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Psychrotolerant sporeformers pose a challenge to maintaining fluid milk quality. Dynamic temperature changes along the supply chain can favor the germination and growth of these bacteria and lead to fluid milk spoilage. In this study, we aim to expand on our previous work on predicting milk spoilage due to psychrotolerant sporeformers. The key model innovations include (1) the ability to account for changing temperatures along the supply chain, and (2) a deployed user-friendly interface to allow easy access to the model. Using the frequencies and concentrations of 8 Bacillales subtypes specific to fluid milk collected in New York, the model simulated sporeformer growth in half-gallons of high-temperature, short-time (HTST) pasteurized fluid milk transported from processing facility to retail store and then to consumer. The Monte Carlo simulations predicted that 44.3% of half-gallons of milk were spoiled (defined as having a bacterial concentration >20,000 cfu/mL, a conservative estimate that represents the Pasteurized Milk Ordinance regulatory limit) after 21 d of refrigerated storage at consumer's home. Model validations showed that the model was the most accurate in predicting the mean sporeformer concentration at low temperatures (i.e., at 3°C and 4°C; compared with higher temperatures at 6°C and 10°C) within the first 21 d of consumer storage, with a root mean square error of 0.29 and 0.34 log 10 cfu/mL, respectively. Global sensitivity analyses indicated that home storage temperature, facility-to-retail transportation temperature, and initial spore concentration were the 3 most influential factors for predicting milk spoilage on d 21 of shelf life. What-if scenarios indicated that microfiltration was predicted to be the most effective strategy to reduce spoilage. The implementation of this strategy (assumed to reduce initial spore concentration by 2.2 log 10 cfu/mL) was predicted to reduce the percentage of spoiled milk by 17.0 percentage points on d 21 of storage and could delay the date by which 50% of half-gallons of milk were spoiled, from d 25 to 35. Overall, the model is readily deployed as a digital tool for assessing fluid milk spoilage along the supply chain and evaluating the effectiveness of intervention strategies, including those that target storage temperatures at different supply chain stages. [ABSTRACT FROM AUTHOR]

Late blowing defect (LBD) is an important spoilage issue in semi-hard cheese, with the outgrowth of Clostridium tyrobutyricum spores during cheese aging considered to be the primary cause. Although previous studies have explored the microbial and physicochemical factors influencing the defect, a risk assessment tool that allows for improved and rational management of LBD is lacking. The purpose of this study was to develop a predictive model to estimate the probability of LBD in Gouda cheese and evaluate different intervention strategies. The spore concentration distribution of butyric acid bacteria (BAB) in bulk tank milk was obtained from 8 dairy farms over 12 mo. The concentration of C. tyrobutyricum from raw milk to the end of aging was simulated based on Gouda brined for 2 d in saturated brine at 8°C and aged at 13°C. Predicted C. tyrobutyricum concentrations during aging and estimated concentration thresholds in cheese at onset of LBD were used to predict product loss due to LBD during a simulated 1-yr production. With the estimated concentration thresholds in cheese ranging from 4.36 to 4.46 log most probable number (MPN)/kg of cheese, the model predicted that 9.2% (±1.7%) of Gouda cheese showed LBD by d 60; cheeses predicted to show LBD at d 60 showed a mean pH of 5.39 and were produced with raw milk with a mean BAB spore count of 143 MPN/L. By d 90, 36.1% (±3.4%) of cheeses were predicted to show LBD, indicating that LBD typically manifests between d 60 and 90, which is consistent with observations from the literature and the cheese industry. Sensitivity analysis indicated that C. tyrobutyricum maximum growth rate as well as concentration threshold in cheese at onset of LBD are the most important variables, identifying key data needs for development of more accurate models. The implementation of microfiltration or bactofugation of raw milk (assumed to show 98% efficiency of spore removal) in our model prevented occurrence of LBD during the first 60 d of aging. Overall, our findings provide a framework for predicting the occurrence of LBD in Gouda as well as other cheeses and illustrate the value of developing digital tools for managing dairy product quality. [ABSTRACT FROM AUTHOR]

[Display omitted] • Participants relied mostly on the eye-region for detecting surprised expressions. • Classification images from 'surprise' responses enhanced the eye-region. • Classification images from 'not surprise' responses resembled disgust. • Removal of eyebrows localized sampling to the eyes. • Face images with added classification images convey 'surprise' emotional valence. The classification image (CI) technique has been used to derive templates for judgements of facial emotion and reveal which facial features inform specific emotional judgements. For example, this method has been used to show that detecting an up- or down-turned mouth is a primary strategy for discriminating happy versus sad expressions. We explored the detection of surprise using CIs, expecting widened eyes, raised eyebrows, and open mouths to be dominant features. We briefly presented a photograph of a female face with a neutral expression embedded in random visual noise, which modulated the appearance of the face on a trial-by-trial basis. In separate sessions, we showed this face with or without eyebrows to test the importance of the raised eyebrow element of surprise. Noise samples were aggregated into CIs based on participant responses. Results show that the eye-region was most informative for detecting surprise. Unless attention was specifically directed to the mouth, we found no effects in the mouth region. The eye effect was stronger when the eyebrows were absent, but the eyebrow region was not itself informative and people did not infer eyebrows when they were missing. A follow-up study was conducted in which participants rated the emotional valence of the neutral images combined with their associated CIs. This verified that CIs for 'surprise' convey surprised expressions, while also showing that CIs for 'not surprise' convey disgust. We conclude that the eye-region is important for the detection of surprise. [ABSTRACT FROM AUTHOR]

Light Emitting Diode (LED) luminaires and lamps are energy-saving and environmental friendly alternatives to traditional lighting products. However, current luminous flux depreciation test at luminaire and lamp level requires a minimum of 6000 h testing, which is even longer than the product development cycle time. This paper develops an accelerated test method for luminous flux depreciation to reduce the test time within 2000 h at an elevated temperature. The method is based on lumen maintenance boundary curve, obtained from a collection of LED source lumen depreciation data, known as LM-80 data. The exponential decay model and Arrhenius acceleration relationship are used to determine the new threshold of lumen maintenance and acceleration factor. The proposed method has been verified by a number of simulation studies and experimental data for a wide range of LED luminaire and lamp types from both internal and external experiments. The qualification results obtained by the accelerated test method agree well with traditional 6000 h tests. [ABSTRACT FROM AUTHOR]

Consider the following nonlinear difference equation of order k + 1 with a forcing term (0.1) x n + 1 − a n x n + b n f ( x n − k ) = r n , n = 0 , 1 , … where { a n } is a positive sequence in (0, 1], { b n } is a positive sequence, { r n } is a real sequence, k is a nonnegative integer, and f : ( τ , ∞) → ( τ , ∞) is a continuous function with −∞ ≤ τ ≤ 0. We establish a sufficient condition for every solution of Eq. (0.1) to converge to zero as n → ∞. Several new global attractivity results are obtained for some special cases of Eq. (0.1) which have been studied widely in the literature. Our results can be applied to some difference equations derived from mathematical biology. [ABSTRACT FROM AUTHOR]

Highlights: [•] β-Carotene was encapsulated in nanoemulsions and emulsions. [•] Initial droplet size influenced potential biological fate of delivery systems. [•] Lipid digestion rate and extent increased with decreasing droplet size. [•] β-Carotene bioaccessibility increased with decreasing droplet size. [ABSTRACT FROM AUTHOR]

Abstract: Diets rich in carotenoids have been correlated with a reduced risk of developing certain types of chronic diseases, but these bioactive components have low intestinal absorption due to their hydrophobic nature. The aim of this work was to study the effect of carrier oil composition (medium-chain triglyceride (MCT) to long-chain triglyceride (LCT) ratio) and total carrier oil concentration (1% or 4% w/w) on the physical stability, lipid digestibility and bioaccessibility of β-carotene-loaded nanoemulsions, using a simulated digestion process. Lipolysis led to an appreciable increase in the size and negative charge on the particles in the system. The total fraction of triacylglycerols converted to free fatty acids decreased as the percentage of LCT within the lipid phase increased, particularly for the nanoemulsions with higher fat contents. There was an increase in β-carotene bioaccessibility as the LCT within the lipid phase increased for low fat nanoemulsions, which was attributed to the increased solubilisation capacity of mixed micelles formed by LCT. β-carotene bioaccessibility showed a complex relationship on LCT content for high fat nanoemulsions, due to the opposing effects of lipid digestion and micelle solubilisation. These results may facilitate the optimisation of delivery systems for lipophilic bioactive compounds for food or pharmaceutical applications. [Copyright &y& Elsevier]

Abstract: The fatigue behaviour of small scale composite unit cells consisting of seven fibres and surrounding matrix is developed for use in fatigue simulations. The predicted fatigue properties of these 7-fibre unit cells are compared with the fatigue properties of single glass fibres and of unidirectional composite dog–bone specimens. These predicted results provide stochastic fatigue characteristics that can be used as input for modelling the fatigue behaviour of larger composite structures. [Copyright &y& Elsevier]

Abstract: A multi-scale numerical fatigue modelling methodology is proposed for the characterization of axial tension–tension fatigue behaviour of unidirectional Glass Fibre Reinforced Polymer (GFRP) composites. The methodology is developed to link the dominant fibre failure mechanism to composite fatigue properties, by a three-step geometrical up-scaling process. This study aims to provide composite fatigue predictions by only using the material properties of fibres and matrix. Compared to the experimental results, the fatigue model over-predicts fatigue lives and gives reasonable estimations of axial stiffness degradation curves of the unidirectional GFRP composite dog-bone specimens. [Copyright &y& Elsevier]

Abstract: There are at least five cancers with uniquely high incidence amongst East and Southeast Asian ethnic groups – namely nasopharyngeal carcinoma (NPC); gastric carcinoma; hepatocellular carcinoma (HCC); adeno-carcinoma of the lung in female non-smokers and nasal NK/T-cell lymphomas. They all appear to be related to an infective cause (Epstein Barr Virus, Helicobacter pylori, hepatitis B virus). We hypothesize that a genetic bottleneck 30,000years ago at the Last Glacial Maximum could have resulted in unique genetic polymorphisms in Toll-like receptor 8, making East Asians more vulnerable to these infective associated cancers. This bottleneck could have been caused by the presence of malaria in the southern Himalayan conduit between central and East Asia; and only those with an attenuated innate immune response to the malarial parasite (perhaps reflected by the TLR8 polymorphism) were spared the ravages of cerebral malaria; allowing these people to cross into east Asia, but then rendering them susceptible to later endemic infections and their associated cancers. [Copyright &y& Elsevier]

Abstract: Size effects are observed within discontinuous fibre composites, such that the material properties change with the specimen volume. Representative volume elements (RVEs) are commonly used to simulate random fibre architectures for finite element analysis of discontinuous fibre composites. A series of simplified 2D RVE models have been created and studied in this paper, in order to determine the relationship between the critical RVE size and fibre length and volume fraction. All models are subjected to periodic boundary conditions, but average properties are extracted from an inner region offset from the model boundary by a distance equivalent to two fibre lengths. According to Saint–Venant’s principle, this offset removes the uncertainty associated with the approximate boundary conditions. A statistical stopping criterion has been adopted to determine the number of realisations required to achieve a representative set of elastic properties for each fibre architecture. The critical RVE side length is shown to be approximately four times the fibre length when considering convergence of the tensile and shear stiffnesses for the range of fibre lengths and volume fractions studied. [Copyright &y& Elsevier]

Abstract: A finite element method is presented to predict the flexural properties of resorbable phosphate glass fibre reinforced PLA composite bone plates. A novel method for meshing discontinuous fibre architectures is presented, which removes many of the limitations imposed by conventional finite element approaches. The model is used to understand the effects of increasing the span-to-thickness ratio for different fibre architectures used for PBG/PLA composites. A span-to-thickness ratio of 16:1 is found to be appropriate for materials with randomly orientated fibres, which agrees well with the test standard. However, for highly aligned materials the model indicates that a span-to-thickness ratio of 80:1 is required, in order to minimise the effects of shear deflection. The model is validated against flexural stiffness data from the literature for a range of polymers, fibres and fibre volume fractions. Generally there is less than 10% error between the FE predictions and experimental values. The model is subsequently used to perform a parametric study to understand what material developments are required to match the properties of PGF/PLA composites to cortical bone. It is concluded that alignment of the fibre is necessary to exceed the 20GPa target, since the current manufacturing methods limit the fibre length to ∼10mm, which consequently restricts the flexural modulus to ∼19GPa (at50% volume fraction). [Copyright &y& Elsevier]

Abstract: Background: Breast surgical site infections (SSIs) are major sources of postoperative morbidity and mortality, and it''s established that surveillance of risk factors is effective in reducing hospital-acquired infections. However, studies about risk factors for breast SSIs were still under controversy because of limited data, contradictory results and lack of uniformity. Materials and methods: We searched the electronic database of PubMed for case–control studies about risk factors for breast SSIs, and a meta-analysis was conducted. Results: Eight studies including 681 cases and 2064 controls were eligible, and data was combined if the risk factor was studied by at least two studies. Of the 20 possible risk factors involved, 14 were proved significant for SSIs as follows: increased age, hypertension, higher body mass index (BMI), diabetes mellitus, American society of anesthesiologists (ASA) 3 or 4, previous breast biopsy or operation, preoperative chemoradiation, conservation therapy versus other surgical approaches, hematoma, seroma, more intraoperative bleeding, postoperative drain, longer drainage time and second drainage tube placed. However, other factors like smoking habit, immediate reconstruction, axillary lymph node dissection, preoperative chemotherapy, corticosteroid usage and prophylactic antibiotic didn''t show statistical significance. Conclusions: This meta-analysis provided a list of predictable or preventable factors that could be taken measures to reduce the rate of breast SSIs and excluded some negligible factors. This could be useful for developing effective prevention and treatment policies for patients with SSIs and improving the overall quality of life. [Copyright &y& Elsevier]

Abstract: In part 1 of this 2 part paper a method is presented for generating RVE analyses of discontinuous fibre planar distributions of random discontinuous carbon fibre bundles, with no limitation to the fibre volume fraction. An embedded element approach is used to simplify mesh generation for the matrix phase. This approach is shown to yield errors of 1% compared with a more conventional unstructured mesh, whilst offering significant reductions in model size. Periodic boundary conditions are adopted, applying Saint-Venant’s principle to provide an approximation of the effective material properties within an inner RVE region, some distance away from the outer boundary of the model. The critical decay length of prescribing such boundary conditions is shown to be approximately two times the fibre length in all cases, when a heterogeneous material (rather than homogeneous material) is used to model the outer region. [Copyright &y& Elsevier]

Abstract: This is the second part in a series of papers investigating the size of representative volume elements for discontinuous carbon fibre composites. An ‘embedded cell’ finite element approach, outlined in Part 1, has been used to determine critical RVE sizes for materials with increasing fibre lengths and fibre volume fractions. Convergence of the results for mechanical properties were seen at RVE edge lengths of four times the fibre length (a/L =4), irrespective of the fibre volume fraction. The calculated Poisson’s ratios (v 12 and v 21) were largely independent of the RVE size. The critical RVE size is seen to be dependent on deterministic size effects and statistical size effects. Deterministic size effects are dominant for RVE sizes smaller than a/L =4 because of the presence of bridging fibres. Statistical size effects beyond a/L =4 were seen to be principally dependant on the level of fibre homogeneity and the departure from isotropy within the RVE, and these aspects were evaluated. An analytical model has been used to extrapolate the variance data to understand the most computationally efficient way of determining the critical RVE size. This study confirmed that it is more efficient to test fewer larger models than many smaller models, for the same level of statistical confidence (95%). [Copyright &y& Elsevier]

Abstract: Purpose: To evaluate the prognostic potential of serum CCL2 (sCCL2) and serum TNF-α (sTNF-α) in nasopharyngeal carcinoma (NPC) before treatment by analysing the expression of these two markers. Experimental design: Both sCCL2 and sTNF-α were prospectively detected in 297 NPC patients with enzyme-linked immunosorbent assay (ELISA) before treatment. The correlations between sCCL2 level or sTNF-α level and patient’s survival were evaluated. Results: For sCCL2, the 5-year overall survival (OS) and 5-year distant metastasis-free survival (DMFS) of high expression group and low expression group were 64% versus 81% and 67% versus 84% (P <0.05), respectively. For sTNF-α, the 5-year OS and 5-year DMFS of high expression group and low expression group were 62% versus 79% and 66% versus 82% (P <0.05), respectively. The 5-year OS and 5-year DMFS for both positive patients, one marker positive patient and both negative patients were 53% versus 77% versus 85% and 58% versus 80% versus 86% (P <0.05), respectively. Concentrations of sCCL2 and sTNF-α in patients with large skull base invasion were higher than those without or with small skull invasion (P <0.05). Patients who developed bone metastasis alone after radical treatment had higher pre-treatment concentrations of sCCL2 and sTNF-α than those without metastasis (P <0.001). Multifactorial Cox regression analyses demonstrated that T/N/M classification, chemotherapy, sCCL2 level and sTNF-α level were independent predictors of OS and DMFS of NPC patients. Conclusion: High expression levels of sCCL2 and sTNF-α predict bone invasion, post-treatment distant metastasis and poor overall survival in NPC patients. [ABSTRACT FROM AUTHOR]

Abstract: Background/Aim: The role of Notch-1 in human gastric carcinoma, one of the most common carcinomas of the human digestive tract, remains poorly characterised. Here, we investigated the effect and mechanism of Notch-1 activation on TNFα-induced apoptosis of human gastric carcinoma BGC-823 cells. Methods: Cell viabililty was measured by MTT assay. Apoptosis was detected by flow cytometry assay. Notch-1, Hes-1, caspase-3 p20 and NF-κB p65 expressions were assayed by Western blotting. NF-κB activation was tested by electrophoretic mobility shift assay (EMSA), and caspase-3 activation was tested by colorimetric assay. Results: BGC-823 cells underwent apoptosis following stimulation with TNFα. We found that Notch-1 was over-activated by overexpressing exogenous intracellular domain of Notch (ICN) via retrovirus-mediated gene transfer, and over-activated Notch-1 reduced the TNFα-induced growth suppression and apoptosis in BGC-823 cells. Down-regulation of Notch-1 by siRNA targeting Notch-1 enhanced TNFα-induced apoptosis in BGC-823 cells. As the molecular mechanism involved, we showed over-activated Notch-1 partially suppressed TNFα-induced activation of caspase-3. However, TNFα-induced activation of NF-κB was not affected by over-activated Notch-1. Conclusions: Our data indicate that over-activated Notch-1 significantly protects BGC-823 cells from TNFα-induced apoptosis, and this effect is mediated, at least in part, by decreasing activation of caspase-3 independent of NF-κB. [Copyright &y& Elsevier]

Abstract: During the encapsulation of electronic components stresses are generated due to curing effects and the difference in thermal shrinkage between molding compound and die. These residual stresses add up to the stresses generated during thermal cycling and mechanical loading and may eventually lead to product failure. In this paper we focus on three commercial molding compounds and analyze in detail the increase in elastic modulus and the change in viscoelastic behaviour during cure. This was done with a special shear tool which allows to measure mechanical properties with sufficient accuracy in the liquid as well as in the solid state. The cure dependent viscoelastic material behaviour was modeled using a cure dependent shift factor and rubber modulus. The viscoelastic behaviour of the molding compounds is also shown not to be stable. During postcure the materials slowly continue to crosslink thereby systematically changing their viscoelastic behaviour. The material models presented here therefore only account for the initial curing stage and do not include postcure. [Copyright &y& Elsevier]

The fundamental recovery technique for some medium failures in a database system is regularly carried out by executing a full backup that takes all copies of updated files. However, the overhead of such full backup becomes sometimes very large in a massive database system. To lessen the overhead of backups, an incremental backup with small overhead, which takes only copies of newly updated files, is usually adopted in most database systems. However, the overhead of an incremental backup increases in proportion to the total amount of updated files. It would be necessary to determine when to make full backups. This paper proposes a stochastic model with incremental and full backups: the expected costs incurred for two backups are obtained, and an optimal full backup interval which minimizes them is discussed. It is shown that an optimal interval is given by a finite and unique solution of an equation under suitable conditions. Finally, a numerical example is given and some useful discussions are made. [Copyright &y& Elsevier]

This paper considers replacement and minimal repair polices for an extended cumulative damage model with maintenance at each shock: shocks occur at a nonhomogeneous Poisson process. A system undergoes maintenance at each shock when the total damage does not exceed a failure level K, undergoes minimal repair at each shock when the total damage exceeds a failure level K, and is replaced at time T&ast; or at failure N&ast; whichever occurs first. The expected cost rate is obtained and the optimal T&ast; and N&ast; minimizing the expected cost are analytically discussed. It is shown that this model would be applied to the backup of secondary storage files in a database system as an example. [Copyright &y& Elsevier]

All automatic teller machines (ATMs) in a bank operate unmanned on weekends and holidays, and an automatic monitoring system continuously watches the operation of ATMs through the telecommunication network. There are two kinds of troubles according to the installed places of ATMs. One is the trouble which occurs inside the branch of a bank where ATMs operate manned except on weekends and holidays, and the other is the one which occurs outside the branch where ATMs always operate unmanned. Two kinds of breakdowns are introduced, and the expected cost for an unmanned operation period is obtained. A maintenance policy which minimizes the expected cost is analytically derived. Finally, a numerical example is given and some useful discussions are made. [Copyright &y& Elsevier]

Bacterial spores from raw milk that survive the pasteurization process are responsible for half of all the spoilage of fluid milk. Bactofugation has received more attention as a nonthermal method that can reduce the presence of bacterial spores in milk and with it the spoilage of fluid milk. The objective of this work was to determine the effectiveness of bactofugation in removing spores from raw milk and estimate the effect the spore removal could have on shelf-life of fluid milk. The study was conducted in a commercial fluid milk processing facility where warm spore removal was performed using one-phase bactofuge followed by warm cream separation and high temperature, short time pasteurization. Samples from different stages of fluid milk processing with and without the use of bactofuge were tested for total plate count, mesophilic spore count, psychrotolerant spore count (PSC), and somatic cell count. Results were evaluated to determine the count reductions during different stages of fluid milk processing and compare counts in fluid milk processed with and without bactofugation. Bactofugation on average reduced the total plate count by 1.81 ± 0.72 log cfu/mL, mesophilic spore count by 1.08 ± 0.71 log cfu/mL, PSC by 0.86 ± 0.59 log cfu/mL, and somatic cell count by 135,881 ± 43,942 cells/mL. Psychrotolerant spore count in final pasteurized skim milk processed with and without bactofugation was used to predict the shelf-life of the pasteurized skim milk using the Monte Carlo simulation model. Although PSC in the initial raw milk was already low (−0.63 ± 0.47 log cfu/mL), the predicted values from the simulation model showed that bactofugation would extend the shelf-life of pasteurized skim milk by approximately 2 d. The results of this study will directly help fluid milk processors evaluate the benefits of using bactofugation as an intervention in their plants, and also demonstrate the benefits of using mathematical modeling in decision making. [ABSTRACT FROM AUTHOR]

Duchenne muscular dystrophy (DMD) is characterized by severe progressive muscle weakness, loss of ambulation (LOA) and early mortality. The study objective was to estimate the age at key milestones among commercially- or Medicaid-insured DMD patients in the US. [Extracted from the article]