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The smart factory leads to a strong digitalization of industrial processes and continuous communication between the systems integrated into the production, storage, and supply chains. One of the research areas in Industry 4.0 is the possibility of using autonomous and/or intelligent industrial vehicles. The optimization of the management of the tasks allocated to these vehicles with adaptive behaviours, as well as the increase in vehicle-to-everything communications (V2X) make it possible to develop collective and adaptive intelligence for these vehicles, often grouped in fleets. Task allocation and scheduling are often managed centrally. The requirements for flexibility, robustness, and scalability lead to the consideration of decentralized mechanisms to react to unexpected situations. However, before being definitively adopted, decentralization must first be modelled and then simulated. Thus, we use a multi-agent simulation to test the proposed dynamic task (re)allocation process. A set of problematic situations for the circulation of autonomous industrial vehicles in areas such as smart warehouses (obstacles, breakdowns, etc.) has been identified. These problematic situations could disrupt or harm the successful completion of the process of dynamic (re)allocation of tasks. We have therefore defined scenarios involving them in order to demonstrate through simulation that the process remains reliable. The simulation of new problematic situations also allows us to extend the potential of this process, which we discuss at the end of the article. [ABSTRACT FROM AUTHOR]

Industry 4.0 leads to a strong digitalization of industrial processes, but also a significant increase in communication and cooperation between the machines that make it up. This is the case with autonomous industrial vehicles (AIVs) and other cooperative mobile robots which are multiplying in factories, often in the form of fleets of vehicles, and whose intelligence and autonomy are increasing. While the autonomy of autonomous vehicles has been well characterized in the field of road and road transport, this is not the case for the autonomous vehicles used in industry. The establishment and deployment of AIV fleets raises several challenges, all of which depend on the actual level of autonomy of the AIVs: acceptance by employees, vehicle location, traffic fluidity, collision detection, or vehicle perception of changing environments. Thus, simulation serves to account for the constraints and requirements formulated by the manufacturers and future users of AIVs. In this paper, after having proposed a broad state of the art on the problems to be solved in order to simulate AIVs before proceeding to experiments in real conditions, we present a method to estimate positions of AIVs moving in a closed industrial environment, the extension of a collision detection algorithm to deal with the obstacle avoidance issue, and the development of an agent-based simulation platform for simulating these two methods and algorithms. The resulting/final/subsequent simulation will allow us to experiment in real conditions. [ABSTRACT FROM AUTHOR]

High-density surface electromyography (HD-sEMG) is a recent technique that overcomes the limitations of monopolar and bipolar sEMG recordings and enables the collection of physiological and topographical informations concerning muscle activation. However, HD-sEMG channels are usually contaminated by noise in an heterogeneous manner. The sources of noise are mainly power line interference (PLI), white Gaussian noise (WGN) and motion artifacts (MA). The spectral components of these disruptive signals overlap with the sEMG spectrum which makes classical filtering techniques non effective, especially during low contraction level recordings. In this study, we propose to denoise HD-sEMG recordings at 20 % of the maximum voluntary contraction by using a second-order blind source separation technique, named canonical component analysis (CCA). For this purpose, a specific and automatic canonical component selection, using noise ratio thresholding, and a channel selection procedure for the selective version (sCCA) are proposed. Results obtained from the application of the proposed methods (CCA and sCCA) on realistic simulated data demonstrated the ability of the proposed approach to retrieve the original HD-sEMG signals, by suppressing the PLI and WGN components, with high accuracy (for five different simulated noise dispersions using the same anatomy). Afterward, the proposed algorithms are employed to denoise experimental HD-sEMG signals from five healthy subjects during biceps brachii contractions following an isometric protocol. Obtained results showed that PLI and WGN components could be successfully removed, which enhances considerably the SNR of the channels with low SNR and thereby increases the mean SNR value among the grid. Moreover, the MA component is often isolated on specific estimated sources but requires additional signal processing for a total removal. In addition, comparative study with independent component analysis, CCA-wavelet and CCA-empirical mode decomposition (EMD) proved a higher efficiency of the presented method over existing denoising techniques and demonstrated pointless a second filtering stage for denoising HD-sEMG recordings at this contraction level. [ABSTRACT FROM AUTHOR]

Abstract: Aim: The effects of dehydration on muscle performance in human are still contradictory, notably regarding muscle force. The effect of water deprivation (WD) on mechanical properties of skeletal muscle, and more precisely its impact on slow and fast muscles, remains largely unknown. The aim of this study was to determine for the first time whether WD leads to changes in contractile properties of skeletal muscle and whether these changes were muscle‐type‐specific. Methods: Sixteen‐week‐old male rats were assigned to either a control group (C) with water or a 96‐hour WD group. At the end of the period, twitch and tetanus properties, as well as biochemical and structural analysis, were performed on soleus (SOL) and extensor digitorum longus (EDL) muscles. Results: Absolute twitch (Pt) and tetanic (P0) tension were, respectively, 17% and 14% lower in EDL of WD rats as compared with C rats, whereas unexpected increases of 43% and 25% were observed in SOL. Tensions normalized with respect to muscle mass were not affected by WD in EDL, whereas they were increased by more than 40% in SOL. A 96‐hour WD period leads to a decrease in fibre cross‐sectional area and absolute myofibrillar content only in EDL. Conclusion: It is hypothesized that differences in the results between slow and fast muscles may come from (i) a muscle‐type‐specific effect of WD on protein balance, EDL showing a greater myofibrillar protein breakdown and (ii) a greater sensitivity to osmolality changes induced by WD in EDL than in SOL. [ABSTRACT FROM AUTHOR]

To obtain a better understanding of the adaptations of human tendon to chronic overloading, we examined the relationships between these adaptations and the changes in muscle structure and function. Fifteen healthy male subjects (20 ± 2 yr) underwent 9 wk of knee extension resistance training. Patellar tendon stiffness and modulus were assessed with ultrasonography, and cross-sectional area (CSA) was determined along the entire length of the tendon by using magnetic resonance imaging. In the quadriceps muscles, architecture and volume measurements were combined to obtain physiological CSA (PCSA), and maximal isometric force was recorded. Following training, muscle force and PCSA increased by 31% (P < 0.0001) and 7% (P < 0.01), respectively. Tendon CSA increased regionally at 20- 30%, 60%, and 90-100% of tendon length (5-6%; P < 0.05), and tendon stiffness and modulus increased by 24% (P < 0.001) and 20% (P < 0.01), respectively. Although none of the tendon adaptations were related to strength gains, we observed a positive correlation between the increase in quadriceps PCSA and the increases in tendon stiffness (r = 0.68; P < 0.01) and modulus (r = 0.75; P < 0.01). Unexpectedly, the increase in muscle PCSA was inversely related to the distal and the mean increases in tendon CSA (in both cases, r = -0.64; P < 0.05). These data suggest that, following short-term resistance training, changes in tendon mechanical and material properties are more closely related to the overall loading history and that tendon hypertrophy is driven by other mechanisms than those eliciting tendon stiffening. [ABSTRACT FROM AUTHOR]

BACKGROUND: Tuberculosis of the central nervous system (CNS) is a serious, often fatal disease primarily affecting young children. It develops after hematogenous dissemination and subsequent invasion of the CNS by Mycobacterium tuberculosis. The microbial determinants involved in CNS disease are poorly characterized. METHODS: Hematogenously disseminated M. tuberculosis infection was simulated in BALB/c mice by intravenous challenge. Bacteria were recovered using standard culture techniques. Host immune response to M. tuberculosis infection was assessed by histopathological and cytokine profile analysis. By means of a pooled infection with genotypically defined M. tuberculosis mutants, bacterial genes required for invasion or survival were determined in the CNS and lung tissue. RESULTS: M. tuberculosis were detected in whole mouse brains as early as 1 day after intravenous infection and at all time points assessed thereafter. No significant immune response was elicited in the infected brain tissue, compared with extensive inflammation in the infected lung tissue at the same time point. We identified mutants for 5 M. tuberculosis genes (Rv0311, Rv0805, Rv0931c, Rv0986, and MT3280) with CNS-specific phenotypes, absent in lung tissue. CONCLUSIONS: We have identified CNS-specific M. tuberculosis genes involved in the pathogenesis of tuberculosis. Further characterization of these genes will help in understanding the microbial pathogenesis of CNS tuberculosis. Copyright © 2008 Infectious Diseases Society of America [ABSTRACT FROM AUTHOR]

Haematopoietic stem cell transplantation is often complicated by the life-threatening graft- versus-host disease (GVHD) which consists of an allogeneic reaction of the graft cells against the host organs. The aim of this study was to investigate the putative involvement of soluble human leucocyte antigen (sHLA) class I molecules, and particularly sHLA-G molecules, in the occurrence and/or prevention of acute GVHD (aGVHD) in allogeneic peripheral blood stem cell (PSC) transplantation. Whole sHLA class I molecules seem to be involved in aGVHD pathogenesis because detection of a high concentration of these molecules in the first month post allograft is correlated with aGVHD occurrence. Conversely, a high level of sHLA-G molecules before and after allograft could indicate good prognosis in PSC allograft transplantation. sHLA-G molecules seem to be involved in aGVHD prevention, not only because they are enriched in plasma of patients without aGVHD, but also because: (i) a positive correlation has been found between sHLA-G level and CD4+ CD25+ CD152+ natural regulatory T cell (Treg) frequency in the blood of transplanted patients; and (ii) the presence of CD4+ CD25+ CD152+ natural Treg is correlated with increased sHLA-G expression in in vitro mixed leucocyte reaction cultures. Altogether, these results support the immunomodulatory function of sHLA-G molecules that might create a regulatory network together with the natural Treg to foster the induction of a tolerogenic environment and improve PSC transplantation favourable outcome. [ABSTRACT FROM AUTHOR]

The therapy of mycobacterial infections is challenging for a number of reasons. Because mycobacteria are not susceptible to many classes of antibacterial agents, treatment typically requires the use of antimicrobial drugs that are not commonly used and may have small therapeutic windows. For many species, procedures for drug susceptibility testing and optimal treatment regimens have yet to be defined. Finally, because mycobacteria are generally slow to succumb to antimicrobial agents, therapy must be given with multiple drugs for prolonged periods of time, making it necessary to monitor for drug toxicity, drug interactions, and patient nonadherence. Better understanding of the pharmacokinetics and pharmacodynamics of antimycobacterial agents should improve the therapy of mycobacterial infections. Using current treatment strategies for tuberculosis and Mycobacterium avium complex infections as examples, this review highlights basic pharmacokinetic and pharmacodynamic principles and the rationale for combination chemotherapy that should also be applicable to other mycobacterial infections. [ABSTRACT FROM AUTHOR]

Summary. Multidrug resistance protein (MRP) activity was investigated in 44 newly diagnosed acute myeloid leukaemia (AML) patients using a functional assay based on efflux of carboxy-2′,7′-dichlorofluorescein, an anionic dye handled by both MRP1 and MRP2. Elevated MRP transport was detected in 29% of cases, but was not significantly correlated with sex, age, white blood cell count at diagnosis or karyotype. In contrast, it was associated with secondary AML (P = 0·002), CD34 positivity (P = 0·041) and P-glycoprotein activity (P = 0·01). There was a lower rate of complete remission in MRP-positive patients versus MRP-negative patients (23% versus 81%; P = 0·001); overall survival was also better for MRP-negative patients (P = 0·004). These data indicate a probable role for MRP activity in the clinical outcome of AML. [ABSTRACT FROM AUTHOR]

The Mycobacterial Growth Indicator Tube, a reliable system for detection of mycobacterial growth, was compared with the reference proportion method on Löwenstein-Jensen medium for antibiotic susceptibility testing of Mycobacterium tuberculosis. A total of 62 clinical strains and four reference strains of Mycobacterium tuberculosis were tested for susceptibility to streptomycin, isoniazid, rifampicin and ethambutol. Of these, 36 were susceptible to all four antibiotics and 30 were resistant to at least one of them. Tests were repeated in cases of discrepant results. When each drug/strain combination was considered separately, the overall agreement between the two methods was 96.5% (98.4% for streptomycin, 95.3% for isoniazid, 96.9% for rifampicin and 95.3% for ethambutol) with regard to the initial testing and 98.8% (100, 98.5, 98.5 and 98.4%, respectively) after repeated testing. When the results were considered strain by strain, the agreement was 86% after the initial testing and 95% after repeated testing. The results were obtained after a mean time of 9.5 days. These results suggest that the Mycobacterial Growth Indicator Tube is a reliable method for testing susceptibility of mycobacterial strains to first-line antituberculous drugs. [ABSTRACT FROM AUTHOR]

Three strains of mice (Swiss albinos, C57BL/6,C3H/OuJ) were injected intravenously with 3.7 x 106 colony forming units (CFU) of M. tuberculosis. H37RV, sensitive and resistant to antibiotics (90% of bacilli sensitive, 9% resistant lo Streptomycin and 0.9% resistant to Kanamycin). Two weeks later, chemotherapy was started 6 days a week for a 6-month period with isoniazid (INH) and rifampicin (RMP). Twenty mice of each strain were killed at the end of the chemotherapy and the others were kept without antibiotics for a second 6-month follow-up period before being killed. The early multiplication of bacilli during the first 2 weeks following infection and before chemotherapy, was similar in the three strains of mice. Chemotherapy had the same apparent efficacy in the three strains of mice, nearly all the mice being cured as assessed by a negative spleen culture on Lowenstein-Jensen medium at the end of chemotherapy. But after the 6-month follow-up period, the C3H strain presented a statistically significantly higher level of positive spleen culture ('relapse') than seen in the C57BL/6 strain, and an increased number of mycobacteria per relapsing mouse spleen. It has been estimated with the help of resistant and sensitive bacilli that the relapses were due in most of the cases to the regrowth of one or very few bacilli. giving a clone. It seems that the C3H strain of mice, known to carry the Bcg-r allele of the Beg gene, might be less able to develop a specific acquired resistance capable of stopping the delayed development of a highly virulent strain of mycobacteria. [ABSTRACT FROM AUTHOR]

Two dosages of clarithromycin were compared for treatment of disseminated Mycobacterium avium disease of AIDS patients: high-dose (HD): 1,000 mg or 750 mg b.i.d. according to body weight, and low-dose (LD): 1,000 mg or 750 mg q.d. Patients with high probability of M. avium positive blood culture on day 0 received a 42-day clarithromycin treatment with HD (n=27) or LD (n=28) at random after stratification according to body weight. Assessment procedures, including quantitative blood cultures, were performed at days 14, 28 and 42. Forty-five patients were eligible for clinical and 28 for bacteriological evaluation. Bacteriological success was observed in 12 HD and 11 LD patients, partial success in one HD and two LD and failure in none of the HD and two LD (p=0.33). Between days 0 and 42, log decreases in CFU counts/ml were (mean ± SD) 3.13±0.82 (HD) and 2.67±1.8 (LD) (p=0.38). Fever and night sweats significantly improved similarly in both groups; no change in spleen and liver size was observed on CT scans. Eight patients died during the study but no death was reported as drug related. Sixteen patients (HD=6, LD=10) discontinued the treatment because of side effects. A trend towards improved bacteriological effectiveness and reduced tolerance was observed in the HD group but the difference was not significant. With a power of 0.70, no dose effect was demonstrated between the two tested dosages. A daily dose of 1,000 mg clarithromycin was tested in drug combinations to treat disseminated M. avium infection in AIDS patients. [ABSTRACT FROM AUTHOR]

Clarithromycin has been reported to select clarithromycin resistant mutants of Mycobacterium avium complex (MAC) during treatment with clarithromycin in AIDS patients and beige mice. We selected resistant mutants in vitro at a frequency of 5 x 10(-9). Clarithromycin resistant strains of MAC isolated in AIDS patients and beige mice as well as derivatives selected in vitro had a unique pattern of acquired cross-resistance to macrolides and related antibiotics. In contrast, the pattern of resistance to non-macrolide antibiotics remained unchanged in clarithromycin resistant strains. A dramatic decrease in ribosome affinity for clarithromycin and erythromycin was found in clarithromycin resistant strains, but no mutation was found in the peptidyl domain of the 23S rRNA, indicating that another ribosomal modification is involved. [ABSTRACT FROM AUTHOR]

The in-vitro activity of FCE 22101 was compared with those of imipenem, aztreonam, cefotaxime, ceftriaxone and latamoxef against 225 Enterobacteriaceae (209 clinical isolates and 16 derivatives of Escherichia coli K12) chosen for their resistance (MIC greater than or equal to 8 mg/l) to third-generation cephalosporins. The beta-lactamases produced by the strains of Enterobacter cloacae, Klebsiella pneumoniae and Esch. coli were identified. The mean MICs of FCE 22101 were 2-8 mg/l for Ent. cloacae, Citrobacter freundii and Morganella morganii. For Ent. cloacae, the MICs were slightly higher for the cephalosporinase non overproducing (5.5-8 mg/l) than for the cephalosporinase overproducing (4.5 mg/l) strains. The mean MIC was 9 mg/l for Serratia spp. but for half of the strains the MICs were greater than or equal to 16 mg/l. The MICs of FCE 22101 were 0.5-1 mg/l for the resistant clinical isolates or isogenic derivatives of K. pneumoniae and Esch. coli producing extended broad-spectrum beta-lactamases (SHV-2, SHV-3 or CTX-1), whether measured in the presence of clavulanate or not, and against the sensitive controls. This showed that the compound was not affected by these new beta-lactamases. The MICs of imipenem, on the average four to five times lower than those of FCE 22101, were found to be very similar for resistant and sensitive strains. The MICs of aztreonam were high (32-128 mg/l) for C. freundii, K. oxytoca and cephalosporinase overproducing strains of Ent. cloacae. There was cross-resistance between the third-generation cephalosporins, but the MICs of latamoxef remained low (1 mg/l) against M. morganii, Klebsiella spp. and Esch. coli. [ABSTRACT FROM AUTHOR]

The in-vitro activity of FCE 22101 was compared with those of imipenem, aztreonam, cefotaxime, ceftriaxone and latamoxef against 223 Enterobacteriaceae (209 clinical isolates and 16 derivatives of K12) chosen for their resistance (MIC ≥ 8 mg/l) to third-generation cephalosporins. The -lactamases produced by the strains of and were identified. The mean MICs of FCE 22101 were 2–8 mg/l for , and . For , the MICs were slightly higher for the cephalosporinase non overproducing (5·5–8 mg/l) than for the cephalosporinase overproducing (4·5 mg/l) strains. The mean MIC was 9 mg/l for spp. but for half of the strains the MICs were ≥ 16 mg/l. The MICs of FCE 22101 were 0·5–1 mg/l for the resistant clinical isolates or isogenic derivatives of and producing extended broad-spectrum -lactamases (SHV-2, SHV-3 or CTX-1), whether measured in the presence of clavulanate or not, and against the sensitive controls. This showed that the compound was not affected by these new -lactamases. The MICs of imipenem, on the average four to five times lower than those of FCE 22101, were found to be very similar for resistant and sensitive strains. The MICs of aztreonam were high (32–128 mg/l) for , and cephalosporinase overproducing strains of . There was cross-resistance between the third-generation cephalosporins, but the MICs of latamoxef remained low (1 mg/l) against , spp. and . [ABSTRACT FROM PUBLISHER]

The phenotypes of susceptibility to ampicillin, carbenicillin, cephalothin, cefamandole, cefoxitin and cefotaxime were determined by the disc-diffusion method in 10,994 Enterobacteriaceae consecutively isolated from in-patients during 18 months. The susceptible phenotypes were much more frequent among Escherichia coli, Proteus mirabilis and Klebsiella (67.4 to 84.8%) than among Serratia, Enterobacter and Citrobacter (8.8 to 35.5%). In all species the most common resistance phenotypes were to ampicillin and carbenicillin: E. coli (28%), Pr. mirabilis (15.2%), Klebsiella (23.8%), indole-positive Proteus (33.3%), Serratia (74.4%), Enterobacter (61.4%) and Citrobacter (74.8%). Among E. coli 4.6% of the strains were resistant to ampicillin and cephalothin but susceptible to carbenicillin. Among E. coli, Pr. mirabilis and Klebsiella the strains susceptible only to cefotaxime represented 0.3 to 5% and no cefotaximeresistant strain was isolated; whereas among Serratia, Enterobacter and Citrobacter the former represented 28.3 to 58.3% and the latter 7.5 to 18.5%. Some important differences in the distribution of the phenotypes according to the type of ward were observed. [ABSTRACT FROM PUBLISHER]

Thirty-six patients with newly diagnosed lepromatous leprosy were allocated randomly to three groups and treated for 56 days with minocycline (100 mg daily), clarithromycin (500 mg daily), or clarithromycin (500 mg) plus minocycline (100 mg daily). All groups had rapid and remarkable clinical improvement and significant decline of the bacterial and morphologic indices in skin smears during treatment. More than 99% and > 99.9% of the viable Mycobacterium leprae had been killed by 28 and 56 days of treatment, respectively, as measured by inoculation of organisms recovered from skin samples, taken before and during treatment, into the footpads of immunocompetent and nude mice. Clinical improvement and bactericidal activity did not differ significantly among the three groups. Adverse reactions were rare and mild, and no laboratory abnormality was detected during the trial. Both clarithromycin and minocycline displayed powerful bactericidal activities against M. leprae in leprosy patients and may be considered important components of new multidrug regimens for the treatment of multibacillary leprosy. [ABSTRACT FROM AUTHOR]

The article investigates H-reflex changes but the reflexes were analyzed on the three parts of the triceps surae to compare the eventual changes after an endurance training period for a slow (soleus) or a faster (gastrocnemius) muscle. The experiment on endurance training involving students who are sedentary and with recreationally physical activity is described. It was found that reflex changes were more pronounced in muscles with a lower content in fibers adapted to this type of exercise.

The article examines correlated changes in reflex amplitude and stiffness parameters in prepubertal children. The method for measuring the stretch reflex of the triceps surae in prepubertal children is described. At rest and during voluntary contractions, the reflexes mechanically induced on the triceps surae increase with the age of the prepubertal children. The increase seems likely to depend on the stiffness of the elastic structures linked to the muscle receptors to stretch.