Strain-induced kinetics of intergrain defects as the mechanism of slow dynamics in the nonlinear resonant response of humid sandstone bars

A closed-form description is proposed to explain nonlinear and slow dynamics effects exhibited by sandstone bars in longitudinal resonance experiments. Along with the fast subsystem of longitudinal nonlinear displacements we examine the strain-dependent slow subsystem of broken intergrain and interlamina cohesive bonds. We show that even the simplest but phenomenologically correct modelling of their mutual feedback elucidates the main experimental findings typical for forced longitudinal oscillations of sandstone bars, namely, (i) hysteretic behavior of a resonance curve on both its up- and down-slopes, (ii) linear softening of resonant frequency with increase of driving level, and (iii) gradual recovery (increase) of resonant frequency at low dynamical strains after the sample was conditioned by high strains. In order to reproduce the highly nonlinear elastic features of sandstone grained structure a realistic non-perturbative form of strain potential energy was adopted. In our theory slow dynamics associated with the experimentally observed memory of peak strain history is attributed to strain-induced kinetic changes in concentration of ruptured inter-grain and inter-lamina cohesive bonds causing a net hysteretic effect on the elastic Young's modulus. Finally, we explain how enhancement of hysteretic phenomena originates from an increase in equilibrium concentration of ruptured cohesive bonds that are due to water saturation.Comment: 5 pages, 3 figure

On the Hybrid Extension of CTL and CTL+

The paper studies the expressivity, relative succinctness and complexity of satisfiability for hybrid extensions of the branching-time logics CTL and CTL+ by variables. Previous complexity results show that only fragments with one variable do have elementary complexity. It is shown that H1CTL+ and H1CTL, the hybrid extensions with one variable of CTL+ and CTL, respectively, are expressively equivalent but H1CTL+ is exponentially more succinct than H1CTL. On the other hand, HCTL+, the hybrid extension of CTL with arbitrarily many variables does not capture CTL*, as it even cannot express the simple CTL* property EGFp. The satisfiability problem for H1CTL+ is complete for triply exponential time, this remains true for quite weak fragments and quite strong extensions of the logic

Type of intrinsic resistant starch type 3 determines in vitro fermentation by pooled adult faecal inoculum

Resistant starch (RS) results in relatively high health-beneficial butyrate levels upon fermentation by gut microbiota. We studied how physico-chemical characteristics of RS-3 influenced butyrate production during fermentation. Six highly resistant RS-3 substrates (intrinsic RS-3, 80-95 % RS) differing in chain length (DPn 16-76), Mw distribution (PI) and crystal type (A/B) were fermented in vitro by pooled adult faecal inoculum. All intrinsic RS-3 substrates were fermented to relatively high butyrate levels (acetate/butyrate ≤ 2.5), and especially fermentation of A-type RS-3 prepared from polydisperse α-1,4 glucans resulted in the highest relative butyrate amount produced (acetate/butyrate: 1). Analysis of the microbiota composition after fermentation revealed that intrinsic RS-3 stimulated primarily Lachnospiraceae, Bifidobacterium and Ruminococcus, but the relative abundances of these taxa differed slightly depending on the RS-3 physico-chemical characteristics. Especially intrinsic RS-3 of narrow disperse Mw distribution stimulated relatively more Ruminococcus. Selected RS fractions (polydisperse Mw distribution) obtained after pre-digestion were fermented to acetate and butyrate (ratio ≤ 1.8) and stimulated Lachnospiraceae and Bifidobacterium. This study indicates that especially the α-1,4 glucan Mw distribution dependent microstructure of RS-3 influences butyrate production and microbiota composition during RS-3 fermentation.</p

Are we on the right track in DBS surgery for dystonic head tremor?:Polymyography is a promising answer

The clinical benefit of Deep Brain Stimulation (DBS) is associated with electrode positioning accuracy. Intraoperative assessment of clinical effect is therefore key. Evaluating this clinical effect in patients with dystonic head tremor, as opposed to limb tremor, is challenging because the head is fixed in a stereotactic frame. To clinically assess head tremor during surgery, surface electromyography (EMG) electrodes were bilaterally applied to the sternocleidomastoid and cervical paraspinal muscles. This case shows that intraoperative polymyography is an easy and useful tool to assess the clinical effect of DBS electrode positioning

Cardiac myosin-binding protein C mutations and hypertrophic cardiomyopathy haploinsufficiency, deranged phosphorylation, and cardiomyocyte dysfunction

Background-Mutations in the MYBPC3 gene, encoding cardiac myosin-binding protein C (cMyBP-C), are a frequent cause of familial hypertrophic cardiomyopathy. In the present study, we investigated whether protein composition and function of the sarcomere are altered in a homogeneous familial hypertrophic cardiomyopathy patient group with frameshift mutations in MYBPC3 (MYBPC3(mut)). Methods and Results-Comparisons were made between cardiac samples from MYBPC3 mutant carriers (c. 2373dupG, n=7; c. 2864_2865delCT, n=4) and nonfailing donors (n=13). Western blots with the use of antibodies directed against cMyBP-C did not reveal truncated cMyBP-C in MYBPC3(mut). Protein expression of cMyBP-C was significantly reduced in MYBPC3(mut) by 33 +/- 5%. Cardiac MyBP-C phosphorylation in MYBPC3(mut) samples was similar to the values in donor samples, whereas the phosphorylation status of cardiac troponin I was reduced by 84 +/- 5%, indicating divergent phosphorylation of the 2 main contractile target proteins of the beta-adrenergic pathway. Force measurements in mechanically isolated Triton-permeabilized cardiomyocytes demonstrated a decrease in maximal force per cross-sectional area of the myocytes in MYBPC3(mut) (20.2 +/- 2.7 kN/m(2)) compared with donor (34.5 +/- 1.1 kN/m(2)). Moreover, Ca2+ sensitivity was higher in MYBPC3(mut) (pCa(50)=5.62 +/- 0.04) than in donor (pCa(50)=5.54 +/- 0.02), consistent with reduced cardiac troponin I phosphorylation. Treatment with exogenous protein kinase A, to mimic beta-adrenergic stimulation, did not correct reduced maximal force but abolished the initial difference in Ca2+ sensitivity between MYBPC3(mut) (pCa(50)=5.46 +/- 0.03) and donor (pCa(50)=5.48 +/- 0.02). Conclusions-Frameshift MYBPC3 mutations cause haploinsufficiency, deranged phosphorylation of contractile proteins, and reduced maximal force-generating capacity of cardiomyocytes. The enhanced Ca2+ sensitivity in MYBPC3(mut) is due to hypophosphorylation of troponin I secondary to mutation-induced dysfunction. (Circulation. 2009; 119: 1473-1483.

Exploring current physicians’ failure to communicate clinical feedback back to transferring physicians after transitions of patient care responsibility: A mixed methods study

Introduction: After patient care transitions occur, communication from the current physician back to the transferring physician may be an important source of clinical feedback for learning from outcomes of previous reasoning processes. Factors associated with this communication are not well understood. This study clarifies how often, and for what reasons, current physicians do or do not communicate back to transferring physicians about transitioned patients. Methods: In 2018, 38 physicians at two academic teaching hospitals were interviewed about communication decisions regarding 618 transitioned patients. Researchers recorded quantitative and qualitative data in field notes, then coded communication rationales using directed content analysis. Descriptive statistics and mixed effects logistic regression analyses identified communication patterns and examined associations with communication for three conditions: When current physicians 1) changed transferring physicians’ clinical decisions, 2) perceived transferring physicians’ clinical uncertainty, and 3) perceived transferring physicians’ request for communication. Results: Communication occurred regarding 17% of transitioned patients. Transferring physicians initiated communication in 55% of these cases. Communication did not occur when current physicians 1) changed transferring physicians’ clinical decisions (119 patients), 2) perceived transferring physicians’ uncertainty (97 patients), and 3) perceived transferring physicians’ request for communication (12 patients). Rationales for no communication included case contextual, structural, interpersonal, and cultural factors. Perceived uncertainty and request for communication were positively associated with communication (p < 0.001) while a changed clinical decision was not. Discussion: Current physicians communicate infrequently with transferring physicians after assuming patient care responsibilities. Structural and interpersonal barriers to communication may be amenable to change. Clarity about transferring physicians’ uncertainty and desire for communication back may improve clinical feedback communication

Outcome of Endometrial Cancer Stage IIIA with Adnexa or Serosal Involvement Only

Objective. The aim of this study is to look at possible differences in outcome between serosa and adnexal involvement stage IIIA endometrial carcinoma. Methods. 67 patients with stage IIIA endometrial carcinoma were included, 46 with adnexal involvement and 21 with serosa. A central histopathological review was performed. Results. The 7-year locoregional failure rate was (LRFR) 2.2% for adnexal involvement and 16.0% for involvement of the serosa (P = .0522). The 7-year distant metastasis-free survival was 72.7% for adnexal involvement and 58.7% for serosa (P = .3994). The 7-year disease-specific survival (DSS) was 71.8% for patients with adnexal involvement and 75.4% for patients with serosa. Conclusion. Endometrial carcinoma stage IIIA with involvement of the adnexa or serosa showed to have a comparable disease-specific survival. Locoregional control was worse for serosa involvement compared to adnexa

Diesel Engine Exhaust Initiates a Sequence of Pulmonary and Cardiovascular Effects in Rats

This study was designed to determine the sequence of events leading to cardiopulmonary effects following acute inhalation of diesel engine exhaust in rats. Rats were exposed for 2 h to diesel engine exhaust (1.9 mg/m3), and biological parameters related to antioxidant defense, inflammation, and procoagulation were examined after 4, 18, 24, 48, and 72 h. This in vivo inhalation study showed a pulmonary anti-oxidant response (an increased activity of the anti-oxidant enzymes glutathione peroxidase and superoxide dismutase and an increase in heme oxygenase-1 protein, heme oxygenase activity, and uric acid) which precedes the inflammatory response (an increase in IL-6 and TNF-α). In addition, increased plasma thrombogenicity and immediate anti-oxidant defense gene expression in aorta tissue shortly after the exposure might suggest direct translocation of diesel engine exhaust components to the vasculature but mediation by other pathways cannot be ruled out. This study therefore shows that different stages in oxidative stress are not only affected by dose increments but are also time dependent

Self-assembly in solution of a reversible comb-shaped supramolecular polymer

We report a single step synthesis of a polyisobutene with a bis-urea moiety in the middle of the chain. In low polarity solvents, this polymer self-assembles by hydrogen bonding to form a combshaped polymer with a central hydrogen bonded backbone and polyisobutene arms. The comb backbone can be reversibly broken, and consequently, its length can be tuned by changing the solvent, the concentration or the temperature. Moreover, we have proved that the bulkiness of the side-chains have a strong influence on both the self-assembly pattern and the length of the backbone. Finally, the density of arms can be reduced, by simply mixing with a low molar mass bis-urea

Survival after Resection of Multiple Tumor Foci of Intrahepatic Cholangiocarcinoma

Background: Multiple tumor foci of intrahepatic cholangiocarcinoma (ICC) are often considered a contra-indication for resection. We sought to define long-term outcomes after resection of ICC in patients with multiple foci. Methods: Patients who underwent resection for ICC between 1990 and 2017 were identified from 12 major HPB centers. Outcomes of patients with solitary lesions, multiple lesions (ML), and oligometastases (OM) were compared. OM were defined as extrahepatic metastases spread to a single organ. Results: One thousand thirteen patients underwent resection of ICC. On final pathology, 185 patients (18.4%) had ML and 27 (2.7%) had OM. Median survival of patients with a solitary tumor was 43.2 months, while the median survival of patients with 2 tumors was 21.2 months; the median survival of patients with 3 or more tumors was 15.3 months (p < 0.001). Five-year survival was 43.3%, 28.0%, and 8.6%, respectively. The median survival of patients without OM was 37.8 months versus 14.9 months among patients with OM (p < 0.001); estimated 5-year survival was 39.3% and 10.6%, respectively. In multivariable analysis, the presence of two lesions was not an independent poor prognostic factor for OS (HR 1.19; 95%CI 0.90-1.57; p = 0.229). However, the presence of three or more tumors was an independent poor prognostic factor for OS (HR 1.97; 95%CI 1.48-2.64; p < 0.001). Conclusion: Resection of multiple liver tumors for patients with ICC did not preclude 5-year survival: in particular, estimated 5-year OS for resection of two tumors was 28.0%.info:eu-repo/semantics/publishedVersio