Subgroup Sizes Research Articles

Food & meal decision making in lockdown: How and who has Covid-19 affected?

The Covid-19 lockdown resulted in all but essential shops closing in many countries, with inevitable and immediate impact on food availability and choice. Reasons for specific food choices influence diet and mealtimes and can affect psychological and physical well-being. The current study aimed first to investigate whether individuals and families in the UK have changed their food choice motivations over lockdown and second to identify sub-groups in particular need of support in the event of future lockdowns. Two hundred and forty adult participants from the UK completed an online survey, consisting of a series of demographic questions, the Food Choice Questionnaire, the Family Mealtime Goals Questionnaire and some short open-ended questions. They were asked to consider their goals and motivations around food and mealtimes at two timepoints: before lockdown and Summer 2020. Results indicated that the sample placed more importance on health, weight control and mood when choosing their food after lockdown than they had before, and less importance on familiarity. A number of sub-groups were identified who may be particularly vulnerable to food-related challenges in future lockdowns including younger adults, parents and carers of children, those self-isolating and individuals who do not live within close proximity to food shops. These results are preliminary and larger sub-group sample sizes will be necessary to draw firm conclusions. Future research should consider the nature and impact of these challenges in more detail across a more varied population.

Efficacy of Tafasitamab (MOR208) Combined with Lenalidomide in Patients with High-Risk Relapsed or Refractory Diffuse Large B-Cell Lymphoma in the L-Mind Study

Introduction Patients with diffuse large B-cell lymphoma (DLBCL) that is refractory to primary immunochemotherapy are well recognized as a high-risk population with poor prognosis, and have a typical median overall survival (OS) of 6-13 months [Farooq U, et al. 2017]. Patients with 'double-hit' (MYCand eitherBCL2orBCL6) and 'triple-hit' (MYC, BCL2andBCL6) genetic aberrations are also considered to be a high-risk/poor prognosis group [Davies A. 2019]. Tafasitamab (MOR208) is an Fc-enhanced, humanized, monoclonal anti-CD19 antibody that is under investigation in combination with lenalidomide (LEN) in autologous stem cell transplant (ASCT)-ineligible patients with relapsed/refractory (R/R) DLBCL in the Phase II L-MIND study (NCT02399085) [Salles G, et al. 2020]. We report efficacy data for patients with high-risk DLBCL (primary refractory disease and double/triple-hit lymphoma [DHL/THL]) who received tafasitamab + LEN in L-MIND (data cut-off: Nov 30, 2019; median follow-up for OS, 31.8 months). Methods In the L-MIND study, patients enrolled were aged ≥18 years with R/R DLBCL (1-3 prior systemic therapies, including ≥1 CD20-targeting regimen), with an Eastern Cooperative Oncology Group performance status of 0-2 and ineligible for ASCT. Patients received 28-day cycles of tafasitamab (12 mg/kg intravenously), once weekly during Cycles 1-3 with a loading dose on Cycle 1 Day 4, then every 2 weeks during Cycles 4-12. LEN (25 mg orally) was administered on Days 1-21 of Cycles 1-12. After Cycle 12, progression-free patients received tafasitamab every 2 weeks until disease progression. The primary endpoint was objective response rate (ORR) (partial response [PR] + complete response [CR]), assessed centrally by an independent review committee. Primary refractory disease was defined as no response (CR or PR) to or progression during or within 6 months of frontline DLBCL therapy.MYC,BCL2andBCL6aberrations were determined via fluorescencein situhybridization using tumor biopsy. Results The L-MIND cohort included 15 patients with primary refractory DLBCL and two patients with DHL/THL. Patients with primary refractory DLBCL at baseline had a median age of 73 years (range 48-82; n=9 ≥70 years) and were previously exposed to a median of 2 lines of treatment (range 1-4). Of these patients, ten had stage III/IV disease, ten showed lactate dehydrogenase greater than the upper normal limit, 12 patients had germinal center B-cell DLBCL and eight exhibited intermediate-high or high-risk International Prognostic Index (IPI) status at study baseline. All 15 patients received R-CHOP or equivalent as first-line therapy; two patients previously achieved no response, whereas 13 patients had relapsed within 6 months (ten had achieved a CR and 3 a PR) after frontline therapy. Six patients had received only 1 prior therapy, whereas nine patients had ≥2 lines before L-MIND enrollment. Median time to progression after first-line therapy was 162 days (range 28-182 days); two of 15 patients had progressed within 90 days. Of the 15 patients, 13 were refractory to their last line of therapy before L-MIND. In the 15 patients with primary refractory disease, ORR was 53.3% (95% confidence interval [CI]: 26.6-78.7) and the CR rate was 33.3%, with a 30-month duration of response (DOR) rate of 50% (95% CI: 15.2-77.5) - median DOR not reached (NR). Individual response duration is shown in Figure 1 (swimmer plot): four patients who achieved CR remain in remission after >30 months. Median progression-free survival (PFS) was 5.3 months (95% CI: 0.9-NR) and PFS rate at 30 months was 33.9% (95% CI: 11.0-58.8). Median OS was 13.8 months (95% CI: 1.3-NR) and OS at 36 months was 38.1% (95% CI: 14.6-61.6). Regarding patients with DHL/THL: one with DHL achieved PR only; another patient with THL (also part of the primary refractory subgroup) achieved CR and remains in remission after >30 months. Conclusions The combination of tafasitamab + LEN showed encouraging activity, with a clinically meaningful ORR and CR rate in patients with primary refractory DLBCL, and positive responses in DHL and THL. Patients with primary refractory disease were frequently ≥70 years with stage III/IV disease and poor-risk IPI scores. Although these data should be interpreted with caution due to the small patient subgroup sizes, these clinically relevant results warrant further research with this immunotherapy in patients with difficult-to-treat DLBCL. Disclosures González-Barca: MorphoSys:Other;Janssen:Consultancy, Honoraria;Sandoz:Consultancy;Gilead:Consultancy;Roche:Honoraria;Takeda:Honoraria;Abbvie:Honoraria;Celgene:Consultancy;Kiowa:Consultancy;Celtrion:Consultancy.Duell:Morphosys:Research Funding.Sancho:Bristol-Myers Squibb:Honoraria;Celgene:Consultancy, Honoraria;Gilead:Consultancy, Honoraria;Janssen:Consultancy, Honoraria;Kern-Pharma:Consultancy, Honoraria;Novartis:Consultancy, Honoraria;Roche:Consultancy, Honoraria;Takeda:Honoraria;Celltrion:Consultancy;Sandoz:Consultancy.Nagy:MorphoSys AG:Patents & Royalties.Abrisqueta:Celgene:Consultancy, Honoraria;AbbVie:Consultancy, Honoraria, Speakers Bureau;Roche:Consultancy, Honoraria, Speakers Bureau;Janssen:Consultancy, Honoraria, Speakers Bureau.Panizo:Clínica Universidad de Navarra:Current Employment;Bristol-Myers Squibb, Kyowa Kirin:Speakers Bureau;Janssen, Roche:Membership on an entity's Board of Directors or advisory committees.Augustin:Morphosys:Research Funding;AstraZeneca:Consultancy, Research Funding;Roche:Consultancy;Novartis:Consultancy, Research Funding;Merck:Consultancy;IPSEN:Consultancy, Research Funding;Pfizer:Consultancy, Research Funding;BMS:Consultancy, Research Funding.Weirather:MorphoSys AG:Current Employment.Ambarkhane:MorphoSys AG:Current Employment.Maddocks:Seattle Genetics:Consultancy, Honoraria;Celgene:Consultancy, Honoraria;Pharmacyclics:Consultancy, Honoraria;Morphosys:Consultancy, Honoraria;ADC Therapeutics, AstraZeneca:Consultancy;BMS:Consultancy, Research Funding;Karyopharm:Consultancy.Kalakonda:Celgene:Research Funding.Salles:BMS/Celgene:Honoraria, Other: consultancy or advisory role;Takeda:Honoraria;Karyopharm:Honoraria;Genmab:Honoraria, Other;Debiopharm:Consultancy, Honoraria, Other: consultancy or advisory role;Autolos:Other: consultancy or advisory role;Abbvie:Other: consultancy or advisory role;Roche:Honoraria, Other: consultancy or advisory role;Novartis:Honoraria, Other: consultancy or advisory role;MorphoSys:Honoraria, Other: consultancy or advisory role;Janssen:Honoraria, Other: consultancy or advisory role;Epizyme:Honoraria, Other: consultancy or advisory role;Kite, a Gilead Company:Honoraria, Other: consultancy or advisory role .

Modified processes capability assessment with dynamic mean shift

AbstractRapid advancements in manufacturing technology have seen electronic products becoming lighter and thinner. This has led to production yield requirements of sawing processes in the semiconductor industry becoming increasingly strict. For sawing processes requiring a very low fraction of defective, the process capability index Cpk is widely applied for production yield measurement under the assumption of process stability. However, in practice, even when the typical control charts are implemented, dynamic and unobserved natures of the actual process mean shift may occur. Since the trial control limits are established with reference to random samples, the associated performances are also with uncertainty because of sampling error. In this paper, we investigate the effects of parameter estimation error on the development of the phase I control chart and further compare three methods with various estimators for the process standard deviation. Then, we tabulate the modified adjustment magnitudes for the dynamic Cpk under various subgroup sizes and sample sizes. On the basis of the simulation results, the proposed method can avoid overestimating the true process capability and make more trustworthy decisions. Finally, for demonstration purposes, an application of process capability measures for a sawing process is presented.

New X-bar Control Chart Using Skewness Correction Method for Skewed Distributions with Application in Healthcare

Control chart has been long-established among the highly reputable tools in statistical process control (SPC) with extensive industrial application. Shewhart chart is one of the most popular charts, but its reliability is arguable when dealing with skewed data, due to inflated false alarm rate (Type I error). In alleviating the problem, this study has developed a new X-bar control chart for monitoring of process mean using skewness correction (SC) method for skewed distributions, thus named as SC- control chart. The SC method is incorporated into the standard Shewhart’s X-bar chart, leading to the proposed univariate SC- to monitor the process mean of skewed data. It offers asymmetric control limits using the usual three sigma and the same known function of the skewness estimated from subgroups without assuming any distribution. The chart’s constants, and skewness correction factor are computed via numerical integration. To evaluate the strength and weakness of the charts, several conditions are created from different types of distributions and subgroup sizes. The SC- performance evaluation based on the false alarm rates (FAR) and probability of out-of-control (OOC) detection are accomplished using Monte Carlo simulation in SAS version 9.4. To illustrate its applicability, a real data on healthcare is employed. Its FAR performance is compared to the established charts: weighted variance X-bar R(WV- ); weighted variance X-bar S(WV- ); and standard X-bar S (ST- ). In aspect of the probability of OOC detection, the SC- is contended by the exact S chart. Extensive simulation study shows that the proposed SC- chart performs well in terms of FAR in almost all the degrees of skewness and sample sizes, n. In terms of the probability of OOC detection, it provides the closest values to those of the exact chart. It offers substantial enhancement over the established charts, and thus signifies as a preferred alternative especially in cases of skewed data.

Quality of Life in Children with Sensorineural Hearing Loss.

To assess quality of life (QOL) in pediatric patients with sensorineural hearing loss (SNHL) with the Pediatric Quality of Life Inventory 4.0 (PedsQL 4.0) and the Hearing Environments and Reflection on Quality of Life 26 (HEAR-QL-26) and HEAR-QL-28 surveys. Prospective longitudinal study. Tertiary care center. Surveys were administered to patients with SNHL (ages 2-18 years) from July 2016 to December 2018 at a multidisciplinary hearing loss clinic. Patients aged >7 years completed the HEAR-QL-26, HEAR-QL-28, and PedsQL 4.0 self-report tool, while parents completed the PedsQL 4.0 parent proxy report for children aged ≤7 years. Previously published data from children with normal hearing were used for controls. The independent t test was used for analysis. In our cohort of 100 patients, the mean age was 7.7 years (SD, 4.5): 62 participants had bilateral SNHL; 63 had mild to moderate SNHL; and 37 had severe to profound SNHL. Sixty-eight patients used a hearing device. Mean (SD) total survey scores for the PedsQL 4.0 (ages 2-7 and 8-18 years), HEAR-QL-26 (ages 7-12 years), and HEAR-QL-28 (ages 13-18 years) were 83.9 (14.0), 79.2 (11.1), 81.2 (9.8), and 77.5 (11.3), respectively. Mean QOL scores for patients with SNHL were significantly lower than those for controls on the basis of previously published normative data (P < .0001). There was no significant difference in QOL between children with unilateral and bilateral SNHL or between children with SNHL who did and did not require a hearing device. Low statistical power due to small subgroup sizes limited our analysis. It is feasible to collect QOL data from children with SNHL in a hearing loss clinic. Children with SNHL had significantly lower scores on validated QOL instruments when compared with peers with normal hearing.

Application of robust multivariate control chart with Winsorized Mean: a case study

Water pH and active ingredient concentration are two of the most important variables to consider in the manufacturing process of fungicides. If these variables do not meet the required standards, the quality of the product may be compromised and lead to poor fungicide performance when water is used as the application carrier, which is in most cases. Given the correlation between the variables, these kinds of manufacturing processes must be analyzed in multivariate settings. Thus, this paper analyzes the variables involved in the process using the multivariate control chart |S| introduced by J. A. Vargas. In the original chart, the arithmetic mean is used as the mean vector estimator. However, in this investigation the arithmetic mean was replaced by the Winsorized Mean for the purpose of evaluating the chart performance with a robust estimator. The results show that using the new estimator, the control chart is able to detect shifts in the variation of the mean vector that the traditional estimator did not. Furthermore, different subgroup sizes for the data were studied in order to examine the performance of the chart in each case. It was found that the proposed control chart is more sensible to changes when the subgroups consist of less observations, since it is able to better identify the outliers in the sample.

On the Performance of Median Based Tukey and Tukey-EWMA Charts Under Rational Subgrouping

Control chart (CC) is used to monitor the special causes that arise during the process monitoring. These special causes produce continual shifts in the process parameters that last until it is identified and removed. There is a need for such techniques, which present the true representation of the entire process. Rational subgrouping is an essential concept in Statistical Process Control (SPC) which is seldom overlooked by the practitioner. Hence, most of the manufacturing, engineering, and production processes give output products in the form of batches over smaller intervals of time. The aim of this study is to provide a median based design for Tukey and Tukey-EWMA control charts under subgrouping. It will use the idea of boxplot to monitor the process behavior. This study also provides a brief discussion regarding selecting and forming subgroups from the process data. The performance of the median based Tukey and Tukey-EWMA charts are judged using Average, Median and Standard-Deviation run-length as performance measures. We have considered subgroup sizes of m=1,5 &10 at pre-specified ARL0 equal to 370. To real-life applications of the median based tukey designs are also presented to show their implementation in food manufacturing and hard-bake processes.

Parameter Evaluation for a Statistical Mechanical Model for Binary Choice with Social Interaction

In this paper we use a statistical mechanical model as a paradigm for educational choices when the reference population is partitioned according to the socioeconomic attributes of gender and residence. We study how educational attainment is influenced by socioeconomic attributes of gender and residence for five selected developing countries. The model has a social and a private incentive part with coefficients measuring the influence individuals have on each other and the external influence on individuals, respectively. The methods of partial least squares and the ordinary least squares are, respectively, used to estimate the parameters of the interacting and the noninteracting models. This work differs from the previous work that motivated this work in the following sense: (a) the reference population is divided into subgroups with unequal subgroup sizes, (b) the proportion of individuals in each of the subgroups may depend on the population size N, and (c) the method of partial least squares is used for estimating the parameters of the model with social interaction as opposed to the least squares method used in the earlier work.

A distribution-free Phase I monitoring scheme for subgroup location and scale based on the multi-sample Lepage statistic

In this paper, we introduce an exactly distribution-free procedure for Phase I analysis which is capable of assessing stability of both location and scale parameters of the process using a single plotting statistic. A large proportion of literature on Phase I or retrospective analysis assumes normality. The normality assumption is often invalid in practice. In recent years, researchers have proposed some distribution-free (nonparametric) Phase I schemes. Most of these schemes facilitate assessing either the location or the scale, individually but not both simultaneously. Practitioners often consider a two-chart scheme, one for monitoring the location parameter and the other the scale parameter in tandem. Nevertheless, such two-chart schemes have certain practical disadvantages. There is a plethora of literature on distribution-free Phase II schemes for simultaneously monitoring the location and scale parameters of a process distribution using a single statistic. To the best of our knowledge, there is no literature on Phase I or retrospective analysis of both location and scale adopting a single statistic. To fill this research gap, we propose a distribution-free Phase I monitoring scheme for both location and scale parameters based on the multi-sample Lepage statistic. The proposed Phase I scheme can be implemented even if subgroup sizes are unequal. Unlike, most of the existing schemes, it does not require the restriction of equal sizes for each subgroup. The design and implementation of the proposed scheme is simple. We clearly outline and illustrate the implementation steps with an example. Compared to several existing two-chart schemes, the proposed one-chart scheme has performance advantages in a variety of cases, especially for skewed and heavy-tailed data. We also study certain interesting features of the proposed scheme.

Does an impaired capacity for self-care impact the prevalence of social and emotional loneliness among elderly people?

Purpose The purpose of this paper is to explore the impact of self-care on the prevalence of loneliness among elderly people living in retirement homes and older people living in their homes/communities. Design/methodology/approach The research was conducted through standardized SELSA-L assessment loneliness questionnaires and the Self Care Assessment Worksheet for self-care assessment. The results were processed using the Kruskal–Wallis test. Findings The obtained results have shown that impaired self-care ability affects the prevalence of loneliness among the elderly almost the same in both groups of participants. However, regarding the relationship between the state of health and self-care, only a statistically significant difference in the prevalence of loneliness is found in the case of the participants living in their homes, with the worst health condition affecting the poorer psychological care. Research limitations/implications It is necessary to point out the limitations of the research, primarily sample limitations and the selected design of the study. The sample consisted of two different and relatively small groups of participants which could adversely affect the representativeness of the sample and reduce the possibility of generalising the results. The next limiting factor is the age distribution the authors used in the research, where the age of the participants as a very important variable was collected by age range and not precisely which consequently resulted in inequality in subgroup sizes. Thus, the middle age (75–85) covers up to ten years, which is a huge range at an older age and can mean major differences in functional ability, and can impact the self-care assessment. Practical implications Nurses are indispensable in care for the elderly and they need to promote and encourage self-care of the elderly through health care. Elderly people living in retirement homes should be allowed to participate equally in health care in order to preserve their own autonomy and dignity. However, to benefit those who live in their homes, nurses should be connected to the local community and thus stimulate various forms of preventative (testing blood sugar levels, blood pressure and educating on the importance of preventive examinations) or recreational activities in the environment of elderly people with the goal of preserving their functional abilities. Originality/value The impact of self-care on loneliness was not sufficiently researched, and this paper contributed to understanding the complexity of loneliness phenomena among the elderly with the aim of developing a model of prevention.

Impact of social capital, harassment of women and girls, and water and sanitation access on premature birth and low infant birth weight in India.

BackgroundGlobally, preterm birth (PTB) and low infant birth weight (LBW) are leading causes of maternal and child morbidity and mortality. Inadequate water and sanitation access (WASH) are risk factors for PTB and LBW in low-income countries. Physical stress from carrying water and psychosocial stress from addressing sanitation needs in the open may be mechanisms underlying these associations. If so, then living in a community with strong social capital should be able to buffer the adverse effects of WASH on birth outcomes. The objective of this study is to assess the relationships between WASH access and social conditions (including harassment and social capital) on PTB and LBW outcomes among Indian women, and to test whether social conditions modified the association between WASH and birth outcomes.Methods and findingsThis cohort study examined the effect of pre-birth WASH and social conditions on self-reported PTB status and LBW status for 7,926 women who gave birth between 2004/2005 and 2011/2012 Waves of the India Human Development Survey. PTB and LBW occurred in 14.9% and 15.5% of women, respectively. After adjusting for maternal biological and socioeconomic conditions, PTB was associated with sharing a building/compound latrine (Odds Ratio (OR) = 1.55; 95% Confidence Interval (CI) = 1.01, 2.38) versus private latrine access, but suggested an effect in the opposite direction for sharing a community/public latrine (OR = 0.67; CI = 0.45, 1.01). Open defecation, type of drinking water source, minutes per day spent fetching water, and one-way time to a drinking water source were not associated with PTB. LBW was associated with spending more than two hours per day fetching water compared to less than two hours (OR = 1.33; CI = 1.05, 1.70) and suggested an association with open defecation (OR = 1.22; CI = 1.00, 1.48), but was not associated with other types of sanitation, type of drinking water source, or time to a drinking water source. Harassment of women and girls in the community was associated with both PTB (OR = 1.33; CI = 1.09, 1.62) and LBW (OR = 1.26; CI = 1.03, 1.54). The data also showed a possible association of local crime with LBW (OR = 1.30; CI = 1.00, 1.68). Statistically significant (p<0.05) evidence of effect modification was only found for collective efficacy on the association between type of sanitation access and PTB. In addition, stratified analyses identified differences in effect size for walking time to the primary drinking water source and PTB by crime, sanitation access and PTB by harassment, and total hours per day fetching water and LBW by collective efficacy. Limitations of this observational study include risk of bias, inability to confirm causality, reliance on self-reported outcomes, and limited sub-group sample sizes for testing effect modification.ConclusionsThe relationship between adverse birth outcomes and sanitation access, domestic water fetching, crime, and gender-based harassment suggests physical and psychosocial stress are possible mechanisms by which WASH access affects PTB and LBW among Indian women. Interventions that reduce domestic responsibilities related to water and sanitation and change social norms related to gender-based harassment may reduce rates of PTB and LBW in India.

Development of predictive signatures for treatment selection in precision medicine with survival outcomes.

For survival endpoints in subgroup selection, a score conversion model is often used to convert the set of biomarkers for each patient into a univariate score and using the median of the univariate scores to divide the patients into biomarker-positive and biomarker-negative subgroups. However, this may lead to bias in patient subgroup identification regarding the 2 issues: (1) treatment is equally effective for all patients and/or there is no subgroup difference; (2) the median value of the univariate scores as a cutoff may be inappropriate if the sizes of the 2 subgroups are differ substantially. We utilize a univariate composite score method to convert the set of patient's candidate biomarkers to a univariate response score. We propose applying the likelihood ratio test (LRT) to assess homogeneity of the sampled patients to address the first issue. In the context of identification of the subgroup of responders in adaptive design to demonstrate improvement of treatment efficacy (adaptive power), we suggest that subgroup selection is carried out if the LRT is significant. For the second issue, we utilize a likelihood-based change-point algorithm to find an optimal cutoff. Our simulation study shows that type I error generally is controlled, while the overall adaptive power to detect treatment effects sacrifices approximately 4.5% for the simulation designs considered by performing the LRT; furthermore, the change-point algorithm outperforms the median cutoff considerably when the subgroup sizes differ substantially.

A variational EM method for mixed membership models with multivariate rank data: An analysis of public policy preferences

In this article, we consider modeling ranked responses from a heterogeneous population. Specifically, we analyze data from the Eurobarometer 34.1 survey regarding public policy preferences toward drugs, alcohol, and AIDS. Such policy preferences are likely to exhibit substantial differences within as well as across European nations reflecting a wide variety of cultures, political affiliations, ideological perspectives, and common practices. We use a mixed membership model to account for multiple subgroups with differing preferences and to allow each individual to possess partial membership in more than one subgroup. Previous methods for fitting mixed membership models to rank data in a univariate setting have utilized an MCMC approach and do not estimate the relative frequency of each subgroup. We propose a variational EM approach for fitting mixed membership models with multivariate rank data. Our method allows for fast approximate inference and explicitly estimates the subgroup sizes. Analyzing the Eurobarometer 34.1 data, we find interpretable subgroups which generally agree with the “left versus right” classification of political ideologies.

Failure to achieve early disease response is associated with inferior survival in patients with newly diagnosed multiple myeloma

Failure to achieve early disease response is associated with inferior survival in patients with newly diagnosed multiple myeloma

Female Spider Monkeys (Ateles geoffroyi) Cope with Anthropogenic Disturbance Through Fission-Fusion Dynamics.

Most primates live in habitats with some level of anthropogenic disturbance, and such disturbances have a larger impact on frugivorous primates that are more sensitive to ecological disruptions than folivores. Fecal glucocorticoid metabolites provide insight into how the external environment affects internal physiological state, and thus provide information on how anthropogenic pressures become embodied. Here, I examine how subgroup size and glucocorticoids vary with high and low fruit abundance, and how fruit abundance, subgroup size, and activity budget affect fecal glucocorticoid metabolites in female spider monkeys (Ateles geoffroyi) living in an anthropogenically disturbed habitat. I measured these variables via behavioral, ecological, and fecal sampling for 15 months in 17 female spider monkeys at El Zota Biological Field Station. Subgroup size was significantly larger during periods of high fruit abundance, but glucocorticoids did not differ between periods of low and high fruit abundance. Monthly fruit abundance predicted subgroup sizes significantly, but did not predict fecal glucocorticoid concentrations. Increased resting time and reproductive state predicted fecal glucocorticoid concentrations significantly, but travel and foraging time had no significant effect on glucocorticoid concentrations. Individual resting time over the study period correlated negatively with glucocorticoid concentrations. These results suggest that spider monkeys cope with variation in fruit abundance by adjusting subgroup size, and that these adjustments may mitigate environmental stress in this mildly seasonal environment. The large, relatively productive forest size at this site, and the availability of anthropogenic food sources, enable this population of spider monkeys to cope with human-induced habitat disturbance.

Spatial Consensus Queries in a Collaborative Environment

We introduce a new type of query for a location-based social network platform. Consider a scenario in which a group of users is trying to find a common meeting location, yet attempting to include all group members is introducing a significant traveling cost to most of them. In this article, we formulate a new query type called the consensus query , which can be used to help users explore these trade-off options to find a solution upon which everyone can agree. Specifically, we study the problem of evaluating consensus queries in the context of nearest neighbor queries, where the group is interested in finding a meeting place that minimizes the travel distance for at least a specified number of group members. To help the group in selecting a suitable solution, the major challenge is to find optimal subgroups of all allowable subgroup sizes, i.e., greater or equal to the minimum specified subgroup size, that minimize the travel distances. We develop incremental algorithms to evaluate in one pass the optimal query subgroups of different sizes along with their corresponding nearest data points. These subsets, which are evaluated by the location-based service provider, constitute the answer set that is returned to the group. The group then collaboratively selects the final answer from the candidate answer set. An extensive experimental study shows the efficiency and effectiveness of our proposed techniques.

Watch out or relax: conspecifics affect vigilance in wild spider monkeys (Ateles geoffroyi)

In most animal species, predation risk is considered the main factor affecting vigilance, and an individual is expected to spend less time vigilant in larger than in smaller groups. However, vigilance patterns in primates appear to differ, with no consistency in group-size effects. As individuals in highly gregarious species such as diurnal primates face frequent threats from group members, there may be increased vigilance in larger groups to monitor conspecifics rather than or in addition to predators. We tested this hypothesis in wild spider monkeys, which live in communities but fission and fuse in subgroups of variable size and membership throughout the same day. We found no overall effect of subgroup size, as traditionally measured, on vigilance. However, a possible explanation is that vigilance may be effectively shared only with individuals in close proximity, rather than with all subgroup members. We found that a larger number of neighbours (i.e., subgroup members within 5 m) was associated with a lower proportion of time individuals spent vigilant, which is similar to findings in other studies. Another social factor that may affect individuals’ vigilance is the possibility of between-community encounters. Higher levels of vigilance can be expected in areas closer to the boundary of the home range, where between-community encounters are more likely to occur compared with non-boundary areas. We found that location in terms of boundary vs. non-boundary areas had a significant effect on the time individuals spent vigilant in the expected direction. We also found that location modulated the effect of subgroup size on vigilance: only in the boundary areas did larger subgroup sizes result in less individual vigilance time. We concluded that conspecifics affect vigilance of wild spider monkeys in multiple ways.

Stem cell therapy for heart disease: truly beneficial?

Stem cell therapy for heart disease: truly beneficial?

An exploration of quality management practices, perceptions and program maturity in the supply chain

Purpose – The purpose of this paper is to examine differences among industry classes and supply chain positions in order to gain insight into quality management program maturity across industries and within supply chains. Design/methodology/approach – Data for comparison in this study comes from an e-mail survey of professionals across the USA, employed primarily in sourcing or logistics (i.e. Institute for Supply Management (ISM) and Council for Supply Chain Management Professionals (CSCMP)). Findings – This study found that quality maturity varies by industry class. While prior studies have found differences by industry class, they have been limited to at most three classes, while this study examined 17 classes. This study also examines quality maturity by supply chain position, with the finding that quality maturity differed by supply chain position depending on how position is defined. Questions are raised regarding the proper characterization of supply chain position. Research limitations/implications – The sample group represents members in only two professional groups, ISM and CSCMP. Not all industry groups or supply chain positions were well-represented due to some small sub-group sizes. Practical implications – Quality program maturity is generally not uniform and there are potentially many opportunities for substantial improvement across various sectors by specific industry. Partnering with suppliers is a recommended approach for sectors lagging in quality maturity. Originality/value – This research extends the examination of quality management practice in the supply chain by studying a large number of industry classes and supply chain positions and assesses differences in quality maturity across these classes and positions.

More than one million new American Indians in 2000: who are they?

More than one million people reported their race as American Indian/Alaska Native (AIAN) in the 2000 U.S. census but did not do so in the 1990 census. We ask three questions. First, which subgroups had the greatest numerical growth? Second, which subgroups had the greatest proportional increase? And third, are the 2000 single-race AIANs and the 1990 AIANs the same set of people? We use full-count and high-density decennial census data; adjust for birth, death, and immigration; decompose on age, gender, Latino origin, education, and birth state; and compare the observed subgroup sizes in 2000 with the sizes expected based on 1990 counts. The largest numerical increases were among adolescent and middle-aged non-Latinos, non-Latino women, and adults with no college degree. Latinos, women, highly educated adults, and people born in Eastern states had the largest proportionate gains. The ability to report multiple races in 2000 and the new federal definition of "American Indian" may have especially affected these groups, although personal-identity changes are probably also involved. We find that thousands of new Latino AIANs reported only one race in 2000, but many 1990 AIANs reported multiple races in 2000. Thus, the 1990 AIANs and 2000 single-race AIANs are not always the same individuals.