Cells exposed to extreme physicochemical or mechanical stimuli die in an uncontrollable manner, as a result of their immediate structural breakdown. Such an unavoidable variant of cellular demise is ...generally referred to as 'accidental cell death' (ACD). In most settings, however, cell death is initiated by a genetically encoded apparatus, correlating with the fact that its course can be altered by pharmacologic or genetic interventions. 'Regulated cell death' (RCD) can occur as part of physiologic programs or can be activated once adaptive responses to perturbations of the extracellular or intracellular microenvironment fail. The biochemical phenomena that accompany RCD may be harnessed to classify it into a few subtypes, which often (but not always) exhibit stereotyped morphologic features. Nonetheless, efficiently inhibiting the processes that are commonly thought to cause RCD, such as the activation of executioner caspases in the course of apoptosis, does not exert true cytoprotective effects in the mammalian system, but simply alters the kinetics of cellular demise as it shifts its morphologic and biochemical correlates. Conversely, bona fide cytoprotection can be achieved by inhibiting the transduction of lethal signals in the early phases of the process, when adaptive responses are still operational. Thus, the mechanisms that truly execute RCD may be less understood, less inhibitable and perhaps more homogeneous than previously thought. Here, the Nomenclature Committee on Cell Death formulates a set of recommendations to help scientists and researchers to discriminate between essential and accessory aspects of cell death.
Spectrometric techniques for the analysis of trace cadmium have developed rapidly due to the increasing need for accurate measurements at extremely low levels of this element in diverse matrices. ...This review covers separation and preconcentration procedures, such as electrochemical deposition, precipitation, coprecipitation, solid phase extraction, liquid–liquid extraction (LLE) and cloud point extraction (CPE), and consider the features of the their application with several spectrometric techniques.
Propôs-se, neste trabalho, estudar os efeitos da salinidade da água de irrigação sobre a produção do pinhãomanso (Jatropha curcas L.) após poda realizada aos 396 dias após a semeadura--DAS, em ...ambiente protegido. A pesquisa foi desenvolvida entre maio de 2008 e janeiro de 2009. A cultura foi conduzida em lisímetros de drenagem (200 L) contendo 230 kg de material de solo, Argissolo Acinzentado, devidamente adubado e corrigido. Testaram-se cinco níveis de condutividade elétrica da água de irrigação--CEa (0,6; 1,2; 1,8; 2,4 e 3,0 dS m.sup.-1, a 25gradosC). Empregou-se o delineamento experimental em blocos inteiramente casualizados, com quatro repetições. As plantas foram podadas a 80 cm, ao final do primeiro ciclo de produção. Aos 240 dias após a poda (DAPd), plantas irrigadas com água de 3,0 dS m.sup.-1 tiveram o número de cachos reduzido em 93%, o peso médio das cascas, das sementes e dos frutos e número de frutos por planta reduzidos em 97%. Os pesos médios do fruto e da semente foram reduzidos em 67 e 49%, respectivamente. Plantas irrigadas com água de 0,6 dS m.sup.-1 e 3,0 dS m.sup.-1 produziram 32,03 e 22,5% de óleo, respectivamente. Palavras-chave: irrigação, condutividade elétrica, Jatropha curcas L., biodiesel The objective of this work was to evaluate the effects of the irrigation with saline water on production of physic nut (Jatropha curcas L.) after pruning (396 days after sowing). Between May 2008 and January 2009, the experiment was carried out in a greenhouse. The plants were grown in drainage lysimeters (200L) containing 230 kg of non-saline and non-sodic soil properly fertilized, classified as Gray Argisoil Eutrophic. Treatments consisted of five levels of electrical conductivity of the irrigation water--ECw (0.6; 1.2; 1.8; 2.4 and 3.0 dS m.sup.-1, at 25degreesC). All the plants were pruned at 80 cm height. At 240 days after pruning the variables: number of bunches, weight of main of scab, seeds and fruits, weights of seed and fruit, number of fruits and oil content were evaluated. Plants irrigated with water of 3.0 dS m.sup.-1 were significantly affected with the following reductions: 93% in number of bunches, 97% in the variables weight of scab, of seeds and fruits, and number of fruits; 67% in fruit weight, and 49% in seed weight. Oil content of plants irrigated with water of 3.00 dS m.sup.-1 had reduction of 30.56%. Key words: irrigation, electrical conductivity, Jatropha curcas L., biodiesel
Neutrino-induced coherent charged pion production on nuclei νμA→μ(±)π(∓)A is a rare, inelastic interaction in which a small squared four-momentum |t| is transferred to the recoil nucleus, leaving it ...intact in the reaction. In the scintillator tracker of MINERvA, we remove events with evidence of particles from nuclear breakup and reconstruct |t| from the final-state pion and muon. We select low |t| events to isolate a sample rich in coherent candidates. By selecting low |t| events, we produce a model-independent measurement of the differential cross section for coherent scattering of neutrinos and antineutrinos on carbon. We find poor agreement with the predicted kinematics in neutrino generators used by current oscillation experiments.
This paper presents a dual-core lockstep (DCLS) implementation to protect hard-core processors against radiation-induced soft errors. The proposed DCLS is applied to an Advanced RISC Machine ...Cortex-A9 embedded processor. Different software optimizations were evaluated to assess their impact on performance and fault tolerance. Heavy ions' experiments and fault injection emulation were performed to analyze the system susceptibility to errors and the DCLS performance. Results show that the approach is able to decrease the system cross section and achieve high protection against errors. The DCLS successfully protects the system from up to 78% of the injected faults. The execution performance analysis shows that by reducing the number of verifications and augmenting the block partition execution time, it is possible to increase the system reliability with minimal performance losses.
Aim
To assess the impact of mechanical overinstrumentation of root canals in extracted teeth on the development of dentinal microcracks in the apical portion of the root by means of micro‐computed ...tomographic (micro‐CT) analysis. Root canal preparation short of the canal terminus and at the apical foramen (AF) were used as controls.
Methodology
Twenty 2‐rooted maxillary premolars with two canals were selected, scanned in a micro‐CT device and the root canals prepared sequentially using Reciproc M‐Wire R25 instruments to working lengths: 1 mm short of the AF (AF − 1 mm), at the AF (AF), and overinstrumentation (AF + 1 mm). A micro‐CT scan of each specimen was performed after each time point. After reconstruction and co‐registration procedures, the images were screened from the cementoenamel junction to the apex (n = 55 352) to identify the presence of dentinal microcracks in the apical third of the root.
Results
After the analyses of 55 352 slices, dentinal microcracks were visualized in 12.45% of the images (6892 slices), with 5.73% (3174 slices) in the cervical, 3.57% (1976 slices) in the middle and 3.15% (1740 slices) in the apical third. All dentinal microcracks observed at all time points (AF − 1 mm, AF and AF + 1 mm) were already present in the corresponding images before canal instrumentation. Therefore, no new microcracks were detected, regardless of the working length used for canal instrumentation.
Conclusion
Reciprocating root canal preparation either short, at or beyond the AF (overinstrumentation) did not create dentinal microcracks in the roots of extracted 2‐rooted maxillary premolars.
Trypanosoma cruzi, the etiologic agent of Chagas disease, is currently divided into six discrete typing units (DTUs), named TcI-TcVI. CL Brener, the reference strain of the T. cruzi genome project, ...is a hybrid with a genome assembled into 41 putative chromosomes. Gene copy number variation (CNV) is well documented as an important mechanism to enhance gene expression and variability in T. cruzi. Chromosomal CNV (CCNV) is another level of gene CNV in which whole blocks of genes are expanded simultaneously. Although the T. cruzi karyotype is not well defined, several studies have demonstrated a significant variation in the size and content of chromosomes between different T. cruzi strains. Despite these studies, the extent of diversity in CCNV among T. cruzi strains based on a read depth coverage analysis has not been determined.
We identify the CCNV in T. cruzi strains from the TcI, TcII and TcIII DTUs, by analyzing the depth coverage of short reads from these strains using the 41 CL Brener chromosomes as reference. This study led to the identification of a broader extent of CCNV in T. cruzi than was previously speculated. The TcI DTU strains have very few aneuploidies, while the strains from TcII and TcIII DTUs present a high degree of chromosomal expansions. Chromosome 31, which is the only chromosome that is supernumerary in all six T. cruzi samples evaluated in this study, is enriched with genes related to glycosylation pathways, highlighting the importance of glycosylation to parasite survival.
Increased gene copy number due to chromosome amplification may contribute to alterations in gene expression, which represents a strategy that may be crucial for parasites that mainly depend on post-transcriptional mechanisms to control gene expression.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The discovery of chirped pulse amplification has led to great improvements in laser technology, enabling energetic laser beams to be compressed to pulse durations of tens of femtoseconds and focused ...to a few micrometers. Protons with energies of tens of MeV can be accelerated using, for instance, target normal sheath acceleration and focused on secondary targets. Under such conditions, nuclear reactions can occur, with the production of radioisotopes suitable for medical application. The use of high-repetition lasers to produce such isotopes is competitive with conventional methods mostly based on accelerators. In this paper, we study the production of 67Cu, 63Zn, 18F, and 11C, which are currently used in positron emission tomography and other applications. At the same time, we study the reactions 10B(p,α)7Be and 70Zn(p,4n)67Ga to put further constraints on the proton distributions at different angles, as well as the reaction 11B(p,α)8Be relevant for energy production. The experiment was performed at the 1 PW laser facility at Vega III in Salamanca, Spain. Angular distributions of radioisotopes in the forward (with respect to the laser direction) and backward directions were measured using a high purity germanium detector. Our results are in reasonable agreement with numerical estimates obtained following the approach of Kimura and Bonasera Nucl. Instrum. Methods Phys. Res., Sect. A 637, 164–170 (2011).
Loss to follow-up is a major challenge for very preterm (VPT) cohorts; attrition is associated with social disadvantage and parents with impaired children may participate less in research. We ...investigated the impact of loss to follow-up on the estimated prevalence of neurodevelopmental impairment in a VPT cohort using different methodological approaches.
This study includes births < 32 weeks of gestational age (GA) from 4 regions in the UK and Portugal participating in a European birth cohort (N = 1737 survivors). Data on maternal characteristics, pregnancy complications, neonatal outcomes and neighborhood deprivation were collected at baseline. Neurodevelopment was assessed at 2 years of corrected age (CA) using standardized parent-report measures. We applied (1) multiple imputation (MI) and (2) inverse probability weighting (IPW) to estimate the impact of non-response on the prevalence of moderate to severe neurodevelopmental impairment and assessed violations of the missing at random (MAR) assumption using the delta method.
54.2% of children were followed-up. Follow-up was less likely when mothers were younger, multiparous, foreign-born, did not breastfeed and came from deprived areas. The prevalence of neurodevelopmental impairment was 18.4% (95% confidence interval (CI):15.9-21.1) and increased to 20.4% (95%CI: 17.3-23.4) and 20.0% (95%CI:16.9-23.1) for MI and IPW models, respectively. Simulating strong violations of MAR (children with impairments being 50% less likely to be followed-up) raised estimates to 23.6 (95%CI:20.1-27.1) CONCLUSIONS: In a VPT cohort with high loss to follow-up, correcting for attrition yielded modest increased estimates of neurodevelopmental impairment at 2 years CA; estimates were relatively robust to violations of the MAR assumption.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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