Reversible and Irreversible Interactions of Poly(3-hexylthiophene) with Oxygen Studied by Spin-Sensitive Methods

Understanding of degradation mechanisms in polymer:fullerene bulk-heterojunctions on the microscopic level aimed at improving their intrinsic stability is crucial for the breakthrough of organic photovoltaics. These materials are vulnerable to exposure to light and/or oxygen, hence they involve electronic excitations. To unambiguously probe the excited states of various multiplicities and their reactions with oxygen, we applied combined magneto-optical methods based on multifrequency (9 and 275 GHz) electron paramagnetic resonance (EPR), photoluminescence (PL), and PL-detected magnetic resonance (PLDMR) to the conjugated polymer poly(3-hexylthiophene) (P3HT) and polymer:fullerene bulk heterojunctions (P3HT:PCBM; PCBM = [6,6]-phenyl-C61-butyric acid methyl ester). We identified two distinct photochemical reaction routes, one being fully reversible and related to the formation of polymer:oxygen charge transfer complexes, the other one, irreversible, being related to the formation of singlet oxygen under participation of bound triplet excitons on the polymer chain. With respect to the blends, we discuss the protective effect of the methanofullerenes on the conjugated polymer bypassing the triplet exciton generation

Discharge protocol in acute pancreatitis: an international survey and cohort analysis

There are several overlapping clinical practice guidelines in acute pancreatitis (AP), however, none of them contains suggestions on patient discharge. The Hungarian Pancreatic Study Group (HPSG) has recently developed a laboratory data and symptom-based discharge protocol which needs to be validated. (1) A survey was conducted involving all members of the International Association of Pancreatology (IAP) to understand the characteristics of international discharge protocols. (2) We investigated the safety and effectiveness of the HPSG-discharge protocol. According to our international survey, 87.5% (49/56) of the centres had no discharge protocol. Patients discharged based on protocols have a significantly shorter median length of hospitalization (LOH) (7 (5;10) days vs. 8 (5;12) days) p < 0.001), and a lower rate of readmission due to recurrent AP episodes (p = 0.005). There was no difference in median discharge CRP level among the international cohorts (p = 0.586). HPSG-protocol resulted in the shortest LOH (6 (5;9) days) and highest median CRP (35.40 (13.78; 68.40) mg/l). Safety was confirmed by the low rate of readmittance (n = 35; 5%). Discharge protocol is necessary in AP. The discharge protocol used in this study is the first clinically proven protocol. Developing and testifying further protocols are needed to better standardize patients' care

LHCb: Measurement of the relative yields of the decay modes Bd,s→D(s)±π∓B_{d,s} \to D^{\pm}_{(s)}\pi^{\mp} and Bd,s→D(s)±K±B_{d,s} \to D^{\pm}_{(s)} K^{\pm} and determination of fd/fsf_d /f_s for 7 TeV pppp collisions

A fit to the invariant mass distributions is used to determine the relative abundances of the four decay modes $B_{d,s} \to D^{\pm}_{(s)}\pi^{\mp}$ and $B_{d,s} \to D^{\pm}_{(s)} K^{\mp}$ for $B_{d,s}$ mesons produced in 7 TeV $pp$ collisions at the LHC. From these, the relative branching fractions of the kaon modes with respect to the pion modes, and the value of $f_d /f_s$, are determined

Antibiotic therapy in acute pancreatitis: From global overuse to evidence based recommendations

Background & objectives: Unwarranted administration of antibiotics in acute pancreatitis presents a global challenge. The clinical reasoning behind the misuse is poorly understood. Our aim was to investigate current clinical practices and develop recommendations that guide clinicians in prescribing antibiotic treatment in acute pancreatitis. Methods Four methods were used. 1) Systematic data collection was performed to summarize current evidence; 2) a retrospective questionnaire was developed to understand the current global clinical practice; 3) five years of prospectively collected data were analysed to identify the clinical parameters used by medical teams in the decision making process, and finally; 4) the UpToDate Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system was applied to provide evidence based recommendations for healthcare professionals. Results The systematic literature search revealed no consensus on the start of AB therapy in patients with no bacterial culture test. Retrospective data collection on 9728 patients from 22 countries indicated a wide range (31–82%) of antibiotic use frequency in AP. Analysis of 56 variables from 962 patients showed that clinicians initiate antibiotic therapy based on increased WBC and/or elevated CRP, lipase and amylase levels. The above mentioned four laboratory parameters showed no association with infection in the early phase of acute pancreatitis. Instead, procalcitonin levels proved to be a better biomarker of early infection. Patients with suspected infection because of fever had no benefit from antibiotic therapy. Conclusions The authors formulated four consensus statements to urge reduction of unjustified antibiotic treatment in acute pancreatitis and to use procalcitonin rather than WBC or CRP as biomarkers to guide decision-making

Discharge protocol in acute pancreatitis: an international survey and cohort analysis.

There are several overlapping clinical practice guidelines in acute pancreatitis (AP), however, none of them contains suggestions on patient discharge. The Hungarian Pancreatic Study Group (HPSG) has recently developed a laboratory data and symptom-based discharge protocol which needs to be validated. (1) A survey was conducted involving all members of the International Association of Pancreatology (IAP) to understand the characteristics of international discharge protocols. (2) We investigated the safety and effectiveness of the HPSG-discharge protocol. According to our international survey, 87.5% (49/56) of the centres had no discharge protocol. Patients discharged based on protocols have a significantly shorter median length of hospitalization (LOH) (7 (5;10) days vs. 8 (5;12) days) p < 0.001), and a lower rate of readmission due to recurrent AP episodes (p = 0.005). There was no difference in median discharge CRP level among the international cohorts (p = 0.586). HPSG-protocol resulted in the shortest LOH (6 (5;9) days) and highest median CRP (35.40 (13.78; 68.40) mg/l). Safety was confirmed by the low rate of readmittance (n = 35; 5%). Discharge protocol is necessary in AP. The discharge protocol used in this study is the first clinically proven protocol. Developing and testifying further protocols are needed to better standardize patients' care

Search for D∗(2007)0→μ+μ−D^{*}(2007)^0\to\mu^+\mu^- in B−→π−μ+μ−B^-\to\pi^-\mu^+\mu^- decays

International audienceThe very rare $D^{*}(2007)^0\to\mu^+\mu^-$ decay is searched for by analysing $B^-\to\pi^-\mu^+\mu^-$ decays. The analysis uses a sample of beauty mesons produced in proton-proton collisions collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 9 fb$^{-1}$. The signal signature corresponds to simultaneous peaks in the $\mu^+\mu^-$ and $\pi^-\mu^+\mu^-$ invariant masses. No evidence for an excess of events over background is observed and an upper limit is set on the branching fraction of the decay at ${\cal B}(D^{*}(2007)^0\to\mu^+\mu^-) < 2.6\times 10^{-8}$ at $90\%$ confidence level. This is the first limit on the branching fraction of $D^{*}(2007)^0\to\mu^+\mu^-$ decays and the most stringent limit on $D^{*}(2007)^0$ decays to leptonic final states. The analysis is the first search for a rare charm-meson decay exploiting production via beauty decays

Search for CPCP violation in the phase space of D0→π−π+π0D^0 \to \pi^-\pi^+\pi^0 decays with the energy test

International audienceA search for $CP$ violation in $D^0 \to \pi^-\pi^+\pi^0$ decays is reported, using $pp$ collision data collected by the LHCb experiment from 2015 to 2018 corresponding to an integrated luminosity of 6$fb^{-1}$. An unbinned model-independent approach provides sensitivity to local $CP$ violation within the two-dimensional phase space of the decay. The method is validated using the Cabibbo-favoured channel \D^0 \to \K^-\pi^+\pi^0 and background regions of the signal mode. The results are consistent with $CP$ symmetry in this decay