Laser-induced frequency tuning of Fourier-limited single-molecule emitters

The local interaction of charges and light in organic solids is the basis of distinct and fundamental effects. We here observe, at the single molecule scale, how a focused laser beam can locally shift by hundreds-time their natural linewidth and in a persistent way the transition frequency of organic chromophores, cooled at liquid helium temperatures in different host matrices. Supported by quantum chemistry calculations, the results are interpreted as effects of a photo-ionization cascade, leading to a stable electric field, which Stark-shifts the molecular electronic levels. The experimental method is then applied to a common challenge in quantum photonics, i.e. the independent tuning and synchronization of close-by quantum emitters, which is desirable for multi-photon experiments. Five molecules that are spatially separated by about 50 microns and originally 20 GHz apart are brought into resonance within twice their linewidth. Combining this ability with an emission linewidth that is only limited by the spontaneous decay, the system enables fabrication-free, independent tuning of multiple molecules integrated on the same photonic chip.Comment: 15 pages, 5 figures. Supplementary Informations 23 pages, 13 figure

The use of complementary serological and molecular testing for blood-borne pathogens and evaluation of socio-demographic characteristics of intravenous drug users on substitution therapy from Šumadia district of Serbia

© 2019 Inst. Sci. inf., Univ. Defence in Belgrade. All rights reserved. Background/Aim: Intravenous drug users (IDUs) are still a high risk-group for cross-reacting blood-borne infections, for vertical pathogen transmission as well as for potentially blood/plasma donation (especially as paid donors). The aim of our study was to establish the profile of opiate addict and prevalence of blood-borne pathogens - Hepatitis B virus (HBV), Hepatitis C virus (HCV) and Human Immunodeficiency Virus (HIV) among 99 patients on substitution therapy with methadone and buprenorphine from Šumadia District. Methods: The Treatment Demand Indicator (TDI) of Pompidou-questionnaire was used to assess the history of drug abuse and risk behavior. All blood samples were tested for HBV surface antigen (HBsAg), anti-HCV antibody (anti-HCV) and HIV antigen/antibody (HIV-Ag/Ab) by Enzyme-Linked ImmunoSorbent Assay (ELISA) or Chemiluminescent Immuno-Assay (CIA). Investigations were also performed for HBV, HCV and HIV by molecular testing - Polymerase Chain Reaction (PCR) method. Results: The majority of patients were males (81.8%), median age 32 (19-57) years, lived in a city (99%), unemployed (58.6%), with finished secondary school (67.7%), unsafe injecting practices (34.3%) and never previously tested for HBV (39.4%), HCV (36.4%) nor HIV (28.3%); only 4% of them previously got HBV-vaccine. The complementary testing resulted with following results: HBV ELISA/CIA and PCR negativity for 66 patients and positive results (by ELISA/CIA and PCR) for 19 patients. However, a difference was observed in the ELISA/CIA-negative/PCR-positive result for 12 and ELISA/CIA-positive/PCR-negative for two patients respectively. Further, the negative results for HCV (ELISA/CIA and PCR testing) were found in 15 IDUs and positive results (using both methods) were found in 58 patients. Different results for ELISA/CIA-negative / PCR-positive results were found in 11 IDUs and ELISA/CIA-positive/PCR - negative results were found in 15 patients. All investigated IDUs were negative for HIV (ELISA/CIA and PCR testing) and for pathogens of opportunistic infection (Cryptococcus neoformans; Pneumocystis carinii; PCR testing), as well as for West Nile Virus (PCR testing). Just one IDU was positive for syphilis (ELISA and confirmatory testing). Conclusion: Our study demonstrated that the positivity for HBV and HCV is still very high (33.4% and 84.8%, respectively) in IDUs. Thus, we suggest that drug users have to be periodically screened using a complementary serological/molecular testing - concerning differences/discrepancies in the results obtained using these methods

Brownian fractal nature coronavirus motion

The goal of our research is to establish the direction of coronavirus chaotic motion to control corona dynamic by fractal nature analysis. These microorganisms attaching the different cells andorgans in the human body getting very dangerous because we don't have corona antivirus prevention and protection but also the unpredictable these viruses motion directions what resulting in very important distractions. Our idea is to develop the method and procedure to control the virus motion direction with the intention to prognose on which cells and organs could attach. We combined very rear coronavirus motion sub-microstructures images from worldwide experimental microstructure analysis. The problem of the recording this motion is from one point of view magnification, but the other side in resolution, because the virus size is minimum 10 times less than bacterizes. But all these images have been good data to resolve by time interval method and fractals, the points on the motiontrajectory. We successfully defined the diagrams on the way to establish control over Brownian chaotic motion as a bridge between chaotic disorder to control disorder. This opens a very new perspective to future research to get complete control of coronavirus cases

Antitumour effect of a mixture of n-propyl polysulfides In vitro

© 2019, University of Kragujevac, Faculty of Science. All rights reserved. Copper serves as a limiting factor for multiple steps of tumour progression, including angiogenesis, growth and metastasis. High levels of copper have been found in a wide spectrum of human cancers. Antitumour activities of copper-chelating drugs have been reported in animal models. Organosulfur compounds (diallyl sulfide, DAS; diallyl disulfide, DADS; S-ethylcysteine, SEC; N-acetylcysteine, NAC) derived from garlic exhibit marked copper-chelating activity. We analysed a mixture of fifteen n-propyl polysulfides (DPPS) for potential antitumour activity against several murine tumour cell lines, including colon carcinoma (CT26), mammary carcinoma (4T1) and melanoma cell lines (B16F10), and compared the effects with the antiproliferative effect in highly proliferative murine mesenchymal stem cells (mMSCs). The effects of the mixture of n-propyl polysulfides (100%) on cell viability were determined using MTT assays. Cell apoptosis was analysed using Annexin V-FITC/PI assays. The results of the MTT assays indicate that this standardized mixture of n-propyl polysulfides has a strong, dose-dependent cytotoxic effect against all three of the tested tumour cell lines (CT26, 4T1, B16F10). The cytotoxic effect of the n-propyl polysulfide mixture against the CT26 and B16F10 cell lines was much stronger than that of cisplatin and was significantly weaker in mMSCs, which are non-cancerous and highly proliferative cells, than in cancer cells. Flow cytometric analysis of CT26 and 4T1 cells revealed that apoptosis was not the dominant mechanism of cell death induced by the n-propyl polysulfide mixture. The n-propyl polysulfide mixture exerted highly cytotoxic activity against murine colon carcinoma and melanoma cell lines, but its antiproliferative activity against mMSCs was significantly lower than that of cisplatin

Article hepatoprotective effect of mixture of dipropyl polysulfides in concanavalin a-induced hepatitis

The main biologically active components of plants belonging to the genus Allium, responsible for their biological activities, including anti-inflammatory, antioxidant and immunomodulatory, are organosulfur compounds. The aim of this study was to synthetize the mixture of dipropyl polysul-fides (DPPS) and to test their biological activity in acute hepatitis. C57BL/6 mice were administered orally with DPPS 6 h before intravenous injection of Concanavalin A (ConA). Liver inflammation, necrosis and hepatocytes apoptosis were determined by histological analyses. Cytokines in liver tissue were determined by ELISA, expression of adhesive molecules and enzymes by RT PCR, while liver mononuclear cells were analyzed by flow cytometry. DPPS pretreatment significantly attenuated liver inflammation and injury, as evidenced by biochemical and histopathological observations. In DPPS-pretreated mice, messenger RNA levels of adhesion molecules and NADPH oxidase complex were significantly reduced, while the expression of SOD enzymes was enhanced. DPPS pretreatment decreased protein level of inflammatory cytokines and increased percentage of T regulatory cells in the livers of ConA mice. DPPS showed hepatoprotective effects in ConA-induced hepatitis, charac-terized by attenuation of inflammation and affection of Th17/Treg balance in favor of T regulatory cells and implicating potential therapeutic usage of DPPS mixture in inflammatory liver diseases

How many truths are there? Reconciliation and agonistic dialogue in the former Yugoslavia

In this paper, we offer a possible interpretation of reconciliation in the former Yugoslav area. In a conflicting past and not-reconciled region, it is presumed that the truth should be the main pillar of reconciliation. However, according to our empirical analysis of 146 reconciliation projects implemented in the period between 2002 and 2015, there are many interpretations of truths in the region which are opposed to each other. These interpretations are the result of different national political constructions, supported by the dominant structures of the societies in question. Accordingly, instead of insisting on a single factual truth, we propose the introduction of the 'agonistic dialogue' principle, where multiple truths would coexist, thus turning former war enemies into political adversaries in the post-conflict setting