Response Surface Designs Robust against Nuisance Factors

This paper discusses an algorithmic approach to constructing trend-free and orthogonally-blocked response surface designs. The constructed designs have the main effects, 2-factor interactions and second-order effects being orthogonal or near-orthogonal to the nuisance factors such as the time-trend or the blocking factors. The paper also provides a catalogue of (near-) trend-free Box–Behnkens designs and orthogonally blocked Box–Behnkens designs arranged in rows and columns.

Are There Differences and Complementarities between Senior and Young Entrepreneurs? An Intergenerational Perspective

Social exclusion related to the unemployment of vulnerable population groups constitutes a crucial limitation to achieving a sustainable world. In particular, young and senior populations have specific characteristics that put them at risk of exclusion from the labor market. This circumstance has motivated an attempt to foster cooperation between these age groups to enable them to develop entrepreneurial initiatives that will contribute to close this social vulnerability gap. We approach this topic by focusing on intergenerational entrepreneurship, understood as entrepreneuring projects jointly undertaken by seniors and young adults. The objective of this study was to identify the differences and complementarities between senior and young entrepreneurs with a view to enabling them to develop viable intergenerational entrepreneurial projects, with special emphasis in the motivational push, pull, and blocking factors that affect them. This kind of entrepreneurial initiative fosters knowledge transfer and experience between age groups, promotes job creation and social inclusion, improves a sense of belonging, and, thus, contributes to the construction of a stronger society serving as an engine for sustainable development. Therefore, intergenerational entrepreneurship can be considered a form of social innovation. A mixed-methods approach was utilized in this study, using quantitative data from a questionnaire as a starting point for the characterization and identification of senior and young entrepreneurial profiles, and qualitative data from focus groups, which enabled us to identify complementarities among generations. The results show that there are significant differences between youths and seniors in terms of the motivations and factors that push, pull, or block the decision to form an intergenerational entrepreneurial partnership. These differences can be interpreted as complementarities that can boost intergenerational cooperation to promote social inclusion.

The Effects of LIT and MLR-Bf on Immune Biomarkers and Pregnancy Outcomes in Women With Previous Early Recurrent Miscarriage: A Retrospective Study

Background: Immunological failure during pregnancy is considered one of the etiologies of recurrent miscarriage (RM). The decreased production of mixed lymphocyte reaction-blocking factors (MLR-Bf) may play a major role in this condition. Lymphocyte immunotherapy (LIT), which induces the production of MLR-Bf, has been used in treating RM patients since 1984. However, the effectiveness of LIT is currently being heatedly debated. In addition to that, possible changes to the maternal immune system upon induced MLR-Bf production by LIT remains unclear.Objectives: To explore the possible impacts that MLR-Bf may have on the expression of immune biomarkers and pregnancy outcomes, and deduce whether the prevention of miscarriages is possible with LIT or MLR-Bf in RM patients.Materials and Methods: Women with previous early RM (eRM) were enrolled in this retrospective study after they got pregnant again. LIT was implemented before pregnancy and during the first trimester. MLR-Bf and immune biomarkers were checked as the clinical routine. Patients were followed up until 12 gestational weeks. Levels of immune biomarkers and successful pregnancy rates were compared between MLR-Bf− group and MLR-Bf+ group stratified by LIT. Independent associations between LIT, or MLR-Bf, and miscarriage were estimated. All data management and analysis were conducted using SPSS 20.0.Results: A total of 1,038 patients, 497 MLR-Bf− (49 cases accepted LIT), and 541 MLR-Bf+(463 cases induced by LIT) were included in the study. Percentage of lymphocytes, the ratio of CD4+ T cells/lymphocytes, and levels of some rheumatoid biomarkers (anti-U1-nRNP, anti-SAA-52kd, and anti-CENOP B) were statistically higher in MLR-Bf+ group than in MLR-Bf− group among women without LIT. With LIT treatment the successful pregnancy rate was statistically higher in MLR-Bf+ group than in MLR-Bf− group (66.7% vs. 51.0%, P = 0.028) among women with LIT. Meanwhile, LIT was estimated to have an independent negative association with miscarriage.Conclusion: Upon LIT treament levels of immune biomarkers were different in women with and without MLR-Bf when stratified by whether they received LIT. Not MLR-Bf, but LIT, has an independent protective effect on miscarriage.

PSIII-1 Effect of Rearing Cross-fostered Piglets in Litters of Differing Size Relative to Sow Functional Teat Number on Pre-weaning Growth and Mortality

Litter sizes of commercial sows have increased recently, often resulting in the number of piglets exceeding the sow functional teat number. The objective of this study was to determine the effects of litter size after cross-fostering on piglet pre-weaning mortality (PWM) and growth. A RCBD was used with 13 blocks of 3 litters (total 39 litters/561 piglets); blocking factors were farrowing day, sow parity, body condition score, and functional teat number. Three Litter Size treatments (LS) relative to sow functional teat number were compared: Under (2 piglets below); Equal (same number of piglets); Over (2 piglets above). Piglets were weighed 24 h after birth and allotted to LS to create litters with similar gender ratio and average and CV of birth weight. Weaning was at 19.5 ± 0.50 d, weights and PWM were recorded. Piglet weight data were analyzed using PROC MIXED of SAS; PWM data were analyzed using PROC GLIMMIX of SAS. Models included LS and sow within block. Litter sizes averaged 12.1, 14.1, and 16.1 for the Under, Equal, and Over treatments, respectively (P ≤ 0.05). The Under treatment tended (P = 0.07) to have greater weaning weights compared to the Equal and Over treatments (Table 1). The Under treatment had lower (P ≤ 0.05) PWM than the Over treatment, with the Equal treatment being intermediate and not different to the other 2 (P > 0.05; Table 1). In conclusion, reducing litter size after cross-fostering to two piglets below the number of functional teats of the sow decreased PWM and tended to increase weaning weights.

87 Effect of Number of Source Litters Used to Create Cross-fostered Litters on Piglet Pre-weaning Mortality and Weaning Weight

Sow litter sizes have increased over recent decades, increasing the need for cross-fostering. The objective of this study was to determine the effect of the number of source litters used to create cross-fostered litters on piglet pre-weaning mortality (PWM) and weaning weight. A RCBD was used with 26 blocks of 5 litters (total 130 litters/1820 piglets), all litters consisted of 14 piglets. Blocking factors were farrowing day, sow parity, body condition score, and functional teat number, and the average and CV of piglet birth weight. Five cross-fostering treatments were compared: 0%, 1 source (all piglets remaining on the birth sow); 100%, 1 source (all piglets moved from birth to a different sow); 100%, 6+ sources (piglets from ≥ 6 birth sows used to form a litter on a different sow); 50%, 2 sources (7 piglets remaining with birth sow, 7 from one other sow); 50%, 4+ sources (7 piglets remaining with the birth sow, 7 from ≥ 3 other sows). The single-source litters were selected from those with > 14 piglets at birth, with excess piglets removed. For other treatments, piglets were selected to meet blocking factors. Piglets were weighed 24 h after birth and at weaning (19.5 ± 0.50 d); all PWM was recorded. Weight data were analyzed using PROC MIXED of SAS; PWM data were analyzed using PROC GLIMMIX of SAS. Models included Treatment and sow within block. There was no effect (P > 0.05) of treatment on weaning weights. Pre-weaning mortality was greater (P < 0.05) for the 0%, 1 source compared to the 50%, 2 source treatment, with the others being intermediate and generally not statistically different (Table 1). In conclusion, cross-fostering and/or mixing litters had no effect on weaning weights, but pre-weaning mortality was highest for the non-fostered treatment.

170 Energy values and digestibility of amino acids in dried yeast and soybean meal fed to pigs

Two experiments were conducted to evaluate the digestible energy (DE), metabolizable energy (ME), and standardized ileal digestibility (SID) of amino acids (AA) in dried yeast (DY) and soybean meal (SBM) fed to pigs. In Exp. 1, 30 barrows with an initial body weight (BW) of 20.7 ± 1.01 were assigned to 5 diets in a randomized complete block design with period and BW as blocking factors. A basal diet was prepared to contain corn, canola meal, and soybean oil as energy-contributing ingredients. Four additional diets were prepared by adding 5 or 10 g/kg DY or SBM at the expense of energy-contributing ingredients in the basal diet to estimate the DE and ME in test ingredients by regression analysis. On a dry matter basis, estimated DE and ME in DY were 4,022 and 3,352 kcal/kg, respectively, and those in SBM were 3,876 and 3,601kcal/kg, respectively. There was no difference in estimated DE or ME between DY and SBM. In Exp. 2, 21 barrows (initial BW = 20.0 ± 1.31 kg) surgically fitted with T-cannulas at the distal ileum were assigned to 3 diets in a randomized complete block design with BW as a blocking factor. Two diets were prepared to contain DY or SBM as the sole source of nitrogen, and a nitrogen-free diet was prepared to determine the basal ileal endogenous losses of AA. The SID of AA, except for Gly and Pro, in SBM were greater (P < 0.05) than in DY. The SID of indispensable AA in DY ranged from 64.7% for Thr to 86.1% for Arg, whereas those in SBM ranged from 84.8% for Thr to 92.3% for Arg. In conclusion, energy values in DY was comparable with SBM, but the SID of most AA in DY were less than in SBM.

84 Effect of rearing cross-fostered piglets in litters of either uniform or mixed birth weights on pre-weaning performance

There is limited understanding of optimum cross-fostering methods to use to maximize piglet performance. This study evaluated effects of within-litter birth weight variation after cross-fostering on pre-weaning piglet removals (PR; morbidity and mortality) and ADG. A hierarchical incomplete block design was used (blocking factors day of farrowing and sow parity and structure) with a 3x2 factorial arrangement of treatments: 1) Birth Weight Category (BWC): Light (< 1.0 kg), Medium (1.0-1.5 kg), or Heavy (1.5-2.0 kg); 2) Litter Composition (LC): Uniform (piglets of the same BWC), and Mixed (equal numbers of piglets from each BWC). Piglets were weighed 24 h after birth and allotted to form litters of 15 cross-fostered piglets. The experimental unit was 5 piglets of the same BWC (3 experimental units per litter). A total of 102 litters were allotted to 17 blocks of 6 litters (1 Uniform litter of each BWC; 3 Mixed litters) with 51 replicates (3 replicates/block of 6 litters). Weaning weights and PR were measured. PROC GLIMMIX and MIXED of SAS were used to analyze PR and other data, respectively. Models included BWC, LC, the interaction, and replicate within block. There were treatment interactions (P < 0.05) for all measures except birth weight. There was no effect (P > 0.05) of LC on weaning weight or ADG for Light or Medium piglets; Heavy piglets had greater (P < 0.05) weaning weight and ADG in Mixed than in Uniform litters. PR were greater (P < 0.05) for Light piglets in Mixed than in Uniform litters, and for Heavy piglets in Uniform than in Mixed litters. PR for Medium piglets were similar (P > 0.05) across LC treatments. In conclusion, rearing cross-fostered piglets in Uniform litters reduced PR for Light piglets, but increased PR and reduced ADG of Heavy piglets, with no effect for Medium piglets.

Haploid mouse germ cell precursors from embryonic stem cells reveal Xist activation from a single X chromosome

SummaryMammalian haploid cells have applications for genetic screening and substituting gametic genomes. Here we characterize a culture system for obtaining haploid primordial germ cell-like cells (PCGLCs) from haploid mouse embryonic stem cells (ESCs). We find that a haploid genome is maintained in PGCLCs with a high frequency indicating a substantially lower rate of diploidization than somatic cells. Characterization of the differentiating haploid ESCs reveals that Xist is activated from the single X chromosome. This observation suggests that X chromosome inactivation is initiated in haploid cells consistent with a model where autosomal blocking factors set a threshold for X-linked activators. The germline segregates from the epiblast and differs from somatic lineages in gene expression and epigenetic mechanisms. The ability of primordial germ cells for repressing Xist might contribute to the maintenance of a haploid genome.

Complexity in fitting Linear Mixed Models

Linear mixed-effects models are increasingly used for the analysis of data from experiments in fields like psychology where several subjects are each exposed to each of several different items. In addition to a response, which here will be assumed to be on a continuous scale, such as a response time, a number of experimental conditions are systematically varied during the experiment. In the language of statistical experimental design the latter variables are called experimental factors whereas factors like Subject and Item are blocking factors. That is, these are known sources of variation that usually are not of interest by themselves but still should be accounted for when looking for systematic variation in the response.