The lengths of ten types of cellulose nanofibrils were evaluated by shear viscosity measurement of their dilute dispersions. Aqueous dispersions of surface-carboxylated cellulose nanofibrils with a ...uniform width of ~3 nm were prepared from wood cellulose by 2,2,6,6-tetramethylpiperidine-1-oxyl-mediated oxidation and successive mechanical treatment. Cellulose nanofibril samples with different average lengths were prepared by controlling the conditions of the oxidation or mechanical treatment. The viscosity-average lengths, L ᵥᵢₛc, of the nanofibrils were calculated by applying the shear viscosities of the dilute dispersions to an equation for the dilute region flow behavior of rod-like polymer molecules. The obtained L ᵥᵢₛc values ranged from 1,100 to 2,500 nm and showed a linear relationship to the length-weighted average length, L w, measured by microscopic observation; the relation was described as L ᵥᵢₛc = 1.764 × L w + 764. The influences of the electric double-layer of the nanofibrils and surface-carboxylate content on the value of L ᵥᵢₛc were also investigated.
Autism spectrum disorder (ASD) is a neurodevelopmental disorder associated with deficits in social interactions/communication. Despite the large number of ASD patients, there is no drug approved to ...treat its core symptoms. Recently, Syntocinon (oxytocin nasal spray) has been reported to have a therapeutic effect on ASD. However, the disadvantage of Syntocinon for ASD treatment is that 6 puffs/administration are required to achieve the effective pharmacological dose. Furthermore, there are no published reports evaluating the cerebral distribution profile of oxytocin after intranasal administration. TTA-121 is a newly developed intranasal oxytocin formulation with high bioavailability produced by optimizing the physicochemical properties. In this study, we prepared the same formula as Syntocinon as the control formulation (CF), and the cerebral and extracerebral distribution of oxytocin in rabbits after single intranasal administration of 3H-labeled oxytocin formulations-3HTTA-121 and 3HCF were examined and compared. The area under the concentration-time curve to the time of the last quantifiable concentration (AUCt) in the whole brain was 3.6-fold higher in the 3HTTA-121 group than in the 3HCF group, indicating increased delivery of radioactivity to the brain by TTA-121 than by CF. Since the distribution profiles showed no notable differences in radioactivity between the olfactory bulb and trigeminal nerve, intranasally-administered oxytocin was probably transferred to the brain via both pathways. The results also showed an increase in radioactivity in the prefrontal area and the precuneus, which are probable sites of pharmacological action as shown in clinical studies using functional magnetic resonance imaging (fMRI), confirming that intranasally-administered oxytocin could reach these tissues.
Interval arithmetic libraries provide the four elementary arithmetic operators for operand intervals bounded by floating-point numbers. Actual implementations need to make a large case analysis that ...considers, e.g., magnitude relations between all pairs of argument bounds, positional relations between the arguments and zero, and handling of the special values, ±∞ and NaN. Their correctness is not obvious as they are implemented by human hands, which comes to be critical for the reliability. This work provides a mechanically-verified interval arithmetic library. For this purpose, we utilize the Why3 platform equipped with a specification language for annotated programs and back-end theorem provers. We conduct several proof tasks for each of three properties of the target code: validity, soundness, and tightness; zero division exception handling is also verified for the division code. To accomplish the proof, we propose several techniques for specification/verification. First, we specify additional lemmas that support deductions made by back-end SMT solvers, which enable to discharge proof obligations in floating-point arithmetic containing nonlinear terms. Second, we examine the annotation of tightness, which requires to assume that a computation may result in NaN; we propose specific extremum operators for this purpose. In the experiments, applying the techniques in conjunction with the Alt-Ergo SMT solver and the Coq proof assistant proved the entire code.
Display omitted
We investigated the acceleration and deceleration of wettability-driven liquid transport in arrow-like micropillar arrays. Arrow-shaped pillars were designed by combining a ...microplate-shaped pillar as a shaft, bioinspired by Ligia exotica, with an arrowhead shape. Micropatterned surfaces covered with arrow-like micropillars with a fixed height were conventionally designed and fabricated by lithography. After surface modification, the ability of the surfaces to transport water in the vertical direction from a pool was characterized using the Washburn equation. The design of the arrow-like pillar provided considerable acceleration or deceleration of liquid transport depending on the direction of the arrowhead of the pillar. We found the acceleration and deceleration of liquid transport on the patterned surfaces were derived from anisotropic liquid spreading on a microscopic scale.
Purpose
The recurrence rate of gastroesophageal reflux disease (GERD) after fundoplication has been reported to be 7–25%. We investigated the risk factors for recurrence of GERD after Thal ...fundoplication (TF) in our department with the aim of further reducing the recurrence rate of GERD.
Methods
We retrospectively analyzed 276 patients who underwent TF for GERD at our hospital between 2000 and 2019. Retrospectively considered variables were obtained from the medical records of patients. The variables included patient characteristics, GERD severity, surgery-related factors and postoperative course.
Results
The postoperative GERD recurrence rate was 5.8%. In the univariate analysis, the presence of convulsive seizures (12/4 vs. 110/150,
p
= 0.046) and the absence of a tracheostomy (0/16 vs. 53/207,
p
= 0.048) at the time of TF were significantly associated with recurrence. In the multivariate analysis, the presence of convulsive seizures at the time of TF was the only factor significantly associated with recurrence.
Conclusion
The presence of convulsive seizures and the absence of a tracheostomy at the time of TF were significantly associated with GERD recurrence after TF. Active control of seizures and consideration of surgical indications, including assessment of respiratory status, are important in preventing the recurrence of GERD after TF.
In studies aimed at developing new organic spin materials, we prepared a triisopropylsilylethynyl substituted tri(9-anthryl)methyl (TAntM) radical. The TIPS-ethynyl group in this radical effectively ...suppresses its reactivity, resulting in extremely high stability in air for at least one month. Chemical modification of the radical using 4+2 Diels-Alder reaction proceeds even at room temperature. Because harsh conditions and metal-catalyzed reactions are not required, this post-modification strategy should be highly versatile for use in constructing unique spin-labelled molecules.
The triisopropylsilylethynyl substitute tri(9-anthryl)methyl (
TAntM
) radical is extremely persistent and can be chemically modified directly without harsh conditions or metal catalysts.
In daily life, we perform a variety of sequential tasks while making cognitive decisions to achieve behavioral goals. If transcranial direct current electrical stimulation (tDCS) can be used to ...modulate cognitive functions involved in motor execution, it may provide a new rehabilitation method. In the present study, we constructed a new task in which cognitive decisions are reflected in motor actions and investigated whether the performance of the task can be improved by tDCS of the left dorsolateral prefrontal cortex (DLPFC). Forty healthy participants were randomly assigned to a real or sham tDCS group. The anode electrode was placed at F3 (left DLPFC), and the cathode electrode was positioned in the contralateral supraorbital area. Participants underwent one session of tDCS (1.5 mA, 20 min) and a sequential non-dominant hand task was performed for nine trials before and after tDCS. The task consisted of S1 (a manual dexterity task) and S2 (a manual dexterity task requiring a decision). The results showed the S2 trajectory length was significantly shorter after real tDCS than after sham tDCS (
p
= 0.017), though the S1 trajectory length was not significant. These results suggest that a single tDCS session of the left DLPFC can improve the performance of cognitive tasks complementary to motor execution, but not on dexterity tasks. By elucidating the modulating effect of tDCS on cognitive functions related to motor execution, these results may be used to improve the performance of rehabilitation patients in the future.
This study examined the efficacy of end-ischemic hypothermic oxygenated machine perfusion preservation (HOPE) using an originally developed machine perfusion system for split-liver transplantation. ...Porcine split-liver grafts were created via 75% liver resection after 10 min of warm ischemia. In Group 1, grafts were preserved by simple cold storage (CS) for 8 h (CS group; n = 4). In Group 2, grafts were preserved by simple CS for 6 h and end-ischemic HOPE for 2 h (HOPE group; n = 5). All grafts were evaluated using an isolated ex vivo reperfusion model with autologous blood for 2 h. Biochemical markers (aspartate aminotransferase and lactate dehydrogenase levels) were significantly better immediately after reperfusion in the HOPE group than in the CS group. Furthermore, the HOPE group had a better histological score. The levels of inflammatory cytokines (tumor necrosis factor-α, interferon-γ, interleukin-1β, and interleukin-10) were significantly lower after reperfusion in the HOPE group. Therefore, we concluded that end-ischemic HOPE for split-liver transplantation can aid in recovering the graft function and reducing ischemia-reperfusion injury. HOPE, using our originally developed machine perfusion system, is safe and can improve graft function while attenuating liver injury due to preservation.
•Hydroxyl groups of alginic acid (Alg) were selectively esterified.•Thermoplastic and organosoluble materials were prepared from Alg.•Alg esters showed glass transition between 100 and 200°C.•Thermal ...properties of Alg esters were controlled by side chain length.
Esters derivatives of alginic acid (Alg) were prepared in carboxylic acid/carboxylic acid anhydrides system by using aqueous perchloric acid as the catalyst. Degree of substitution of hydroxyl group of Alg was estimated to be 2, showing that the hydroxyl group of Alg was fully esterified. Alg acid esters showed the solubility to common organic solvents such as acetone and chloroform. In particular, alginic acid hexanoate formed self-standing solvent-cast film, although the film showed brittle mechanical behavior. Furthermore, Alg esters showed glass transition temperature (Tg) in a temperature range between 100 and 200°C, that is in the same range as the conventional synthetic amorphous polymers. It was also shown that the Tg gradually lowered with the increasing acyl side chain length. These results show that Alg esters are plastic materials with tunable organosolubility and thermal properties.
Dynamic viscoelasticity measurements were performed for aqueous dispersions of cellulose nanofibers prepared by TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl radical)-mediated oxidation and subsequent ...mechanical disintegration in water. The frequency dependence of the storage and loss moduli of 0.02% (w/v) dispersions of TEMPO-oxidized cellulose nanofibers in water showed terminal relaxation behavior at relatively lower angular frequencies. This strongly suggests that each cellulose nanofiber in the dispersion behaves as a semiflexible rod-like macromolecular chain or colloidal particle. Furthermore, a clear boundary was observed between the terminal relaxation and rubbery plateau regions. The longest viscoelastic relaxation time, τ, was estimated from the angular frequency, corresponding to the boundary point, and the average length of the cellulose nanofibers, L, was estimated using the equation τ = πηs L 3/18k B T ln(L/d). The equation gave a value of L = 2.2 μm, which was in good agreement with TEM observations.
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