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This study compares how different cow genotyping strategies increase the accuracy of genomic estimated breeding values (EBV) in dairy cattle breeds with low numbers. In these breeds, few sires have progeny records, and genotyping cows can improve the accuracy of genomic EBV. The Guernsey breed is a small dairy cattle breed with approximately 14,000 recorded individuals worldwide. Predictions of phenotypes of milk yield, fat yield, protein yield, and calving interval were made for Guernsey cows from England and Guernsey Island using genomic EBV, with training sets including 197 de-regressed proofs of genotyped bulls, with cows selected from among 1,440 genotyped cows using different genotyping strategies. Accuracies of predictions were tested using 10-fold cross-validation among the cows. Genomic EBV were predicted using 4 different methods: (1) pedigree BLUP, (2) genomic BLUP using only bulls, (3) univariate genomic BLUP using bulls and cows, and (4) bivariate genomic BLUP. Genotyping cows with phenotypes and using their data for the prediction of single nucleotide polymorphism effects increased the correlation between genomic EBV and phenotypes compared with using only bulls by 0.163 ± 0.022 for milk yield, 0.111 ± 0.021 for fat yield, and 0.113 ± 0.018 for protein yield; a decrease of 0.014 ± 0.010 for calving interval from a low base was the only exception. Genetic correlation between phenotypes from bulls and cows were approximately 0.6 for all yield traits and significantly different from 1. Only a very small change occurred in correlation between genomic EBV and phenotypes when using the bivariate model. It was always better to genotype all the cows, but when only half of the cows were genotyped, a divergent selection strategy was better compared with the random or directional selection approach. Divergent selection of 30% of the cows remained superior for the yield traits in 8 of 10 folds.

As of December 2015, 2,376 Guernsey bulls and cows had genotypes from collaboration between the United States, Canada, the United Kingdom, and the Isle of Guernsey. Of those, 439 bulls and 504 cows had traditional US evaluations, which provided sufficient data to justify investigation of the possible benefits of genomic evaluation for the Guernsey breed. Evaluation accuracy was assessed using a traditional 4-yr cutoff study. Twenty-two traits were analyzed (5 yield traits, 3 functional traits, and 14 conformation traits). Mean reliability gain over that for parent average was 16.8 percentage points across traits, which compares with 8.2, 18.5, 20.0, and 32.6 percentage points reported for Ayrshires, Brown Swiss, Jerseys, and Holsteins, respectively. Highest Guernsey reliability gains were for rump width (44.5 percentage points) and dairy form (40.5 percentage points); lowest gains were for teat length (1.9 percentage points) and rear legs (side view) (2.3 percentage points). Slight reliability losses (1.5 to 4.5 percentage points) were found for udder cleft, final score, and udder depth as well as a larger loss (13.6 percentage points) for fore udder attachment. Twenty-one single nucleotide polymorphisms were identified for Guernsey breed determination and can be used in routine genotype quality control to confirm breed and identify crossbreds. No haplotypes that affect fertility were identified from the current data set. Principal component analysis showed some divergence of US and Isle of Guernsey subpopulations. However, the overlap of US, Canadian, UK, and Isle of Guernsey subpopulations indicated the presence of gene flow, and the similarities in the subpopulations supports a common genomic evaluation system across the regions.

The objectives of this paper were to briefly review progress in the genetic evaluation of novel traits in Canada and the United States, assess methods to predict selection accuracy based on cow reference populations, and illustrate how the use of indicator traits could increase genomic selection accuracy. Traits reviewed are grouped into the following categories: udder health, hoof health, other health traits, feed efficiency and methane emissions, and other novel traits. The status of activities expected to lead to national genetic evaluations is indicated for each group of traits. For traits that are more difficult to measure or expensive to collect, such as individual feed intake or immune response, the development of a cow reference population is the most effective approach. Several deterministic methods can be used to predict the reliability of genomic evaluations based on cow reference population size, trait heritability, and other population parameters. To provide an empirical validation of those methods, predicted accuracies were compared with observed accuracies for several cow reference populations and traits. Reference populations of 2,000 to 20,000 cows were created through random sampling of genotyped Holstein cows in Canada and the United States. The effects of single nucleotide polymorphisms (SNP) were estimated from those cow records, after excluding the dams of validation bulls. Bulls that were first progeny tested in 2013 and 2014 were then used to carry out a validation and estimate the observed accuracy of genomic selection based on those SNP effects. Over the various cow population sizes and traits considered in the study, even the best prediction methods were found, on average, to either under-evaluate observed accuracy by 0.20 or over-evaluate it by 0.22, depending on the approach used to estimate the number of independently segregating chromosome segments. In some instances, differences between observed and predicted accuracies were as large as 0.47. Indicator traits can be very useful for the selection of novel traits. To illustrate this, protein yield, body weight, and mid-infrared data were used as indicator traits for feed efficiency. Using those traits in conjunction with 5,000 cow records for dry matter intake increased the reliability of genomic predictions for young animals from 0.20 to 0.50.

The effect on prediction accuracy for Jersey genomic evaluations of Danish and US bulls from using a larger reference population was assessed. Each country contributed genotypes from 1,157 Jersey bulls to the reference population of the other. Data were separated into reference (US only, Danish only, and combined US-Danish) and validation (US only and Danish only) populations. Depending on trait (milk, fat, and protein yields and component percentages; productive life; somatic cell score; daughter pregnancy rate; 14 conformation traits; and net merit), the US reference population included 2,720 to 4,772 bulls and cows with traditional evaluations as of August 2009; the Danish reference population included 635 to 996 bulls. The US validation population included 442 to 712 bulls that gained a traditional evaluation between August 2009 and December 2013; the Danish validation population included 105 to 196 bulls with multitrait across-country evaluations on the US scale by December 2013. Genomic predicted transmitting abilities (GPTA) were calculated on the US scale using a selection index that combined direct genomic predictions with either traditional predicted transmitting ability for the reference population or traditional parent averages (PA) for the validation population and a traditional evaluation based only on genotyped animals. Reliability for GPTA was estimated from the reference population and August 2009 traditional PA and PA reliability. For prediction of December 2013 deregressed daughter deviations on the US scale, mean August 2009 GPTA reliability for Danish validation bulls was 0.10 higher when based on the combined US-Danish reference population than when the reference population included only Danish bulls; for US validation bulls, mean reliability increased by 0.02 when Danish bulls were added to the US reference population. Exchanging genotype data to increase the size of the reference population is an efficient approach to increasing the accuracy of genomic prediction when the reference population is small.

Increased computing time for the ever-growing predictor population and linkage decay between the ancestral population and current animals have become concerns for genomic evaluation systems. The effects on reliability of US genomic evaluations from including cows and bulls in the Holstein predictor population and also from excluding older bulls from the predictor population were examined. Holstein data collected for December 2013 US genomic evaluations were used in cutoff studies to determine reliability gains, regression coefficients, and bias for 5 yield, 3 fitness, 2 fertility, and 18 conformation traits. Three predictor populations were examined based on animal sex: 30,852 cows with traditional evaluations as of August 2012, 21,883 bulls with traditional evaluations as of August 2012, and a combined group of all bulls and cows. Three subsets of the bull predictor population were examined to determine effect of age: bulls born before 1996 excluded (25% of bulls excluded), bulls born before 2001 excluded (50%), and bulls born before 2005 excluded (75%). The validation set for all predictor populations was either bulls or cows first receiving a traditional evaluation between August 2012 and December 2013. Across all traits, the addition of cows to the bull predictor population increased reliability gains by 0.4 percentage points for validation bulls and 4.4 points for validation cows. Across all traits, excluding bulls born before 1996 from the bull-only predictor population decreased gains in genomic reliability by 1.8 percentage points. For 19 of 28 traits, excluding bulls born before 2005 from the predictor population resulted in lower bias in genomic evaluations of validation bulls. Although the contribution of cows and older bulls to improved accuracy of US genomic evaluations is small, a plateau of achievable gain has not yet been reached.

Selection, mating, and improvement of dairy animals have required accurate pedigrees. Genomic tools allow paternal ancestors to be easily confirmed or discovered because most sires are genotyped for many markers, but maternal ancestors are more difficult to discover because most female ancestors are not genotyped. Three methods to discover maternal grandsires (MGS) were developed and compared. Conflicts were counted one single nucleotide polymorphism (SNP) at a time between genotypes of the animal and potential MGS (duo method) or also using the sire's genotype (trio method). Alternatively, haplotypes of a potential MGS were matched to the animal's maternal haplotype, obtained by using linkage across loci (HAP method). The duo and trio methods can be performed as soon as a genotype is received because no imputation is required. The HAP method improved accuracy because genotypes with 2,683 (3K) SNP were imputed to the 45,187 (50K) SNP used for genomic evaluation. The HAP method was tested using modified pedigrees with 5% of true MGS replaced by a random genotyped bull from the same birth year and 5% of MGS set to missing for 4,134 Holsteins, 552 Jerseys, and 142 Brown Swiss that had confirmed, genotyped sires. Those same animals were used to test the duo and trio methods, except that some animals had multiple genotypes and imputed dams were excluded. Accuracy measured how often the correct MGS was selected from among 12,152 genotyped Holstein, 2,265 Jersey, and 1,605 Brown Swiss potential MGS. Accuracies were 61, 60, and 65%, respectively, with the duo method; 95, 91, and 94% with the trio method; and 97, 95, and 97% with the HAP method. Accuracy of the duo method was poor (only 52% for animals genotyped with 3K and 65% with 50K) because additional information from the paternal genotype is not used. Accuracy of the trio method was 97% with 50K but only 78% with 3K because the missing SNP were not imputed. Accuracy of the HAP method was 94% with 3K genotypes, 98% with 50K, and 92% with nongenotyped, imputed dams. When the HAP method was extended to great-grandsires, the accuracy of maternal great-grandsire discovery was 92% for 652 Holsteins, 95% for 33 Jerseys, and 85% for 20 Brown Swiss. Accuracy was even higher using simulated genotypes. Because most dairy bulls over several generations have been genotyped, percentages of haplotypes shared with candidate males can accurately confirm, correct, or discover the sires, MGS, and even more distant ancestors of most animals.

The GeneSeek Genomic Profiler (GGP) BeadChip (GeneSeek, Lincoln, NE), which became available commercially in February 2012, is based on the Illumina BovineLD Genotyping BeadChip (Illumina Inc., San Diego, CA), with 1,745 additional single nucleotide polymorphisms (SNP) for genomic evaluation and SNP for proprietary single-gene tests. The BovineLD chip with 6,909 SNP, which replaced the Illumina GoldenGate Bovine3K Genotyping BeadChip, has been available since October 2011. The GGP's additional SNP for genomic evaluation were selected to improve imputation by filling SNP gaps on chromosomes and including more Bovine3K SNP than were on the BovineLD chip and to impute microsatellite alleles to facilitate parentage validation. The SNP for single-gene tests were included to minimize the number of separate tests required for those genes, particularly for bulls. The September 2012 US national genomic evaluation included genotypes from BovineLD and GGP chips for 82,510 animals. For those data, BovineLD and GGP performance was similar. The call rate for SNP on these chips that were used in genomic evaluation was 99.6%. The 9 Y-chromosome SNP in common on the BovineLD and GGP chips were highly effective in sex validation (call rate of 99% for males and 0.01% for females). For both chips, the rate of parent–progeny conflicts on a SNP basis (≤0.004%) was similar to that for SNP on the Illumina BovineSNP50 Genotyping BeadChip. Imputation accuracy for 45,187 BovineSNP50 SNP averaged 99.4% for Holsteins. Imputation accuracy was slightly higher for the GGP chip compared with the BovineLD chip because of its additional SNP. Reliability for genomic evaluations using BovineLD and GGP genotypes was 3 percentage points higher than that for Bovine3K genotypes.

Genomic evaluations using genotypes from the Illumina Bovine3K BeadChip (3K) became available in September 2010 and were made official in December 2010. The majority of 3K-genotyped animals have been Holstein females. Approximately 5% of male 3K genotypes and between 3.7 and 13.9%, depending on registry status, of female genotypes had sire conflicts. The chemistry used for the 3K is different from that of the Illumina BovineSNP50 BeadChip (50K) and causes greater variability in the accuracy of the genotypes. Approximately 2% of genotypes were rejected due to this inaccuracy. A single nucleotide polymorphism (SNP) was determined to be not usable for genomic evaluation based on percentage missing, percentage of parent-progeny conflicts, and Hardy-Weinberg equilibrium discrepancies. Those edits left 2,683 of the 2,900 3K SNP for use in genomic evaluations. The mean minor allele frequencies (MAF) for Holstein, Jersey, and Brown Swiss were 0.32, 0.28, and 0.29, respectively. Eighty-one SNP had both a large number of missing genotypes and a large number of parent-progeny conflicts, suggesting a correlation between call rate and accuracy. To calculate a genomic predicted transmitting ability (GPTA) the genotype of an animal tested on a 3K is imputed to the 45,187 SNP included in the current genomic evaluation based on the 50K. The accuracy of imputation increases as the number of genotyped parents increases from none to 1 to both. The average percentage of imputed genotypes that matched the corresponding actual 50K genotypes was 96.3%. The correlation of a GPTA calculated from a 3K genotype that had been imputed to 50K and GPTA from its actual 50K genotype averaged 0.959 across traits for Holsteins and was slightly higher for Jerseys at 0.963. The average difference in GPTA from the 50K- and 3K-based genotypes across trait was close to 0. The evaluation system has been modified to accommodate the characteristics of the 3K. The low cost of the 3K has greatly increased genotyping of females. Prior to the availability of the 3K (August 2010), female genotyping accounted for 38.7% of the genotyped animals. In the past year, the portion of total genotypes from females across all chip types rose to 59.0%.

Genomic evaluations are calculated using deregressed predicted transmitting abilities (PTA) from traditional evaluations to estimate effects of single nucleotide polymorphisms. The direct genomic value (sum of an animal's marker effects) should be consistent with traditional PTA, which is the case for bulls. However, traditional PTA of yield traits (milk, fat, and protein) for genotyped cows are higher than their direct genomic values. To ensure that characteristics of cow PTA for yield traits were more similar to those for bull PTA, mean and variance of cow Mendelian sampling (PTA minus parent average) were adjusted to be similar to those of bulls. The same adjustments were used for all genotyped cows in a breed. To determine gains in reliabilities, predictions were made for bulls with August 2010 evaluations that did not have traditional evaluations in August 2006. By adjusting cow PTA and parent averages of genotyped animals, Holstein and Jersey regressions of August 2010 deregressed PTA on genomic evaluations based on August 2006 data became closer to 1 for the adjusted predictor population compared with the unadjusted predictor population. Evaluation bias was decreased for Holsteins when the predictor population was adjusted. Mean gain in reliability over parent average increased 3.5 percentage points across yield traits for Holsteins and 0.9 percentage points for Jerseys when the predictor population was adjusted. The accuracy of genomic evaluations for Holsteins and Jerseys was increased through better use of information from cows.

Two methods of testing predictions from genomic evaluations were investigated. Data used were from the August 2006 and April 2010 official USDA genetic evaluations of dairy cattle. The training data set consisted of both cows and bulls that were proven (had own or daughter information) as of August 2006 and included 8,022, 1,959, and 1,056 Holsteins, Jerseys, and Brown Swiss, respectively. The validation data set consisted of bulls that were unproven as of August 2006 and were proven by April 2010 with 2,653, 411, and 132 Holsteins, Jerseys, and Brown Swiss for the production traits. Method 1 used the training animal's predicted transmitting ability (PTA) from August of 2006. Method 2 used the training animal's April 2010 PTA to estimate single nucleotide polymorphism effects. Both methods were tested using several regressions with the same validation animals. In both cases, the validation animals were tested using the deregressed April 2010 PTA. All traits that had genomic evaluations from the official USDA April 2010 genetic evaluations were tested. Results included bias, differences from expected regressions (calculated using selection intensities), and the coefficients of determination. The genomic information increased the predictive ability for most of the traits in all of the breeds. The 2 methods of testing resulted in some differences that would affect interpretation of results. The coefficient of determination was higher for all traits using method 2. This was the expected result as the data were not independent because evaluations of the validation bulls contributed to their sires' evaluations. The regression coefficients from method 2 were often higher than the regression coefficients from method 1. Many traits had regression coefficients that were higher than 2 standard deviations from the expected regressions when using method 2. This was partially due to the lack of independence of the training and validation data sets. Most traits did have some level of bias in the prediction equations, regardless of breed. The use of method 1 made it possible to evaluate the increased accuracy in proven first-crop bull evaluations by using genomic information. Proven first-crop bulls had an increase in accuracy from the addition of genomic information. It is advised to use method 1 for validation of genomic evaluations.

To facilitate routine genomic evaluation, a database was constructed to store genotypes for 50,972 single nucleotide polymorphisms (SNP) from the Illumina BovineSNP50 BeadChip (Illumina Inc., San Diego, CA). Multiple samples per animal are allowed. All SNP genotypes for a sample are stored in a single row. An indicator specifies whether the genotype for a sample was selected for use in genomic evaluation. Samples with low call rates or pedigree conflicts are designated as unusable. Among multiple samples that qualify for use in genomic evaluation, the one with the highest call rate is designated as usable. When multiple samples are stored for an animal, a composite is formed during extraction by using SNP genotypes from other samples to replace missing genotypes. To increase the number of SNP available, scanner output for approximately 19,000 samples was reprocessed. Any SNP with a minor allele frequency ofor = 1% for Holsteins, Jerseys, or Brown Swiss was selected, which was the primary reason that the number of SNP used for USDA genomic evaluations increased. Few parent-progeny conflicts (or = 1%) and a high call rate (or = 90%) were additional requirements that eliminated 2,378 SNP. Because monomorphic SNP did not degrade convergence during estimation of SNP effects, a single set of 43,385 SNP was adopted for all breeds. The use of a database for genotypes, detection of conflicts as genotypes are stored, online access for problem resolution, and use of a single set of SNP for genomic evaluations have simplified tracking of genotypes and genomic evaluation as a routine and official process.

GeneSeek (Neogen Corp., Lexington, KY) designed a new version of the GeneSeek Genomic Profiler HD BeadChip for Dairy Cattle, which originally had >77,000 single nucleotide polymorphisms (SNP). A set of >140,000 SNP was selected that included all SNP on the existing GeneSeek chip, all SNP used in US national genomic evaluations, SNP that were possible functional mutations, and other informative SNP. Because SNP with a lower minor allele frequency might track causative variants better, 30,000 more SNP were selected from the Illumina BovineHD Genotyping BeadChip (Illumina Inc., San Diego, CA) by choosing SNP to maximize differences in minor allele frequency between a SNP being considered for the new chip and the 2 SNP that flanked it. Single-gene tests were included if their location was known and bioinformatics indicated relevance for dairy cattle. To determine which SNP from the new chip should be included in genomic evaluations, genotypes available from chips already in use were used to impute and evaluate the SNP set. Effects for 134,511 usable SNP were estimated for all breed-trait combinations; SNP with the largest absolute values for effects were selected (5,000 for Holsteins, 1,000 for Jerseys, and 500 each for Brown Swiss and Ayrshires for each trait). To increase overlap with the 60,671 SNP currently used for genomic evaluation, 12,094 more SNP with the largest effects were added. After removing SNP with many parent-progeny conflicts, 84,937 SNP remained. Three cutoff studies were conducted with 3 SNP sets to determine reliability gain over that for parent average when evaluations based on August 2011 data were used to predict December 2014 performance. Across all traits, mean Holstein reliability gains were 32.5, 33.4, and 32.0 percentage points for 60,671, 84,937, and 134,511 SNP, respectively. After genotypes from the new chip became available, the proposed set was reduced from 84,937 to 77,321 SNP to remove SNP that were not included during manufacture, reduce computing time, and improve imputation performance. The set of 77,321 SNP was evaluated using August 2011 data to predict April 2015 performance. Reliability gain over 60,671 SNP was 1.4 percentage points across traits for Holsteins. Improvement over 84,937 SNP was partially the result of 4mo of additional data and genotypes from the new chip. Revision of the SNP set used for genomic evaluation is expected to be an ongoing process to increase evaluation accuracy.

A method was developed to calculate preliminary genomic evaluations daily or weekly before the release of official monthly evaluations by processing only newly genotyped animals using estimates of single nucleotide polymorphism effects from the previous official evaluation. To minimize computing time, reliabilities and genomic inbreeding are not calculated, and fixed weights are used to combine genomic and traditional information. Correlations of preliminary and September official monthly evaluations for animals with genotypes that became usable after the extraction of genotypes for August 2014 evaluations were >0.99 for most Holstein traits. Correlations were lower for breeds with smaller population size. Earlier access to genomic evaluations benefits producers by enabling earlier culling decisions and genotyping laboratories by making workloads more uniform across the month.

In this work we present the highest frequency performance reported to date of an AlInN/GaN HEMT with a 2×150 μm configuration. The frequency performance reached was of a measured fT of 107 GHz and an fmax of 89.5 GHz. The device has an IDSS of 1.1 A/mm at a VGS of 0 V, an Imax of 1.3 A/mm at VGS of 1 V, and a gm-peak of 395 mS/mm. The gate length, LG, was 122 nm and a total barrier thickness, tbar, of 10.1 nm. This gives us an LG/tbar ratio of 12.1 with a high ft·LG product of 13 GHz·μm. The thin barrier thickness greatly contributed to the high frequency performance of the device by reducing the short channel effects. The contact resistance of a TLM structure next to the tested device is 0.42 Ω·mm. The epitaxial layer was grown by MOCVD on a 3” SiC substrate. Hall measurements, after passivation, revealed an average material sheet resistance, Rsheet, of 219 Ω/□, a sheet carrier concentration of 2.2×1013cm-2, and a mobility of 1320 cm2/V-s. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We report the first CW Ka-band radio-frequency (RF) power measurements at 35 GHz from a passivated Al0.82In0.18N/GaN high-electron mobility transistor on SiC with 9.8-nm-thin barrier. This device delivered a maximum of 5.8 W/mm with a power-added efficiency of 43.6% biased at VDS = 20 V and 10% IDSS when matched for power at CW. The device was grown by metal-organic chemical vapor deposition with 2.8-?m source-drain spacing and a gate length of 160 nm. An excellent ohmic contact was obtained with an Rc of 0.62 ?·mm. The maximum extrinsic transconductance was 354 mS/mm with an IDSS of 1197 mA/mm at a VGS of 0 V, an ft of 79 GHz, and an fmax of 113.8 GHz.

HU93030-007 LCF (65o01.39 0 N and 30o14.81 0 W) is a 4.5 m long, giant (11 cm diameter) piston core from 1800 m water depth on the continental slope, south of the Denmark Strait sill. The core sampled acoustically stratified sediments at a site below the Kangerlussuaq Trough. Nine AMS 14 C dates on planktic foraminifera indicate that the core spans 14 to 28 14 C ka. The sediments consists of two principal lithofacies: Lithofacies I (LI) comprises tan=ochre intervals with abundant ice-rafted sandstone=siltstone clasts larger than 2 mm and with an average thickness of 47 cm; it is also associated with peaks in carbonate content and TOC%. Lithofacies II (LII) consists of fine-grained, dark gray, hemipelagic sediment. There are three distinct intervals of LI dated between 14.3 and 15.5 (LIc), 20.1 and 21.9 (LIb), 24.7 and 25.8 (LIa) ka. The ages suggest that deposition of LI is approximately coeval with Heinrich events 1 and 2 in the North Atlantic, whereas LIa appears younger than H-3. Lithofacies I is derived from far-travelled ice bergs from an unknown source, but not from the northeastern Laurentide Ice Sheet. Stable isotope studies on Neogloboquadrina pachydermasinistral show little evidence for significant meltwater events associated with LI, but surprisingly, light oxygen isotopic events are present in the benthic foraminiferal analyses (Cibicidoides wuellerstorfiand Melonis zaandamae). The ages of the HU93030-007 iceberg-rafted detritus (IRD) events are similar to IRD peaks in cores north of Denmark Strait, on the East Greenland slope. HU87033-009 LCF (SE Baffin slope, 62o30.99 0 N and 59o26.82 0 W, 1437 m wd) is situated in a similar position to HU93030-007 but with respect to the Laurentide Ice Sheet; its d 18 O record on planktic foraminifera is virtually identical to that of HU93030-007. The timing of IRD events is similar in both these cores between 14 and 30 ka. H-3 may be present in HU87033-009 as an IRD event, but in contrast to H-1 and H-2, it is not evident as a discernible detrital carbonate event. © 1998 Elsevier Science B.V. All rights reserved.

The National Environmental Policy Act (NEPA) of 1969 and the Council on Environmental Quality (CEQ) regulations in the United States require federal agencies to apply an environmental impact assessment (EIA) in decision-making related to their actions. One aspect requires an examination of direct, indirect and cumulative impacts (CIs). Historically, cumulative impact assessment (CIA) has been given limited attention in EIA and resultant environmental impact statements (EISs), not because of its lack of importance, but owing to limitations in methodologies and procedures, including documentation consistency. The objectives of this study were to identify deficiencies in the documentation of CIs and CIA in EISs and to formulate appropriate recommendations (potential solutions) related to such deficiencies. The study involved the systematic review of 33 EISs (11 each from the U.S. Department of Agriculture: Forest Service, the U.S. Army Corps of Engineers, and the U.S. Department of Transportation: Federal Highway Administration). The results indicate that improvements have been made in documentation practices since 1990; however, inconsistencies and inadequacies still exist. Therefore, the following recommendations were developed: (1) CIs should be reported in a separate part of the “Environmental Consequences” section, and they should be addressed for each pertinent environmental resource; (2) a summary of CIs should be included; (3) any CIs considered not significant should be mentioned plus the reason(s) for their non-significance; (4) spatial and temporal boundaries addressed within the CIA process should be defined for pertinent environmental resources; and (5) utilized guidelines and methodologies should be described.

Twelve 1–2 m, 10-cm-diameter gravity cores collected in 1988 and 1991, from the continental shelf and fjords of East Greenland near Kangerlussuaq Fjord/Trough (ca. 68°N, 32°W), have distinct changes in lithofacies and in the quantity of iceberg rafted (IRD) sediments. These changes are readily observed in X-radiographs of the split cores. We quantify the IRD contribution through grain-size analyses and counting the number of clasts >2 mm from the X-radiographs. Chronological control is provided by acclerated mass spectroscopy 14C dates on foraminifera. During deglaciation, after 14 cal.ka there was one interval of IRD accumulation ca. 12–13 cal.ka, followed by a brief return to IRD conditions centred at 9 cal.ka. Thereafter, a prominent feature of most cores on the shelf is an increase in IRD accumulation that started ca. 5–6 cal.ka, and which has increased toward the present. Indicators of iceberg rafting, such as the net sand flux and numbers of clasts >2 mm ka−1, follow a power law distribution when graphed against distance from the present East Greenland coast, a measure of the position of the glacier margins. The form of the relationship indicates that there is a dramatic decrease in the supply of sediment from the fjords to the shelf. These relationships are used to estimate changes in the location of the ice margin during the late Quaternary based on a site on the East Greenland slope, Denmark Strait, and to discuss factors that can negate such a simple transfer function. © 1997 by John Wiley & Sons Ltd.

A stochastic modelling approach has been used to assess the uncertainty in predictions of contaminant migration in geological media surrounding a hypothetical buried waste repository in Bedfordshire, UK. In Part 1 of this two-part paper, the physical setting and the development of the conceptual and numerical models for groundwater flow and transport are described. In this part, the development of the stochastic modelling approach and the analysis of the set of Monte Carlo experiments used to characterise the uncertainty in the migration pathways are presented. Eleven Monte Carlo experiments have been performed. Nine have been undertaken to evaluate the effect of uncertainty in the parameters of the geostatistical model of hydraulic conductivity of the principal aquifer, and two have been performed to examine the influence of the location of the repository release zone. The study has demonstrated the use of the stochastic modelling approach in probabilistic risk assessments of the potential hazards arising from the burial of wastes.

The aim of this study is to illustrate the contribution that geostatistical techniques can make to risk assessment for buried waste repositories. For a hypothetical repository site in Bedfordshire, UK, multiple realisations of the hydraulic properties of the principal aquifers are constructed. For each realisation a numerical model describing the groundwater flow regime at the site is used to predict a possible pattern of migration based on the available hydrogeological data. A statistical analysis of the results is carried out to provide quantitative measures of the uncertainty in the patterns of migration deriving from a lack of knowledge of the media properties. In the first part of this two-part paper, the formulation of the conceptual and numerical models describing the regional groundwater flow regime is presented. A detailed assessment of the site has been undertaken to determine the principal hydrogeological formations within which contaminant migration would occur and the principal controls governing regional groundwater flow and contaminant transport. From the resulting conceptual model a quasi-three-dimensional groundwater flow and transport model has been developed. Part 2 of the paper describes the simulation experiments carried out using this model and the analysis of the results.

The East Greenland continental margin between c.66 and 68° N consists of a major fjord/trough system that extends from Kangerdlugssuaq Fjord, along Kangerdlugssuaq Trough to Denmark Strait. Measurements of the temperature and salinity of the water column along this transect indicates that ‘warm’ water (0–2°C) underlies the surface Polar Water of the East Greenland Current. A series of short (1–3 m) gravity cores along the fjord/trough transect have sufficient numbers of foraminifera that a suite of AMS 14C dates has been obtained, including both basal and core-top age estimates. Rates of sediment accumulation vary through space and time; over the last 1 ka estimates vary from c. 3 to 0.1 m. These dates and measurements of sediment density, together with measurements of the percentages by weight of total organic carbon and biogenic silica, are used to show graphs of fluxes of the organic and inorganic sediment components over the last 1–14 ka. An analysis of the net flux of foraminifera indicates a reduction in numbers during the Younger Dryas chronozone and a general similarity with data from the Renland (East Greenland) ice core data.

This chapter describes the present status of plastic packaging materials and technology employed in the food, beverage and other fast-moving consumer goods industries. This includes current types of packaging polymers used and advances and future trends in plastic packaging materials; water-soluble packaging; high performance barrier films; packaging coatings and additives, including clarifiers and scavenger systems; rigid, thin-wall and flexible packaging; pouch packaging; packaging sustainability; and current mechanical recycling systems.

This chapter discusses the current situation, developments and future trends in the use of biodegradable and biobased plastics in packaging for food, beverages and other fast-moving consumer items. Areas covered include the production, properties and processing of the various types of biodegradable polymer used for packaging, biobased versions of conventional polymers used in packaging and developments in the synthesis of monomers, chemicals and polymers by biobased routes. Particular emphasis is given to biobased polyethylene, polypropylene and polyethylene terepthalate. Definitions and standards of bioplastics, biodegradability, compostability and biobased content are also discussed.

Call rates on both a single nucleotide polymorphism (SNP) basis and an animal basis are used as measures of data quality and as screening tools for genomic studies and evaluations of dairy cattle. To investigate the relationship of SNP call rate and genotype accuracy for individual SNP, the correlation between percentages of missing genotypes and parent-progeny conflicts for each SNP was calculated for 103,313 Holsteins. Correlations ranged from 0.14 to 0.38 for the BovineSNP50 and BovineLD (Illumina Inc., San Diego, CA) and GeneSeek Genomic Profiler (Neogen Corp., Lincoln, NE) chips, with lower correlations for newer chips. For US genomic evaluations, genotypes are excluded for animals with a call rate of90% across autosomal SNP or80% across X-specific SNP. Mean call rate for 220,175 Holstein, Jersey, and Brown Swiss genotypes was 99.6%. Animal genotypes with a call rate of ≤99% were examined from the US Department of Agriculture genotype database to determine how genotype call rate is related to accuracy of calls on an animal basis. Animal call rate was determined from SNP used in genomic evaluation and is the number of called autosomal and X-specific SNP genotypes divided by the number of SNP from that type of chip. To investigate the relationship of animal call rate and parentage validation, conflicts between a genotyped animal and its sire or dam were determined through a duo test (opposite homozygous SNP genotypes between sire and progeny; 1,374 animal genotypes) and a trio test (also including conflicts with dam and heterozygous SNP genotype for the animal when both parents are the same homozygote; 482 animal genotypes). When animal call rate was ≤ 80%, parentage validation was no longer reliable with the duo test. With the trio test, parentage validation was no longer reliable when animal call rate was ≤ 90%. To investigate how animal call rate was related to genotyping accuracy for animals with multiple genotypes, concordance between genotypes for 1,216 animals that had a genotype with a call rate of ≤ 99% (low call rate) as well as a genotype with a call rate of99% (high call rate) were calculated by dividing the number of identical SNP genotype calls by the number of SNP that were called for both genotypes. Mean concordance between low- and high-call genotypes was99% for a low call rate of90% but decreased to 97% for a call rate of 86 to 90% and to 58% for a call rate of60%. Edits on call rate reduce the use of incorrect SNP genotypes to calculate genomic evaluations.

Traditional evaluations of cows with genotypes have been adjusted since April 2010 to be comparable with evaluations of bulls so that their value for estimation of single nucleotide polymorphism effects in genomic evaluation programs would be improved. However, that adjustment made them not comparable with traditional evaluations of nongenotyped cows. To create an adjustment for all cows with an evaluation based on US data, Mendelian sampling, which is the difference between predicted transmitting ability (PTA) and parent average (PA), was calculated for milk, fat, and protein yields and divided by a deregression factor. Standard deviations for the deregressed Mendelian sampling (DMS) were grouped by reliability with PA contribution removed (REL(no PA)). A multiplicative adjustment to reduce the DMS standard deviation for cows so that it would be the same as for bulls with similar REL(no PA) was represented as a linear function of REL(no PA). Mean cow PA by birth year was subtracted from individual bull and cow PA to create within-year PA deviation groups, and mean DMS was calculated by PA deviation group. Means decreased for bulls and increased for cows with increasing deviation. The differences were fit by linear regression on PA deviation and used to adjust cow DMS. The adjustment reduced PTA of cows with a high PA and increased PTA of cows with a low PA but did not change estimated genetic trend because adjustment was within birth year. The adjustment also reduced variance of cow evaluations within birth year. Traditional evaluations of genotyped cows with a REL(no PA) of ≥55% were further adjusted so that the difference between those evaluations and direct genomic values calculated using only bulls as predictors was similar to that for bulls. The second adjustment was small compared with a 2010 adjustment and, therefore, had little effect on the comparability of evaluations for genotyped and nongenotyped cows. Cows with converted evaluations from other countries were excluded from the predictor population, and their converted evaluations were adjusted so that the difference between their mean PTA and direct genomic value was the same as the corresponding difference for bulls. For cows with converted evaluations, the adjustment amount differed depending on REL(no PA) (55% or ≥55%). The new adjustment was implemented by USDA in April 2011 and permits a fairer comparison of estimated genetic merit between nongenotyped and genotyped cows.

Implementation of genomic evaluation has caused profound changes in dairy cattle breeding. All young bulls bought by major artificial insemination organizations now are selected based on such evaluation. Evaluation reliability can reach approximately 75% for yield traits, which is adequate for marketing semen of 2-yr-old bulls. Shortened generation interval from using genomic evaluations is the most important factor in increasing the rate of genetic improvement. Genomic evaluations are based on 42,503 single nucleotide polymorphisms (SNP) genotyped with technology that became available in 2007. The first unofficial USDA genomic evaluations were released in 2008 and became official for Holsteins, Jerseys, and Brown Swiss in 2009. Evaluation accuracy has increased steadily from including additional bulls with genotypes and traditional evaluations (predictor animals). Some of that increase occurs automatically as young genotyped bulls receive a progeny test evaluation at 5 yr of age. Cow contribution to evaluation accuracy is increased by decreasing mean and variance of their evaluations so that they are similar to bull evaluations. Integration of US and Canadian genotype databases was critical to achieving acceptable initial accuracy and continues to benefit both countries. Genotype exchange with other countries added predictor bulls for Brown Swiss. In 2010, a low-density chip with 2,900 SNP and a high-density chip with 777,962 SNP were released. The low-density chip has increased greatly the number of animals genotyped and is expected to replace microsatellites in parentage verification. The high-density chip can increase evaluation accuracy by better tracking of loci responsible for genetic differences. To integrate information from chips of various densities, a method to impute missing genotypes was developed based on splitting each genotype into its maternal and paternal haplotypes and tracing their inheritance through the pedigree. The same method is used to impute genotypes of nongenotyped dams based on genotyped progeny and mates. Reliability of resulting evaluations is discounted to reflect errors inherent in the process. Further increases in evaluation accuracy are expected because of added predictor animals and more SNP. The large population of existing genotypes can be used to evaluate new traits; however, phenotypic observations must be obtained for enough animals to allow estimation of SNP effects with sufficient accuracy for application to the general population.

Critically examines a number of issues related to the management of emerging software technologies. Some working guidelines are provided. It is recommended that any management process used be measured and consistently analyzed to improve one's competitive edge. In the area of metrics for managing object technology, there is an almost total lack of information. The current focus of the Consortium for the Management of Emerging Software Technologies (COMSOFT) is an object-oriented technology and the related area of software reuse. The new environment must be implemented piecemeal and frequently structures and procedures must be implemented that are only operational bridges, because during the transition two operational methodologies and philosophies will exist. >

It is generally agreed upon in the expert system development community that the maintenance problems associated with rule-based programming are in many respects different from those in traditional programming. Lacking a methodology and automated tools, maintenance of complex rule-based systems becomes very difficult without thorough knowledge of the design and structure of the entire system. SEAR is an advanced development project focused on exploring CASE technology to address these problems. This paper describes the SEAR tool suite. These tools support various stages of development including design through rapid prototyping, transition from prototype to production system, and ongoing enhancements and maintenance. >

Bovine Progressive Degenerative Myeloencephalopathy (Weaver Syndrome) is a recessive neurological disease that has been observed in the Brown Swiss cattle breed since the 1970’s in North America and Europe. Bilateral hind leg weakness and ataxia appear in afflicted animals at 6 to 18 months of age, and slowly progresses to total loss of hind limb control by 3 to 4 years of age. While Weaver has previously been mapped to Bos taurus autosome (BTA) 4∶46–56 Mb and a diagnostic test based on the 6 microsatellite (MS) markers is commercially available, neither the causative gene nor mutation has been identified; therefore misdiagnosis can occur due to recombination between the diagnostic MS markers and the causative mutation. Analysis of 34,980 BTA 4 SNPs genotypes derived from the Illumina BovineHD assay for 20 Brown Swiss Weaver carriers and 49 homozygous normal bulls refined the Weaver locus to 48–53 Mb. Genotyping of 153 SNPs, identified from whole genome sequencing of 10 normal and 10 carrier animals, across a validation set of 841 animals resulted in the identification of 41 diagnostic SNPs that were concordant with the disease. Except for one intergenic SNP all are associated with genes expressed in nervous tissues: 37 distal to NRCAM, one non-synonymous (serine to asparagine) in PNPLA8, one synonymous and one non-synonymous (lysine to glutamic acid) in CTTNBP2. Haplotype and imputation analyses of 7,458 Brown Swiss animals with Illumina BovineSNP50 data and the 41 diagnostic SNPs resulted in the identification of only one haplotype concordant with the Weaver phenotype. Use of this haplotype and the diagnostic SNPs more accurately identifies Weaver carriers in both Brown Swiss purebred and influenced herds.

ABSTRACT This paper describes a safe isolation technique for gas pipelines to enable construction activities, without complete decommissioning and recommissioning, The technique can be applied to valve installation or replacement, bypass of structures or platforms, and modifications such as to tie-in of pipelines to existing gas systems. This paper will examine the development and use of a technique employed on three major North Sea Projects since 1989, namely the High Differential Pig Train. INTRODUCTION Since 1989, activity in the area of localised pipeline isolation in the North Sea has increased dramatically, especially for the installation of topsides am. subsea emergency shutdown valves. In April 1989 Total oil Marine PIC (TCM) commissioned a study to evaluate isolation systems which net the Company' s isolation philosophy and would be available for an August shutdown to replace pipeline riser emergency shutdown valves. From the results of the study and from other Operator's experiences TCM were not satisfied that a completely safe isolation system was readily available. Options available were:Completely decommission pipelinecancel proposed shutdownDevelop a safe isolation technique in 6 weeks Option C was preferred since option A would involve unacceptable loss of production and option B would leave unacceptable isolation valves in service. As a result of McKenna and Sullivan's (M & S) experience in pipeline isolation and commissioning TCM developed jointly with M& S a technique which net the Company philosophy within 6 weeks. This technique has since been successfully deployed on numerous North sea Projects. The parameters for design were based on creating a safe work environment for hot and cold work to:–provide a safe isolation for construction activities–provide the ability to monitor pipeline conditions–minimise recommissioning problems associated with the introduction of water into gas pipelines–comply with Governmental Safety and Guidance notes The technique developed was based on using modified bi-directional pigs to from an isolating system capable of withstanding suitable differential pressures without moving and providing the necessary sealing to act as an interface barrier between inventory gas and the worksite. The isolation technique resulted in reduced production outage and lower construction costs compared to full pipeline decommissioning / recommissioning. This paper outlines the development and use of the technique on three TCM projects on the Alwyn and Frigg Gas Transportation system (see Figure 1). Project 1 : 1989 CHANGEOUT OF TOPSIDES ESDV?S (Emergency Shutdown Valves) TCM developed with M&S an isolation system which consisted of two parts:Part 1 Primary Pipeline Isolation to allow cold cuttingPart 2 secondary Riser Isolation to allow Welding Part 1 Primary pipeline Isolation Pipeline isolation, after depressurisation but not degassing, was accomplished in each Riser using a series of bi-directional pigs separated by slugs of nitrogen, gelled diesel and diesel forming a pig train (figure 2) referred to as Primary Dynamic Seal (PDS).

Electron spectroscopy, especially X-ray photoelectron spectroscopy, is generally regarded as a “slow” analytical technique, i.e. although the relative concentrations of the elements are relatively high (> 0.1 %) the acquisition of the data may take several hours. Furthermore the fact that the acquisition time may be long increases the chances of radiation damage and chemical change in sensitive materials such as organics and polymers. Any accessory which reduces the acquisition time for a given incident flux in both XPS and Auger electron spectroscopy, is to be welcomed. In this paper a multidetector system is described and a brief application to a radiation sensitive material is outlined.

Two series of silica-supported vanadium oxide catalysts were prepared by adsorption-hydrolysis of VOCl 3 on OH groups of silica and by impregnation with aqueous vanadyl oxalate complex. They were studied and characterised by TG, XRD, TEM, IR, XPS and O 2 chemisorption on partially reduced catalysts at -196°C. This information was correlated with the catalytic activity in the reaction of the oxidation of propylene in the presence of steam. The catalysts, containing 0-8 wt% V 2 O 5 , were found to contain vanadium oxide in a very high degree of dispersion, mainly as a monolayer. In catalysts prepared by impregnation with vanadyl oxalate, XPS and IR spectra showed that V 4+ species were predominant while the V 5+ species was in the majority when the adsorption-hydrolysis of VOCl 3 procedure was used. Catalyst activity appeared to be related to the presence of reduced vanadium oxide. Possible causes for the selectivity differences between phases in both series of catalysts are discussed.

Four basic methods which allow XPS analysis of selected areas (SAXPS) of less than 1 mm2 are described. Within the four sets there are occasionally several subsets and each of these will be briefly outlined and some aspects of the information theory given. Some methods are suitable for direct microscopy whilst others will depend on specimen translation. The advantages and disadvantages of SAXPS compared with other localised methods of surface analysis such as scanning Auger microscopy and ion microbeam SIMS are presented in tabular form.