above average $103.5, confidence intervals [CI] 0.91–0.99). Hospitalization odds were higher by 36 percent in states with bed‐hold policies (CI: 1.12–1.63).

Conclusions. State Medicaid bed‐hold policy and per‐diem payment have important implications for nursing home hospitalizations, which are predominantly financed by Medicare. This study emphasizes the importance of properly aligning state Medicaid and federal Medicare policies in regards to the subsidy of acute, maintenance, and preventive care in the nursing home setting.
Killing the Law of Large Numbers: Mortality Risk Premiums and the Sharpe Ratio
Authors: Milevsky M. A. , Promislow S. D. , Young V. R.
Published: December 2006

Abstract

We provide an overview of how the law of large numbers breaks down when pricing life‐contingent claims under stochastic as opposed to deterministic mortality (probability, hazard) rates. In a stylized situation, we derive the limiting per‐policy risk and show that it goes to a non‐zero constant. This is in contrast to the classical situation when the underlying mortality decrements are known with certainty, per policy risk goes to zero. We decompose the standard deviation per policy into systematic and non‐systematic components, akin to the analysis of individual stock (equity) risk in a Markowitz portfolio framework. Finally, we draw upon the financial analogy of the Sharpe Ratio to develop a premium pricing methodology under aggregate mortality risk.
Guns vs. Taxes? A Look at How Defense Spending Affects U.S. Federal Tax Policy
Authors: CARROLL DEBORAH A.
Published: December 2006

Although studies have shown a theoretical and empirical link between defense spending and economic growth and between economic growth and tax policy, the impact of defense spending on federal tax policy remains largely unexplored. This paper proposes a theoretical model and empirical test to explore the direct and indirect effects of defense spending on federal tax policy. The findings suggest that consumption expenditures for national defense directly influence the federal corporate income tax rate. However, the analysis finds no indirect relationship between defense spending and federal tax policy mediated through economic growth.
BOOK REVIEWS
Authors: Teitelbaum Michael S. , Courtney Damien
Published: December 2006

Books reviewed in this article:

Amartya SenIdentity and Violence: The Illusion of Destiny

Mary E. DalyThe Slow Failure: Population Decline and Independent Ireland, 1922‐1973
Chemical Constituents of Daphne giraldii Nitsche
Authors: Sun Wei‐Xin , Zhang Qiang , Jiang Jian‐Qin
Published: December 2006

In a search for structurally interesting substances from traditional Chinese medicines, eight compounds were isolated from an ethanolic extract of the stem bark of Daphne giraldii Nitsche. On the basis of one‐and two‐dimensional nuclear magnetic resonance and mass spectrometry data, and chemical methods, their structures were determined to be 2H‐1‐benzopyran‐2‐one‐8‐hydroxy‐7‐O‐β‐D‐glucopyranosyl‐5‐(2‐oxo‐2H‐1‐benzopyran‐7‐hydroxy‐8‐yloxy) (compound 1), 1‐pentanone, 1‐(4‐hydroxyphenyl)‐5‐phenyl (compound 2), octadecyl caffeate (compound 3), (+)syringaresinol‐4,4′‐diglycoside (compound 4), daphnetin‐8‐O‐β‐D‐glucopyranoside (compound 5), p‐hydroxybenzoic acid (compound 6), 7,7′‐dihydroxy‐[6, 8′‐bi‐2H‐benzopyran]‐2, 2′‐dione (compound 7), and daphnorin (compound 8), respectively. Of the compounds isolated, compounds 1 and 2, which we named daphnolin and daphnolon, respectively, were new, and the others were obtained from this plant for the first time.

(Managing editor: Wei Wang)
Cloning and Characterization of a Differentially Expressed Phenylalanine Ammonialyase Gene (IiPAL) After Genome Duplication from Tetraploid Isatis indigotica Fort.
Authors: Lu Bei‐Bei , Du Zhen , Ding Ru‐Xian , Zhang Lei , Yu Xiao‐Jing , Liu Cheng‐Hong , Chen Wan‐Sheng
Published: December 2006

Phenylpropanoid derivatives are a complex class of secondary metabolites that have many important roles in plants during normal growth and in responses to environmental stress. Phenylalanine ammonialyase (PAL) catalyzes the first step in the biosynthesis of phenylpropanoids. In the present study, we isolated a novel phenylalanine ammonialyase gene (designated as IiPAL) from tetraploid Isatis indigotica Fort. by rapid amplification of cDNA ends (RACE), which was a cultivar from the diploid plant by genome duplication. The full‐length cDNA of IiPAL was 2 530‐bp long with an open reading frame (ORF) of 2 178 bp encoding a polypeptide of 725 amino acid residues. Analysis of IiPAL genomic DNA revealed that it was structurally similar to other plant PAL genes, with a single intron at a conserved position, and a long highly conserved second exon. Semi‐quantitative RT‐PCR revealed that the IiPAL expression in roots and leaves from a tetraploid sample was higher than that in diploid progenitor, whereas expression of IiPAL in stems was almost the same as each other. Furthermore, the highest expression of IiPAL in tetraploid plant was found in roots, which was found in stems in diploid plants. Further expression analysis revealed that gibberellin (GA3), abscisic acid (ABA), methyl jasmonate (MeJA) and cold treatments could up‐regulate the IiPAL transcription in tetraploid plants. All our findings suggest that IiPAL participates not only in the defense/stress responsive pathways, but also probably in the polyploidy evolution of I. indigotica.

(Managing editor: Wei Wang)
Inheritance and Gene Mapping of Resistance to Soybean Mosaic Virus Strain SC14 in Soybean
Authors: Li Hai‐Chao , Zhi Hai‐Jian , Gai Jun‐Yi , Guo Dong‐Quan , Wang Yan‐Wei , Li Kai , Bai Li , Yang Hua
Published: December 2006

Soybean mosaic virus (SMV) is one of the most broadly distributed diseases worldwide. It causes severe yield loss and seed quality deficiency in soybean (Glycine max (L.) Merr.). SMV Strain SC14 isolated from Shanxi Province, China, was a newly identified virulent strain and can infect Kefeng No. 1, a source with wide spectrum resistance. In the present study, soybean accessions, PI96983, Qihuang No. 1 and Qihuang No. 22 were identified to be resistant (R) and Nannong 1138‐2, Pixianchadou susceptible (S) to SC14. Segregation analysis of PI96983 x Nannong 1138‐2 indicated that a single dominant gene (designated as RSC14) controlled the resistance to SC14 at both V2 and R1 developmental stages. The same results were obtained for the crosses of Qihuang No. 1 × Nannong 1138‐2 and Qihuang No. 22 × Nannong 1138‐2 as in PI96983 × Nannong 1138‐2 at V2 stage, but at R1 stage, the F1 performed as necrosis (a susceptible symptom other than mosaic), F2 segregated in a ratio of 1R:2N:1S, and the progenies of necrotic (N) F2 individuals segregated also in R, N and S. It indicated that a single gene (designated as RSC14Q, to be different from that of PI96983) controlled the resistance to SC14, its dominance was the same as in PI96983 × Nannong 1138‐2 (without symptoms) at V2 stage and not the same at R1 stage. The tightly linked co‐dominant simple sequence repeat (SSR) marker Satt334 indicated that all the heterozygous bands were completely corresponding to the necrotic F2 individuals, or all the necrotic F2 individuals were heterozygotes. It was inferred that necrosis might be due to the interaction among SMV strains, resistance genes, genetic background of the resistance genes, and plant development stage. Furthermore, the bulked segregant analysis (BSA) of SSR markers was conducted to map the resistance genes. In F2of PI96983 × Nannong 1138‐2, five SSR markers, Sat_297, Sat_234, Sat_154, Sct_033 and Sat_120, were found closely linked to RSC14, with genetic distances of 14.5 cM, 11.3cM, 4.3cM,3.2cM and 6cM, respectively. In F2 of Qihuang No. 1 × Nannong 1138‐2, three SSR markers, Sat_234, Satt334 and Sct_033, tightly linked to RSC14Q with genetic distances of 7.2 cM, 1.4 cM and 2.8 cM, respectively. Based on the integrated joint map by Cregan et al. (1999), both RScMand RSC14Q were located between Sat_234 and Sct_033 on linkage with group F of soybean, with their distances from Sct_033 at the same side being 3.2 cM and 2.8 cM, respectively. Therefore, RSC14and RSC14Q might be on a same locus. The obtained information provides a basic knowledge for marker‐assisted selection of the resistance gene in soybean breeding programs and fine mapping and map‐based cloning of the resistance gene.

(Managing editor: Li‐Hui Zhao)
Decrease of Photosystem II Photochemistry in Arabidopsis ppt1 Mutant Is Dependent on Leaf Age
Authors: Ma Jin‐Fang , Guo Jin‐Kui , Peng Lian‐Wei , Chen Cui‐Yun , Zhang Li‐Xin
Published: December 2006

In the present study, we compared the effect of leaf age at one development stage on the photosynthetic behavior of a T‐DNA‐tagged allele of the ppt1 mutant. Chlorophyll fluorescence (Fv/Fm, where Fm is the maximum fluorescence yield and Fv is variable fluorescence) and fluorescence decay kinetics of the ppt1 mutant were different in leaves of different ages. The steady state levels of thylakoid membrane proteins in 40‐day‐old leaves were decreased compared with those in 20‐day‐old leaves and changes in photosystem (PS) II proteins were correlated with those of the Fv/Fm ratio in the ppt1 mutant. Increased accumulation of leaf sugars was accompanied by decreased photosynthetic gene transcripts and protein content in 40‐day‐old leaves of the mutant. Thus, the results of the present study provide evidence for the phosphate translocator in maintaining normal photosynthesis at a late leaf age.

(Managing editor: Ping He)
Color Quality of Oregon Strawberries—Impact of Genotype, Composition, and Processing
Authors: Ngo T. , Wrolstad R.E. , Zhao Y.
Published: December 2006

ABSTRACT:  This investigation was to evaluate fruit color and study the effect of processing on color quality of strawberry products. Three color instruments with different viewing angles, viewing areas, and sample presentation geometries were compared for their effectiveness in measuring CIEL*C*ho color values for fresh fruits of 6 strawberry genotypes. There were significant differences between genotypes as well as between instruments. Fruits from the Totem genotype were frozen, canned, and made into jam. Color changes were measured along with the following compositional determinations: total monomeric anthocyanins (ACN), total phenolic content (TPC), and percent polymeric color. ACN in fresh strawberries ranged from 37.1mg to 122.3 mg per 100 g of fresh fruit. Freezing resulted in an apparent increase in ACN and transfer of 70.2% of the anthocyanins from the berries into juice. Physical transfer of pigments to syrup also occurred with canning: there was approximately 70% loss in ACN, about 20% increase in polymeric color, and 23.5% decrease in TPC. Pronounced color change and substantial losses in ACN and TPC of strawberry jams occurred during processing and 9 wk of storage. Storage of jams at 38 °C compared to 21 °C over a period of 9 wk resulted in marked losses of ACN and TPC.
Production of Conjugated Linoleic Acid‐Rich Potato Chips
Authors: Jain Vishal P. , Proctor Andrew
Published: December 2006

ABSTRACT:  Conjugated linoleic acid (CLA) is found primarily in diary and beef products, but the health benefits of CLA can only be realized if they are consumed at much greater levels than a normal healthy dietary intake. We have recently shown that a CLA‐rich soy oil can be produced by simple isomerization of linoleic acid in soy oil by photoirradiation. This oil may allow greatly increased dietary CLA without significantly elevating fat intake. The objective of this study was to prepare CLA‐rich potato chips by frying in CLA‐rich soy oil. Soy oil was photoisomerized in the presence of iodine catalyst with UV/visible light. The irradiated oil was clay processed to remove the residual iodine and this oil was then used to fry potato chips. Oil was extracted from fried chips and analyzed for its CLA content with gas chromatography. A 1‐oz serving of CLA‐rich potato chips contained approximately 2.4 g CLA as compared to 0.1 g CLA in 3‐oz serving of steak fillet and 0.06 g CLA in 8‐oz serving of whole milk. The peroxide value of the oil extracted from potato chips was found to be 1 meq/1000 g sample, which was within the acceptable commercial standards. This study may lead to the commercialization of CLA‐rich food products.
A Cellular Solid Model of the Lamina Cribrosa: Mechanical Dependence on Morphology
Authors: Sander E. A. , Downs J. C. , Hart R. T. , Burgoyne C. F. , Nauman E. A.
Published: December 2006

The biomechanics of the optic nerve head (ONH) may underlie many of the potential mechanisms that initiate the characteristic vision loss associated with primary open angle glaucoma. Therefore, it is important to characterize the physiological levels of stress and strain in the ONH and how they may change in relation to material properties, geometry, and microstructure of the tissue. An idealized, analytical microstructural model of the ONH load bearing tissues was developed based on an octagonal cellular solid that matched the porosity and pore area of morphological data from the lamina cribrosa (LC). A complex variable method for plane stress was applied to relate the geometrically dependent macroscale loads in the sclera to the microstructure of the LC, and the effect of different geometric parameters, including scleral canal eccentricity and laminar and scleral thickness, was examined. The transmission of macroscale load in the LC to the laminar microstructure resulted in stress amplifications between 2.8 and 24.5×IOP. The most important determinants of the LC strain were those properties pertaining to the sclera and included Young’s modulus, thickness, and scleral canal eccentricity. Much larger strains were developed perpendicular to the major axis of an elliptical canal than in a circular canal. Average strain levels as high as 5% were obtained for an increase in IOP from 15to50mm Hg.
3D Mechanical Properties of the Layered Esophagus: Experiment and Constitutive Model
Authors: Yang W. , Fung T. C. , Chian K. S. , Chong C. K.
Published: December 2006

The identification of a three dimensional constitutive model is useful for describing the complex mechanical behavior of a nonlinear and anisotropic biological tissue such as the esophagus. The inflation tests at the fixed axial extension of 1, 1.125, and 1.25 were conducted on the muscle and mucosa layer of a porcine esophagus separately and the pressure-radius-axial force was recorded. The experimental data were fitted with the constitutive model to obtain the structure-related parameters, including the collagen amount and fiber orientation. Results showed that a bilinear strain energy function (SEF) with four parameters could fit the inflation data at an individual extension very well while a six-parameter model had to be used to capture the inflation behaviors at all three extensions simultaneously. It was found that the collagen distribution was axial preferred in both layers and the mucosa contained more collagen, which were in agreement with the findings through a pair of uniaxial tensile test in our previous study. The model was expected to be used for the prediction of stress distribution within the esophageal wall under the physiological state and provide some useful information in the clinical studies of the esophageal diseases.
Radio-Translucent 3-Axis Mechanical Testing Rig for the Spine in Micro-CT
Authors: Si-hoe K. M. , Teoh S. H. , Teo Jeremy
Published: December 2006

To date, no apparatus has yet been devised which would allow the study of bone microstructure of the whole vertebrae under mechanical loading. This paper outlines the design and development of a 3-axis radio-translucent mechanical testing rig for spinal research and testing. This rig is to be used in conjunction with a Shimadzu micro-CT scanner. Several tests were conducted to verify the feasibility of the rig design. First, the maximum range of deformation in compression, flexion\extension, and lateral bending that could be exerted on a goat lumbar functional spinal unit was evaluated using the noncontact digital markers method. Stepwise compression loading was also conducted on a single porcine vertebra and the loading data was compared to results obtained from an industrial grade compression testing machine. Finally, micro-CT scans of a porcine vertebra prior to and at a compression failure strain were obtained. The rig was confirmed to be able to exert pure moment loading in the above mentioned modes of deformation and the extent of deformation was comparable to previous documented results. The stepwise compression loading conducted in the rig was also found to effectively approximate a continuous loading of the same specimen in an industrial grade compression testing machine. Finally, resultant micro-CT images of isotropic resolution 32.80μm of a porcine vertebra loaded in the rig were obtained. For the first time, trabecular microarchitecture detail of a whole vertebra buckling under 12.1% failure compression strain loading was studied using voxel-data visualization software. These initial series of tests verify the feasibility of the rig as an apparatus incorporating spinal testing and imaging.
Randomized Controlled Comparison of Ofloxacin, Azithromycin, and an Ofloxacin-Azithromycin Combination for Treatment of Multidrug-Resistant and Nalidixic Acid-Resistant Typhoid Fever
Authors: Parry Christopher M. , Ho Vo Anh , Phuong Le Thi , Bay Phan Van Be , Lanh Mai Ngoc , Tung Le Thanh , Tham Nguyen Thi Hong , Wain John , Hien Tran Tinh , Farrar Jeremy J.
Published: December 2006

Isolates of
Salmonella enterica
serovar Typhi that are multidrug resistant (MDR, resistant to chloramphenicol, ampicillin, and trimethoprim-sulfamethoxazole) and have reduced susceptibility to fluoroquinolones (nalidixic acid resistant, Na
r
) are common in Asia. The optimum treatment for infections caused by such isolates is not established. This study compared different antimicrobial regimens for the treatment of MDR/Na
r
typhoid fever. Vietnamese children and adults with uncomplicated typhoid fever were entered into an open randomized controlled trial. Ofloxacin (20 mg/kg of body weight/day for 7 days), azithromycin (10 mg/kg/day for 7 days), and ofloxacin (15 mg/kg/day for 7 days) combined with azithromycin (10 mg/kg/day for the first 3 days) were compared. Of the 241 enrolled patients, 187 were eligible for analysis (186
S. enterica
serovar Typhi, 1
Salmonella enterica
serovar Paratyphi A). Eighty-seven percent (163/187) of the patients were children; of the
S. enterica
serovar Typhi isolates, 88% (165/187) were MDR and 93% (173/187) were Na
r
. The clinical cure rate was 64% (40/63) with ofloxacin, 76% (47/62) with ofloxacin-azithromycin, and 82% (51/62) with azithromycin (
P
= 0.053). The mean (95% confidence interval [CI]) fever clearance time for patients treated with azithromycin (5.8 days [5.1 to 6.5 days]) was shorter than that for patients treated with ofloxacin-azithromycin (7.1 days [6.2 to 8.1 days]) and ofloxacin (8.2 days [7.2 to 9.2 days]) (
P
< 0.001). Positive fecal carriage immediately posttreatment was detected in 19.4% (12/62) of patients treated with ofloxacin, 6.5% (4/62) of those treated with the combination, and 1.6% (1/62) of those treated with azithromycin (
P
= 0.006). Both antibiotics were well tolerated. Uncomplicated typhoid fever due to isolates of MDR
S. enterica
serovar Typhi with reduced susceptibility to fluoroquinolones (Na
r
) can be successfully treated with a 7-day course of azithromycin.
Involvement of Pyruvate Oxidase Activity and Acetate Production in the Survival of
Lactobacillus plantarum
during the Stationary Phase of Aerobic Growth
Authors: Goffin Philippe , Muscariello Lidia , Lorquet Frederique , Stukkens Aline , Prozzi Deborah , Sacco Margherita , Kleerebezem Michiel , Hols Pascal
Published: December 2006

In addition to the previously characterized pyruvate oxidase PoxB, the
Lactobacillus plantarum
genome encodes four predicted pyruvate oxidases (PoxC, PoxD, PoxE, and PoxF). Each pyruvate oxidase gene was individually inactivated, and only the knockout of
poxF
resulted in a decrease in pyruvate oxidase activity under the tested conditions. We show here that
L. plantarum
has two major pyruvate oxidases: PoxB and PoxF. Both are involved in lactate-to-acetate conversion in the early stationary phase of aerobic growth and are regulated by carbon catabolite repression. A strain devoid of pyruvate oxidase activity was constructed by knocking out the
poxB
and
poxF
genes. In this mutant, acetate production was strongly affected, with lactate remaining the major end product of either glucose or maltose fermentation. Notably, survival during the stationary phase appeared to be dramatically improved in the
poxB poxF
double mutant.
New Rapid and Simple Methods for Detection of Bacteria and Determination of Their Antibiotic Susceptibility by Using Phage Mutants
Authors: Ulitzur Nirit , Ulitzur Shimon
Published: December 2006

Three new methods applying a novel approach for rapid and simple detection of specific bacteria, based on plaque formation as the end point of the phage lytic cycle, are described. Different procedures were designed to ensure that the resulting plaques were derived only from infected target bacteria (“infectious centers”). (i) A pair of amber mutants that cannot form plaques at concentrations lower than their reversion rate underwent complementation in the tested bacteria; the number of plaques formed was proportional to the concentration of the bacteria that were coinfected by these phage mutants. (ii) UV-irradiated phages were recovered by photoreactivation and/or SOS repair mediated by target bacteria and plated on arecA uvrAbacterial lawn in the dark to avoid recovery of noninfecting phages. (iii) Pairs of temperature-sensitive mutants were allowed to coinfect their target bacteria at the permissive temperature, followed by incubation of the plates at the restrictive temperature to avoid phage infection of the host cells. This method allowed the omission of centrifuging and washing the infected cells. Only phages that recovered by recombination or complementation were able to form plaques. The detection limit was 1 to 10 livingSalmonellaorEscherichia coliO157 cells after 3 to 5 h. The antibiotic susceptibility of the target bacteria could also be determined in each of these procedures by preincubating the target bacteria with antibiotic prior to phage infection. Bacteria sensitive to the antibiotic lost the ability to form infectious centers.
Sequence Analysis of the
rfb
Loci, Encoding Proteins Involved in the Biosynthesis of the
Salmonella enterica
O17 and O18 Antigens: Serogroup-Specific Identification by PCR
Authors: Fitzgerald Collette , Gheesling Linda , Collins Marcus , Fields Patricia I.
Published: December 2006

We report sequencing of the O antigen encoded by the
rfb
gene cluster of
Salmonella enterica
serotype Jangwani (O17) and
Salmonella
serotype Cerro (O18). We developed serogroup O17- and O18-specific PCR assays based on
rfb
gene targets and found them to be sensitive and specific for rapid identification of
Salmonella
serogroups O17 and O18.
Antimicrobial Use and Resistance in Swine Waste Treatment Systems
Authors: Jindal Archana , Kocherginskaya Svetlana , Mehboob Asma , Robert Matthew , Mackie Roderick I. , Raskin Lutgarde , Zilles Julie L.
Published: December 2006

Chlortetracycline and the macrolide tylosin were identified as commonly used antimicrobials for growth promotion and prophylaxis in swine production. Resistance to these antimicrobials was measured throughout the waste treatment processes at five swine farms by culture-based and molecular methods. Conventional farm samples had the highest levels of resistance with both culture-based and molecular methods and had similar levels of resistance despite differences in antimicrobial usage. The levels of resistance in organic farm samples, where no antimicrobials were used, were very low by a culture-based method targeting fecal streptococci. However, when the same samples were analyzed with a molecular method detecting methylation of a specific nucleotide in the 23S rRNA that results in resistance to macrolides, lincosamides, and streptogramin B (MLS
B
), an unexpectedly high level of resistant rRNA (approximately 50%) was observed, suggesting that the fecal streptococci were not an appropriate target group to evaluate resistance in the overall microbial community and that background levels of MLS
B
resistance may be substantial. All of the feed samples tested, including those from the organic farm, contained tetracycline resistance genes. Generally, the same tetracycline resistance genes and frequency of detection were found in the manure and lagoon samples for each commercial farm. The levels of tetracycline and MLS
B
resistance remained high throughout the waste treatment systems, suggesting that the potential impact of land application of treated wastes and waste treatment by-products on environmental levels of resistance should be investigated further.
Isolation of Two Polyketide Synthase Gene Fragments from the Uncultured Microbial Symbiont of the Marine Bryozoan
Bugula neritina
Authors: Lopanik Nicole B. , Targett Nancy M. , Lindquist Niels
Published: December 2006

“
Candidatus
Endobugula sertula,” the uncultured microbial symbiont of the bryozoan
Bugula neritina
, produces ecologically and biomedically important polyketide metabolites called bryostatins. We isolated two gene fragments from
B. neritina
larvae that have high levels of similarity to polyketide synthase genes. These gene fragments are clearly associated with the symbiont and not with the host.
Diverse Responses to UV-B Radiation and Repair Mechanisms of Bacteria Isolated from High-Altitude Aquatic Environments
Authors: Fernández Zenoff V. , Siñeriz F. , Farías M. E.
Published: December 2006

Acinetobacter johnsonii
A2 isolated from the natural community of Laguna Azul (Andean Mountains at 4,560 m above sea level),
Serratia marcescens
MF42,
Pseudomonas
sp. strain MF8 isolated from the planktonic community, and
Cytophaga
sp. strain MF7 isolated from the benthic community from Laguna Pozuelos (Andean Puna at 3,600 m above sea level) were subjected to UV-B (3,931 J m
−2
) irradiation. In addition, a marine
Pseudomonas putida
strain, 2IDINH, and a second
Acinetobacter johnsonii
strain, ATCC 17909, were used as external controls. Resistance to UV-B and kinetic rates of light-dependent (UV-A [315 to 400 nm] and cool white light [400 to 700 nm]) and -independent reactivation following exposure were determined by measuring the survival (expressed as CFU) and accumulation of cyclobutane pyrimidine dimers (CPD). Significant differences in survival after UV-B irradiation were observed:
Acinetobacter johnsonii
A2, 48%;
Acinetobacter johnsonii
ATCC 17909, 20%;
Pseudomonas
sp. strain MF8, 40%; marine
Pseudomonas putida
strain 2IDINH, 12%;
Cytophaga
sp. strain MF7, 20%; and
Serratia marcescens
, 21%. Most bacteria exhibited little DNA damage (between 40 and 80 CPD/Mb), except for the benthic isolate
Cytophaga
sp. strain MF7 (400 CPD/Mb) and
Acinetobacter johnsonii
ATCC 17909 (160 CPD/Mb). The recovery strategies through dark and light repair were different in all strains. The most efficient in recovering were both
Acinetobacter johnsonii
A2 and
Cytophaga
sp. strain MF7;
Serratia marcescens
MF42 showed intermediate recovery, and in both
Pseudomonas
strains, recovery was essentially zero. The UV-B responses and recovery abilities of the different bacteria were consistent with the irradiation levels in their native environment.
Change in Substrate Preference ofStreptomycesAminopeptidase through Modification of the Environment around the Substrate Binding Site
Authors: Arima Jiro , Uesugi Yoshiko , Iwabuchi Masaki , Hatanaka Tadashi
Published: December 2006

We attempted to alter the substrate preference of aminopeptidase fromStreptomyces septatusTH-2 (SSAP). Because Asp198 and Phe221 of SSAP are located in the substrate binding site, we screened 2,000 mutant enzymes with D198X/F221X mutations. By carrying out this examination, we obtained two enzymes; one specifically hydrolyzed an arginyl derivative, and the other specifically hydrolyzed a cystinyl derivative (65- and 12.5-fold higherkcatvalues for hydrolysis ofp-nitroanilide derivatives than those of the wild type, respectively).