Monte Carlo track-structure simulation provides a near accurate description of the passage of charge particle in water as a surrogate for biological tissue. Radiation transport codes and Monte Carlo ...track-structure codes are widely used in radiation biophysics, dosimetry and microdosimetry, clinical radiotherapy, in space radiation program and accelerator design and research. Over the past decade the number of Monte Carlo track codes simulating a variety of different types of radiations has increased rapidly. In this paper we provide a review of recent progress in the development of particle track simulation for electron, low-energy light ions and finally the recent model development for the low-energy electron cross-sections in liquid water.
Aims
To evaluate the potential use of synthetic oligonucleotides as a standard curve for proviral load (PVL) of human T‐cell leukaemia virus type 1 (HTLV‐1) quantification in peripheral blood ...mononuclear cells (PBMC) of HTLV‐1‐infected individuals by quantitative real‐time polymerase chain reaction (qPCR) analysis.
Methods and results
Synthetic oligonucleotides based on HTLV‐1 genome were customized to use as a standard curve. Twelve anti‐HTLV‐1‐positive samples with known HTLV‐1 PVL, previously quantified by qPCR assay using TARL‐2 cells as a conventional standard curve, were submitted to the new protocol. The proviral quantification levels had a high concordance with qPCR results using a conventional standard curve. The results demonstrate that the conventional standard curve can be replaced by a synthetic standard curve due to its ability to quantification based on the linearity and qPCR efficiency and similar results with a validated qPCR assay using a conventional standard curve.
Conclusions
Synthetic oligonucleotides standard curves could be a very useful tool on HTLV‐1 diagnosis and absolute HTLV‐1 PVL quantification.
Significance and Impact of the Study
HTLV‐1 PVL determination using synthetic oligonucleotides standard curve by qPCR could be a helpful alternative for the laboratories that monitor infected patients as an important prognostic factor in HTLV‐1‐associated diseases progression. Also, it can decrease costs and overcome the biological limitations of the plasmid curve.
Permeability k is expressed as a product of the hydraulic radius Rh (=pore volume Vp/sample surface area S) squared, porosity ϕ, and a nondimensional geometrical factors 1/G. G is often assumed ...constant depending on the model, partly because its measurement is difficult. We propose a method to measure G without assuming any microstructural model, and present its evolution during compaction of sedimentary rocks that are too fine-grained to observe and quantify microstructures. We measured S, k, Vp, and grain volume Vg during compaction with confining pressure up to 100 MPa of diatomaceous mudstone from Koetoi Formation (Kdm, ϕ = 0.53–0.64) and siliceous mudstone from Wakkanai Formation (Wsm, ϕ = 0.28–0.33), Horonobe, Japan. They are similar sedimentary rocks, but are different in the grade of diagenesis. Vp and S yield Rh, and thus we can estimate G. G for Kdm remains nearly constant during compaction and varies from 1.3 to 6, whereas G for some samples from less porous Wsm increases irreversibly with compaction from about 0.1 to 10. The increase in G by 2 orders of magnitude probably indicates the change in the dominant fluid conduit from concentrated flow along fractures to pervasive flow.
•We proposed a method to estimating geometrical factor for permeability without assuming any model.•Permeability, porosity and surface area of two sedimentary rocks were measured.•Hydraulic radius and geometrical factor were estimated using experimental results.•Change in the geometrical factor indicates the change in the dominant fluid conduit.
Introduction Humans can acquire new motor behaviors via different forms of learning- positive reinforcement and the formation of internal model representations of the movement dynamics (adaptation). ...The neurophysiological mechanisms in the primary motor cortex (M1) and the cerebellum (CB) when learning motor tasks through reinforcement or adaptation are poorly understood. Objectives To investigate neurophysiological underpinnings of distinct learning mechanisms. Materials and methods We assessed M1 LTP-like plasticity and cerebellar excitability changes when healthy participants learned a reaching adaptation task, known to rely early on adaptation and later on reinforcement mechanisms. We determined the presence of LTP-like plasticity when we observed no significant increase in M1 excitability even after applying anodal tDCS (i.e. occlusion of M1 LTP-like plasticity), as determined by single pulse TMS-evoked potentials. We evaluated cerebellar inhibition (CBI) to indirectly investigate CB excitability changes during learning, using a paired-pulse TMS paradigm comprised of conditioning CB stimulation followed by a test M1 stimulation. We also assessed these physiological markers when participants learned the same reaching via binary feedback, which relies on reinforcement mechanisms. Results We found occlusion of M1 LTP-like plasticity only late, but not in the early phase of adaptation learning, whereas CBI changed early but not in the later phase of learning. We also found occlusion of M1 LTP-like plasticity when participants successfully learned the same reaching action via binary feedback. However, CBI did not change in this task. Conclusion We show a clear double dissociation whereby learning a task via reinforcement results in M1 LTP-like plasticity changes, while learning the motor actions via adaptation leads to cerebellar plasticity modifications. This indicates that learning motor actions can be accomplished by different neurophysiological mechanisms and neural substrates. Furthermore, deficits in one learning mechanism could be compensated by another intact mechanism, opening alternative interventions to enhance motor function after neurological disease.
Juvenile Japanese flounder Paralichthys olivaceus inhabit shallow sandy areas and consume chiefly mysids. Hatchery-reared P. olivaceus (ca. 100 mm in total length) released in stock enhancement ...programs also consume mysids. To examine whether stocking is implemented within the available carrying capacity, we assessed the feeding relationships among fishes, based on the stomach contents of fishes collected off the coast of Fukushima, Japan. Similarity in diet suggested that 10 species, particularly the poacher Occella iburia and nibe croaker Nibea mitsukurii were potential competitors of P. olivaceus juveniles for food. Large inter-annual variability in the abundance of these competitors was observed, suggesting variability in their consumption of mysids. The predominant mysid Orientomysis mitsukurii was abundant every year, and growth rates of wild P. olivaceus, estimated from otolith microstructure, were mostly high (>1 mm d−1), even in the year when wild P. olivaceus were highly abundant. In our statistical model, abundance of mysids and consumption of mysids by fishes significantly affected the growth rates of wild P. olivaceus but only accounted for a small proportion (i.e. explained 2.2 and 2.4% of variance, respectively) of the total compared to the body size of juveniles (30.0%) and bottom water temperature (4.5%). These results suggest that the productivity of mysids is usually high enough to support the production of mysid consumers, but exceptionally high abundances of wild P. olivaceus or other competitors can reduce the available carrying capacity. In such a situation, stocking should be restricted so as not to reduce productivity of wild fishes.
Abstract The purpose of this study was to estimate the width of free margin with a significant impact on local recurrence in surgical resection of oral squamous cell carcinoma (OSCC). Clinical and ...pathological data of 127 consecutive patients who underwent radical resection of OSCC were analyzed retrospectively. The local control rate was compared between patients with clear, close, and involved surgical margins, changing the required width of free margin for the definition of ‘close surgical margin’ (from 1 to 5 mm). If a free margin of within 1, 2, or 4 mm was judged a close margin, the risk of local recurrence was significantly different among the patients with clear, close, and involved surgical margins. If the definition of close margin was within 5 mm of the resection margin, the difference between clear and close margin did not reach statistical significance. The results of this study suggest that 5 mm of clearance at the surgical resection margin should be the index of oncological surgery. More than 5 mm of histological free margin around OSCC is not justified in terms of the risk management of local recurrence and the resultant morbidity.
Common marmosets (Callithrix jacchus) are attracting attention as animal models in preclinical studies for drug development. However, cytochrome P450s (P450s), major drug-metabolizing enzymes, have ...not been fully identified and characterized in marmosets. In this study, based on the four novel P450 4F genes found on the marmoset genome, we successfully isolated P450 4F2, 4F3B, 4F11, and 4F12 cDNAs in marmoset livers. Deduced amino acid sequences of the four marmoset P450 4F forms exhibited high sequence identities (87%-93%) to the human and cynomolgus monkey P450 4F homologs. Marmoset P450 4F3B and 4F11 mRNAs were predominantly expressed in livers, whereas marmoset P450 4F2 and 4F12 mRNAs were highly expressed in small intestines and livers. Four marmoset P450 4F proteins heterologously expressed in Escherichia coli catalyzed the ω-hydroxylation of leukotriene B4 In addition, marmoset P450 4F12 effectively catalyzed the hydroxylation of antiallergy drug ebastine, a human P450 2J/4F probe substrate. Ebastine hydroxylation activities by small intestine and liver microsomes from marmosets and cynomolgus monkeys showed greatly higher values than those of humans. Ebastine hydroxylation activities by marmoset and cynomolgus monkey small intestine microsomes were inhibited (approximately 60%) by anti-P450 4F antibodies, unlike human small intestine microsomes, suggesting that contribution of P450 4F enzymes for ebastine hydroxylation in the small intestine might be different between marmosets/cynomolgus monkeys and humans. These results indicated that marmoset P450 4F2, 4F3B, 4F11, and 4F12 were expressed in livers and/or small intestines and were functional in the metabolism of endogenous and exogenous compounds, similar to those of cynomolgus monkeys and humans.
PDF
