Articles de revues : « LdtF »

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Bahadur, Raj, Pavan Kumar Chodisetti et Manjula Reddy. « Cleavage of Braun’s lipoprotein Lpp from the bacterial peptidoglycan by a paralog of l,d-transpeptidases, LdtF ». Proceedings of the National Academy of Sciences 118, n^o 19 (3 mai 2021) : e2101989118. http://dx.doi.org/10.1073/pnas.2101989118.

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The gram‐negative bacterial cell envelope is made up of an outer membrane (OM), an inner membrane (IM) that surrounds the cytoplasm, and a periplasmic space between the two membranes containing peptidoglycan (PG or murein). PG is an elastic polymer that forms a mesh-like sacculus around the IM, protecting cells from turgor and environmental stress conditions. In several bacteria, including Escherichia coli, the OM is tethered to PG by an abundant OM lipoprotein, Lpp (or Braun’s lipoprotein), that functions to maintain the structural and functional integrity of the cell envelope. Since its discovery, Lpp has been studied extensively, and although l,d-transpeptidases, the enzymes that catalyze the formation of PG−Lpp linkages, have been earlier identified, it is not known how these linkages are modulated. Here, using genetic and biochemical approaches, we show that LdtF (formerly yafK), a newly identified paralog of l,d-transpeptidases in E. coli, is a murein hydrolytic enzyme that catalyzes cleavage of Lpp from the PG sacculus. LdtF also exhibits glycine-specific carboxypeptidase activity on muropeptides containing a terminal glycine residue. LdtF was earlier presumed to be an l,d-transpeptidase; however, our results show that it is indeed an l,d-endopeptidase that hydrolyzes the products generated by the l,d-transpeptidases. To summarize, this study describes the discovery of a murein endopeptidase with a hitherto unknown catalytic specificity that removes the PG−Lpp cross-links, suggesting a role for LdtF in the regulation of PG–OM linkages to maintain the structural integrity of the bacterial cell envelope.

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Coleman, Steven M. « PAGES Lake Drilling Task Force (LDTF) ». PAGES news 7, n^o 1 (mars 1999) : 13–14. http://dx.doi.org/10.22498/pages.7.1.13.

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Casadei, F., C. Delzano, G. Magonette, J. P. Halleux et G. Verzeletti. « Dynamic testing of large AISI-316L steel specimens behaviour using LDTF ». Nuclear Engineering and Design 102, n^o 3 (juillet 1987) : 463–74. http://dx.doi.org/10.1016/0029-5493(87)90191-9.

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Jones, P. M., F. Casadei et J. P. Halleux. « Progress in numerical modelling of dynamic specimen behaviour in the LDTF ». Nuclear Engineering and Design 112 (mars 1989) : 51–64. http://dx.doi.org/10.1016/0029-5493(89)90145-3.

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Delzano, C., E. Gutierrez, P. M. Jones et G. Verzeletti. « Recent developments and results of LDTF tests on steel and concrete specimens ». Nuclear Engineering and Design 112 (mars 1989) : 65–80. http://dx.doi.org/10.1016/0029-5493(89)90146-5.

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Garnsworthy, P. C. « The interaction between dietary fibre level and protein degradability in dairy cows ». Animal Science 48, n^o 2 (avril 1989) : 271–81. http://dx.doi.org/10.1017/s0003356100040277.

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ABSTRACTA trial was performed to investigate the interaction between energy and protein source for cows in negative energy balance. Six cows were assigned to each of four types of concentrate (metabolizable energy (ME) 12 MJ/kg dry matter (DM), crude protein (CP) 180 g/kg DM) with low or high fibre contents (LF or HF) and protein degradability (LD or HD). For groups HDLF, LDLF, HDHF and LDHF respectively, acid-detergent fibre contents (g/kg diet DM) were 69·2, 66·1, 117·5 and 113·3; protein degradability values were determined as 0·78, 0·61, 0·72 and 0·66. Low-fibre diets were given at the rate of 11 kg/day concentrates with 6 kg/day hay (ME 8 MJ/kg DM, CP 84·5 g/kg DM) and high-fibre diets at the rate of 10 kg/day concentrates with 7·5 kg/day hay from weeks 4 to 13 of lactation. Cows were given a standard diet over the first 3 weeks of lactation and performance in week 3 was used as a covariate.Milk yield was not affected by treatment but the butterfat content of milk from cows given the high-fibre diets (44·9 g/kg) was higher than the low-fibre diets (36·4 g/kg; P < 0·01), which resulted in significant differences in fat-corrected milk yield (HDHF: 25·1, LDHF: 26·2, HDLF: 22·7, LDLF: 21·5, s.e.d. 1·5 kg/day). ME balance was lower for the LDHF group (−4·1 MJ/day) than for groups LDLF and HDLF (-15·4 and -16·8 MJ/day; P < 0·05) but was not significantly different from the HDHF group (-29·4 MJ/day). Undegradable protein (UDP) balances were 53·4, 93·8, -21·2 and 193·8 (s.e.d. 45, P < 005) g/day for groups HDLF, LDLF, HDHF and LDHF respectively. Differences from zero in ME and UDP balance were accounted for in all groups except LDHF by changes in live weight plus a systematic correction of approximately 10 MJ/day. It is considered that the cows given high-fibre diets responded to high UDP by increasing fat-corrected milk production but mobilization of body fat to support this increase was accompanied by retention of protein with associated water, resulting in very little change in live weight. It is also probable that the high UDP levels improved the digestion of fibre i n the rumen, but this is unlikely to have been sufficient to have accounted for all of the response.

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Shi, Nan, Shuangya Wen, Qianwen Gao, Zhiqiang Gao et Huibing Yang. « Printed Sowing of High-Density Mechanical Transplanted Hybrid Rice Can Reduce the Amount of Fertilizer Needed ». Agronomy 12, n^o 9 (25 août 2022) : 2002. http://dx.doi.org/10.3390/agronomy12092002.

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In this study, we investigated how printed sowing machine transplanting impacts the yield of single-season rice by increasing the planting density and decreasing the amount of fertilizer needed. The study was aimed at exploring the relationships between the amount of fertilizer, transplanting density, and rice yield. During the rice growing season from 2019 to 2020 in the middle and lower reaches of the Yangtze River, six different field trials were conducted: low density and high fertilizer (LDHF), low density and low fertilizer (LDLF), middle density and high fertilizer (MDHF), middle density and low fertilizer (MDLF), high density and high fertilizer (HDHF), and high density and low fertilizer (HDLF). It turns out that compared to the LDHF, the thousand seed weight, the spikelets per panicle, the seed-setting rate, and the SPAD value at the filling stage decreased by 0.17% and 0.60%, 5.36% and 10.59%, 5.70% and 4.66%, and 17.52% and 4.93% in 2019 and 2020, respectively. However, compared to the LDHF, the panicles increased by 15.31% and 17.18%, respectively, the LAI at the filling stage increased by 1.92% and 0.48%, respectively, and the accumulation of dry matter above ground at the maturity stage also increased by 3.74% and 16.79% in 2019 and 2020, respectively. Therefore, compared to the yield of rice in the LDHF, the yield of rice in the HDLF increased by 5.06% and 6.64%. The yields of rice in the LDLF, MDHF, MDLF, and HDHF were lower than that in the LDHF and HDLF. The partial least squares path model (PLSPM) analysis showed that the fertilizer, density, and aboveground dry matter had positive effects on the yield, while the SPAD value and LAI had negative effects on the yield. This research shows that increasing the transplanting density can compensate for the yield loss caused by reducing the fertilizer amount. However, no combination of the transplanting density and fertilization amount can achieve the purpose of increasing the yield.

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Sanders, Akeisha N., Lori F. Wright et Martin S. Pavelka. « Genetic characterization of mycobacterial l,d-transpeptidases ». Microbiology 160, n^o 8 (1 août 2014) : 1795–806. http://dx.doi.org/10.1099/mic.0.078980-0.

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l,d-Transpeptidases (Ldts) catalyse the formation of 3–3 cross-links in peptidoglycans (PGs); however, the role of these enzymes in cell envelope physiology is not well understood. Mycobacterial PG contains a higher percentage of 3–3 cross-links (~30–80 %) than the PG in most other bacteria, suggesting that they are particularly important to mycobacterial cell wall biology. The genomes of Mycobacterium tuberculosis and Mycobacterium smegmatis encode multiple Ldt genes, but it is not clear if they are redundant. We compared the sequences of the Ldt proteins from 18 mycobacterial genomes and found that they can be grouped into six classes. We then constructed M. smegmatis strains lacking single or multiple Ldt genes to determine the physiological consequence of the loss of these enzymes. We report that of the single mutants, only one, ΔldtC (MSMEG_0929, class 5), displayed an increased susceptibility to imipenem – a carbapenem antibiotic that inhibits the Ldt enzymes. The invariant cysteine in the active site of LdtC was required for function, consistent with its role as an Ldt. A triple mutant missing ldtC and both of the class 2 genes displayed hypersusceptibility to antibiotics, lysozyme and d-methionine, and had an altered cellular morphology. These data demonstrated that the distinct classes of mycobacterial Ldts may reflect different, non-redundant functions and that the class 5 Ldt was peculiar in that its loss, alone and with the class 2 proteins, had the most profound effect on phenotype.

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Hernández, Sara B., Sónia Castanheira, M. Graciela Pucciarelli, Juan J. Cestero, Gadea Rico-Pérez, Alberto Paradela, Juan A. Ayala et al. « Peptidoglycan editing in non-proliferating intracellular Salmonella as source of interference with immune signaling ». PLOS Pathogens 18, n^o 1 (25 janvier 2022) : e1010241. http://dx.doi.org/10.1371/journal.ppat.1010241.

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Salmonella enterica causes intracellular infections that can be limited to the intestine or spread to deeper tissues. In most cases, intracellular bacteria show moderate growth. How these bacteria face host defenses that recognize peptidoglycan, is poorly understood. Here, we report a high-resolution structural analysis of the minute amounts of peptidoglycan purified from S. enterica serovar Typhimurium (S. Typhimurium) infecting fibroblasts, a cell type in which this pathogen undergoes moderate growth and persists for days intracellularly. The peptidoglycan of these non-proliferating bacteria contains atypical crosslinked muropeptides with stem peptides trimmed at the L-alanine-D-glutamic acid-(γ) or D-glutamic acid-(γ)-meso-diaminopimelic acid motifs, both sensed by intracellular immune receptors. This peptidoglycan has a reduced glycan chain average length and ~30% increase in the L,D-crosslink, a type of bridge shared by all the atypical crosslinked muropeptides identified. The L,D-transpeptidases LdtD (YcbB) and LdtE (YnhG) are responsible for the formation of these L,D-bridges in the peptidoglycan of intracellular bacteria. We also identified in a fraction of muropeptides an unprecedented modification in the peptidoglycan of intracellular S. Typhimurium consisting of the amino alcohol alaninol replacing the terminal (fourth) D-alanine. Alaninol was still detectable in the peptidoglycan of a double mutant lacking LdtD and LdtE, thereby ruling out the contribution of these enzymes to this chemical modification. Remarkably, all multiple mutants tested lacking candidate enzymes that either trim stem peptides or form the L,D-bridges retain the capacity to modify the terminal D-alanine to alaninol and all attenuate NF-κB nuclear translocation. These data inferred a potential role of alaninol-containing muropeptides in attenuating pro-inflammatory signaling, which was confirmed with a synthetic tetrapeptide bearing such amino alcohol. We suggest that the modification of D-alanine to alaninol in the peptidoglycan of non-proliferating intracellular S. Typhimurium is an editing process exploited by this pathogen to evade immune recognition inside host cells.

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Gu, Henan, Jian Luo, Guofang Li, Yueling Yao, Yan Huang et Dongjing Huang. « Spatial-Temporal Variations of Active Accumulated Temperature and Its Impact on Vegetation NDVI in the Source Region of China’s Yellow River ». Water 14, n^o 21 (29 octobre 2022) : 3458. http://dx.doi.org/10.3390/w14213458.

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Global climate change has greatly influenced the ecosystems in the Tibetan Plateau. Many studies focused on the direct effects of climate warming on the headwater regions by mean temperature, while less investigating its implication for the eco-environment. To address this, the study discussed the spatial-temporal variations of the bio-related climate indicators ≥0 °C annual accumulated temperature AAT0 and its lasting days LDT0, and corresponding ≥5 °C indicators AAT5 and LDT5 on the source region of the Yellow River (SRYR). The stationarity of indicators during 1979–2018 were tested by Pettitt test, and trends checked by linear regression analysis and Mann-Kendall test. Normalized difference vegetation index NDVI (2001–2016) was adopted to detect the correlation between vegetation activities and indicators. Results show that the AAT and LDT0 exhibited significant increasing trend over the SRYR, while the LDT5 significantly increased mainly under 4000 m. Most LDT extended due to the combined efforts of the early onset and late termination of the given temperature. 1997 was detected in the abrupt change analysis of AAT0 both on the basin scale and most area, and was adopted to divide the period into two stages. The regional mean AAT0 linearly grew at a rate of 96 °C decade−1 during the entire period, and 104 °C decade−1 during the second stage. Except for a drastic jump in the areal mean values, there was a distinct upward-shift of isoline in elevation between stages. NDVI showed strong correlativity with ≥0 °C indicators on the basin scale, according to the Pearson, Spearman and Kendall correlation coefficients, ranging from 0.5 to 0.7. Spatially, the overlap area between Pearson’s γ ≥ 0.5 and linearly rising AAT0 reached 50%, which was fully covered with significantly increasing AAT0 during the recent stage. Thus the rapid growth of ≥0 °C indicators would effectively accelerate NDVI over this major alpine grasslands, especially around the eastern low regions, where indicators are higher and grow faster.

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Falchi, Federica A., Flaviana Di Lorenzo, Roberto Pizzoccheri, Gianluca Casino, Moira Paroni, Francesca Forti, Antonio Molinaro et Federica Briani. « Overexpression of lpxT Gene in Escherichia coli Inhibits Cell Division and Causes Envelope Defects without Changing the Overall Phosphorylation Level of Lipid A ». Microorganisms 8, n^o 6 (30 mai 2020) : 826. http://dx.doi.org/10.3390/microorganisms8060826.

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LpxT is an inner membrane protein that transfers a phosphate group from the essential lipid undecaprenyl pyrophosphate (C-55PP) to the lipid A moiety of lipopolysaccharide, generating a lipid A tris-phosphorylated species. The protein is encoded by the non-essential lpxT gene, which is conserved in distantly related Gram-negative bacteria. In this work, we investigated the phenotypic effect of lpxT ectopic expression from a plasmid in Escherichia coli. We found that lpxT induction inhibited cell division and led to the formation of elongated cells, mostly with absent or altered septa. Moreover, the cells became sensitive to detergents and to hypo-osmotic shock, indicating that they had cell envelope defects. These effects were not due to lipid A hyperphosphorylation or C-55PP sequestering, but most likely to defective lipopolysaccharide transport. Indeed, lpxT overexpression in mutants lacking the L,D-transpeptidase LdtD and LdtE, which protect cells with outer membrane defects from osmotic lysis, caused cell envelope defects. Moreover, we found that pyrophosphorylated lipid A was also produced in a lpxT deletion mutant, indicating that LpxT is not the only protein able to perform such lipid A modification in E. coli.

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Walker, R. M., et E. Zinner. « Prospects for Cosmic Dust Experiments on the Planned Reflight of LDEF ». International Astronomical Union Colloquium 85 (1985) : 127. http://dx.doi.org/10.1017/s0252921100084475.

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AbstractThe Long Duration Exposure Facility (LDEF-I), which contains a number of cosmic dust experiments, is due to be launched in the spring of 1984 and recovered about a year later. Current plans call for re-fitting the LDEF spacecraft with a large area of plastic nuclear track detectors and relaunching (LDEF-II) for a flight that will last about 2 years. The main purpose of the mission is to extend primary cosmic ray abundance measurements to the actinide region. A meeting was held at Washington University in December 1983 to discuss the problems and prospects for cosmic dust experiments on LDEF-II. Most participants were drawn from the LDEF-I community of investigators. The meeting resulted in a report which treated the scientific rationale for LDEF-II dust experiments, discussed various implementation options, and concluded with a set of summary recommendations. We discussed this report and summarized the status of LDEF-II as of this meeting. It is important to note that the report serves equally well as a basis for discussion of dust experiments on future space stations.

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Kim, Jang-il, Yireh Han, Changjin Lim, Jong-Ho Cheun, Ji Gwang Jung, Hong Kyu Kim, Han-Byoel Lee, Hyeong-Gon Moon et Wonshik Han. « Abstract P3-18-14 : Assessment of quality of life and objective cosmetic outcome of breast conserving surgery with or without latissimus dorsi mini-flap in breast cancer ». Cancer Research 82, n^o 4_Supplement (15 février 2022) : P3–18–14—P3–18–14. http://dx.doi.org/10.1158/1538-7445.sabcs21-p3-18-14.

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Abstract Introduction : Latissimus dorsi mini-flap (LDMF) with breast conserving surgery (BCS) was introduced as a useful volume replacement technique when the tumor is located in upper or outer portion of breast and the tumor size is large requiring extensive excision of breast tissue. However few studies have assessed quality of life (QoL) and objective cosmetic outcome of LDMF in breast cancer surgery. We tried to evaluate those in patients who underwent BCS with or without LDMF. Methods : This study was a prospective, single-center cohort study of patients who underwent LDMF and BCS between 2011 and 2018. As a control, patients who underwent BCS without any volume replacement and the tumor size equal to or greater than 2.5cm on the upper or upper outer of the breast on preoperative imaging. Breast Q questionnaire and body photo were taken at least 1 year after surgery. Two breast surgeons and one plastic surgeon who did not performed LDMF assessed the cosmetic outcome of the patients with photo. Results : 62 patients were in the BCS with LDMF group and 58 patients were in BCS-only group. Pathologic tumor size was significantly larger in LDMF group than BCS-only group (LDMF 3.89cm vs BCS-only 2.92cm, p= 0.001 ). Psychosocial well-being (P= 0.024), physical well-being (P= 0.000), and satisfaction with surgeon (p= 0.006) were significantly better in the BCS-only group than in the LDMF group respectively. But, there were no significant difference in neither sexual well-being (p= 0.286) nor satisfaction for breast (p=0.278) between BCS and LDMF group. In the physicians assessment, there was no significant difference in the cosmetic outcome score between the two groups (LDMF 2.56/4 vs. BCS-only 2.58/4, p= 0.884). Conclusion : In conclusion, physician assessed cosmetic outcome of LDMF was equivalent to that of BCS without LDMF although the tumor size was significantly larger in patients with LDMF. Some inferiority of QoL might be due to postoperative pain or arm movement discomfort. We are planning to evaluate objective cosmetic results using BCCT.core software. Citation Format: Jang-il Kim, Yireh Han, Changjin Lim, Jong-Ho Cheun, Ji Gwang Jung, Hong Kyu Kim, Han-Byoel Lee, Hyeong-Gon Moon, Wonshik Han. Assessment of quality of life and objective cosmetic outcome of breast conserving surgery with or without latissimus dorsi mini-flap in breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-18-14.

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Lichtenberg, Steven, Oxana P. Trifonova, Dmitry L. Maslov, Elena E. Balashova et Petr G. Lokhov. « Metabolomic Laboratory-Developed Tests : Current Status and Perspectives ». Metabolites 11, n^o 7 (26 juin 2021) : 423. http://dx.doi.org/10.3390/metabo11070423.

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Laboratory-developed tests (LDTs) are a subset of in vitro diagnostic devices, which the US Food and Drug Administration defines as “tests that are manufactured by and used within a single laboratory”. The review describes the emergence and history of LDTs. The current state and development prospects of LDTs based on metabolomics are analyzed. By comparing LDTs with the scientific metabolomics study of human bio samples, the characteristic features of metabolomic LDT are shown, revealing its essence, strengths, and limitations. The possibilities for further developments and scaling of metabolomic LDTs and their potential significance for healthcare are discussed. The legal aspects of LDT regulation in the United States, European Union, and Singapore, demonstrating different approaches to this issue, are also provided. Based on the data presented in the review, recommendations were made on the feasibility and ways of further introducing metabolomic LDTs into practice.

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Venable, Paul W., Tyson G. Taylor, Junko Shibayama, Mark Warren et Alexey V. Zaitsev. « Complex structure of electrophysiological gradients emerging during long-duration ventricular fibrillation in the canine heart ». American Journal of Physiology-Heart and Circulatory Physiology 299, n^o 5 (novembre 2010) : H1405—H1418. http://dx.doi.org/10.1152/ajpheart.00419.2010.

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Long-duration ventricular fibrillation (LDVF) in the globally ischemic heart is a common setting of cardiac arrest. Electrical heterogeneities during LDVF may affect outcomes of defibrillation and resuscitation. Previous studies in large mammalian hearts have investigated the role of Purkinje fibers and electrophysiological gradients between the endocardium (Endo) and epicardium (Epi). Much less is known about gradients between the right ventricle (RV) and left ventricle (LV) and within each chamber during LDVF. We studied the transmural distribution of the VF activation rate (VFR) in the RV and LV and at the junction of RV, LV, and septum (Sep) during LDVF using plunge needle electrodes in opened-chest dogs. We also used optical mapping to analyze the Epi distribution of VFR, action potential duration (APD), and diastolic interval (DI) during LDVF in the RV and LV of isolated hearts. Transmural VFR gradients developed in both the RV and LV, with a faster VFR in Endo. Concurrently, large VFR gradients developed in Epi, with the fastest VFR in the RV-Sep junction, intermediate in the RV, and slowest in the LV. Optical mapping revealed a progressively increasing VFR dispersion within both the LV and RV, with a mosaic presence of fully inexcitable areas after 4–8 min of LDVF. The transmural, interchamber, and intrachamber VFR heterogeneities were of similar magnitude. In both chambers, the inverse of VFR was highly correlated with DI, but not APD, at all time points of LDVF. We conclude that the complex VFR gradients during LDVF in the canine heart cannot be explained solely by the distribution of Purkinje fibers and are related to regional differences in the electrical depression secondary to LDVF.

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Kong, Wei, Raymond E. Ideker et Vladimir G. Fast. « Intramural optical mapping of Vm and Cai2+ during long-duration ventricular fibrillation in canine hearts ». American Journal of Physiology-Heart and Circulatory Physiology 302, n^o 6 (15 mars 2012) : H1294—H1305. http://dx.doi.org/10.1152/ajpheart.00426.2011.

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Intramural gradients of intracellular Ca2+ (Cai2+) Cai2+ handling, Cai2+ oscillations, and Cai2+ transient (CaT) alternans may be important in long-duration ventricular fibrillation (LDVF). However, previous studies of Cai2+ handling have been limited to recordings from the heart surface during short-duration ventricular fibrillation. To examine whether abnormalities of intramural Cai2+ handling contribute to LDVF, we measured membrane voltage ( Vm) and Cai2+ during pacing and LDVF in six perfused canine hearts using five eight-fiber optrodes. Measurements were grouped into epicardial, midwall, and endocardial layers. We found that during pacing at 350-ms cycle length, CaT duration was slightly longer (by ≃10%) in endocardial layers than in epicardial layers, whereas action potential duration (APD) exhibited no difference. Rapid pacing at 150-ms cycle length caused alternans in both APD (APD-ALT) and CaT amplitude (CaA-ALT) without significant transmural differences. For 93% of optrode recordings, CaA-ALT was transmurally concordant, whereas APD-ALT was either concordant (36%) or discordant (54%), suggesting that APD-ALT was not caused by CaA-ALT. During LDVF, Vm and Cai2+ progressively desynchronized when not every action potential was followed by a CaT. Such desynchronization developed faster in the epicardium than in the other layers. In addition, CaT duration strongly increased (by ∼240% at 5 min of LDVF), whereas APD shortened (by ∼17%). CaT rises always followed Vm upstrokes during pacing and LDVF. In conclusion, the fact that Vm upstrokes always preceded CaTs indicates that spontaneous Cai2+ oscillations in the working myocardium were not likely the reason for LDVF maintenance. Strong Vm-Cai2+ desynchronization and the occurrence of long CaTs during LDVF indicate severely impaired Cai2+ handling and may potentially contribute to LDVF maintenance.

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Stuckey, Wayne. « Lessons Learned from the Long Duration Exposure Facility ». Journal of the IEST 36, n^o 5 (1 septembre 1993) : 38–42. http://dx.doi.org/10.17764/jiet.2.36.5.5414335137225306.

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The Long Duration Exposure Facility (LDEF) was launched by the space shuttle in April, 1984, and recovered in January, 1990. There were 57 experiments containing over 10,000 specimens to test the effects of the space environment on materials, components, and systems. Originally planned for 1 yr, the exposure actually lasted almost 6 yr. While many LDEF investigations are continuing, results to date have provided valuable information on long-term performance in orbit. Results from the LDEF investigators and the special investigation groups are briefly summarized along with potential benefits from LDEF for future missions.

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Merrigan, Stephen D., et Kamisha L. Johnson-Davis. « A 6 Second Analytical Method for Quantitation of Tacrolimus in Whole Blood by Use of Laser Diode Thermal Desorption Tandem Mass Spectrometry ». Journal of Applied Laboratory Medicine 3, n^o 6 (1 mai 2019) : 965–73. http://dx.doi.org/10.1373/jalm.2018.027243.

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Abstract Background Therapeutic drug monitoring of immunosuppressive drugs is imperative for organ transplant recipients. High-performance LC-MS/MS is considered gold standard; however, immunoassays provide rapid turnaround time. New technology was developed to reduce mass spectrometry analytical run-time. The laser diode thermal desorption source coupled with tandem mass spectrometry (LDTD-MS/MS) eliminates chromatographic separation to increase analytical throughput. Methods A rapid, 6 second, LDTD-MS/MS analytical method was developed for the quantification tacrolimus in whole blood. Whole blood samples were lysed, followed by protein precipitation and solid-phase extraction. Extracted samples with desorption solution were spotted onto a LazWell plate then dried and loaded into the LDTD source for analysis with an AB SCIEX 5500 mass spectrometer in positive multiple reaction monitoring mode. The LDTD laser profile ramps from 0% to 65% of full power over 3 s and is held at 65% for 1 s before returning to initial conditions for 2 s. Results Data presented include tacrolimus by LDTD-MS/MS comparison to LC-MS/MS, sensitivity, imprecision, interference, linearity, and stability. Method comparison between LDTD-MS/MS and a validated in-house LC-MS/MS assay yielded the following: (LDTD-MS/MS) = 1.119 (LC-MS/MS) + 0.23 ng/mL, Sy/x = 1.26, r = 0.9871 (n = 122). The limit of quantification by LDTD-MS/MS for tacrolimus was <0.3 ng/mL and total imprecision was <10%. Conclusions Laser diode thermal desorption tandem mass spectrometry technology can provide rapid turnaround time to result for tacrolimus. The analytical time for LDTD-MS/MS was 6 s compared to 135 s by LC-MS/MS, a >95% decrease in analytical time.

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Biemans Drs, V., E. Savelkoul, G. Dijkstra, M. Simsek, R. Gabriels, M. Pierik, R. West, N. de Boer et F. Hoentjen. « P450 Thioguanine and low dose thiopurines and allopurinol are both safe options after failure of conventional thiopurines : a comparative analysis of two multicentre cohorts ». Journal of Crohn's and Colitis 14, Supplement_1 (janvier 2020) : S404—S405. http://dx.doi.org/10.1093/ecco-jcc/jjz203.579.

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Abstract Background Both thioguanine (TG) and low dose thiopurines and allopurinol (LDTA) can be considered for the treatment of inflammatory bowel disease (IBD) when conventional thiopurines fail due to intolerance or adverse events (AE). However, head-to-head trials are currently not available. The aim of this study was to compare the safety of TG and LDTA in IBD patients. Methods Adult IBD patients who failed conventional thiopurines and initiated LDTA in standard care were identified in the observational prospective multicentre ICC Registry. IBD patients who failed conventional thiopurines and initiated TG were retrospectively enrolled in three university hospitals. Patients with concomitant treatment with biologicals were excluded. The primary outcome was discontinuation of therapy due to AE. Secondary outcomes included: medication-related AE, infections (moderate: oral medication, severe: intravenously administrated medication), hospitalisations, and biological- and corticosteroid-free clinical remission (i.e. physician global assessment = 0) after 104 weeks of treatment. To adjust for confounding and selection bias, both multiple logistic regression and propensity score matching (PSM) were used to correct for baseline characteristics associated with disease severity or therapy refractoriness. Results In total, 182 IBD patients treated with TG (n = 94) or LDTA (n = 88) were included with a median follow-up of 104 weeks (IQR 91–104). The median dose of TG was 0.27 mg/kg (IQR 0.22–0.32), for LDTA: 100 mg allopurinol with either 0.67 mg/kg (IQR 0.54–0.75) azathioprine (n = 45) or 0.35 mg/kg (IQR 0.28–0.38) mercaptopurine (n = 41) (n = 2 unknown). By PSM, 64 TG patients were strictly matched with 64 LDTA patients with comparable baseline characteristics. In total, 19% (TG: 20%, LDTA: 18%) of patients discontinued therapy due AE. After adjusting for confounders, there were no significant differences in terms of discontinuation rate due to AE (TG: n = 19, LDTA = 16, OR 0.50 95% CI 0.15–1.68 p = 0.26), other AE (TG: n = 46, LDTA: n = 44, OR 0.89 95% CI 0.44–1.81 p = 0.75) (no cases of nodular regenerative hyperplasia of the liver were reported), infections (TG: n = 13, LDTA: n = 18, OR 1.05 95% CI 0.40–2.73 p = 0.93), hospitalisations (TG: n = 5, LDTA: n = 9, OR 2.00, 95% CI 0.64–6.23 p = 0.23), or biological- and corticosteroid-free clinical remission (OR 0.74 95% CI 0.33–1.68 p = 0.48). Escalation to biological treatment was comparable (TG 21% vs. LDTA 24% p = 0.68). All these results were in line with the PSM cohort. Conclusion A relative low percentage of patients with prior failure to conventional thiopurines discontinued therapy with TG or LDTA due to AE. Both maintenance therapies may be considered after failure of conventional thiopurines before escalating to biological therapy.

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Guo, Yiduo, Jian Gong et Yu Xiao. « Local Degree of Freedom of Clutter for Reduced-Dimension Space-Time Adaptive Processing with MIMO Radar ». International Journal of Antennas and Propagation 2018 (2018) : 1–9. http://dx.doi.org/10.1155/2018/6026251.

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Degree of freedom (DOF) of clutter in the reduced-dimension (RD) domain, which is called local DOF (LDOF), is of great importance for RD MIMO-STAP (space-time adaptive processing for multiple-input multiple-output radar) algorithms. In this paper, the LDOF equivalence of different RD MIMO-STAP algorithms are firstly proved, and then a generalized LDOF estimation rule under different conditions is developed to estimate the clutter LDOF for MIMO radar effectively. The accuracy of the proposed rule is verified, and how to design RD MIMO-STAP processors under the guidance of the proposed rule is presented through numerical simulations.

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Kadow, Tiffany, Daniel Garcia, Rebecca Minorini, Mark Baratz, Ruth Delaney et Albert Lin. « Latissimus Dorsi Tendon Transfer Vs. Superior Capsular Reconstruction for Treatment of Irreparable Massive Rotator Cuff Tears : A Retrospective Comparison Study with Short-Term Clinical Results ». Orthopaedic Journal of Sports Medicine 7, n^o 7_suppl5 (juillet 2019) : 2325967119S0038. http://dx.doi.org/10.1177/2325967119s00382.

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Objectives: Irreparable massive rotator cuff tears, particularly those that occur in younger patients, represent a particularly challenging clinical scenario with limited options. Treatments such as reverse total shoulder arthroplasty are typically not well indicated for this patient population. We compared two treatment methods, latissimus dorsi tendon transfer (LDTT) vs arthroscopic superior capsular reconstruction (SCR), to determine if one is superior to the other regarding improvement in range of motion (ROM) and patient reported outcomes (PROs). We hypothesize that both treatments would have similar outcomes regarding functional restoration and subjective outcomes. Methods: A retrospective cohort study assessed 43 patients with an irreparable posterosuperior rotator cuff tear after failed conservative or surgical treatment who underwent either LDTT (14 patients, 16 shoulders) or SCR (27 patients, 27 shoulders). Patients with a minimum of 6 month follow-up were included (mean follow up: 17.9 months, 14.9 months respectively). Changes in preoperative and postoperative forward flexion and external rotation were evaluated. Patient reported outcomes (PROs) including ASES, VAS, and SSV were assessed. T-test and Chi-Square statistical tests were performed. Results: The mean age at the time of surgery was 59.9yo vs 60yo for LDTT and SCR respectively (p=0.98). There were significantly more patients in the LDTT group that had undergone prior rotator cuff surgery (p<0.005) and significantly greater number of patients who had subscapularis tears which required repair in patients that underwent SCR (p<0.01). There was no difference in gender (p=0.75). Both cohorts demonstrated similar improvement in forward flexion with mean active forward flexion improving from 123° (90-160°) pre-operatively to 139° (80-180°) postoperatively in the LDTT group (p=0.157) and 85° (0-170°) preoperatively to 138° (40-175°) postoperatively in the SCR group (p =0.001). The average improvement in forward flexion was significantly greater in the SCR group with an improvement of 52° for SCR vs 14° for LDTT (p=0.035). External rotation improved in the LDTT cohort from 41° preoperatively (10-60°) to 62° (10-80°) (p=0.032) while external rotation stayed unchanged for the SCR cohort with 43° preoperatively (0-70°) to 44° (20-80°) postoperatively (p=0.868). The improvement in external rotation was significantly greater in the LDTT cohort with improvement of 19° vs 0.5° in the SCR group (p=0.011). There was no significant difference in reported ASES scores (LDTT: 65.6 vs SCR:70.9)(p=0.569), VAS (LDTT:1.78 vs SCR 2.26) (p=0.645), or SSV (LDTT:55 vs SCR:72.6) (p=0.087). Conclusion: LDTT and SCR both result in functional improvement of motion with SCR improving forward flexion to a greater extent and LDTT improving external rotation to a greater extent. Patient reported outcomes are similar between the two groups at short term follow up. Longer term outcomes are necessary before determining whether one treatment is optimal over the other as well as establishing the appropriate indications for each. [Table: see text]

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Silberberg, José M., Alessandro Nilo et Jorge Roces-García. « Enhancement of External Rotation after Latissimus Dorsi Tendon Transfer (LDTT) : A Cadaveric Study ». Medicina 57, n^o 4 (24 mars 2021) : 305. http://dx.doi.org/10.3390/medicina57040305.

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Background and objectives: Massive rotator cuff tears compromise shoulder mobility function and cannot be directly repaired. Latissimus dorsi tendon transfer (LDTT) is a therapeutic alternative suitable for the treatment of rotator cuff tears that helps to restore external shoulder rotation. Cadaver models have been used for studying the effects of LDTT and procedural variations, but, to the best of our knowledge, none of them have been validated. The aim of our study was to validate a novel cadaver model while verifying the effects of LDTT on external rotation. Materials and Methods: Two groups were included in the study: a cadaver group and a control group made up of healthy volunteers, which were used for the validation of the cadaver model. Baseline external rotation measurements were performed with both groups, after which a massive rotator cuff tear was inflicted and repaired with LDTT in the cadaver group. Their postoperative external rotation was evaluated using three different tests. Results: No statistically significant differences were found between the baseline measurements of the two groups, and postoperative external rotation was significantly higher after LDTT in all cases but one. Conclusions: Cadaver models were validated, since they had a similar preoperative external rotation to healthy volunteers. Moreover, they allowed us to demonstrate the effect of LDTT on external shoulder rotation.

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Dosdall, Derek J., Paul B. Tabereaux, Jong J. Kim, Gregory P. Walcott, Jack M. Rogers, Cheryl R. Killingsworth, Jian Huang, Peter G. Robertson, William M. Smith et Raymond E. Ideker. « Chemical ablation of the Purkinje system causes early termination and activation rate slowing of long-duration ventricular fibrillation in dogs ». American Journal of Physiology-Heart and Circulatory Physiology 295, n^o 2 (août 2008) : H883—H889. http://dx.doi.org/10.1152/ajpheart.00466.2008.

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Endocardial mapping has suggested that Purkinje fibers may play a role in the maintenance of long-duration ventricular fibrillation (LDVF). To determine the influence of Purkinje fibers on LDVF, we chemically ablated the Purkinje system with Lugol solution and recorded endocardial and transmural activation during LDVF. Dog hearts were isolated and perfused, and the ventricular endocardium was exposed and treated with Lugol solution ( n = 6) or normal Tyrode solution as a control ( n = 6). The left anterior papillary muscle endocardium was mapped with a 504-electrode (21 × 24) plaque with electrodes spaced 1 mm apart. Transmural activation was recorded with a six-electrode plunge needle on each side of the plaque. Ventricular fibrillation (VF) was induced, and perfusion was halted. LDVF spontaneously terminated sooner in Lugol-ablated hearts than in control hearts (4.9 ± 1.5 vs. 9.2 ± 3.2 min, P = 0.01). After termination of VF, both the control and Lugol hearts were typically excitable, but only short episodes of VF could be reinduced. Endocardial activation rates were similar during the first 2 min of LDVF for Lugol-ablated and control hearts but were significantly slower in Lugol hearts by 3 min. In control hearts, the endocardium activated more rapidly than the epicardium after 4 min of LDVF with wave fronts propagating most often from the endocardium to epicardium. No difference in transmural activation rate or wave front direction was observed in Lugol hearts. Ablation of the subendocardium hastens VF spontaneous termination and alters VF activation sequences, suggesting that Purkinje fibers are important in the maintenance of LDVF.

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Anderson, Chris. « Lost in LDTs ». Clinical OMICs 3, n^o 10 (novembre 2016) : 28–31. http://dx.doi.org/10.1089/clinomi.03.10.23.

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Hamah Sor, Nadhim, Taghreed Khaleefa Mohammed Ali, Kolimi Shaiksha Vali, Hemn Unis Ahmed, Rabar H. Faraj, Naraindas Bheel et Amir Mosavi. « The behavior of sustainable self-compacting concrete reinforced with low-density waste Polyethylene fiber ». Materials Research Express 9, n^o 3 (1 mars 2022) : 035501. http://dx.doi.org/10.1088/2053-1591/ac58e8.

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Abstract Sustainable concrete production and recycling the construction wastes are of utmost importance for today’s sustainable urban development. In this study, low-density polyethylene waste was recycled in the form of fibers (LDPF) to produce eco-friendly fiber-reinforced sustainable self-compacting concrete (SCC). The content of LDPF ranged from 0.5% to 3.5% at a raise of 0.5% of the mix’s volume. The SCC’s features in fresh and hardened states were tested. The slump flow diameter, T500, V-funnel, and L-box ratio were measured for the fresh properties. The compressive, splitting tensile and flexural strengths were tested at the age of 28 days. However, the outcomes indicated that LPDF had some negative effect on the workability features, but all the results of SCC mixtures were within the standard limitations of SCC except that related to the L-box, which satisfied the standards up to 2% of LDPF. However, the incorporation of LDPF enhanced the mechanical properties, especially the flexural strength. The optimum ratio for the LPDF was 2%, which satisfies the required workability and the highest strength with modulus of elasticity. The thermal conductivity decreased with increasing LDPF content in the SCC mixtures.

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Taylor, Tyson G., Paul W. Venable, Junko Shibayama, Mark Warren et Alexey V. Zaitsev. « Role of KATP channel in electrical depression and asystole during long-duration ventricular fibrillation in ex vivo canine heart ». American Journal of Physiology-Heart and Circulatory Physiology 302, n^o 11 (1 juin 2012) : H2396—H2409. http://dx.doi.org/10.1152/ajpheart.00752.2011.

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Long-duration ventricular fibrillation (LDVF) in the globally ischemic heart is characterized by transmurally heterogeneous decline in ventricular fibrillation rate (VFR), emergence of inexcitable regions, and eventual global asystole. Rapid loss of both local and global excitability is detrimental to successful defibrillation and resuscitation during cardiac arrest. We sought to assess the role of the ATP-sensitive potassium current ( IKATP) in the timing and spatial pattern of electrical depression during LDVF in a structurally normal canine heart. We analyzed endo-, mid-, and epicardial unipolar electrograms and epicardial optical recordings in the left ventricle of isolated canine hearts during 10 min of LDVF in the absence (control) and presence of an IKATP blocker glybenclamide (60 μM). In all myocardial layers, average VFR was the same or higher in glybenclamide-treated than in control hearts. The difference increased with time of LDVF and was overall significant in all layers ( P < 0.05). However, glybenclamide did not significantly affect the transmural VFR gradient. In epicardial optical recordings, glybenclamide shortened diastolic intervals, prolonged action potential duration, and decreased the percentage of inexcitable area (all differences P < 0.001). During 10 min of LDVF, asystole occurred in 55.6% of control and none of glybenclamide-treated hearts ( P < 0.05). In three hearts paced after the onset of asystole, there was no response to LV epicardial or atrial pacing. In structurally normal canine hearts, IKATP opening during LDVF is a major factor in the onset of local and global inexcitability, whereas it has a limited role in overall deceleration of VFR and the transmural VFR gradient.

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Peters, Katharina, Manuel Pazos, Zainab Edoo, Jean-Emmanuel Hugonnet, Alessandra M. Martorana, Alessandra Polissi, Michael S. VanNieuwenhze, Michel Arthur et Waldemar Vollmer. « Copper inhibits peptidoglycan LD-transpeptidases suppressing β-lactam resistance due to bypass of penicillin-binding proteins ». Proceedings of the National Academy of Sciences 115, n^o 42 (1 octobre 2018) : 10786–91. http://dx.doi.org/10.1073/pnas.1809285115.

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The peptidoglycan (PG) layer stabilizes the bacterial cell envelope to maintain the integrity and shape of the cell. Penicillin-binding proteins (PBPs) synthesize essential 4–3 cross-links in PG and are inhibited by β-lactam antibiotics. Some clinical isolates and laboratory strains ofEnterococcus faeciumandEscherichia coliachieve high-level β-lactam resistance by utilizing β-lactam–insensitive LD-transpeptidases (LDTs) to produce exclusively 3–3 cross-links in PG, bypassing the PBPs. InE. coli, other LDTs covalently attach the lipoprotein Lpp to PG to stabilize the envelope and maintain the permeability barrier function of the outermembrane. Here we show that subminimal inhibitory concentration of copper chloride sensitizesE. colicells to sodium dodecyl sulfate and impair survival upon LPS transport stress, indicating reduced cell envelope robustness. Cells grown in the presence of copper chloride lacked 3–3 cross-links in PG and displayed reduced covalent attachment of Braun’s lipoprotein and reduced incorporation of a fluorescentd-amino acid, suggesting inhibition of LDTs. Copper dramatically decreased the minimal inhibitory concentration of ampicillin inE. coliandE. faeciumstrains with a resistance mechanism relying on LDTs and inhibited purified LDTs at submillimolar concentrations. Hence, our work reveals how copper affects bacterial cell envelope stability and counteracts LDT-mediated β-lactam resistance.

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Boztepe, İlker, et Rıza Erdur. « Linked Data Aware Agent Development Framework for Mobile Devices ». Applied Sciences 8, n^o 10 (6 octobre 2018) : 1831. http://dx.doi.org/10.3390/app8101831.

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Due to advances in mobile device and wireless networking technologies, it has already been possible to transfer agent technology into mobile computing environments. In this paper, we introduce the Linked Data Aware Agent Development Framework for Mobile Devices (LDAF-M), which is an agent development framework that supports the development of linked data aware agents that run on mobile devices. Linked data, which is the realization of the semantic web vision, refers to a set of best practices for publishing, interconnecting and consuming structured data on the web. An agent developed using LDAF-M has the ability to obtain data from the linked data environment and internalize the gathered data as its beliefs in its belief base. Besides linked data support, LDAF-M has also other prominent features which are its peer-to-peer based communication infrastructure, compliancy with Foundation for Intelligent Physical Agents (FIPA) standards and support for the Belief Desire Intention (BDI) model of agency in mobile device agents. To demonstrate use of LDAF-M, an agent based auction application has been developed as a case study. On the other hand, LDAF-M can be used in any scenario where systems consisting of agents in mobile devices are to be developed. There is a close relationship between agents and linked data, since agents are considered as the autonomous computing entities that will process data in the linked data environment. However, not much work has been conducted on connecting these two related technologies. LDAF-M aims to contribute to the establishment of the connections between agents and the linked data environment by introducing a framework for developing linked data aware agents.

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Genzen, Jonathan R., Jeffrey S. Mohlman, Jerry L. Lynch, Michael W. Squires et Ronald L. Weiss. « Laboratory-Developed Tests : A Legislative and Regulatory Review ». Clinical Chemistry 63, n^o 10 (1 octobre 2017) : 1575–84. http://dx.doi.org/10.1373/clinchem.2017.275164.

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Abstract BACKGROUND Twenty-five years ago, the Food and Drug Administration (FDA) asserted in a draft document that “home brew” tests—now commonly referred to as laboratory-developed tests (LDTs)—are subject to the same regulatory oversight as other in vitro diagnostics (IVDs)4. In 2010, the FDA began work on developing a proposed framework for future LDT oversight. Released in 2014, the draft guidance sparked an intense debate over potential LDT regulation. While the proposed guidance has not been implemented, many questions regarding LDT oversight remain unresolved. CONTENT This review provides an overview of federal statutes and regulations related to IVDs and clinical laboratory operations, with a focus on those potentially applicable to LDTs and proposed regulatory efforts. Sources reviewed include the Code of Federal Regulations, the Federal Register, congressional hearings, guidance and policy documents, position statements, published literature, and websites. SUMMARY Federal statutes regarding IVDs were passed without substantive evidence of congressional consideration toward the concept of LDTs. The FDA has clear oversight authority over IVD reagents introduced into interstate commerce. A 16-year delay in publicly asserting FDA authority over LDTs, the pursuit of a draft guidance approach toward oversight, and establishment of regulations under the Clinical Laboratory Improvement Amendments of 1988 (CLIA'88) applicable to LDTs contributed to community uncertainty toward LDT oversight. Future regulatory and/or legislative efforts may be required to resolve this uncertainty.

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Little, M. P. « Evidence for dose and dose rate effects in human and animal radiation studies ». Annals of the ICRP 47, n^o 3-4 (13 avril 2018) : 97–112. http://dx.doi.org/10.1177/0146645318756235.

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For stochastic effects such as cancer, linear-quadratic models of dose are often used to extrapolate from the experience of the Japanese atomic bomb survivors to estimate risks from low doses and low dose rates. The low dose extrapolation factor (LDEF), which consists of the ratio of the low dose slope (as derived via fitting a linear-quadratic model) to the slope of the straight line fitted to a specific dose range, is used to derive the degree of overestimation (if LDEF > 1) or underestimation (if LDEF < 1) of low dose risk by linear extrapolation from effects at higher doses. Likewise, a dose rate extrapolation factor (DREF) can be defined, consisting of the ratio of the low dose slopes at high and low dose rates. This paper reviews a variety of human and animal data for cancer and non-cancer endpoints to assess evidence for curvature in the dose response (i.e. LDEF) and modifications of the dose response by dose rate (i.e. DREF). The JANUS mouse data imply that LDEF is approximately 0.2–0.8 and DREF is approximately 1.2–2.3 for many tumours following gamma exposure, with corresponding figures of approximately 0.1–0.9 and 0.0–0.2 following neutron exposure. This paper also cursorily reviews human data which allow direct estimates of low dose and low dose rate risk.

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Benedek, R., D. N. Seidman et L. H. Yang. « Atomistic Simulation of Ceramic/Metal Interfaces : {222}MgO/Cu ». Microscopy and Microanalysis 3, n^o 4 (juillet 1997) : 333–38. http://dx.doi.org/10.1017/s1431927697970252.

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Abstract: Atomistic simulations were performed for the {222}MgO/Cu interface by local density functional theory (LDFT) methods, within the plane-wave-pseudopotential representation, and by (classical) molecular dynamics and statics. The electronic spectra obtained with LDFT calculations showed a localized interface state within the bulk MgO gap, approximately 1 eV above the MgO valence band edge. LDFT adhesive energy calculations, as a function of interface spacing and translations parallel to the interface, were employed to devise an interatomic potential suitable for large-scale atomistic simulation. The interface structure, which was obtained with molecular dynamics (and statics) calculations based on the resultant potential, exhibited a misfit dislocation network with trigonal symmetry, and no standoff dislocations.

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Sastrawan, Muhammad Gandhi, Hasan Sjahrir et Kiki Mohammad Iqbal. « Association of glycated haemoglobin (HbA1C) level with working memory on type-2 diabetes mellitus and prediabetic patients ». International Journal of Research in Medical Sciences 7, n^o 3 (27 février 2019) : 909. http://dx.doi.org/10.18203/2320-6012.ijrms20190947.

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Background: Deleterious effects of diabetic glucose levels on brain structure, have been reported in many studies. Moreover, prediabetic and type-2 diabetes mellitus are associated with lower cognitive function. Author aimed to discover the association of blood glucose and working memory on type 2 diabetic and prediabetic patients.Methods: In this cross-sectional study there are two groups (diabetic and prediabetic) consist of 30 patients each (men 31, women 29). Mean age 40.233±7.862. Blood glucose was measured with HbA1c. All patients were tested with MMSE (Mini Mental State Examination), forward digit span, and backward digit span.Results: There was no difference between diabetic and prediabetic group in MMSE (p 1.000). In diabetic group, mean LDSF (Longest Digit Span Forward) was 5.700±0.877 and there was relation between HbA1c and LDSF (r -0.604). In prediabetic group, mean LDSF was 6.233±0.858 and there was relation between HbA1c and LDSF (r -0.565). There was significant difference between those groups in LDSF (p 0.041). In diabetic group mean LDSB (Longest Digit Span Backward) was 3.767±0.817 and there was relation between HbA1c and LDSB (r -0.545). In prediabetic group, mean LDSB was 4.300±0.750 and there was relation between HbA1c and LDSB (r -0.575). There was significant difference between those groups in LDSB (p 0.024).Conclusions: Results indicated that there was significant difference between diabetic and prediabetic patient in working memory test although there was no difference in general cognitive function.

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Naalla, Ravikiran, Sharmistha Bhattacharyya, Shivangi Saha, Shashank Chauhan et Maneesh Singhal. « Versatility of the Pedicled Latissimus Dorsi Myocutaneous Flap in Reconstruction of Upper Limb and Trunk Soft Tissue Defects ». Journal of Hand and Microsurgery 12, n^o 03 (20 août 2019) : 168–76. http://dx.doi.org/10.1055/s-0039-1694293.

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Abstract Purpose The purpose of the study was to share our indications, technique, outcome, and complications associated with the pedicled latissimus dorsi myocutaneous flap (LDMF) for reconstructing various upper limb and trunk soft tissue defects. Patients and Methods We reviewed the prospectively collected data of the patients who underwent reconstruction of upper limb/trunk soft tissue defects with pedicled LDMF between January 2016 and March 2019. By analyzing the clinical scenarios, the location of flap inset, the arc of rotation, reach of the flap, and associated complications, we put forward few significant findings from our experience. Results Thirty-four patients were included in the study: 13 of them underwent LDMF for coverage of upper limb defects, 12 of them for postradical mastectomy soft tissue defects, 8 for posterior trunk reconstruction, and 1 for sternal wound infection. LDMF was successfully used to cover the scapula, anterior and posterior arms, axilla, cubital fossa, mid-forearm, breast, sternum, and midline dorsal wounds. When used reversely, the flap could cover the exposed spine in the midline dorsum. Three patients (9%) had major complications (two patients had partial flap necrosis which required additional debridement and skin grafting, and one patient required an additional transpositional flap). Three patients had minor complications (managed nonoperatively). Conclusion Pedicled LDMF is a straightforward and versatile option for reconstruction of the varied upper limb and trunk soft tissue defects with minimal complications. Level of Evidence This is a level IV, therapeutic, retrospective study.

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Liu, Shengwang, Jianfei Chen, Jinding Chen, Xiangang Kong, Yuhao Shao, Zongxi Han, Li Feng, Xuehui Cai, Shoulin Gu et Ming Liu. « Isolation of avian infectious bronchitis coronavirus from domestic peafowl (Pavo cristatus) and teal (Anas) ». Journal of General Virology 86, n^o 3 (1 mars 2005) : 719–25. http://dx.doi.org/10.1099/vir.0.80546-0.

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Coronavirus-like viruses, designated peafowl/China/LKQ3/2003 (pf/CH/LKQ3/03) and teal/China/LDT3/2003 (tl/CH/LDT3/03), were isolated from a peafowl and a teal during virological surveillance in Guangdong province, China. Partial genomic sequence analysis showed that these isolates had the S–3–M–5–N gene order that is typical of avian coronaviruses. The spike, membrane and nucleocapsid protein genes of pf/CH/LKQ3/03 had >99 % identity to those of the avian infectious bronchitis coronavirus H120 vaccine strain (Massachusetts serotype) and other Massachusetts serotype isolates. Furthermore, when pf/CH/LKQ3/03 was inoculated experimentally into chickens (specific-pathogen-free), no disease signs were apparent. tl/CH/LDT3/03 had a spike protein gene with 95 % identity to that of a Chinese infectious bronchitis virus (IBV) isolate, although more extensive sequencing revealed the possibility that this strain may have undergone recombination. When inoculated into chickens, tl/CH/LDT3/03 resulted in the death of birds from nephritis. Taken together, this information suggests that pf/CH/LKQ3/03 might be a revertant, attenuated vaccine IBV strain, whereas tl/CH/LDT3/03 is a nephropathogenic field IBV strain, generated through recombination. The replication and non-pathogenic nature of IBV in domestic peafowl and teal under field conditions raises questions as to the role of these hosts as carriers of IBV and the potential that they may have to transmit virus to susceptible chicken populations.

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Parviainen, H., et S. Aigrain. « ldtk : Limb Darkening Toolkit ». Monthly Notices of the Royal Astronomical Society 453, n^o 4 (10 septembre 2015) : 3822–27. http://dx.doi.org/10.1093/mnras/stv1857.

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Zou, Zheng, Ming-Xing Nie, Xing-Sheng Liu et Shi-Jian Liu. « Improved LDTW Algorithm Based on the Alternating Matrix and the Evolutionary Chain Tree ». Sensors 22, n^o 14 (15 juillet 2022) : 5305. http://dx.doi.org/10.3390/s22145305.

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Dynamic time warping under limited warping path length (LDTW) is a state-of-the-art time series similarity evaluation method. However, it suffers from high space-time complexity, which makes some large-scale series evaluations impossible. In this paper, an alternating matrix with a concise structure is proposed to replace the complex three-dimensional matrix in LDTW and reduce the high complexity. Furthermore, an evolutionary chain tree is proposed to represent the warping paths and ensure an effective retrieval of the optimal one. Experiments using the benchmark platform offered by the University of California-Riverside show that our method uses 1.33% of the space, 82.7% of the time used by LDTW on average, which proves the efficiency of the proposed method.

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Magnet, Sophie, Samuel Bellais, Lionel Dubost, Martine Fourgeaud, Jean-Luc Mainardi, Sébastien Petit-Frère, Arul Marie, Dominique Mengin-Lecreulx, Michel Arthur et Laurent Gutmann. « Identification of the l,d-Transpeptidases Responsible for Attachment of the Braun Lipoprotein to Escherichia coli Peptidoglycan ». Journal of Bacteriology 189, n^o 10 (16 mars 2007) : 3927–31. http://dx.doi.org/10.1128/jb.00084-07.

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ABSTRACT The l,d-transpeptidase Ldtfm catalyzes peptidoglycan cross-linking in β-lactam-resistant mutant strains of Enterococcus faecium. Here, we show that in Escherichia coli Ldtfm homologues are responsible for the attachment of the Braun lipoprotein to murein, indicating that evolutionarily related domains have been tailored to use muropeptides or proteins as acyl acceptors in the l,d-transpeptidation reaction.

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Popowitch, Elena B., et Melissa B. Miller. « Performance Characteristics of Xpert Flu/RSV XC Assay ». Journal of Clinical Microbiology 53, n^o 8 (27 mai 2015) : 2720–21. http://dx.doi.org/10.1128/jcm.00972-15.

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The Xpert Flu/RSV XC assay was compared to laboratory-developed tests (LDTs) ( n = 207) and the Xpert Flu assay ( n = 147) using archived nasopharyngeal swabs. The percentages of positive agreements with LDTs were 97.8% for influenza A, 97.2% for influenza B, and 89.3% for RSV. The sensitivity of influenza detection was improved with the Xpert Flu/RSV XC assay compared to the Xpert Flu assay.

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Wang, Ching Kuo. « Biomimically Leg-Kinematics on Walking Robots ». Applied Mechanics and Materials 300-301 (février 2013) : 353–56. http://dx.doi.org/10.4028/www.scientific.net/amm.300-301.353.

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This paper proposes a multi-link algorithm to analyze the walking stability of a self-fabricated, full-size, biomimic, android robot. The stepping trajectory is prescribed and navigated along a horizontal plane without slipping motions and variable center of gravity. However, it may encounter different circumstances for less number of LDOF. Traditionally, walking equilibrium can be assured based on the stabilizable conditions of the dynamic structure of 5-7 leg-degrees of freedom (LDOF). Various kinks of the walking structure are analyzed with the loading effects of the upper-body on the robot. The multi-link fuzzy-logic controller (MLFLC) is also proposed to stabilize the multi-LDOF walking system. Finally, Lyapunov stability can be successfully assured using the proposed controller under the assumption of the theory of the dynamic zero-moment points

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Polat, Erdal. « Larva debridement therapy (LDT) ». Turkiye Aile Hekimligi Dergisi 14, n^o 4 (2010) : 188–91. http://dx.doi.org/10.2399/tahd.10.188.

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Parolini, I., M. Sargiacomo, MP Lisanti et C. Peschle. « Signal transduction and glycophosphatidylinositol-linked proteins (lyn, lck, CD4, CD45, G proteins, and CD55) selectively localize in Triton- insoluble plasma membrane domains of human leukemic cell lines and normal granulocytes ». Blood 87, n^o 9 (1 mai 1996) : 3783–94. http://dx.doi.org/10.1182/blood.v87.9.3783.bloodjournal8793783.

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Src-family nonreceptor protein tyrosine kinases (NRPTK) are associated with cell surface receptors in large detergent-resistant complexes: in epithelial cells, yes is selectively located in vesicle structures containing caveolin (“caveolae”). These formations are typically also endowed with glycophosphatidylinositol (GPI)-anchored proteins. In the present study, we observed lck, lyn, src, hck, CD4, CD45, G proteins, and CD55 (decay-accelerating factor) expression in the buoyant low- density Triton-insoluble (LDTI) fraction of selected leukemic cell lines and granulocytes. We provide a detailed analysis of the two most highly expressed NRPTK, p53/p56lyn and p56lck, which are involved in the transduction of signals for proliferation and differentiation of monocytes/B lymphocytes and T lymphocytes, respectively. We show that lyn is selectively recovered in LDTI complexes isolated from human leukemic cell lines (promyelocytic [HL-60], erythroid [K562] and B- lymphoid [697]) and from normal human granulocytes, and that lck is recovered from LDTI fractions of leukemic T- and B-lymphoid cell lines (CEM, 697). In LDTI fractions of leukemic cells, lck and lyn are enriched 100-fold as compared with the total cell lysates. Analysis of these fractions by electron microscopy shows the presence of 70- to 200- nm vesicles: lyn and lck are homogenously distributed in the vesicles, as revealed by an immunogold labeling procedure. These novel results propose a role for these vesicles in signal transduction mechanisms of normal and neoplastic hematopoietic cells. In support of this hypothesis, we further observed that molecules participating in B- and T-cell receptor activation cofractionate in the LDTI fractions, CD45/lyn (B cells) and CD45/lck/CD4 (T cells).

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Altink, Nienke, Kaj Lambers, Jari Dahmen, Jari Dahmen et Gino Kerkhoffs. « Open Lift, Drill, Fill and Fix (LDFF) for Talar OCDs : 2 to 4 Year Results in 16 Patients ». Foot & ; Ankle Orthopaedics 4, n^o 4 (1 octobre 2019) : 2473011419S0001. http://dx.doi.org/10.1177/2473011419s00010.

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Category: Ankle Introduction/Purpose: The purpose of this study was to describe the mid to long-term clinical and radiological outcomes of an open fixation technique for large primary talar osteochondral defects (OCD): Lift, Drill, Fill and Fix (LDFF). Methods: Nineteen patients underwent an open LDFF surgery. Mean follow-up was 35 months (SD 3.6). Pre-and postoperative clinical assessment included the Foot and Ankle Outcome Score (FAOS) and a numeric rating scale (NRS) on pain at rest and during weight-bearing. Remodeling and bone ingrowth were analyzed on CT at one year post-operatively. Results: 15 out of 19 patients showed remodeling and bone ingrowth after the open LDFF procedure. Patients who did not show remodeling and bone ingrowth were treated by means of an OATS procedure. In the remaining 15 patients available at mid to long-term follow-up, LDFF led to a significant improvement of all FAOS subscales; FAOS-pain improved from 65 to 74 (p=0.014), FAOS-symptoms improved from 60 to 80 (p=0.005), FAOS-ADL improved from 80 to 85 (p=001), FAOS-sport improved from 38 to 61 (p=0.017) and FAOS-QoL improved from 38 to 64 (p=0.025). The NRS of pain at rest significantly improved from 3.2 to 1.2 (p=0.009), and pain during walking significantly improved from 6.5 to 1.6 (p<0.001). No complications occurred. Conclusion: Open LDFF of a talar OCDs show promising mid to long-term clinical and radiological results. A longer follow-up period with more study power is a subsequent necessary step in order to draw firmer conclusions about the longevity of this present procedure.

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Caliendo, Angela M., et Kimberly E. Hanson. « Point-Counterpoint : The FDA Has a Role in Regulation of Laboratory-Developed Tests ». Journal of Clinical Microbiology 54, n^o 4 (20 janvier 2016) : 829–33. http://dx.doi.org/10.1128/jcm.00063-16.

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Since the Food and Drug Administration (FDA) released its draft guidance on the regulation of laboratory-developed tests (LDTs) in October 2014, there has been a flurry of responses from commercial and hospital-based laboratory directors, clinicians, professional organizations, and diagnostic companies. The FDA defines an LDT as an “in vitrodiagnostic device that is intended for clinical use and is designed, manufactured, and used within a single laboratory.” The draft guidance outlines a risk-based approach, with oversight of high-risk and moderate-risk tests being phased in over 9 years. High-risk tests would be regulated first and require premarket approval. Subsequently, moderate-risk tests would require a 510(k) premarket submission to the FDA and low-risk tests would need only to be registered. Oversight discretion would be exercised for LDTs focused on rare diseases (defined as fewer than 4,000 tests, not cases, per year nationally) and unmet clinical needs (defined as those tests for which there is no alternative FDA-cleared or -approved test). There was an open comment period followed by a public hearing in early January of 2015, and we are currently awaiting the final decision regarding the regulation of LDTs. Given that LDTs have been developed by many laboratories and are essential for the diagnosis and monitoring of an array of infectious diseases, changes in their regulation will have far-reaching implications for clinical microbiology laboratories. In this Point-Counterpoint, Angela Caliendo discusses the potential benefits of the FDA guidance for LDTs whereas Kim Hanson discusses the concerns associated with implementing the guidance and why these regulations may not improve clinical care.

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Chapman, Stephen Robert, Mohammed Ibrahim Aladul et Raymond William Fitzpatrick. « Lost cost savings to the NHS in England due to the delayed entry of multiple generic low-dose transdermal buprenorphine : a case scenario analysis ». BMJ Open 9, n^o 8 (août 2019) : e026817. http://dx.doi.org/10.1136/bmjopen-2018-026817.

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ObjectiveOriginator pharmaceutical companies prolonging the patent of a medicine prevents rivals’ entry to the market and competition. As the entry of generic alternatives usually results in price reduction, any delay in their entry potentially deprives the National Health Service (NHS) of much-needed savings. This study estimates the potential cost savings lost to the NHS as a result of delayed entry of generic low-dose buprenorphine (LDTB) patches in England.DesignTwo case scenarios were modelled to determine the savings from the entry of generic LDTB Butec only between February and August 2016 and the potential savings which could have been achieved if all generic LDTB patches had entered the market at the same time.SettingThe volume of utilisation of branded and generic LDTB in UK primary care was derived from the NHS business services authority website for prescriptions dispensed between February 2015 and January 2018.Main outcome measuresCost savings associated with the entry of generic LDTB.ResultsThe cumulative cost savings from the introduction of Butec alone was £0.7 ($0.92) million. The model predicted that if all generic buprenorphine entered the market at the same time with Butec, they could have been achieved a £1.2 ($1.57) million saving. This means that approximately £0.5 ($0.65) million savings was lost to the NHS over the 6-month time period.ConclusionsThe entry of Butec was associated with cost savings. We estimated that more cost savings could have been achieved if other generic LDTB patches had entered the market at the same time to drive competition between rivals. Patent protection strategies which delayed the entry of multiple generics were responsible for the reduced cost savings to the NHS in England.

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Rybakov, V. V. « Logical consecutions in discrete linear temporal logic ». Journal of Symbolic Logic 70, n^o 4 (décembre 2005) : 1137–49. http://dx.doi.org/10.2178/jsl/1129642119.

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AbstractWe investigate logical consequence in temporal logics in terms of logical consecutions, i.e., inference rules. First, we discuss the question: what does it mean for a logical consecution to be ‘correct’ in a propositional logic. We consider both valid and admissible consecutions in linear temporal logics and discuss the distinction between these two notions. The linear temporal logic LDTL, consisting of all formulas valid in the frame 〈L ≤, ≥〉 of all integer numbers, is the prime object of our investigation. We describe consecutions admissible in LDTL in a semantic way—via consecutions valid in special temporal Kripke/Hintikka models. Then we state that any temporal inference rule has a reduced normal form which is given in terms of uniform formulas of temporal degree 1. Using these facts and enhanced semantic techniques we construct an algorithm, which recognizes consecutions admissible in LDTL. Also, we note that using the same technique it follows that the linear temporal logic L(N) of all natural numbers is also decidable w.r.t. inference rules. So, we prove that both logics LDTL and L(N) are decidable w.r.t. admissible consecutions. In particular, as a consequence, they both are decidable (known fact), and the given deciding algorithms are explicit.

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Skedros, John G., et Tanner R. Henrie. « Latissimus Dorsi Tendon Transfer with GraftJacket® Augmentation to Increase Tendon Length for an Irreparable Rotator Cuff Tear ». Case Reports in Orthopedics 2017 (2017) : 1–6. http://dx.doi.org/10.1155/2017/8086065.

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Massive irreparable rotator cuff tears can be reconstructed with latissimus dorsi tendon transfers (LDTT). Although uncommon, the natural length of the latissimus dorsi tendon (LDT) could be insufficient for transfer even after adequate soft tissue releases. Descriptions of cases where grafts were needed to lengthen the LDT are therefore rare. We located only two reports of the use of an acellular dermal matrix to increase effective tendon length in tendon transfers about the shoulder: (1) GraftJacket patch for a pectoralis major tendon reconstruction and (2) ArthroFlex® patch for LDTT. Both of these brands of allograft patches are obtained from human cadavers. These products are usually used to cover soft tissue repairs and offer supplemental support rather than for increasing tendon length. Extending the LDTT with GraftJacket to achieve adequate length, to our knowledge, has not been reported in the literature. We report the case of a 50-year-old male who had a massive, irreparable left shoulder rotator cuff tear that was reconstructed with a LDTT. The natural length of his LDT was insufficient for transfer. This unexpected situation was rectified by sewing two patches of GraftJacket to the LDT. The patient had greatly improved shoulder function at two-year follow-up.

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Blocher, Charles C., et David A. Abwender. « Assessment of Assistive Computer Technology Needs in Students with Learning Disabilities ». Journal of Educational Technology Systems 26, n^o 4 (juin 1998) : 325–30. http://dx.doi.org/10.2190/1erx-wulf-ux3w-k3yq.

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There is an increasing reliance on assistive computer technology (ACT) for children with learning disabilities (e.g., dyslexia), although no formal system exists for prescribing the most appropriate technological assistance. It appears that many professionals responsible for technology assessments use an informal, subjective, intuitive, or trial and error methodology based on previous experience to prescribe assistive computer technologies for students. The Learning Disabilities Technical Assessment (LDTA) is an objective assessment tool designed to assist practitioners in selecting the most appropriate ACT (e.g., peripheral devices, instructional programs) for each individual. A pilot investigation of the LDTA with seventeen students is described. Although most students completed the assessment without difficulty, their experiences indicate that the LDTA can be improved by reprogramming to increase the speed of item presentation, increase the difficulty level of certain items, and revise the “interests” section to yield more theoretically relevant information.

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Lambers, Kaj, Nienke Altink, Jari Dahmen, Sjoerd Stufkens et Gino Kerkhoffs. « Arthroscopic Lift, Drill, Fill and Fix (LDFF) for Talar OCDs Stands the Test of Time : Mean 5 year Follow-Up Results in 25 Patients ». Foot & ; Ankle Orthopaedics 4, n^o 4 (1 octobre 2019) : 2473011419S0026. http://dx.doi.org/10.1177/2473011419s00264.

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Category: Ankle, Arthroscopy Introduction/Purpose: The purpose of this study was to describe the long-term clinical and radiological outcome of a new arthroscopic fixation technique for primary osteochondral talar defects: Lift, Drill, Fill and Fix (LDFF). Methods: Twenty-five patients underwent an arthroscopic LDFF surgery for osteochondral talar defects. Two of these patients underwent surgery on both ankles. During the LDFF technique, the OCD was identified after which an osteochondral flap was created and lifted (lift-phase). The bone flake of the OCD as well as the osteosclerotic area of the bed was drilled (drill phase). Cancellous bone was harvested from the distal tibia and transported into the defect until there was sufficient substantial filling (fill phase). Finally, the osteochondral flap was fixed with an absorbable biocompression screw (fix phase). The mean follow-up was 63 months (SD 9.2). Pre- and postoperative clinical assessment included the Foot and Ankle Outcome Score (FAOS) and the numeric rating scales (NRS) of pain at rest and during walking. Remodeling and bone ingrowth after LDFF were analyzed on computed tomography scans during follow-up at one year after the surgery. Results: All patients were available for final follow-up. At final follow-up, LDFF led to a significant improvement of the NRS of pain during rest and the NRS of pain during walking in all patients. The FAOS significantly improved on all 5 subscales: pain, symptoms, activities of daily living, sport and recreation and quality of life. The NRS of pain at rest significantly improved from 2.3 to 1.0 (p = 0.01), and pain with walking significantly improved from 5.7 to 1.6 (p < 0.001). In total 24 out of 25 patients, and 26 out of 27 ankles, showed remodeling and bone ingrowth on CT scans 1 year after the arthroscopic fixation procedure. No complications occurred. Conclusion: Arthroscopic LDFF of an osteochondral talar defect shows good long-term results at 5 year follow-up after surgery. Although the radiological results at 1-year follow-up and the long-term clinical results are encouraging, more patients and long- term radiological follow-up is necessary in order to identify prognostic factors on outcomes.

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Park, Heanim, Ji Won Seo, Tae Kyung Lee, Jae Hwan Kim, Jong-Eun Kim, Tae-Gyu Lim, Jung Han Yoon Park, Chul Sung Huh, Hee Yang et Ki Won Lee. « Ethanol Extract of Yak-Kong Fermented by Lactic Acid Bacteria from a Korean Infant Markedly Reduces Matrix Metallopreteinase-1 Expression Induced by Solar Ultraviolet Irradiation in Human Keratinocytes and a 3D Skin Model ». Antioxidants 10, n^o 2 (15 février 2021) : 291. http://dx.doi.org/10.3390/antiox10020291.

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Yak-Kong is a type of black soybean that is colloquially referred to as the “medicinal bean” and it elicits several beneficial effects that are relevant to human health, including attenuating the formation of skin wrinkles. It has previously been shown that soybean extracts elicit additional bioactivity that is fermented by lactic acid bacteria. In this study of lactic acid bacteria strains that were isolated from the stools of breast-feeding infants (<100 days old), we selected Bifidobacterium animalis subsp. Lactis LDTM 8102 (LDTM 8102) as the lead strain for the fermentation of Yak-Kong. We investigated the effects of LDTM 8102-fermented Yak-Kong on solar-ultraviolet irradiation (sUV)-induced wrinkle formation. In HaCaT cells, the ethanol extract of LDTM 8102-fermented Yak-Kong (EFY) effectively reduced sUV-induced matrix metalloproteinase-1 (MMP-1) secretion. The effect of EFY was superior to that of unfermented (UFY)- and Lactis KCTC 5854 (another Bifidobacterium animalis species)-fermented Yak-Kong. Additionally, EFY reduced sUV-induced MMP-1 mRNA expression and promoter activity, as well as the transactivation of AP-1 and phosphorylation of ERK1/2 and JNK1/2. Furthermore, EFY alleviated sUV-induced MMP-1 secretion, the destruction of the epidermis, and degradation of collagen in a three-dimensional (3D) skin culture model. EFY had a higher total polyphenol content and anti-oxidative activity than UFY. Twelve metabolites were significantly (≥2-fold) increased in Yak-Kong extract after fermentation by LDTM 8102. Among them, the metabolites of major isoflavones, such as 6,7,4′-trihydroxyisoflavone (THIF), exerted the reducing effect of MMP-1, which indicated that the isoflavone metabolites contributed to the effect of EFY on MMP-1 expression as active compounds. These findings suggest that EFY is a potent natural material that can potentially prevent sUV-induced wrinkle formation.

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De Giacomo, Giuseppe, et Marco Favorito. « Compositional Approach to Translate LTLf/LDLf into Deterministic Finite Automata ». Proceedings of the International Conference on Automated Planning and Scheduling 31 (17 mai 2021) : 122–30. http://dx.doi.org/10.1609/icaps.v31i1.15954.

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The translation from temporal logics to automata is the workhorse algorithm of several techniques in computer science and AI, such as reactive synthesis, reasoning about actions, FOND planning with temporal specifications, and reinforcement learning with non-Markovian rewards, to name a few. Unfortunately, the problem is computationally intractable, requiring the implementation of several heuristics to make it usable in practice. In this paper, following the recent interest in temporal logic formalisms over finite traces, we present a compositional approach for dealing with translations of Linear Temporal Logic (LTLf) and Linear Dynamic Logic (LDLf) on finite traces into Deterministic Finite Automata (DFA). We inductively transform each LTLf/LDLf subformula into a DFA and combine them through automata operators. By relying on efficient semi-symbolic automata representations, we empirically show our approach's effectiveness and competitiveness with similar tools. Moreover, this is the first work that provides a scalable and practical tool supporting the translation to DFA not only for LTLf but also for full LDLf.

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