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Abstract With the continuous and rapid growth of transport demand, scheduling strategy of warehouse has become a key issue in the field of logistics transportation. The structural differences of the warehouse, the automated storage and retrieval system (AS/RS) model and the two‐end dual stackers scheduling model (TDSM) are considered, and a new improved genetic algorithm (NIGA) is proposed. It can adjust the algorithm structure according to the density of population fitness value, and effectively optimize the stacker path. In the TDSM, an improved anti‐collision principle is proposed to avoid collision of two stackers. Besides, combined with the optimal anti‐collision boundary inspection mechanism, the best working area for the two stackers is allocated by using NIGA. Finally, the new improved GA is compared with GA and the adaptive GA on specific storage and retrieval tasks. The simulation results show that the proposed NIGA well outperforms other GAs in most instances, which indicates that it is an effective approach for the AS/RS and the TDSM scheduling optimization problem.

With the continuous and rapid growth of transport demand, scheduling strategy of warehouse has become a key issue in the field of logistics transportation. The structural differences of the warehouse, the automated storage and retrieval system (AS/RS) model and the two‐end dual stackers scheduling model (TDSM) are considered, and a new improved genetic algorithm (NIGA) is proposed. It can adjust the algorithm structure according to the density of population fitness value, and effectively optimize the stacker path. In the TDSM, an improved anti‐collision principle is proposed to avoid collision of two stackers. Besides, combined with the optimal anti‐collision boundary inspection mechanism, the best working area for the two stackers is allocated by using NIGA. Finally, the new improved GA is compared with GA and the adaptive GA on specific storage and retrieval tasks. The simulation results show that the proposed NIGA well outperforms other GAs in most instances, which indicates that it is an effective approach for the AS/RS and the TDSM scheduling optimization problem. [ABSTRACT FROM AUTHOR]

Posturography is a tool for quantitative measurement of balance in various static and dynamic test conditions. Current medical grade Posturography systems are very costly and rare outside research institutes. The Wii Balance Board is an inexpensive gaming device which works on similar principles and uses the center of pressure of an individual as an input for motion-controlled gaming. The aim of this study was to assess the validity of using a gaming platform (Wii Balance Board) as a substitute to medical grade Posturography machine. The objectives were to compare the measures of postural sway obtained from a gaming platform with those from a medical grade Posturography machine and to demonstrate a low-cost method of analysis of balance using the gaming platform. Descriptive Observational study. Individuals aged 18–65 years and having no apparent dysfunction of balance were assessed objectively using Wii Balance Board and Medical-grade Posturography machine. A program was developed in Scilab for computation of sway parameters. The results were compared in terms of correlation coefficient, Bland-Altmann plots, and ability to detect abnormal sway. A Pearson's correlation coefficient ranging from 0.53–0.91 was observed in various test conditions, with an overall value of 0.62 between the results of the two machines. The sensitivity was 69.39%, specificity was 73.16%, positive predictive value 24.29%, negative predictive value 95.07%, and accuracy 72.75%. Thus, we can conclude that the Wii Balance Board can be used as a low-cost substitute to medical grade Posturography machine for quantification of balance in situations where precise measurement of balance is not required. [ABSTRACT FROM AUTHOR]

Translating progress in neuroscience into clinical benefits for patients with psychiatric disorders is challenging because it involves the brain as the most complex organ and its interaction with a complex environment and condition. Dealing with such complexity requires powerful techniques. Computational neuroscience approach to psychiatry integrates multiple levels and types of simulation, analysis and computation according to the different types of computational models to enhance comprehending, prediction and treatment of psychiatric disorder. This approach comprises two approaches: theory-driven and data-driven. In this review, we focus on recent advances in theory-driven approaches that mathematically and mechanistically examine the relationships between disorder-related changes and behavior at different level of brain organization. We discuss recent progresses in computational neuroscience models that relate to psychiatry and show how principles of neural computational modeling can be employed to explain psychopathology. [ABSTRACT FROM AUTHOR]

Abstract Background Circadian clock alterations were poorly reported in trauma patients, although they have a critical role in human physiology. Core body temperature is a clinical variable regulated by the circadian clock. Our objective was to identify the circadian temperature disruption in trauma patients and to determine whether these disruptions were associated with the 28-day mortality rate. Methods A retrospective and observational single-center cohort study was conducted. All adult severe trauma patients admitted to the intensive care unit of Aix Marseille University, North Hospital, from November 2013 to February 2018, were evaluated. The variations of core body temperature for each patient were analyzed between days 2 and 3 after intensive care unit admission. Core body temperature variations were defined by three parameters: mesor, amplitude, and period. A logistic regression model was used to determine the variables influencing these three parameters. A survival analysis was performed assessing the association between core body temperature rhythm disruption and 28-day mortality rate. A post hoc subgroup analysis focused on the patients with head trauma. Results Among the 1584 screened patients, 248 were included in this study. The period differed from 24 h in 177 (71%) patients. The mesor value (°C) was associated with body mass index and ketamine use. Amplitude (°C) was associated with ketamine use only. The 28-day mortality rate was 18%. For all trauma patients, age, body mass index, intracranial hypertension, and amplitude were independent risk factors. The patients with a mesor value 0.6 °C (p

There are few published examples of absolute risk estimated from epidemiologic data subject to censoring and competing risks with adjustment for multiple confounders. We present an example estimating the effect of injection drug use on 6-year risk of acquired immunodeficiency syndrome (AIDS) after initiation of combination antiretroviral therapy between 1998 and 2012 in an 8-site US cohort study with death before AIDS as a competing risk. We estimate the risk standardized to the total study sample by combining inverse probability weights with the cumulative incidence function; estimates of precision are obtained by bootstrap. In 7,182 patients (83% male, 33% African American, median age of 38 years), we observed 6-year standardized AIDS risks of 16.75% among 1,143 injection drug users and 12.08% among 6,039 nonusers, yielding a standardized risk difference of 4.68 (95% confidence interval: 1.27, 8.08) and a standardized risk ratio of 1.39 (95% confidence interval: 1.12, 1.72). Results may be sensitive to the assumptions of exposure-version irrelevance, no measurement bias, and no unmeasured confounding. These limitations suggest that results be replicated with refined measurements of injection drug use. Nevertheless, estimating the standardized risk difference and ratio is straightforward, and injection drug use appears to increase the risk of AIDS.

ObjectivesIn this paper, we present an efficient method to visualize computed tomography (CT) datasets using ambient occlusion, which is a global illumination technique that adds depth cues to the output image. We can change the transfer function (TF) for volume rendering and generate output images in real time.MethodsIn preprocessing, the mean and standard deviation of each local vicinity are calculated. During rendering, the ambient light intensity is calculated. The calculation is accelerated on the assumption that the CT value of the local vicinity of each point follows the normal distribution. We approximate complex TF forms with a smaller number of connected line segments to achieve additional acceleration. Ambient occlusion is combined with the existing local illumination technique to produce images with depth in real time.ResultsWe tested the proposed method on various CT datasets using hand-drawn TFs. The proposed method enabled real-time rendering that was approximately 40 times faster than the previous method. As a result of comparing the output image quality with that of the conventional method, the average signal-to-noise ratio was approximately 40 dB, and the image quality did not significantly deteriorate.ConclusionsWhen rendering CT images with various TFs, the proposed method generated depth-sensing images in real time.

Many community-based studies of acute child illness rely on cases reported by caregivers. In prior investigations, researchers noted a reporting bias when longer illness recall periods were used. The use of recall periods longer than 2-3 days has been discouraged to minimize this reporting bias. In the present study, we sought to determine the optimal recall period for illness measurement when accounting for both bias and variance. Using data from 12,191 children less than 24 months of age collected in 2008-2009 from Himachal Pradesh in India, Madhya Pradesh in India, Indonesia, Peru, and Senegal, we calculated bias, variance, and mean squared error for estimates of the prevalence ratio between groups defined by anemia, stunting, and underweight status to identify optimal recall periods for caregiver-reported diarrhea, cough, and fever. There was little bias in the prevalence ratio when a 7-day recall period was used (

The B-lymphocyte lineage is a leading system for analyzing gene regulatory networks (GRNs) that orchestrate distinct cell fate transitions. Upon antigen recognition, B cells can diversify their immunoglobulin (Ig) repertoire via somatic hypermutation (SHM) and/or class switch DNA recombination (CSR) before differentiating into antibody-secreting plasma cells. We construct a mathematical model for a GRN underlying this developmental dynamic. The intensity of signaling through the Ig receptor is shown to control the bimodal expression of a pivotal transcription factor, IRF-4, which dictates B cell fate outcomes. Computational modeling coupled with experimental analysis supports a model of 'kinetic control', in which B cell developmental trajectories pass through an obligate transient state of variable duration that promotes diversification of the antibody repertoire by SHM/CSR in direct response to antigens. More generally, this network motif could be used to translate a morphogen gradient into developmental inductive events of varying time, thereby enabling the specification of distinct cell fates.

PurposeThe purpose of this work was to gather preliminary data in normals and dry eye subjects, using a new, non-invasive imaging platform to measure the thickness of pre-corneal tear film.MethodsHuman subjects were screened for dry eye and classified as dry or normal. Tear film thickness over the inferior paracentral cornea was measured using laser illumination and a complementary metal-oxide-semiconductor (CMOS) camera. A previously developed mathematical model was used to calculate the thickness of the tear film by applying the principle of spatial auto-correlation function (ACF).ResultsMean tear film thickness values (±SD) were 3.05 μm (0.20) and 2.48 μm (0.32) on the initial visit for normals (n=18) and dry eye subjects (n=22), respectively, and were significantly different (p

Fat tailed statistics and power-laws are ubiquitous in many complex systems. Usually the appearance of of a few anomalously successful individuals (bio-species, investors, websites) is interpreted as reflecting some inherent "quality" (fitness, talent, giftedness) as in Darwin's theory of natural selection. Here we adopt the opposite, "neutral", outlook, suggesting that the main factor explaining success is merely luck. The statistics emerging from the neutral birth-death-mutation (BDM) process is shown to fit marvelously many empirical distributions. While previous neutral theories have focused on the power-law tail, our theory economically and accurately explains the entire distribution. We thus suggest the BDM distribution as a standard neutral model: effects of fitness and selection are to be identified by substantial deviations from it.

Systems of fractional differential equations (SFDE) have been increasingly used to represent physical and control system, and have been recently proposed for use in pharmacokinetics (PK) by (J Pharmacokinet Pharmacodyn 36:165-178, 2009) and (J Phamacokinet Pharmacodyn, 2010). We contribute to the development of a theory for the use of SFDE in PK by, first, further clarifying the nature of systems of FDE, and in particular point out the distinction and properties of commensurate versus non-commensurate ones. The second purpose is to show that for both types of systems, relatively simple response functions can be derived which satisfy the requirements to represent single-input/single-output PK experiments. The response functions are composed of sums of single- (for commensurate) or two-parameters (for non-commensurate) Mittag-Leffler functions, and establish a direct correspondence with the familiar sums of exponentials used in PK.

Background: Circadian clock alterations were poorly reported in trauma patients, although they have a critical role in human physiology. Core body temperature is a clinical variable regulated by the circadian clock. Our objective was to identify the circadian temperature disruption in trauma patients and to determine whether these disruptions were associated with the 28-day mortality rate. Methods: A retrospective and observational single-center cohort study was conducted. All adult severe trauma patients admitted to the intensive care unit of Aix Marseille University, North Hospital, from November 2013 to February 2018, were evaluated. The variations of core body temperature for each patient were analyzed between days 2 and 3 after intensive care unit admission. Core body temperature variations were defined by three parameters: mesor, amplitude, and period. A logistic regression model was used to determine the variables influencing these three parameters. A survival analysis was performed assessing the association between core body temperature rhythm disruption and 28-day mortality rate. A post hoc subgroup analysis focused on the patients with head trauma. Results: Among the 1584 screened patients, 248 were included in this study. The period differed from 24 h in 177 (71%) patients. The mesor value (°C) was associated with body mass index and ketamine use. Amplitude (°C) was associated with ketamine use only. The 28-day mortality rate was 18%. For all trauma patients, age, body mass index, intracranial hypertension, and amplitude were independent risk factors. The patients with a mesor value < 36.9 °C (p < 0.001) and an amplitude > 0.6 °C (p < 0.001) had a higher 28-day mortality rate. Among the patients with head trauma, mesor and amplitude were identified as independent risk factors (HR = 0.40, 95% CI [0.23–0.70], p = 0.001 and HR = 4.73, 95% CI [1.38–16.22], p = 0.01). Conclusions: Our results highlight an association between core body temperature circadian alteration and 28-day mortality rate. This association was more pronounced in the head trauma patients than in the non-head trauma patients. Further studies are needed to show a causal link and consider possible interventions. [ABSTRACT FROM AUTHOR]

To study the behavior of cerebral physiological parameters and to further the understanding of the functional magnetic resonance imaging (fMRI) blood-oxygen-level-dependent (BOLD) effect, multisource frequency-domain near-infrared and BOLD fMRI signals were recorded simultaneously during motor functional activation in humans. From the near-infrared data information was obtained on the changes in cerebral blood volume and oxygenation. To relate our observations to changes in cerebral blood flow the well-known "balloon" model was employed. Our data showed that the deoxyhemoglobin concentration is the major factor determining the time course of the BOLD signal. The increase in cerebral blood oxygenation during functional activation is due to an increase in the velocity of blood flow, and occurs without significant swelling of the blood vessels.

Background: Based on the studies which have investigated conscious and unconscious processes, simple arithmetic operations such as addition and multiplication can be automatically processed in the brain and affect subsequent responses. However, most studies have focused on addition and multiplication of one-digit numbers. In this research we used subliminal priming paradigm to assess automatic retrieval of subtraction operation for the first time. Objectives: The aim of this study was to use a subliminal priming paradigm in a naming task and investigate the automatic and unconscious processing of the subtraction operation. Research of this kind can help us determine different levels of unconscious and conscious processing in the brain. Materials and Methods: Forty-five graduate student in psychology at the Faculty of Education and Psychology, University of Tabriz (between 18 and 25 years; mean 20.7, SD=2.7) participated in the experiment. For presenting the stimuli, an open-source software (DMDX) was used and presented on a 15-inch monitor. In the experiment, in the congruent condition, the prime was congruent with the target in terms of subtraction calculation result and in the incongruent condition there was no logical connection between the two stimuli. The vocal reaction time (RT) of participants was recorded and paired t-test analysis was conducted for comparison of the two conditions. Results: The data showed that naming the target by the participants is carried out faster when the two stimuli are congruent with each other in terms of the result of the operation. Conclusion: These findings may have implications on the levels of mathematical operations. In conclusion it seems that the calculation of one-digit numbers can happen at the level of simple neuronal circuits and may be carried out without conscious-awareness. The findings confirm the fact that calculating subtraction for one-digit numbers does not require conscious effort and can be processed automatically.

Oxygen quenching experiments were carried out on zincprotoporphyrin IX reconstituted myoglobin (MbFe-->Zn) at different temperatures and two solvent viscosities. The data were fit to a dynamic model for quenching of fluorophores in protein interiors previously presented (Biophysical J., 45 (1984) 789-794). The parameters associated with the oxygen entry rate (k+), exit rate (k-), and migration rate (chi) in the protein were obtained at six temperatures and two viscosities (1 and 8 cp), along with the activation enthalpies associated with the above rates (k+ and k-). The partition coefficient (alpha) was calculated at each temperature along with the free energy, delta G0, associated with this partition. The rate parameters (k+, k-, chi) and the partition coefficient (alpha) have also been determined for the sample in 40% sucrose (8 cp), to evaluate the effect of bulk solvent viscosities on these values. The steady-state Stern-Volmer quenching plot was calculated using the rate parameters obtained from the analysis (of the dynamic model). Comparison of the Stern-Volmer points obtained using the dynamic model and those obtained experimentally showed excellent agreement.

Recent crystallographic studies have shown that both backbone and side-chain adjustments occur when different core-packing arrangements are accommodated in proteins. Thus, modeling methods, which have typically considered only side-chain adjustments, must now also account for backbone movements to accurately predict the energies and structures of mutated or designed proteins. The 'plasticity' of protein cores demonstrated by random mutagenesis simplifies protein design by increasing the likelihood of identifying alternative core sequences.

Internal strain is known to be one of the contributors to plantar soft tissue damage. However, due to challenges related to measurement techniques, there is a paucity of research investigating the strain within the plantar soft tissue during daily weight-bearing activities. Therefore, the main aim of this study was to develop a non-invasive method for predicting heel pad strain during loading. An ultrasound indentation technique along with a mathematical model was employed to calculate visco-hyperelastic structural coefficients from the results of cyclic-dynamic indentation and stress-relaxation tests. Subject-specific structural coefficients of heel pads were calculated from twenty participants along with the assessment of plantar pressure. The average difference between the predicted and the measured force during the cyclic-dynamic indentation test was only 5.8%. Moreover, the average difference between the predicted and the in vivo strain during walking was 14%. No statistically significant correlation was observed between maximum strain and peak plantar pressure during walking; indicating that the measurement of strain along with plantar pressure can improve our understanding of the mechanical behaviour of the plantar soft tissue. [ABSTRACT FROM AUTHOR]

Objective To investigate the cortical activation patterns and their correlation with behavioristics during simple multiplication in Chinese younger and older adults. Methods Functional magnetic resonance imaging (fMRI) was performed as healthy younger and older participants resolving arithmetic and control problems. Results Totally 39 right-handed healthy adults were recruited in this study, including 19 (11 females, 8 males) younger and 20 (12 females, 8 males) older subjects. Age (P = 0.000) was significantly different between 2 groups, and no significant difference was observed in years of education (P = 0.125) and IQ scores (P = 0.921). The accuracy for simple multiplication (P = 0.880) and control task (P = 0.142) were not significantly different between 2 groups, however differences were observed in reaction time for experimental (P = 0.005) and control (P = 0.000) tasks. In younger group, activation in right hemisphere included inferior parietal lobule with an extending to the intraparietal sulcus and superior/middle temporal gyrus, precentral gyrus, premotor cortex and prefrontal cortex. Activation of supramarginal gyrus, angular gyrus, temporal lobe was found in the left. And activation in medial cingulate gyrus, precuneus, parahippocampal gyrus, uncus, and supplementary motor area (SMA) was also observed. In older group, supramarginal gyrus, inferior parietal lobule, precentral gyrus, premotor cortex and prefrontal cortex were activated in the right hemisphere. Left angular gyrus, supramarginal gyrus, precentral gyrus, premotor cortex, insula and prefrontal cortex were also activated, as well as cingulate gyrus, paracentral lobule and prefrontal cortex in the medial part. The conjunction analysis of the fMRI data revealed in a distributed network consisting of inferior parietal area, precuneus, precentral/postcentral gyrus and prefrontal lobe, as well as some subcortical areas. Conclusions The major components of the network subserving simple multiplication are not significantly affected by advancing age, in addition activation in older people concentrates to task related parietal area. doi: 10.3969/j.issn.1672-6731.2014.03.010

To investigate the reliability and validity of a novel mathematical model for quantitative muscle ultrasound of the first dorsal interosseous (FDI) muscle. This was a repeated-measures, cross-sectional study. For each subject, three axial images were separately acquired from the right FDI by three junior sonographers. Three repeat FDI strength measurements per subject were subsequently taken with pinch grip dynamometry. Mathematical modeling and statistical analysis was performed on SPSS by one ultrasonographer. Single center, research institute as part of a tertiary care hospital. Participants were healthy volunteers recruited from the local university community. n=20 (M=9. F=11), mean age= 27, SD= 6.5. N/A. Outcome measures were acquired for each of the three traditional analysis techniques and the novel mathematical model used to determine muscle thickness. Firstly, inter-rater reliability amongst the three junior sonographers was assessed with intraclass correlation. Secondly, validity was assessed via a linear regression analysis with pinch grip dynamometry strength measures. The validity revealed profoundly higher correlation for the new mathematical model (R-Squared=0.70) compared to the traditional analysis techniques (R-Squared=0.42-0.50). Inter-rater reliability is higher with the new mathematical model (ICC range: 0.839-0.964) compared to traditional analysis techniques (ICC range: 0.671-0.946). Visual modeling qualitatively contrasts the robustness of new and traditional models to variability in FDI morphologies commonly seen across the population. The new mathematical model has higher validity and higher inter-rater reliability compared to traditional methods for the ultrasound analysis of axial FDI muscle thickness. Visual modeling depicts the limitations of the traditional methods to account for variations in muscle eccentricity and convexity across the population. Visual modeling further illustrates that the new mathematical model is more robust across a wider range of FDI architectural parameters. None. [ABSTRACT FROM AUTHOR]

Background: The successful identification of genetic loci for complex traits in genome-wide association studies (GWAS) has resulted in thousands of GWAS summary statistics becoming publicly available for hundreds of complex traits from multiple cohorts and studies. Visualisation is an important aid for interpreting, comparing, validating, and obtaining an overview of large amounts of data. However, the current software is limited in its ability and flexibility to annotate and simultaneously display multiple GWAS results which is useful when interpreting and comparing association results. Therefore, I created the topr R package to facilitate visualisation, annotation, and comparisons of single or multiple GWAS results. It contains functions tailored for viewing and analysing GWAS results., Results: topr provides a fast and elegant visual display of association results, along with the annotation of association peaks with their nearest gene. Association results from multiple analyses can be viewed simultaneously over the entire genome or in a more detailed regional view along with gene information. Users can perform the essential steps of visually exploring and annotating association results and generating elegant publication-ready plots., Conclusions: topr is developed as a package for the R statistical computing environment, released under the GNU General Public License, and is freely available on the Comprehensive R Archive Network ( http://cran.r-project.org/package=topr ). The source code is available at GitHub ( https://github.com/totajuliusd/topr ). topr provides several advantages and advances over the current alternatives, particularly in its gene annotation functionality and customisable display of single- or multiple-association results. With topr, I provide a flexible tool with multiple features to aid in the analysis and evaluation of GWAS association results., (© 2023. The Author(s).)