5,240 research outputs found
Risk-Averse Stochastic Integer Programs for Mixed-Model Assembly Line Sequencing Problems
A variety of optimization formulations have been proposed for mixed-model assembly sequencing problems with stochastic demand and task times. In the real world, however, mixed-model assembly lines are faced with more challenging uncertainties including timely part delivery, material quality, upstream sub-assembly completion and availability of other resources. In addition, sub-assembly lines must meet deadlines imposed by downstream stations. The inevitable disruptions require resequencing. We present a risk-averse stochastic mixed-integer model for mixed-model assembly line resequencing problems to increase on-time performance
Recommended from our members
Trends in the utilisation of emergency departments in California, 2005-2015: a retrospective analysis.
ObjectiveTo examine current trends in the characteristics of patients visiting California emergency departments (EDs) in order to better direct the allocation of acute care resources.DesignA retrospective study.SettingWe analysed ED utilisation trends between 2005 and 2015 in California using non-public patient data from California's Office of Statewide Health Planning and Development.ParticipantsWe included all ED visits in California from 2005 to 2015.Primary and secondary outcome measuresWe analysed ED visits and visit rates by age, sex, race/ethnicity, payer and urban/rural trends. We further examined age, sex, race/ethnicity and urban/rural trends within each payer group for a more granular picture of the patient population. Additionally, we looked at the proportion of patients admitted from the ED and distribution of diagnoses.ResultsBetween 2005 and 2015, the annual number of ED visits increased from 10.2 to 14.2 million in California. ED visit rates increased by 27.8% (p<0.001), with the greatest increases among patients aged 5-19 (37.4%, p<0.001) and 45-64 years (41.1%, p<0.001), non-Hispanic Black and Hispanic patients (56.8% and 48.8%, p<0.001), the uninsured and Medicaid-insured (36.1%, p=0.002; 28.6%, p<0.001) and urban residents (28.3%, p<0.001). The proportion of ED visits resulting in hospitalisation decreased by 18.3%, with decreases across all payer groups.ConclusionsOur findings reveal an increasing demand for emergency care and may reflect current limitations in accessing care in other parts of the healthcare system. Policymakers may need to recognise the increasingly vital role that EDs are playing in the provision of care and consider ways to incorporate this changing reality into the delivery of health services
Media consumption and creation in attitudes toward and knowledge of inflammatory bowel disease: web-based survey
BACKGROUND: Inflammatory bowel disease (IBD) is a chronic gastrointestinal condition affecting over 5 million people globally and 1.6 million in the United States but currently lacks a precisely determined cause or cure. The range of symptoms IBD patients experience are often debilitating, and the societal stigmas associated with some such symptoms can further degrade their quality of life. Better understanding the nature of this public reproach then is a critical component for improving awareness campaigns and, ultimately, the experiences of IBD patients. OBJECTIVE: The objective of this study was to explore and assess the public's awareness and knowledge of IBD, as well as what relationship, if any, exists between the social stigma surrounding IBD, knowledge of the disease, and various media usage, including social media. METHODS: Utilizing a Web-based opt-in platform, we surveyed a nationally representative sample (n=1200) with demographics mirroring those of the US Census figures across baseline parameters. Using constructed indices based on factor analysis, we were able to build reliable measures of personal characteristics, media behaviors, and perceptions and knowledge of IBD. RESULTS: Among the American public, IBD is the most stigmatized of seven diseases, including genital herpes and human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). Additionally, IBD knowledge is generally low with 11.08% (133/1200) of the sample indicating no familiarity with the disease and 85.50% (1026/1200) of participants inaccurately answering two-thirds of the IBD index questions with which their knowledge was assessed. Increased knowledge of IBD is associated with lower levels of stigma. However, social media use is currently related to lower levels of IBD knowledge (P<.05). Furthermore, findings indicate that participants who most frequently engaged in producing social media content are less knowledgeable about IBD (P<.10), highlighting the potential for a dangerous cycle should they be contributing to a Web-based IBD dialogue. CONCLUSIONS: Greater efforts must be taken to stymie IBD misinformation across all media, but especially in social media channels, to increase IBD knowledge and reduce stigma surrounding IBD. These findings pave the way for further research qualitatively examining the pervasiveness of specific IBD messages found in today's social media landscape and their impact on enacted stigmas so as to better equip providers and patient advocacy organizations with impactful communication solutions
Heterologous screening of hybridomas for the development of broad-specific monoclonal antibodies against deoxynivalenol and its analogues
Hapten heterology was introduced into the steps of hybridoma selection for the development of monoclonal antibodies (MAbs) against deoxynivalenol (DON). Firstly, a novel heterologous DON hapten was synthesised and covalently coupled to proteins (i.e. bovine serum albumin (BSA), ovalbumin and horseradish peroxidase) using the linkage of cyanuric chloride (CC). After immunisation, antisera from different DON immunogens were checked for the presence of useful antibodies. Next, both homologous and heterologous enzyme-linked immunosorbent assays were conducted to screen for hybridomas. It was found that heterologous screening could significantly reduce the proportion of false positives and appeared to be an efficient approach for selecting hybridomas of interest. This strategy resulted in two kinds of broad-selective MAbs against DON and its analogues. They were quite distinct from other reported DON-antibodies in their cross-reactivity profiles. A unique MAb 13H1 derived from DON-CC-BSA immunogen could recognise DON and its analogues in the order of HT-2 toxin > 15-acetyl-DON > DON > nivalenol, with IC50 ranging from 1.14 to 7.69 mu g/ml. Another preferable MAb 10H10 generated from DON-BSA immunogen manifested relatively similar affinity to DON, 3-acetyl-DON and 15-acetyl-DON, with IC50 values of 22, 15 and 34 ng/ml, respectively. This is the first broad-specific MAb against DON and its two acetylated forms and thus it can be used for simultaneous detection of the three mycotoxins
Comparison of enzyme-linked immunosorbent assay, surface plasmon resonance and biolayer interferometry for screening of deoxynivalenol in wheat and wheat dust
A sample preparation method was developed for the screening of deoxynivalenol (DON) in wheat and wheat dust. Extraction was carried out with water and was successful due to the polar character of DON. For detection, an enzyme-linked immunosorbent assay (ELISA) was compared to the sensor-based techniques of surface plasmon resonance (SPR) and biolayer interferometry (BLI) in terms of sensitivity, affinity and matrix effect. The matrix effects from wheat and wheat dust using SPR were too high to further use this screenings method. The preferred ELISA and BLI methods were validated according to the criteria established in Commission Regulation 519/2014/EC and Commission Decision 2002/657/EC. A small survey was executed on 16 wheat lots and their corresponding dust samples using the validated ELISA method. A linear correlation (r = 0.889) was found for the DON concentration in dust versus the DON concentration in wheat (LOD wheat: 233 g/kg, LOD wheat dust: 458 g/kg)
Dog owners show experience-based viewing behaviour in judging dog face approachability
Our prior visual experience plays a critical role in face perception. We show superior perceptual performance for differentiating conspecific (vs non-conspecific), own-race (vs other-race) and familiar (vs unfamiliar) faces. However, it remains unclear whether our experience with faces of other species would influence our gaze allocation for extracting salient facial information. In this eye-tracking study, we asked both dog owners and non-owners to judge the approachability of human, monkey and dog faces, and systematically compared their behavioural performance and gaze pattern associated with the task. Compared to non-owners, dog owners assessed dog faces with shorter time and fewer fixations, but gave higher approachability ratings. The gaze allocation within local facial features was also modulated by the ownership. The averaged proportion of the fixations and viewing time directed at the dog mouth region were significantly less for the dog owners, and more experienced dog owners tended to look more at the dog eyes, suggesting the adoption of a prior experience-based viewing behaviour for assessing dog approachability. No differences in behavioural performance and gaze pattern were observed between dog owners and non-owners when judging human and monkey faces, implying that the dog owner’s experience-based gaze strategy for viewing dog faces was not transferable across faces of other species
Neuroblastoma patient outcomes, tumor differentiation, and ERK activation are correlated with expression levels of the ubiquitin ligase UBE4B.
BackgroundUBE4B is an E3/E4 ubiquitin ligase whose gene is located in chromosome 1p36.22. We analyzed the associations of UBE4B gene and protein expression with neuroblastoma patient outcomes and with tumor prognostic features and histology.MethodsWe evaluated the association of UBE4B gene expression with neuroblastoma patient outcomes using the R2 Platform. We screened neuroblastoma tumor samples for UBE4B protein expression using immunohistochemistry. FISH for UBE4B and 1p36 deletion was performed on tumor samples. We then evaluated UBE4B expression for associations with prognostic factors and with levels of phosphorylated ERK in neuroblastoma tumors and cell lines.ResultsLow UBE4B gene expression is associated with poor outcomes in patients with neuroblastoma and with worse outcomes in all patient subgroups. UBE4B protein expression was associated with neuroblastoma tumor differentiation, and decreased UBE4B protein levels were associated with high-risk features. UBE4B protein levels were also associated with levels of phosphorylated ERK.ConclusionsWe have demonstrated associations between UBE4B gene expression and neuroblastoma patient outcomes and prognostic features. Reduced UBE4B protein expression in neuroblastoma tumors was associated with high-risk features, a lack of differentiation, and with ERK activation. These results suggest UBE4B may contribute to the poor prognosis of neuroblastoma tumors with 1p36 deletions and that UBE4B expression may mediate neuroblastoma differentiation
The ectodomain of Toll-like receptor 9 is cleaved to generate a functional receptor.
Mammalian Toll-like receptors (TLRs) 3, 7, 8 and 9 initiate immune responses to infection by recognizing microbial nucleic acids; however, these responses come at the cost of potential autoimmunity owing to inappropriate recognition of self nucleic acids. The localization of TLR9 and TLR7 to intracellular compartments seems to have a role in facilitating responses to viral nucleic acids while maintaining tolerance to self nucleic acids, yet the cell biology regulating the transport and localization of these receptors remains poorly understood. Here we define the route by which TLR9 and TLR7 exit the endoplasmic reticulum and travel to endolysosomes in mouse macrophages and dendritic cells. The ectodomains of TLR9 and TLR7 are cleaved in the endolysosome, such that no full-length protein is detectable in the compartment where ligand is recognized. Notably, although both the full-length and cleaved forms of TLR9 are capable of binding ligand, only the processed form recruits MyD88 on activation, indicating that this truncated receptor, rather than the full-length form, is functional. Furthermore, conditions that prevent receptor proteolysis, including forced TLR9 surface localization, render the receptor non-functional. We propose that ectodomain cleavage represents a strategy to restrict receptor activation to endolysosomal compartments and prevent TLRs from responding to self nucleic acids
A narrative review of the role of foods as dietary sources of vitamin D of ethnic minority populations with darker skin: the underestimated challenge
In recent years, vitamin D deficiency has attracted attention worldwide. Especially many
ethnic minority populations are considered at high-risk of vitamin D deficiency, owing to a lesser
ability to synthesis vitamin D from sunlight (ultraviolet B), due to the skin pigment melanin and/or
reduced skin exposure due to coverage required by religious and cultural restrictions. Therefore,
vitamin D intake from dietary sources has become increasingly important for many ethnic minority
populations to achieve adequate vitamin D status compared with the majority of the population.
The aim of the study was critically evaluate the vitamin D intake and vitamin D status of the
ethnic minority populations with darker skin, and also vitamin D absorption from supplements
and ultraviolet B. Pubmed, Embaase and Scopus were searched for articles published up to October
2018. The available evidence showed ethnic minority populations generally have a lower vitamin
D status than the majority populations. The main contributory food sources for dietary vitamin D
intake were different for ethnic minority populations and majority populations, due to vary dietary
patterns. Future strategies to increase dietary vitamin D intake by food fortification or biofortification
needs to be explored, not only for the majority population but more specifically for ethnic minority
populations who are generally of lower vitamin D status
- …