Considerable Time Gain Research Articles

Optimization of a microreactor core's dimensions using metaheuristic methods

This article proposes the use of the multi-group diffusion equations with four groups to determine the dimensions of the microreactor of the TERRA project. With this intent, the values of the radius and height of the cylinder that represents the core, as well as its enrichment were optimized through a framework called LOF. This tool has several metaheuristics methods already implemented, which provides a considerable time gain. So any particular method implemented, or a combination of some of them, could be utilized without any concerns regarding implementation time. In addition to the application of the metaheuristic methods for the proposed optimization, there was also a concern about altering the search parameters used in each of the metaheuristics, which eventually caused an improvement in the results. With this method, the radius and height dimensions achieved were quite reasonable for a microreactor. As for the enrichment, the value of 19.75% was achieved, limited by the Non-Proliferation Treaty.

Objective frequency-specific hearing thresholds definition for medicolegal purposes in case of occupational NIHL: ASSR outperforms CERA

Audiological use of the 40 Hz-ASSR (auditory steady state responses) could be valuable for objectively estimating the frequency-specific threshold in adults undergoing an expertise examination for medicolegal and/or compensation purposes. The present prospective study was set up to clarify the relationship between the thresholds obtained by cortical evoked response audiometry (CERA) and by 40 Hz-ASSR, in the same ears, within a large homogeneous sample of 164 subjects (328 ears) with NIHL and well documented exposure to noise. All these subjects claimed financial compensation for occupational NIHL, and there was a suspicion of exaggeration of the reported NIHLs. ASSR thresholds show a good correlation with the CERA thresholds. However, a systematic shift is noticed, ASSR thresholds being on average (1–2 – 3 kHz) 4.38 dB lower (i.e. showing less hearing loss) than CERA thresholds. Moreover, the binaural multiple ASSR technique allows a considerable time gain when compared to the CERA.

Influence of gas flow oscillation on the efficiency of particulate solids treatment in a circulating fluidized bed

Apparatuses with fluidized bed are widely used in the solid fuel energetic, chemical and other industries. In particular, fluidized bed furnaces play the increasing role for thermo-chemical treatment and burning the solid fuels including bio-fuels. The use of pulsating gas flows is one of the possible ways to intensify the process of gas-particle interaction. However, the efficiency of the way is not always obvious, and new approaches are needed for preliminary estimation of its advantages. The method of mathematical modeling is used to solve the above problem. The model is based on the set of differential equations of a single particle motion in the upstream gas flow with variable with time velocity, and with variable with time particle properties due to this or that thermo-physical or chemical process of gas-particle interaction. The study of influence of the process parameters on its efficiency is done by numerical methods. The model of the effect of oscillations in the gas flow on the efficiency of particle processing in a circulating fluidized bed has been developed. The necessary time for enough particle treatment is compared for different amplitude and frequency of gas flow oscillation. The most considerable gain in time is being reached for the strong dependence of the reaction rate constant on the velocity of flow around the particle. In this case the optimum frequency of oscillations exists that give the maximum gain in time. The growth of the amplitude leads to the monotonic increase of the gain in time, or gives the optimum amplitude. Transition to the pulsating gas flow in a circulating fluidized bed reactor leads to considerable gain in time of particle treatment only in the case of strong dependence of the reaction rate constant on the velocity of flow around the particle. In this case the optimum frequency and amplitude of oscillation exist that gives the maximum gain in time.

Next Generation Sequencing Is a Useful Tool for the Diagnosis of Congenital/Idiopathic Erythrocytoses

Introduction: Erythrocytoses are characterized by an elevated red cell mass. The most widely studied disease is Polycythemia Vera (PV), a myeloproliferative neoplasm due to the acquired JAK2-V617F mutation. However, other types of erythrocytoses exist and are of major importance. They can be either inherited (Congenital Erythrocytosis-CE) or diagnosed in adult patients with no family history (Idiopathic Erythrocytosis-IE). CE/IE are not associated with myeloproliferation but they can be associated with severe thrombo-embolic or haemorrhagic events, pulmonary arterial hypertension and, rarely, tumours. The 8 genes identified so far as causing CE lie at the crossroads of major biological pathways (metabolism, inflammation, oncogenesis) and are implicated in multiple diseases. These genes are involved (i) in the regulation of the hypoxia pathway, PHD2 (also called EGLN1), HIF-2A (EPAS1), VHL, (ii) in proliferation and differentiation of erythroid progenitors (EPOR), or (iii) in mature cell function, haemoglobins (HBB, HBA1, HBA2) or bisphosphoglyceratemutase (BPGM). However, in 80% of cases the cause remains unknown meaning that no proper diagnosis can be made, no prognosis or advice can be provided to CE/IE patients and their families, and no curative treatment exists.Method: We created and developed a national network in France to (i) identify, (ii) collect and (iii) analyze the genomic abnormalities in patients suspected of CE/IE. The selection of patients was performed using a clinical and biological data sheet including mandatory further tests in order to exclude patients with PV or obvious secondary erythrocytosis related to lung, cardiac or renal disorder. Next generation sequencing (NGS) has been used to analyse the presence of mutations in 17 genes (VHL, PHD1, PHD2 and PHD3, HIF1A, HIF2A, HIF3A, FH, BPGM, and 8 other candidate genes). SureDesign software (Agilent, Santa Clara, CA) was used to design the custom HaloPlex capture assay. For sequence capture, HaloPlex Target Enrichment System Kit (AgilentR), for Illumina sequencing was used, according to the manufacturer's instructions.Results: To date, samples from 103 patients have been recorded, among whom 46 have been tested using NGS approach. Variants in 10 (21%) patients [9 males and 1 female ; median age 50 y. (12-71)] with unknown significance have been detected, including 4 in PHD genes, 5 in HIF genes, and 1 in JAK2 gene.In patients with variants, a familial history of erythrocytosis was noted in 2. No independent thrombotic complication was reported in the 10 patients. The proportion of variants detected (21%) was close to the classical rate of genomic abnormalities usually observed in CE/IE. In 2 patients (one with a PHD2 and one with a JAK2 variants), the erythropoietin was low, whereas for the others, the erythropoietin was normal. Of note, the median age of the patients was surprisingly high, suggesting that the diagnostic was not previously performed due to the absence of available tests. Indeed, the diagnostic approaches using NGS techniques led to a considerable time gain and facilitated the identification of certain molecular abnormalities associated with CE/IEConclusion: NGS is a useful tool to explore mutations in CE/IE, but identifies genetic variants in only 20% of patients with such disorder. In vitro, in cellulo and in vivo (including zebrafish models) functional studies are currently performed to validate the clinical relevance of these variants. Further exams including whole exome sequencing are planned to achieve a right diagnosis in the 80% remaining CE/IE patients without identified genomic abnormalities. DisclosuresNo relevant conflicts of interest to declare.

Evaluation of a Scalable Information Analytics System for Enhanced Situational Awareness in Mass Casualty Events.

We investigate the utility of DIORAMA-II system which provides enhanced situational awareness within a disaster scene by using real-time visual analytics tools and a collaboration platform between the incident commander and the emergency responders. Our trials were conducted in different geographical areas (feature-rich and featureless regions) and in different lighting conditions (daytime and nighttime). DIORAMA-II obtained considerable time gain in efficiency compared to conventional paper based systems. DIORAMA-II time gain was reflected in reduction of both average triage time per patient (up to 34.3% average triage time reduction per patient) and average transport time per patient (up to 76.3% average transport time reduction per red patient and up to 66.3% average transport time reduction per yellow patient). In addition, DIORAMA-II ensured that no patients were left behind or transported in the incorrect order compared to the conventional method which resulted in patients being left behind and transported in the incorrect order.

A treatment planning and delivery comparison of volumetric modulated arc therapy with or without flattening filter for gliomas, brain metastases, prostate, head/neck and early stage lung cancer

Background. Flattening filter-free (FFF) beams are an emerging technology that has not yet been widely implemented as standard practice in radiotherapy centers. To facilitate the clinical implementation of FFF, we attempted to elucidate the difference in plan quality and treatment delivery time compared to flattening filter beams (i.e. standard, STD) for several patient groups. We hypothesize that the treatment plan quality is comparable while the treatment delivery time of volumetric modulated arc therapy (VMAT) is considerably shorter using FFF beams, especially for stereotactic treatments.Methods. A total of 120 patients treated for head and neck (H&N) tumors, high-grade glioma, prostate cancer, early stage lung cancer and intra-cranial metastatic disease (both single and multiple metastases) were included in the study. For each cohort, 20 consecutive patients were selected. The plans were generated using STD- and FFF-VMAT for both 6 MV and 10 MV, and were compared with respect to plan quality, monitor units and delivery time using Wilcoxon signed rank tests.Results. For H&N and high-grade gliomas, there was a significant difference in homogeneity index in favor for STD-VMAT (p < 0.001). For the stereotactic sites there were no differences in plan conformity. Stereotactic FFF-VMAT plans required significantly shorter delivery time compared to STD-VMAT plans (p < 0.001) for higher dose per fraction, on average 54.5% for 6 MV and 71.4% for 10 MV. FFF-VMAT generally required a higher number of MU/Gy (p < 0.001), on average 7.0% for 6 MV and 8.4% for 10 MV.Conclusion. It was generally possible to produce FFF-VMAT plans with the same target dose coverage and doses to organs at risk as STD-VMAT plans. Target dose homogeneity tended to be somewhat inferior for FFF-VMAT for the larger targets investigated. For stereotactic radiotherapy, FFF-VMAT resulted in a considerable time gain while maintaining similar plan quality compared to STD beams.

Monolithic Columns: The New Era in the Analysis of Organic Compounds by Liquid Chromatographic Techniques

The increasing demand for ultra-fast separations has motivated the development of new materials in the field of chromatographic stationary phases. Since High Performance Liquid Chromatography is a powerful and popular technique, the importance of improving existing supports, as well as the development of new types of columns is more than profound. The advent of monolithic columns offered new practical possibilities for decreasing retention times and/or increasing column efficiencies, while pressure restriction was significantly eliminated. Monolithic columns are prepared by means of a polymerization process from either organic polymers, such as polymethacrylates, polystyrenes or from inorganic polymers, such as silica. Highly porous rods of silica with a bimodal pore structure consist of macropores and mesopores. The former consist of a dense network of pores, while the latter form contain fine porous structure of the column. This structure dictates the major chromatographic features of monolithic columns. Since many analytical methods employing conventional columns already exist, it is very challenging to study their transfer at similar or higher flow rates using monolithic rods with a considerable gain in time. Applications of analytical methods in organic analysis employing monoliths as stationary phase include pharmaceuticals, biofluids, food matrices, environmental samples, biochemical species, proteomics etc. Several additional application modes of monolithic columns have been explored. An emergence of applications is expected to continue as long as more experience is gained with monolithic column technology. Such an attempt has been prompted also by the need of reduction in organic solvent consumption, in the frame of environmental friendly methods. Keywords: Monolithic columns, HPLC, organic compounds, analysis, monoliths, hydrophilic interaction chromatography, HILIC, polymethacrylate monoliths, capillary electrochromatogra-phy, CEC, electroosmotic flow, EOF, Pentaerythritol diacrylate monostearate, PEDAS, 2-sulphoethyl methacry-late, SEMA, ethylene glycol dimethacrylate, EDMA, Diazepam, desmethyldiazepam, oxazepam, temazepam, Amoxicillin, clavulanic acid, Tramadol, desmethyltramadol, N-desmethyltramadol, O,N-didesmethyltramadol, Inosine, hypoxanthine, Amprenavir, Atazanavir, Acetaminophen, Lamotrigine, Aromatic amines, Dansyl amino, arylalkanoic acids, propylgallate, butylhydroxyanisole, bu-tylhydroxytoluene, oxytetracycline, chlortetracycline, tetraethoxysilane, TEOS, N-(b-aminoethyl)-c-aminopropylmethyldimethoxysilane, AEAPMDMS

High Order Textural Classification of Two SAR ERS Images on Mount Cameroon

Many researchers have demonstrated that textural data increase the precision of a classification when they are combined with level of grey information. However, the calculation of textural parameters of order two is often too long in a computer. The problem is more complex when one must compute higher order textural parameters, which however can considerably improve the precision of a classification. This work is based on statistical methods of order two and three for the calculation of textural parameters [Akono et al., 2003]. In this work, we suggest a new method of calculation of textural parameters, which is more general, not limiting itself only on order two or three, but which goes until an order n > 2, but still remaining applicable to orders two and three. The principle of this study consists in reducing the calculation of a n‐summation of type () generally utilized in the evaluation of textural parameters, to a simple summation of type . ψ is a function depending on the matrix frequency (co‐occurrence matrix in the case of order two parameters) of the n‐uplets of levels of grey in an image window. After this transformation, a considerable gain in time and memory space of the computer has been obtained. This method produces exactly the same result as the classical method, but with a spatial and a temporal gain growing with the order of the textural parameter. This method has been developed and tested successively at orders two, three, four and five with two synthetic aperture radar (SAR) images of satellites ERS‐1 and ERS‐2, of size 986 × 1390 pixels, on a computer with a random access memory (RAM) of 352 megabyte and a Pentium processor of 2,4 gigahertz of speed. The obtained results show that, for the evaluation of the “summation” textural parameter of order two, considering an image window of size 7 × 7, the new calculation method is ten times faster than the classical method of computing co‐occurrence matrix of levels of grey. At order three, the new method is nineteen times faster and at order four, it is a twelve thousands times faster. The developed methodology has allowed making a comparative classification study of the ground's occupation on the volcanic area of mount Cameroon, between the years 1998 and 2003. In fact the “summation” textural parameter at orders two, three, four and five has been applied on the two SAR images of the study region. The comparison of the ground occupation areas on the study site has been done from a non supervised classification realized on the textural image. The increasing of the area of the flows of lava due to the 1999 and 2000 eruptions has been put in evidence.

Second harmonic transthoracic echocardiography: the new reference screening method for the detection of patent foramen ovale

Transesophageal echocardiography (TEE) is still considered as the reference method for the non-invasive detection of right-to-left shunts. Echocardiographic laboratories are spending most of their time performing TEE studies to exclude a thromboembolic cardiac disease. In a considerable proportion of these patients the question can be simplified to exclude a PFO. Replacing these TEE studies by TTE would result in a considerable gain in time and money. We evaluated the value of transthoracic echocardiography with second harmonic imaging (TTE) (SH) and peripheral intravenous agitated saline solutions in the detection of patent foramen ovale (PFO) in a large cohort of patients. In 256 consecutive patients, TEE and TTE (SH) with the consecutive administration of three intravenous contrast injections of agitated saline injections before the release phase of the Valsalva manoeuvre were performed. Semi-quantification and timing of contrast passage were assessed during both imaging modalities. A shunt was present if at least one imaging modality showed microbubbles appearing in the left atrium. PFO was defined when these bubbles appeared early and arteriovenous pulmonary malformations were suspected if bubbles appeared late after the opacification of the right atrium. Shunts were considered important when >20 bubbles were present in one frame in the left atrium or left ventricle. From the 256 patients, 60 presented a passage of contrast from the right to the left atrium in at least one imaging modality. PFO was detected by TEE in 53 patients and by TTE in 55 patients (sensitivity: 90.5% and specificity: 96.5% if TEE is accepted as the golden standard) (p>0.05). Considering only the important shunts TEE detected 39 important shunts and TTE 46 important shunts (sensitivity: 89.7% and specificity: 94.6%) (p>0.05). AV pulmonary malformations were detected by TEE in 7 patients and by TTE in 10 patients (sensitivity: 85.7% and specificity: 98.3%) (p>0.05). In this large cohort of patients TTE (SH) is as accurate as TEE for the detection of PFO and late right-to-left shunts. If the only purpose of TEE is the detection of PFO such as in young cryptogenic stroke patients and in divers, TEE can be replaced by TTE (SH).

Laparoscope-Assisted Appendectomy in Children: The Two-Trocar Technique

The conventional cannulae position in laparoscopic appendectomy does not permit good visualization of the appendix, especially if it is in a retrocaecal or pelvic position. In children, the smaller dimension of the peritoneal cavity aggravates this problem. In order to optimize appendix visualization, we propose a modification of the cannulae position associated with extraabdominal appendectomy. Two trocars are inserted, one in the umbilicus under direct vision and one in the midline above the pubic symphysis. The telescope is inserted in the second cannula. The appendix is delivered via the umbilical trocar incision and a conventional appendectomy is performed. During a one-year period, 38 appendectomies were performed. In 29 cases (76.3 %) the technique was successful. In 9 patients (4 with peritonitis, 4 with a retrocaecal and one with a pelvic appendix) a third trocar was necessary to complete the operation. We had two conversions (5.2 %), one to open surgery and one to intraabdominal laparoscopic appendectomy. Mean operation time was 19 min. There were two infectious complications (one parietal and one intraabdominal). The excellent visualization permitted considerable time gain. Infectious complications were also low. This method is suggested as an alternative procedure for appendectomy, especially in children, because of their favorable anatomy.

A single-step purification of bothropstoxin-1.

Bothrops venoms are complex mixtures of components with a wide range of biological activities. Among these substances, myotoxins have been investigated by several groups. Bothropstoxin-1 (Bthtx-1) is a phospholipase A2-like basic myotoxin from Bothrops jararacussu. The purification of this component involves two chromatographic steps. Although providing a pure material, the association of these two steps is time consuming and a single-step method using high performance chromatography media would be useful. In the present study, we describe a single-step purification method for Bthtx-1. Bothrops jararacussu venom was dissolved in 1 ml buffer. After centrifugation, the supernatant was injected into a Resource-S cation exchange column connected to an FPLC system and eluted with a linear salt gradient. The complete procedure took 20 min, representing a considerable time gain when compared to a previously described method (Homsi-Brandenburgo MI et al. (1988) Toxicon, 26: 615-627). Bthtx-1 purity and identity, assessed by SDS-PAGE and N-terminal sequencing, resulted in a single band with a molecular mass of about 14 kDa and the expected sequence of the first 5 residues, S-L-F-E-L. Although the amount of protein purified after each run is lower than in the previously described method, we believe that this method may be useful for small-scale purifications.

Evaluation of the automation of immunoenzymatic procedures in a routine histo/cytopathological laboratory.

Eighteen months experience in the use of an automated staining machine for lengthy histological and immunohistochemical stains in a routine pathology laboratory is described. The apparatus yields an important saving in time for technicians and can maintain the quality of staining at a standardized high level. A disadvantage is the larger volumes of reagents required. Introduction of the machine is recommended when at least five different but lengthy stains have to be performed each day. The considerable gain in time for the technicians has important consequences for the management of pathological laboratories in the near future.

Optimization of thin layer chromatography for toxicological screening: applicability of shorter development distances.

Over the years, numerous TLC systems have been developed, each of them having their special advantages. Yet little or no attention has been paid to the time-factor needed to obtain sufficiently reliable Rf-values, combined with satisfactory resolution. As speed remains an important factor in toxicology, the applicability of shorter development distances have been investigated, resulting in a considerable gain in time as the development times increase exponentially with developing distance. In this paper, the effects of shorter development distances on resolution, spot size, reproducibility of Rf-values, and sensitivity of detection are described.

Computation of finite strains from moire displacement patterns

A new and accurate method is described for deriving finite strains from moiré displacement patterns. The components u and v of the displacements at the mesh points of a Lagrangian co-ordinate network are estimated from the moiré fringes. In the neighbourhood of a point, where the strains are to be calculated, two algebraic functions are determined, approximating as closely as possible to the two sets of estimated u and v values. The strains are then calculated from the partial derivatives of these two functions. The procedure is repeated for all points at which the strains are required. When this procedure is applied to a great number of points the use of a computer becomes a practical necessity. Once the formulae have been programmed, the operator has only to estimate the u and v values at the mesh points of the co-ordinate network and to feed this set of numbers to the computer. This new method thus allows a considerable gain in time and brings about an improvement in accuracy compared with other methods.