452 research outputs found

    Relaxation Behavior by Time-Salt and Time-Temperature Superpositions of Polyelectrolyte Complexes from Coacervate to Precipitate

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    Complexation between anionic and cationic polyelectrolytes results in solid-like precipitates or liquid-like coacervate depending on the added salt in the aqueous medium. However, the boundary between these polymer-rich phases is quite broad and the associated changes in the polymer relaxation in the complexes across the transition regime are poorly understood. In this work, the relaxation dynamics of complexes across this transition is probed over a wide timescale by measuring viscoelastic spectra and zero-shear viscosities at varying temperatures and salt concentrations for two different salt types. We find that the complexes exhibit time-temperature superposition (TTS) at all salt concentrations, while the range of overlapped-frequencies for time-temperature-salt superposition (TTSS) strongly depends on the salt concentration (Cs) and gradually shifts to higher frequencies as Cs is decreased. The sticky-Rouse model describes the relaxation behavior at all Cs. However, collective relaxation of polyelectrolyte complexes gradually approaches a rubbery regime and eventually exhibits a gel-like response as Cs is decreased and limits the validity of TTSS.Comment: 12 pages, 5 figures, Follow Gels journal link for latest versio

    Burning a binary tree and its generalization

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    Graph burning is a graph process that models the spread of social contagion. Initially, all the vertices of a graph GG are unburnt. At each step, an unburnt vertex is put on fire and the fire from burnt vertices of the previous step spreads to their adjacent unburnt vertices. This process continues till all the vertices are burnt. The burning number b(G)b(G) of the graph GG is the minimum number of steps required to burn all the vertices in the graph. The burning number conjecture by Bonato et al. states that for a connected graph GG of order nn, its burning number b(G)nb(G) \leq \lceil \sqrt{n} \rceil. It is easy to observe that in order to burn a graph it is enough to burn its spanning tree. Hence it suffices to prove that for any tree TT of order nn, its burning number b(T)nb(T) \leq \lceil \sqrt{n} \rceil where TT is the spanning tree of GG. It was proved in 2018 that b(T)n+n2+1/4+1/2b(T) \leq \lceil \sqrt{n + n_2 + 1/4} +1/2 \rceil for a tree TT where n2n_2 is the number of degree 22 vertices in TT. In this paper, we provide an algorithm to burn a tree and we improve the existing bound using this algorithm. We prove that b(T)n+n2+81b(T)\leq \lceil \sqrt{n + n_2 + 8}\rceil -1 which is an improved bound for n50n\geq 50. We also provide an algorithm to burn some subclasses of the binary tree and prove the burning number conjecture for the same

    Assessment of Readiness of Newly Graduated Health Professionals to Communicate with Patients in Duhok, Kurdistan Region, Iraq

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    Communication Skills (CS) are essential to health workforce to conduct effective professional-patient interaction. In Iraq, majority of newly graduated health professionals are engaged in provision of direct health services. However, undergraduate curricula preparing these professionals include no distinct component to train them on CS. This study aims at assessing the status of CS among Health Professions Education (HPE) graduates of University of Duhok (UoD) and estimating the perception of their patients toward those skills. This cross-sectional study was conducted in 2014. Data on communication skills was obtained, from samples of different health professionals which included: medical doctors (junior residents, nurses, dentists and pharmacists) who recently graduated from different colleges at the UoD. Also, data from was obtained, their patients, to assess their satisfaction of the professionals’ CS. For assessing core CS, a specially designed checklist was adopted from Calgary-Cambridge Guide. Also, senior clinicians were asked on CS performed by their junior residents. Results show that 88% of the senior academic staff regarded CS as “highly essential” and 66% of them were not satisfied with interns’ conduct and suggested that CS should clearly be included in the medical curricula. The basic CS were perceived by patients as either not practiced or wrongly practiced. Patients were unsatisfied with the CS of their attending HPs during observed consultation sessions. The study shows obvious lack of CS among HPE graduates of UoD with patients’ dissatisfaction of their CSs. It seems legitimate to propose that relevant training elements to be designed and incorporated within training modules are needed to realize as a core element of the curriculum of all HPE colleges at the UoD. Keywords: Communication, skills, perception, graduates, Kurdistan-Iraq. DOI: 10.7176/JHMN/73-02 Publication date: April 30th 202

    Do hospital doctors test for thrombophilia in patients with venous thromboembolism?

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    The predictive value of factor V Leiden and the G20210A prothrombin mutation regarding recurrent venous thromboembolism (VTE) is limited and does not influence subsequent patient management. Systematic testing for such genetic thrombophilia should be avoided, but to which extent such testing is practiced in a Swiss Hospital is unknown. To examine the current practice of factor V Leiden and/or G20210A prothrombin mutation testing in a University Hospital, and to assess the clinical consequences of testing on patients. 1388 adult patients (48.7% women) with a main diagnosis of VTE hospitalized at the Lausanne university hospital between January 2013 and December 2015. FV Leiden and/or prothrombin G20210A mutation testing was performed in 61 (4.4%) patients with VTE, an average of 20 patients/year. On multivariable analysis, age < 65 years [odds ratio and (95% confidence interval) 5.91 (3.12-11.19)], being admitted in a medical ward [5.71 (2.02-16.16)] and staying in the intensive care unit [0.34 (0.12-0.97)] were associated with thrombophilia testing. No differences were found between patients with and without testing regarding in-hospital mortality [OR and 95% CI for tested vs. non-tested: 0.23 (0.03-1.73), p = 0.153] and length of stay (multivariable adjusted average ± standard error: 16.9 ± 3.3 vs. 20.0 ± 0.7 days for tested and non-tested patients, respectively, p = 0.875). Thrombophilia testing in hospitalized patients with a main diagnosis of VTE is seldom performed. FV Leiden and/or prothrombin G20210A mutation should not be routinely assessed in patients with acute VTE

    Quality of essential newborn care and neonatal resuscitation at health facilities in Afghanistan:a cross-sectional assessment

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    Objective To assess readiness and quality of essential newborn care and neonatal resuscitation practices in public health facilities in Afghanistan.Design Cross-sectional assessment.Setting 226 public health facilities in Afghanistan, including 77 public health facilities with at least five births per day (high-volume facilities) and 149 of 1736 public health facilities with fewer than five births per day (low-volume facilities).Participants Managers of 226 public health facilities, 734 skilled birth attendants (SBAs) working at these facilities, and 643 women and their newborns observed during childbirth at 77 high-volume health facilities.Outcome measures Availability of knowledgeable SBAs, availability of supplies and compliance with global guidelines for essential newborn care and neonatal resuscitation practices.Results At high-volume facilities, 569/636 (87.9%) of babies were dried immediately after birth, 313/636 (49.2%) were placed in skin-to-skin contact with their mother and 581/636 (89.7%) had their umbilical cord cut with a sterile blade or scissors. A total of 87 newborn resuscitation attempts were observed. Twenty-four of the 87 (27.5%) began to breath or cry after simply clearing the airway or on stimulation. In the remaining 63 (72.5%) cases, a healthcare worker began resuscitation with a bag and mask; however, only 54 (62%) used a correct size of mask and three babies died as their resuscitation with bag and mask was unsuccessful.Conclusions The study indicates room for improvement of the quality of neonatal resuscitation practices at public health facilities in Afghanistan, requiring only strengthening of the current best practices in newborn care. Certain basic and effective aspects of essential newborn care that can be improved on with little additional resources were also missing, such as skin-to-skin contact of the babies with their mother. Improvement of compliance with the standard newborn care practices must be ensured to reduce preventable newborn mortality and morbidity in Afghanistan

    Dual Amplified Spontaneous Emission and Lasing from Nanographene Films

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    Chemically synthesized zigzag-edged nanographenes (NG) have recently demonstrated great success as the active laser units in solution-processed organic distributed feedback (DFB) lasers. Here, we report the first observation of dual amplified spontaneous emission (ASE) from a large-size NG derivative (with 12 benzenoid rings) dispersed in a polystyrene film. ASE is observed simultaneously at the 685 and 739 nm wavelengths, which correspond to different transitions of the photoluminescence spectrum. Ultrafast pump-probe spectroscopy has been used to ascertain the underlying photophysical processes taking place in the films. DFB lasers, based on these materials and top-layer nanostructured polymeric resonators (i.e., one or two-dimensional surface relief gratings), have been fabricated and characterized. Lasers emitting close to either one of the two possible ASE wavelengths, or simultaneously at both of them, have been prepared by proper selection of the resonator parameters.The Alicante team was funded by Spanish Government (MINECO) and European Community (FEDER), grant number MAT2015-66586-R. The researcher R.M-M was funded by a MINECO FPI fellowship (No. BES-2016-077681). The Singapore team was funded by the NRF Investigatorship programme (NRF-NRFI05-2019-0005). The Milan team has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement No. 816313). G.M.P. acknowledges funding from Fondazione Cariplo, grant No. 2018-0979. C.D. and S.S. acknowledge funding from ERC Starting Grant SOLENALGAE (No. 679814)

    Health benefits attributed to 17α-estradiol, a lifespan-extending compound, are mediated through estrogen receptor α.

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    Metabolic dysfunction underlies several chronic diseases, many of which are exacerbated by obesity. Dietary interventions can reverse metabolic declines and slow aging, although compliance issues remain paramount. 17α-estradiol treatment improves metabolic parameters and slows aging in male mice. The mechanisms by which 17α-estradiol elicits these benefits remain unresolved. Herein, we show that 17α-estradiol elicits similar genomic binding and transcriptional activation through estrogen receptor α (ERα) to that of 17β-estradiol. In addition, we show that the ablation of ERα completely attenuates the beneficial metabolic effects of 17α-E2 in male mice. Our findings suggest that 17α-E2 may act through the liver and hypothalamus to improve metabolic parameters in male mice. Lastly, we also determined that 17α-E2 improves metabolic parameters in male rats, thereby proving that the beneficial effects of 17α-E2 are not limited to mice. Collectively, these studies suggest ERα may be a drug target for mitigating chronic diseases in male mammals

    A narrative review of 35 years of meta-[131I]iodobenzylguanidine therapy in neuroblastoma

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    Neuroblastoma is the most common extracranial solid malignancy of childhood. Approximately half of the patients have high-risk neuroblastoma (HR-NBL), typically presenting as widespread metastatic disease at diagnosis. Despite aggressive multimodality treatment, patients with HR-NBL have a long-term survival rate of below 50%. This is primarily due to frequent progression and relapse, which often proves to be therapy resistant. To overcome therapy resistance in HR-NBL, researchers are exploring diverse treatment strategies, including radionuclide therapy. Radiolabelled meta-iodobenzylguanidine (mIBG) has served as a theranostic (therapeutic and diagnostic) radiopharmaceutical in the field of neuroblastoma for several decades. [123I]mIBG scintigraphy is recognized as the international standard to evaluate disease dissemination at diagnosis and to monitor treatment response. In contrast, the role of [131I]mIBG therapy in the management of neuroblastoma is less clear. Over the past 35 years, [131I]mIBG therapy has been studied in more than 1500 patients with neuroblastoma. In initial studies, [131I]mIBG monotherapy was applied as a second-line treatment in patients who failed first-line treatment. In current applications, [131I]mIBG therapy is combined with chemotherapy, radiosensitizers, and/or immunotherapy, and is increasingly integrated in the first-line treatment of HR-NBL. This narrative review provides an overview of the literature on [131I]mIBG therapy in HR-NBL. Studies show that [131I]mIBG therapy can be an effective treatment in one-third of patients with acceptable toxicity. Further investigations, particularly randomized controlled trials, are needed to determine the efficacy and optimal use of [131I]mIBG therapy in HR-NBL
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