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Pale green lethal (PGL) is a recessive genetic disorder of apple (Malus) characterized by severe chlorophyll deficiency and seedling lethality. Following germination, seedlings cannot photosynthesize and do not survive beyond the cotyledon stage. PGL carriers are prevalent in cultivated apple (Malus × domestica Borkh.) germplasm, and a cross between two heterozygotes results in 25 % lethality. This high mortality rate represents a significant loss of time, resources, and effort. It also causes segregation distortion which complicates genetic analysis of linked traits. We mapped PGL to the top of Linkage Group 16. Using a combination of genetic and biochemical methods, we identified the apple ortholog of PHYLLO (MdPHYLLO) as the gene responsible for PGL disorder. PHYLLO encodes a multifunctional enzyme that catalyzes key steps in the biosynthesis of phylloquinone (vitamin K1). PGL seedlings do not produce phylloquinone yet can be kept alive and healthy through exogenous application of phylloquinone. The PGL allele of MdPHYLLO contains a mutation that alters a highly conserved amino acid in one of the protein’s enzymatic modules. This mutation is present in all PGL carriers tested and absent from all non-carriers. Reasons why the PGL allele of MdPHYLLO is so widespread in cultivated apple are discussed.

Columnar apples trees, originated from a bud mutation ‘Wijcik McIntosh,’ develop a simple canopy and set fruit on spurs. These characteristics make them an important genetic resource for improvement of tree architecture. Genetic studies have uncovered that columnar growth habit is a dominant trait and is caused by a retroposon insertion that induces the expression of the neighboring gene Co encoding a 2OG-Fe(II) oxygenase. Here we report the genetic mapping of two loci of recessive suppressors (genes) c2 (on Chr10) and c3 (on Chr9) that are linked to repression of the retroposon-induced Co gene expression and associated columnar phenotype in 275 F1 seedlings, which were developed from a reciprocal cross between two columnar selections heterozygous at the Co locus. The mapping was accomplished by sequencing a genomic pool comprising 18 columnar seedlings and another pool of 16 standard seedlings that also carry the retroposon insertion, and by exploring DNA variants of segregation types that are informative for mapping recessive traits in apple. The informative segregation types include , , , , and , where each letter denotes one of the four DNA bases and the letters in bold represent variants in relation to the reference genome. The alleles in each first and third positions are assumed in linkage with the recessive suppressors’ allele in the two parents, respectively. Using RNA-seq analysis, we further revealed that the Co gene together with the differentially expressed genes under loci c2 and c3 formed a co-expression gene-network module associated with growth habit, in which 12 MapMan Bins were enriched.

Phloridzin is a phenolic compound unique to apple (Malus domestica (Suckow) Borkh.) and its wild relatives. Since its discovery, phloridzin has been researched for its nutraceutical properties, including anti-diabetic, anti-cancer, and antioxidant activities, making phloridzin a potential target for nutritional improvement in new apple cultivars. However, phloridzin accumulates at significantly lower concentrations in fruit than in vegetative tissues and seeds. In ‘Golden Delicious’ and its sports, we observed higher phloridzin content in peels of sports with a cuticle disorder termed russet. In russeted apples, the smooth, waxy fruit cuticle is partially or entirely replaced by a corky layer, induced through environmental and genetic effects. To understand the variation of phloridzin content and fruit russet in apple fruit, we surveyed 108 accessions with variation in russeting from the USDA-ARS Malus germplasm collection in Geneva, NY. Russeting in apple fruit ranged from 0 to 100%, and phloridzin content ranged from 24.3 to 825.0 μg/g in peels. Mean phloridzin content varied significantly between russeting groups; in groups with light (0–5%), medium–high (70–80%), and high (90–100%) russeting mean phloridzin content was 115.2, 591.2, and 378.8 μg/g, respectively. We observed that genetic factors and russeting are strong predictors of phloridzin content in peels, but not fruit flesh or leaves. Conversely, other peel phenolics are negatively associated with russeting. We observed variable phloridzin content related to russet incidence during fruit development in ‘Golden Delicious’ (low to medium russet) and its sports, ‘Empress Spur’ (low russet), ‘Razor’ (complete russet), and ‘Sergeant Russet’ (medium to high russet).

Staff on a mother–baby unit of a large suburban Level II facility identified the need to provide specialized nursing care to women affected by opioids. The manager of the unit recognized inconsistencies in care and frustration expressed by women and staff. She recruited a CORE (Champion for our Opiate patients using Respectful and Relevant Engagement and Education) group of staff nurses to care for these women. CORE nurses received specialized education and resources and served as the primary nurses for women admitted to the unit with a positive urine drug screening result or a history of drug use during pregnancy. Having a CORE team has brought a consistent approach when providing care to families affected by opioids.

Dihydrochalcones, beneficial phenolic compounds, are abundant in Malus Mill. species, particularly in vegetative tissues and seeds. Phloridzin (phloretin 2′-O-glucoside) is the primary dihydrochalcone in most Malus species including cultivated apple, Malus × domestica Borkh. A few species contain sieboldin (3-hydroxyphloretin 4′-O-glucoside) or trilobatin (phloretin 4′-O-glucoside) in place of phloridzin, and interspecific hybrids may contain combinations of phloridzin, sieboldin, and trilobatin. Proposed health benefits of phloridzin include anti-cancer, antioxidant, and anti-diabetic properties, suggesting the potential to breed apples for nutritional improvement. Sieboldin and trilobatin are being investigated for nutritional value and unique chemical properties. Although some of the biosynthetic steps of dihydrochalcones are known, little is known about the extent of variation within Malus germplasm. This research explores the genetic diversity of leaf dihydrochalcone content and composition in Malus germplasm. Dihydrochalcone content was measured using high performance liquid chromatography (HPLC) from leaf samples of 377 accessions, representing 50 species and interspecific hybrids from the USDA-Agricultural Research Service (ARS) National Plant Germplasm System Malus collection. Within the accessions sampled, 284 accessions contained phloridzin as the primary dihydrochalcone, one had only trilobatin, two had phloridzin and trilobatin, 36 had sieboldin and trilobatin, and 54 had all three. Leaf phloridzin content ranged from 17.3 to 113.7 mg/g with a heritability of 0.76 across all accessions. Beyond the potential of dihydrochalcones for breeding purposes, dihydrochalcone composition may be indicative of hybridization or species misclassification.

The manner in which ‘third generation’ Mexican-Americans are identified, predicated on self-reported ethnic identity rather than grandparental nativity, is imprecise and potentially confounded with...

Identifying and exploiting three informative DNA variant segregation types in pooled genome sequencing analysis of the weeping phenotype in Malus empowers an effective genetic mapping strategy in out-crossing woody species., To unlock the power of next generation sequencing-based bulked segregant analysis in allele discovery in out-crossing woody species, and to understand the genetic control of the weeping trait, an F1 population from the cross ‘Cheal’s Weeping’ × ‘Evereste’ was used to create two genomic DNA pools ‘weeping’ (17 progeny) and ‘standard’ (16 progeny). Illumina pair-end (2 × 151 bp) sequencing of the pools to a 27.1× (weeping) and a 30.4× (standard) genome (742.3 Mb) coverage allowed detection of 84562 DNA variants specific to ‘weeping’, 92148 specific to ‘standard’, and 173169 common to both pools. A detailed analysis of the DNA variant genotypes in the pools predicted three informative segregation types of variants: (type I) in weeping pool-specific variants, and (type II) and (type III) in variants common to both pools, where the first allele is assumed to be weeping linked and the allele shown in bold is a variant in relation to the reference genome. Conducting variant allele frequency and density-based mappings revealed four genomic regions with a significant association with weeping: a major locus, Weeping (W), on chromosome 13 and others on chromosomes 10 (W2), 16 (W3), and 5 (W4). The results from type I variants were noisier and less certain than those from type II and type III variants, demonstrating that although type I variants are often the first choice, type II and type III variants represent an important source of DNA variants that can be exploited for genetic mapping in out-crossing woody species. Confirmation of the mapping of W and W2, investigation into their genetic interactions, and identification of expressed genes in the W and W2 regions provided insight into the genetic control of weeping and its expressivity in Malus.

Prior research has examined the incorporation outcomes among unauthorized migrants after implementation of the 1986 Immigration Reform and Control Act (IRCA). However, few studies have evaluated how legalization opportunities produce gendered outcomes among the second-generation children of unauthorized immigrants. We examine the association of legalization opportunities provided through IRCA with the years of schooling attained by the sons and daughters of Mexican American immigrants. By distinguishing likely eligibility for one of two programs implemented under IRCA—the Legally Authorized Workers and Special Agricultural Workers programs—we consider whether type of legalization program matters by assessing gender differences in schooling among children of Mexican immigrants. Although legalization provides a substantial educational premium for the children of Mexican immigrants regardless of gender, the size of the legalization premium is smaller, on average, for sons than daughters. The advantage to daughters is especially notable among those with parents eligible for the Special Agricultural Workers program. We consider these findings in the context of theories of immigrant incorporation and intergenerational mobility.

This chapter examines the size and scope of international migration, its theoretical underpinnings, and measures of migration. More than 3% of the world’s population consists of international migrants, who are not evenly distributed but concentrated in high-income destination countries. The countries of origin are becoming more diverse, with India now providing more migrants than any other. Immigration policies in destination countries increasingly favor highly educated immigrants. The chapter focuses also on the United States, the largest receiving country for immigrants. There, the ongoing retirement of the Baby Boom, decades of below-replacement fertility among the native-born population, and growth in college attendance have given rise to a need for more less-skilled workers, many of whom are immigrants.

This paper invokes a membership-exclusion theoretical model of immigrant integration to investigate political incorporation. Specifically, we examine the extent to which unauthorized migration status is associated with general and particular political knowledge and with other kinds of structural incorporation. In the analyses, we use data from the initial wave of the 2012 Latino Immigrant National Election Study (LINES) targeting adult immigrants from Spanish-speaking countries in Latin America. Consistent with theoretical expectations, we find that unauthorized Latino immigrants have significantly lower levels of general political knowledge than green card holders, those with other government IDs, or naturalized citizens, and that the difference between the unauthorized and the legal groups holds up when controls are introduced for exposure (quantity and quality of time in the country) and various kinds of structural incorporation, although differences among the legal groups do not. Thus, forms of structural integration mediate the effects of exposure on acquisition of general political knowledge by legal immigrants, but they do not for unauthorized immigrants, providing evidence that membership exclusion severely restricts political incorporation. At the same time, unauthorized immigrants show more awareness about changes in the unemployment rate than legal immigrants do, a result consistent both with their main reason for migration (to work) and with their having recourse only to collective action as a form of political expression.

Dihydrochalcones (DHCs) are a distinctive characteristic of Malus species, with phloridzin as the major DHC in most Malus species, including cultivated apple. DHCs in apple have unique chemical properties with commercial and nutritional value and may yield important insights into the evolution and physiology of apple. A few species produce sieboldin and trilobatin instead of phloridzin, and interspecific hybridization produce offspring with combinations of phloridzin, sieboldin, and trilobatin. Using Malus prunifolia PI 89816 as a common male parent, five F1 populations were developed to understand the genetic basis of these DHCs in Malus. We measured DHC content in each population and observed segregation into five distinct DHC profiles, which fit a model for three independently segregating loci. QTL associated with DHC content were identified on linkage groups 7 and 8 of the Malus genome using linkage analysis with a cross of NY-152 by M. prunifolia PI 589816 and association mapping with a Malus germplasm collection. In addition to DHC segregation, we observed variation in the relative proportions of phloridzin, sieboldin, and trilobatin. The QTL identified represent a critical step in understanding the genetic controllers of DHC content in Malus.

Objective To use high-fidelity human patient simulation to enhance teamwork and communication during maternity care emergencies. Design Quality improvement initiative. Setting/Local Problem The labor and delivery team at a large suburban Level 2 facility in the Midwestern United States sought to apply evidence and use simulation to improve communication and teamwork. Participants Approximately 170 maternity care staff members, including nurses, anesthesia providers, and pediatric and obstetric physicians. Intervention/Measurements During each simulation, there were two scenarios with a debriefing session at the end of each. Teamwork and communication were evaluated using participant surveys. Results Participants reported improved communication (p = .031) and teamwork (p = .041) after simulation. Additionally, 81% of respondents believed that their ability to perform clinical skills improved. Conclusion Use of high-fidelity human patient simulation was associated with improved teamwork and communication for a maternity care team. Simulation has been incorporated into standard education. We hope to sustain successful outcomes by providing ongoing simulation experiences for labor and delivery staff annually.

This paper examines the degree to which fertility and socio-demographic changes are reducing the size of the U.S.-born less-skilled working-age population in the United States. By less-skilled, we mean persons with a high school diploma or less. By consequences of fertility change, we mean the repercussions of both high fertility in past decades (the Baby Boom) and below replacement native-born fertility in more recent decades. By consequences of socio-demographic change, we refer to the rise in the proportion of the population starting and finishing college. In the context of evidence indicating that the relative size of economic sectors hiring less-skilled workers has not diminished in recent decades (with the exception of manufacturing employment), we suggest these demographic and social changes imply that the country will continue to rely on less-skilled immigrant workers. We assess this idea based on analyses of U.S. Census and American Community Survey data for decennial census years starting in 1970 and running through 2010. The results show a net decline of more than 7 million persons in the U.S.-born less-skilled working-age population since 1990, and a looming decline of more than 12 million between now and 2030. Educational upgrading, especially among women, contributes a notable share to these shifts, but so does earlier high fertility (the aging of the Baby Boomers) and more recent low native fertility. Interestingly, the number of less-skilled unauthorized immigrants living in the United States in 2010 is smaller than the decline in the size of the less-skilled U.S.-born working-age population over the same period.

Apple (Malus × domestica Borkh.) is one of the top three US fruit crops in production and value. Apple production has high costs for land, labor and inputs, and orchards are a long-term commitment. Production is dominated by only a few apple scion and rootstock cultivars, which increases its susceptibility to dynamic external threats. Apple crop wild relatives, including progenitor species Malus sieversii (Ledeb.) M. Roem., Malus orientalis Uglitzk., Malus sylvestris (L.) Mill., and Malus prunifolia (Willd.) Borkh., as well as many other readily hybridized species, have a wide range of biotic and abiotic stress resistances as well as desirable productivity and fruit quality attributes. However, access to wild materials is limited and wild Malus throughout the world is at risk of loss due to human encroachment and changing climatic patterns. The USDA-ARS National Plant Germplasm System (NPGS) Malus collection, maintained by the Plant Genetic Resources Unit in Geneva, NY, US is among the largest collections of cultivated apple and Malus species in the world. The collection currently has 5004 unique accessions in the field and 1603 seed accessions representing M. × domestica, 33 Malus species, and 15 hybrid species. Of the trees in the field, 3,070 are grafted and are represented by a core collection of 258 individuals. Many wild species accessions are represented as single seedlings (non-grafted). The crop vulnerability status of apple in the US is moderate because although there are a few breeders developing new commercial cultivars who also access Malus species, threats and challenges include new diseases, pests, and changing climate combined with industry needs and consumer demands, with a limited number of cultivars in production.

Despite the demonstrated importance of gibberellins (GAs) as regulators of fruit tree stature, information on their in vivo metabolism in apple vegetative tissues is still lacking. To determine whether the GA content and metabolism differs between dwarf and standard phenotypes and the influence of rootstocks, [14C]GA12, a common precursor of all GAs in higher plants, was applied to vigorously growing apple (Malus ×domestica) shoots collected from the scion cultivar Redcort on MM.106, a growth-promoting rootstock, and dwarf and standard seedlings on their own roots from progeny 806 (a cross between a breeding selection with reduced stature and an advanced breeding selection with a standard tree form). Twenty-one metabolites were identified by high-performance liquid chromatography (HPLC) and used as tracers for the purification of endogenous GAs. The existence of endogenous and [2H]-labeled GA12, GA15, GA53, GA44, GA19, GA20, and GA3 was demonstrated by gas chromatography–mass spectrometry (GC-MS); GA20 was the major GA present, with slightly less GA19 and GA44, and with GA3 present at approximately one-third the level of GA20. Despite specific searching, neither GA4, GA7, GA1, nor GA29 was found, showing that [14C]GA12 is metabolized mainly through the 13-hydroxylation pathway and that GA3 is a bioactive GA in apple vegetative tissues. The invigorating rootstock led to a slow GA metabolic rate in ‘Redcort’. For self-rooted plants, the same GAs were identified in dwarf and standard seedlings from progeny 806, although standard plants metabolized at twice the speed of dwarf plants. Young branches of dwarf 806 plants treated with GA3 were one-third longer with more nodes but similar in internode length. We conclude that the dwarf phenotype in progeny 806 is not caused by a lack of certain GAs in the GA biosynthesis pathway downstream of GA12.

Establishing marker-locus-trait associations to enable marker-assisted breeding depends on having an extensive, reliable database for phenotypic traits of interest in relevant germplasm. A reference germplasm set of 467 apple (Malus 3domestica Borkh.) cultivars, selections, and seedlings (referred to as individuals) was identified as part of the USDA-Specialty Crop Research Initiative (SCRI) project, RosBREED. The germplasm set provides efficient allelic representation of current parents in RosBREED demonstration apple breeding programs at Cornell University, Washington State University, and the University of Minnesota. Phenotyping at the three locations was conducted according to standardized protocols, focusing on fruit traits evaluated at harvest and after 10 and 20 weeks of refrigerated storage. Phenotypic data were collected for the sensory texture traits of firmness, crispness, and juiciness as well as for instrumental texture measures. In 2010 and 2011, fruit from 216 and 330 individuals, respectively, were harvested and a total of 369 individuals were evaluated over the two years. Correlations between sensory and instrumental texture measures were high in some instances. Moderate year-to-year repeatability of trait values was observed. Because each location had a largely unique set of individuals, as well as differing environmental conditions, means, ranges, and phenotypic variances differed greatly among locations for some traits. Loss of firmness and crispness during storage was more readily detected instrumentally than by the sensory evaluation. Fruit texture traits, significant to apple breeder decision-making yet unobservable until tree maturity, are ideal candidates for marker-assisted breeding (MAB) and markerassisted selection (MAS). Marker-locus-trait associations, validated in germplasm relevant to a particular breeding program, facilitate MAB (Bliss, 2010). MAB is used to select parents with favorable alleles and MAS is imposed on seedling populations to eliminate those with unfavorable allele combinations. Both MAB and MAS can reduce time and expense for new cultivar development in a tree fruit breeding program. Fruit texture is a focus of breeders because of its role in shaping consumer acceptance of new apple cultivars. Harker et al. (2003) reviewed studies that investigated consumer preferences for apple and factors influencing willingness to buy. They reported that although subsets of consumers vary in fruit quality expectations, most adults respond to texture and acidity as determinants of fruit quality. In a study of New Zealand consumers, adults preferred harder and crisper apples. Although the authors reported that consumers remember differences in apple texture for days, Harker et al. (2003) predicted that fruit quality standards will evolve as consumers’ expectations change. Speeding the breeding process through the use of molecular markers will aid apple breeders in developing higher quality fruit. A study using ‘Red Delicious’, ‘Gala’, and ‘Braeburn’ showed that in certain cultivars, firmness is of high importance to consumers, especially in combination with other fruit quality factors: firm apples, above a 53Newton threshold, can be improved on by changes in titratable acidity (TA) and soluble solids content (SSC), but soft apple acceptance cannot be improved on with changes in TA or SSC (Harker et al., 2008). These findings highlighted the use of genetic markers to select for fruit texture traits. Studies of apple texture have used both sensory panels and instrumental measures (e.g., Evans et al., 2010; Ioannides et al., 2007; McKay et al., 2011; Zdunek et al., 2011). Differences in terms used to describe texture as well as their definitions make comparing sensory panel results difficult. For instance, the meaning of the term ‘‘crispness’’ differs across studies. Fillion and Kilcast (2002), using a trained sensory panel and a consumer panel, defined the term ‘‘crunchy’’ as describing lower-pitched sounds that continue throughout chewing, whereas ‘‘crisp’’ described a higher-pitched sound resulting from the clean split of the first bite. Both crisp and crunchy designations, when applied to food, express that the material breaks in the mouth rather than buckling or deforming. By studying sounds during biting dry and wet crisp foods, Vickers and Bourne (1976) defined the crispness sensation as a characteristic sound of a range of frequencies emitted during biting. For a thorough discussion of the crispness sensation, refer to Roudaut et al. (2002). In our study, described by Evans et al. (2012), ‘‘crispness’’ refers to the intensity of the cracking noise of the first bite. ‘‘Firmness’’ is equivalent to ‘‘hardness’’ and determined while chewing. ‘‘Juiciness’’ is expressed juice on chewing. A trained sensory panel, as small as three experienced individuals, has been shown to be reliable in a postharvest study of fruit texture (Brookfield et al., 2011). That panel was able to discern greater separation among cultivars than was achieved with instrumental measures. Although sensory panels more closely mimic consumer perception of fruit texture, they can be time-consuming and difficult to standardize. Puncture tests, performed with various mechanized penetrometers, are typically used to determine firmness and juiciness (e.g., Harker et al., 2006). Harker et al. (2002) found puncture tests superior to chewing sounds and tensile measurements in forecasting sensory panelists’ perception of texture traits. The Mohr Digi-Test (Mohr and Associates, Richland, WA) computerized penetrometer captures data that correlate well with sensory firmness and sensory crispness by collecting constant velocity measurements (Evans et al., 2010). This is especially useful, because crispness has proven difficult to measure instrumentally with other devices. Received for publication 19 Dec. 2012. Accepted for publication 22 Jan. 2013. Funded by the Specialty Crop Research Initiative Competitive Grant 2009-51181-05808 of the USDA’s National Institute of Food and Agriculture. To whom reprint requests should be addressed; e-mail lubyx001@umn.edu. 296 HORTSCIENCE VOL. 48(3) MARCH 2013 Establishing marker-locus-trait associations for texture traits depends on having an extensive, reliable phenotype database for traits of interest in breeding germplasm. Without high-quality phenotypic data, association statistics that link genomic sequences to traits cannot realize full potential (Bassil and Volk, 2010). Moreover, when standardized phenotyping protocols are used across several breeding programs, the resulting large data sets give more power to studies that detect and characterize quantitative trait loci (QTL) than would be had if each program conducted a smaller, isolated study. A reference germplasm set of 467 individual genotypes including cultivars, selections, and seedlings was identified as part of the USDA-SCRI RosBREED project. The germplasm set provides efficient allelic representation of current parents in the large, publicly funded U.S. apple breeding programs of Cornell University (CU), Washington State University (WSU), and the University of Minnesota (UMN). Extensive phenotypic data, including instrumental and sensory measures of fruit texture, were collected on these individuals at each location in the years 2010 and 2011 under three regimes: at harvest, after 10 weeks of cold storage and 1 week at room temperature, and after 20 weeks of cold storage and 1 week at room temperature. Phenotypic data were collected adhering to a standardized protocol (Evans et al., 2012). The objective in this article is to elaborate on methods used to obtain data on sensory and instrumental measures of fruit texture traits in the RosBREED apple Crop Reference Set (CRS) and describe variation and repeatability observed for these traits. We also report correlations between sensory and instrumental measures used in this study. Materials and Methods Plant material. The RosBREED apple CRS and supplementing individuals included 154 cultivars and parental selections as well as 313 seedlings of families chosen to provide efficient allelic representation of important breeding parents for a total of 467 related individuals. Subsets of the RosBREED CRS were grown at the UMN Horticultural Research Center near Chaska, MN, at the WSU Tree Fruit Research & Extension Center in Wenatchee, WA, and at the CU New York State Agricultural Experiment Station in Geneva, NY. Evaluation of a reference Fig. 1. Apple equatorial slice demonstrating MDT-1 fruit texture measures described by Evans et al. (2010) and Mohr and Mohr (2000). R1 is the outer area of the apple directly below the skin, R2 is the main edible portion of the fruit, and R3 contains the core. Red lines indicate regions in which traits are determined. Fig. 2. Proportions of variance attributable to year, individual, sampling and year 3 individual for fruit texture measures at three locations at harvest. Analysis of variance was used. Data from University of Minnesota (UMN), Washington State University (WSU), and Cornell University (CU) are shown in shades of blue, purple, and green, respectively. Abbreviations are as follows: A1, A2 = average pressure regions 1 and 2, respectively (N); C0 = creep at boundary between regions 1 and 2 (cm); Cn = crispness measurement (derived value); E2 = pressure at core boundary (N); M1, M2 = maximum pressure regions 1 and 2, respectively (N); OAH = overall average hardness (N); OMH = overall maximum hardness (N); QF = quality factor (derived value). The sensory measures of crispness, firmness, and juiciness were assessed on a 5-point scale. HORTSCIENCE VOL. 48(3) MARCH 2013 297 | BREEDING, CULTIVARS, ROOTSTOCKS, AND GERMPLASM RESOURCES

Current typologies of migration tend to distinguish sharply between international and internal migration. While some defend this cleavage as vital for emphasizing the politics of international migration, others view it as inhibiting the development of theory by unnecessarily privileging the nation-state as a unit of analysis. The conceptual gap between internal and international migration appears to depend on the level of analysis and context. Where migration behavior involves decisions made by individuals or households, international migration generally is explained as another form of long-distance migration. At the macro-analytic level, however, the context of migration matters. If analysts still view migration in behavioral terms or as a response to population growth or development, international migration remains an extension of long-distance migration. But when analysts emphasize migration in legal or political terms, as an outgrowth of the competition of political economies or as a function of the state’s ability to determine who qualifies for membership, international migration is viewed as differing fundamentally from internal migration. One way to clarify the argument would be to shift to a different cleavage, the distinction between authorized and unauthorized migration, as perhaps more salient to migrants now than the difference between internal and international migration. Unauthorized migration can have enormous consequences for migrants, and as the Chinese hukou system of household registration has shown, it is not confined to international movement.

This research compares cities between and within the United States and Europe with respect to their dimensionality and degree of immigrant incorporation. Based on theoretical perspectives about immigrant incorporation, structural differentiation and national incorporation regimes, we hypothesize that more inclusionary (MI) cities will show more dimensions of incorporation and more favorable incorporation outcomes than less inclusionary (LI) places, especially in regard to labor market and spatial variables. We use data from recent major surveys of young adult second-generation groups carried out in Los Angeles, New York, and 11 European cities to assess these ideas. The findings indicate that second-generation immigrants in New York (MI) and in European MI places (i.e. cities in the Netherlands, Sweden and France) show greater dimensionality of incorporation (and thus by implication more pathways of advancement) respectively than is the case in Los Angeles (LI) or in European LI places (i.e. cities in Austria, Germany, and Switzerland). We discuss the significance of these results for understanding how the structures of opportunity confronting immigrants and their children in various places make a difference for the nature and extent of their integration.

This article assesses the labor market implications of less-skilled migration to the United States. It emphasizes how recent social, demographic, and economic trends have reduced the availability of less-skilled native workers, while new low-education immigrant workers compete with other less-skilled immigrants for available low-skilled jobs. Declines in native fertility to substantially below replacement levels, together with native educational upgrading, have substantially reduced the size of the less-skilled native-born labor pool in the past 30 years, even below the level of need. This trend cannot be explained by declines in low-skilled manufacturing employment. Other factors also serve to exacerbate the size of the shortfall in the availability of less-skilled natives, including mismatches in the locations of low-education natives and less-skilled jobs. Nativity differences in health, physical disability, and substance abuse also operate to widen the gap. The resulting void has largely been filled by increasing numbers of less-skilled immigrant workers. These patterns underscore the need for public policies that provide both less-skilled labor and reductions in social and economic inequalities in the United States.

The USDA - Specialty Crop Research Initiative-funded RosBREED project is focused on enabling marker-assisted breeding in the Rosaceae. New molecular tools for selection need to be developed before this technology will be widely accepted and applied to apple breeding programs. As well as detailed genotypic data of inter-related progenies, parents and ancestor cultivars, fully descriptive phenotypic data also need to be collected. For apple, fruit phenotyping begins at harvest, followed by 10 and 20 weeks regular storage, each followed by 7 days shelf life at room temperature. The standardized phenotyping protocols agreed by breeding teams in Washington, Minnesota and New York states will be presented in this paper.

This article investigates the transnational behaviour of the children of immigrants – the second generation – in 11 European and two U.S. cities. We find evidence that transnational practices such as visits to the home country, remittances and use of ethnic media persist only among a minority of the second generation. At a personal level, these second-generation transmigrants are less socio-culturally integrated but more economically integrated in the host country. They also tend to live in those cities and countries with policies that are more assimilationist or exclusionary than multicultural. keywords: Immigrant integration; second generation; transnationalism; comparative immigration contexts; multiculturalism

Apple fruit flavor is greatly affected by the level of malic acid, which is the major organic acid in mature apple fruit. To understand the genetic and molecular basis of apple fruit acidity, fruit juice pH and/or titratable acidity (TA) were measured in two half-sib populations GMAL 4595 [Royal Gala × PI (Plant Introduction) 613988] and GMAL 4590 (Royal Gala × PI 613971) of 438 trees in total. The maternal parent Royal Gala is a commercial variety and the paternal parents are two M. sieversii (the progenitor species of domestic apple) elite accessions. The low-acid trait segregates recessively and the overall acidity variations in the two populations were primarily controlled by the Ma (malic acid) locus, a major gene discovered in the 1950s (Nybom in Hereditas 45:332–350, 1959) and later mapped to linkage group 16 (Maliepaard et al. in Theor Appl Genet 97:60–73, 1998). The allele Ma has a strong additive effect in increasing fruit acidity and is incompletely dominant over ma. QTL (quantitative trait locus) analyses in GMAL 4595 mapped the major QTL Ma in both Royal Gala and PI 613988, the effects of which explained 17.0–42.3% of the variation in fruit pH and TA. In addition, two minor QTL, tentatively designated M2 and M3, were also detected for fruit acidity, with M2 on linkage group 6 of Royal Gala and M3 on linkage group 1 of PI 613988. By exploring the genome sequences of apple, eight new simple sequence repeat markers tightly linked to Ma were developed, leading to construction of a fine genetic map of the Ma locus that defines it to a physical region no larger than 150 kb in the Golden Delicious genome.

The modulus and breaking strength of the skins of different apples were measured: McIntosh, Red Delicious, and Empire stored under controlled atmosphere; McIntosh stored at 1.7°C without atmospheric control, and Honey Crisp and Crimson Gala grown under light and heavy crop conditions. The moduli of the skins of Honey Crisp and Crimson Gala were lower (P < 0.05), than those of Empire, McIntosh, and Red Delicious. Peak puncture force values of McIntosh, Red Delicious, and Empire were lower (P < 0.05) than those of Crimson Gala and Honey Crisp; the contribution of the skin of the Honey Crisp apples to the peak force was least among all the studied apples.

Malus sieversii is a progenitor species of domestic apple M. × domestica. Using population “GMAL 4595” of 188 individuals derived from a cross of Royal Gala × PI 613988 (apple scab resistant, M. sieversii), 287 SSR (simple sequence repeats) loci were mapped. Of these SSRs, 80 are published anchors and 207 are newly developed EST (expressed sequence tag) contig-based SSRs, representing 1,630 Malus EST accessions in GenBank. Putative gene functions of these EST contigs are diverse, including regulating plant growth, development and response to environmental stresses. Among the 80 published SSRs, 18 are PI 613988 specific, 38 are common and 24 are Royal Gala specific. Out of the 207 newly developed EST contig-based SSRs, 79 are PI 613988 specific, 45 are common and 83 are Royal Gala specific. These results led to the construction of a M. sieversii map (1,387.0 cM) of 180 SSR markers and a Royal Gala map (1,283.4 cM) of 190 SSR markers. Mapping of scab resistance was independently conducted in two subsets of population “GMAL 4595” that were inoculated with Ventura inaequalis races (1) and (2), respectively. In combination with the two major resistance reactions Chl (chlorotic lesions) and SN (stellate necrosis) to each race, four subsets of resistance data, i.e., Chl/race (1), SN/race (1), Chl/race (2) and SN/race (2), were constituted and analyzed, leading to four resistance loci mapped to the linkage group 2 of PI 613988; SNR1 (stellate necrosis resistance to race (1)) and SNR2 are tightly linked in a region of known scab resistance genes, and ChlR1 (Chlorotic lesion resistance to race (1)) and ChlR2 are also linked tightly but in a region without known scab resistance genes. The utility of the two linkage maps, the new EST contig-based markers and M. sieversii as sources of apple scab resistance are discussed.

To assess pollen functionality of transgenic apple trees, in vitro pollen germination and tube growth were evaluated. Flowers of transgenic “Royal Gala” apple lines containing attacin E gene to confer resistance to fire blight (Erwinia amylovora), or antisense 1-aminocyclopropane-1-carboxylic acid synthase (ACS) construct to improve fruit storage life, were collected, and pollen was harvested. Amongst the 19 transgenic lines, pollen from three lines transformed with an ACS-antisense vector consistently had significantly lower germination rate compared to “Royal Gala”; however, no correlation between ACS level in fruit and pollen germination rate was observed. Western blots showed that the amounts of the lytic protein, attacin, varied in pollen of the four attacin-transgenic lines sampled. There was no significant correlation between attacin level in the pollen and pollen germination rate or pollen tube growth. The addition of boric acid to the germination buffer enhanced germination in attacin-tr...

This article examines the nature and degree of spatial integration across generations among young adults of Mexican origin in metropolitan Los Angeles. Drawing on a new, unique data set that covers more than four generations of persons of Mexican origin, the research tests the extent to which residential settlement patterns follow two potential trajectories: one specified by a model of traditional spatial assimilation, which views economic and ethnic integration as increasing steadily across generations, or a new model of delayed spatial assimilation, which depicts residential mobility as stalling for a generation or more, in part because of intergenerational family obligations up through the second generation. While individual–level socioeconomic characteristics tend to rise uniformly in support of the classic assimilation model, neighborhood–level evidence shows that substantial spatial integration does not emerge until the third generation—a finding supporting the delayed assimilation model. Also, generational differences in the proportion Anglo of respondents’ neighborhoods outpace differences in median income. These results are consistent with the idea that delayed spatial assimilation involves an additional early phase of incorporation for those of Mexican origin.

The Welfare Reform Act of 1996 generally restricted immigrants' eligibility for welfare to those who had naturalized. By increasing the salience of naturalization, the law provides a unique opportunity to examine how social and economic contexts of reception influence immigrants' pursuit of citizenship. This paper summarizes instrumental-legal (IL) and social-contextual (SC) theoretical perspectives on the foundations of citizenship and develops hypotheses on how social and economic contexts of immigrant reception after welfare reform influence naturalization behavior. Using General Social Survey (GSS) data and longitudinal data from the Survey of Program Dynamics (SPD) for 1988-2002, the research finds that hypotheses about the influence of the social context of reception, as reflected in state-level favorability of attitudes toward immigrants, are most consistently supported in the data. The results hold important implications for both theories of immigrant incorporation and ideas about what constitutes the most effective policy instruments to enhance the social and economic status of immigrants.

Classical assimilation theory postulates that over time, members of immigrant groups will develop more primary ties with native members of the host society. However, lack of data has led most research to rely on the study of either spatial mobility or other secondary variables as proxies of primary ties. Using data from the Multi-City Study of Urban Inequality, this research examines primary relations, comparing the number of cross-ethnic strong ties among foreign- and native-born generations of persons of Mexican origin in Los Angeles County. The fi ndings indicate that the native-born are substantially more likely to report cross-ethnic ties than immigrants. Spatial variables only partially explain the effect of primary structural assimilation, implying that both primary group and spatial dynamics play important roles in structural incorporation.

Changes in affirmative action policies in some states create possibilities for “natural experiments” to observe the effect of public policy on racial and ethnic inequality in American society. This study measured the impact of Initiative 200, a ballot measure that eliminated affirmative action in Washington State, on the transition from high school to college. As of 1999, the year after I-200 passed, the proportion of minority high school seniors who went to college in Washington State decreased temporarily. The impact of I-200 was registered almost entirely at the University of Washington, the flagship public institution in the state. This decrease, however, stemmed less from changes in minority admission rates than from declines in application rates. Affirmative action programs may provide a signal of an institutional “welcoming environment” that serves as a counterweight to the normal reluctance of prospective students to apply to institutions that may be perceived as intimidating. Although the impact of I-200 was short-lived, significant racial and ethnic differences remain in the transition from high school to college.

Cultivar and planting site are two factors that often receive minimal attention, but can have a significant impact on the quality of apple (Malus ×domestica) produced. A regional project, NE-183 The Multidisciplinary Evaluation of New Apple Cultivars, was initiated in 1995 to systematically evaluate 20 newer apple cultivars on Malling.9 (M.9) rootstock across 19 sites in North America. This paper describes the effect of cultivar and site on fruit quality and sensory attributes at a number of the planting sites for the 1998 through 2000 growing seasons. Fruit quality attributes measured included fruit weight, length: diameter ratio, soluble solids concentration (SSC), titratable acidity (TA), flesh firmness, red overcolor, and russet. Fruit sensory characteristics rated included crispness, sweetness, and juiciness, based on a unipolar intensity scale (where 1 = least and 5 = most), and acidity, flavor, attractiveness, and desirability based on a bipolar hedonic scale (where 1 = dislike and 5 = like extremely). All fruit quality and sensory variables measured were affected by cultivar. The two-way interaction of cultivar and planting site was significant for all response variables except SSC, TA, russet, crispness, and sweetness ratings. The SSC: TA ratio was strongly correlated with sweetness and acidity sensory rating, but was weakly correlated with flavor rating. The results demonstrate that no one cultivar is ideally suited for all planting sites and no planting site is ideal for maximizing the quality of all apple cultivars.

ADDITIONAL INDEX WORDS. postharvest physiology, storage, physiological disorder, Malus ABSTRACT. The activities and isoenzyme patterns of guaiacol-dependent peroxidase (POX), ascorbate peroxidase (APX), superoxide dismutase (SOD) and catalase (CAT) were studied in yellow- and red-fruited crab apple (Malus (L.) Mill.) selections from a 'White Angel∑ x 'Rome Beauty∑ cross that show differential susceptibility to the physiological storage disorder, superficial scald. There were no consistent relationships between total enzyme activities and scald incidence, high activities of the enzymes being detected in selections with both high and low susceptibilities to scald. However, ad- ditional individual isoforms of some antioxidant enzymes were detected in the scald-resistant selections when compared with scald-susceptible selections. In a native gel system, four guaiacol-dependent POX isoenzymes were detected in both yellow and red scald-resistant selections compared with only two in scald-susceptible selections. Similarly, for anodic acidic POX assayed using benzidine, six isoenzymes were detected in both yellow and red scald-resistant selections compared with five in yellow and four in red susceptible selections. Ten SOD isozymes were detected in scald-resistant yellow-fruited selections compared with only five faint bands in scald-susceptible selections, but similar patterns were not detectable for red-fruited selections. Differences in the presence of various isoenzymes for CAT and APX were also detected among the selections, but associations with scald susceptibility were also affected by fruit color or were inconsistent. The presence or absence of individual isoenzymes may be a better indication of scald resistance or susceptibility than the total enzyme activities. Isoenzyme analyses, especially of POX, could be useful to breeders for the early detection of scald resistance/ susceptibility in apples. The reactive oxygen species (ROS), hydrogen peroxide (H 2 O 2 ), singlet oxygen, superoxide (O 2 -), and hydroxyl (.OH) radicals, are recognized as important features of plant metabolism and in plant responses to stress (Halliwell and Gutteridge, 1989). While ROS are present in all plants in varying degrees as a result of normal metabolism, their levels in vivo depend on the balance between ROS production and the capacity of the cell to scavenge them. ROS, especially .OH, can react with all biological macromolecules causing lipid peroxidation as well as modification to the structure and function of proteins and nucleic acids (Bailly et al., 1996; Hal- liwell and Gutteridge, 1989). ROS induce the antioxidant defense system of low molecular weight antioxidants (Rao et al., 1996), and enzymes such as peroxidase (POX), catalase (CAT), ascorbate peroxidase (APX), superoxide dismutase (SOD) and glutathione reductase (GR) (Alscher et al., 2002; Bowler et al., 1992; Shigeoka et al., 2002). SOD dismutates O 2 - to H 2 O 2 and O 2 in a reaction that is spontaneous and extremely rapid (Van Camp et al., 1994), thus protecting the cells from damage by O 2 - reaction products. The product H 2 O 2 , which is also a potentially toxic compound, is then reduced to H 2 O by a number of enzymes such as POX, CAT, APX, and GR (Criessen et al., 1994). Although toxic in high con- centrations, ROS are also involved as early messenger molecules

The relationship between soluble peroxidase (EC 1.11.1.7; POX) activity and the development of a chilling-related disorder, superficial scald, was studied in three apple fruit (Malus x domestica Borkh.) systems: a White Angel x Rome Beauty population with progeny with different scald susceptibilities; Delicious from three harvests with progressively declining scald susceptibility; and the scald-resistant Idared and the scald-susceptible Law Rome. Differences in incidence and severity of scald in progeny from White Angel x Rome Beauty progeny tended to show relationships with POX activity at harvest, but, overall, associations were not consistent. However, greater scald incidence and lower POX activity were found in less mature Delicious fruit than in later harvested fruit. Also, the scald-resistant Iotadared had a much higher POX activity compared with the scald-susceptible Law Rome. A general hypothesis that POX activity is related to scald susceptibility was generally supported, but exceptions were observed.