Histogram Reweighting Method for Dynamic Properties

The histogram reweighting technique, widely used to analyze Monte Carlo data, is shown to be applicable to dynamic properties obtained from Molecular Dynamics simulations. The theory presented here is based on the fact that the correlation functions in systems in thermodynamic equilibrium are averages over initial conditions of functions of the trajectory of the system in phase-space, the latter depending on the volume, the total number of particles and the classical Hamiltonian. Thus, the well-known histogram reweighting method can almost straightforwardly be applied to reconstruct the probability distribution of initial states at different thermodynamic conditions, without extra computational effort. Correlation functions and transport coefficients are obtained with this method from few simulation data sets.Comment: 4 pages, 3 figure

Prevalence of antimicrobial resistance in bacteria isolated from central nervous system specimens as reported by U.S. hospital laboratories from 2000 to 2002

BACKGROUND: Bacterial infections of the central nervous system, especially acute infections such as bacterial meningitis require immediate, invariably empiric antibiotic therapy. The widespread emergence of resistance among bacterial species is a cause for concern. Current antibacterial susceptibility data among central nervous system (CNS) pathogens is important to define current prevalence of resistance. METHODS: Antimicrobial susceptibility of pathogens isolated from CNS specimens was analyzed using The Surveillance Database (TSN(®)) USA Database which gathers routine antibiotic susceptibility data from >300 US hospital laboratories. A total of 6029 organisms derived from CNS specimen sources during 2000–2002, were isolated and susceptibility tested. RESULTS: Staphylococcus aureus (23.7%) and Streptococcus pneumoniae (11.0%) were the most common gram-positive pathogens. Gram-negative species comprised approximately 25% of isolates. The modal patient age was 1 or <1 year for most organisms. Prevalence of MRSA among S. aureus from cerebrospinal fluid (CSF) and brain abscesses were 29.9–32.9%. Penicillin resistance rates were 16.6% for S. pneumoniae, 5.3% for viridans group streptococci, and 0% for S. agalactiae. For CSF isolates, ceftriaxone resistance was S. pneumoniae (3.5%), E. coli (0.6%), Klebsiella pneumoniae (2.8%), Serratia marcescens (5.6%), Enterobacter cloacae (25.0%), Haemophilus influenzae (0%). Listeria monocytogenes and N. meningitidis are not routinely susceptibility tested. CONCLUSIONS: Resistance is commonly detected, albeit still at relatively low levels for key drugs classes such as third-generation cephalosporins. This data demonstrates the need to consider predominant resistance phenotypes when choosing empiric therapies to treat CNS infections

Emerging resistance among bacterial pathogens in the intensive care unit – a European and North American Surveillance study (2000–2002)

Background Globally ICUs are encountering emergence and spread of antibiotic-resistant pathogens and for some pathogens there are few therapeutic options available. Methods Antibiotic in vitro susceptibility data of predominant ICU pathogens during 2000–2 were analyzed using data from The Surveillance Network (TSN) Databases in Europe (France, Germany and Italy), Canada, and the United States (US). Results Oxacillin resistance rates among Staphylococcus aureus isolates ranged from 19.7% to 59.4%. Penicillin resistance rates among Streptococcus pneumoniae varied from 2.0% in Germany to as high as 20.2% in the US; however, ceftriaxone resistance rates were comparably lower, ranging from 0% in Germany to 3.4% in Italy. Vancomycin resistance rates among Enterococcus faecalis were ≤ 4.5%; however, among Enterococcus faecium vancomycin resistance rates were more frequent ranging from 0.8% in France to 76.3% in the United States. Putative rates of extended-spectrum β-lactamase (ESBL) production among Enterobacteriaceae were low, \u3c6% among Escherichia coli in the five countries studied. Ceftriaxone resistance rates were generally lower than or similar to piperacillin-tazobactam for most of the Enterobacteriaceae species examined. Fluoroquinolone resistance rates were generally higher for E. coli (6.5% – 13.9%), Proteus mirabilis (0–34.7%), and Morganella morganii (1.6–20.7%) than other Enterobacteriaceae spp (1.5–21.3%). P. aeruginosa demonstrated marked variation in β-lactam resistance rates among countries. Imipenem was the most active compound tested against Acinetobacter spp., based on resistance rates. Conclusion There was a wide distribution in resistance patterns among the five countries. Compared with other countries, Italy showed the highest resistance rates to all the organisms with the exception of Enterococcus spp., which were highest in the US. This data highlights the differences in resistance encountered in intensive care units in Europe and North America and the need to determine current local resistance patterns by which to guide empiric antimicrobial therapy for intensive care infections

The sovereign debt crisis: the impact on the intermediation model of Italian banks

The aim of the contribute is to analyze the impact of the financial crisis, in particular since the start of the sovereign debt phase, on Italian banks and their intermediation model. Italian banks\u2019 specific business model explains why they suffered less than those of other countries during the first phase of the crisis, requiring one of the lowest levels of public facilities in the EC as compared to GDP. Most of these same characteristics have changed from positive to negative factors since the sovereign debt crisis, which hit Italy hard, affecting first banks\u2019 liquidity and secondly the cost and volumes of funding and loans. Italian banks are now facing the effects of the double-dip recession, which has significantly weakened businesses and households, their key customer segments, and their borrowing and saving capability, with an increasing rate of non-performing loans. This situation is impairing the sustainability of the \u201ctraditional\u201d intermediation model and means that banks must introduce strategies for significantly modifying the banking business model they adopt

Prevalence and antimicrobial susceptibilities of bacteria isolated from blood cultures of hospitalized patients in the United States in 2002

BACKGROUND: Bloodstream infections are associated with significant patient morbidity and mortality. Antimicrobial susceptibility patterns should guide the choice of empiric antimicrobial regimens for patients with bacteremia. METHODS: From January to December of 2002, 82,569 bacterial blood culture isolates were reported to The Surveillance Network (TSN) Database-USA by 268 laboratories. Susceptibility to relevant antibiotic compounds was analyzed using National Committee for Clinical Laboratory Standards guidelines. RESULTS: Coagulase-negative staphylococci (42.0%), Staphylococcus aureus (16.5%), Enterococcus faecalis (8.3%), Escherichia coli (7.2%), Klebsiella pneumoniae (3.6%), and Enterococcus faecium (3.5%) were the most frequently isolated bacteria from blood cultures, collectively accounting for >80% of isolates. In vitro susceptibility to expanded-spectrum β-lactams such as ceftriaxone were high for oxacillin-susceptible coagulase-negative staphylococci (98.7%), oxacillin-susceptible S. aureus (99.8%), E. coli (97.3%), K. pneumoniae (93.3%), and Streptococcus pneumoniae (97.2%). Susceptibilities to fluoroquinolones were variable for K. pneumoniae (90.3–91.4%), E. coli (86.0–86.7%), oxacillin-susceptible S. aureus (84.0–89.4%), oxacillin-susceptible coagulase-negative staphylococci (72.7–82.7%), E. faecalis (52.1%), and E. faecium (11.3%). Combinations of antimicrobials are often prescribed as empiric therapy for bacteremia. Susceptibilities of all blood culture isolates to one or both agents in combinations of ceftriaxone, ceftazdime, cefepime, piperacillin-tazobactam or ciprofloxacin plus gentamicin were consistent (range, 74.8–76.3%) but lower than similar β-lactam or ciprofloxacin combinations with vancomycin (range, 93.5–96.6%). CONCLUSION: Ongoing surveillance for antimicrobial susceptibility remains essential, and will enhance efforts to identify resistance and attempt to limit its spread

Tracking the implementation of NCCLS M100-S12 expanded-spectrum cephalosporin MIC breakpoints for nonmeningeal isolates of Streptococcus pneumoniae by clinical laboratories in the United States during 2002 and 2003

BACKGROUND: The Performance Standards for Antimicrobial Susceptibility Testing, Twelfth Informational Supplement, M100-S12, published by the National Committee for Clinical Laboratory Standards (NCCLS) in January 2002 introduced distinct minimum inhibitory concentration (MIC) interpretative breakpoints for ceftriaxone, cefotaxime, and cefepime for nonmeningeal isolates of Streptococcus pneumoniae. Previously, a single set of interpretative breakpoints was used for both meningeal and nonmeningeal isolates. METHODS: To estimate the rate of adoption of the M100-S12 interpretive breakpoints by clinical laboratories, antimicrobial susceptibility test results for ceftriaxone and cefotaxime from nonmeningeal S. pneumoniae isolates were studied using data collected from January 2002 to June 2003 by The Surveillance Network(® )Database – USA (TSN(®)), an electronic surveillance database. RESULTS: Of the 262 laboratories that provided data that could be evaluated, 67.6% had adopted the M100-S12 breakpoints one and one-half years after they were published. CONCLUSIONS: The NCCLS M100-S12 recommendation to interpret MICs to expanded-spectrum cephalosporins using two distinct sets of breakpoints for meningeal and nonmeningeal isolates of S. pneumoniae was steadily implemented by clinical microbiology laboratories in the United States following their initial publication in January 2002. The use of these new breakpoints more accurately reflects the clinical activities of expanded-spectrum cephalosporins than did the single set of interpretative breakpoints previously used for both meningeal and nonmeningeal isolates

Polypeptides from Hermetia illucens: a bio source for innovative materials in the framework of a circular economy model

Plastic waste reduction is one of the main challenges of the 21st century from an environmental and sustainability perspective. Still nowadays, relatively little plastic waste is collected for recycling (less than 10%) and a large fraction (approximately 20%) of Municipal Solid Waste (MSW) goes to landfill. At the global level, the generation of municipal solid waste (MSW) is estimated to be 2.5 billion tonnes per year, of which 30-55% is represented by the so-called organic fraction of municipal solid waste (OFMSW). While the use of alternative, plastic-like materials from natural sources could be one of the most appealing solutions, the massive occupation of agricultural soils for their supply is a big concern. In this scenario, waste valorization is gaining major relevance within the framework of circular economy models, with bio-conversion mediated from insects being one possible and effective answer. The project RICH (Turning Rubbish Into biobased materials: a sustainable CHain for the full valorization of organic waste) aims to develop an innovative and integrated circular economy chain, which, starting from the biotransformation of the organic fraction of municipal solid waste (OFMSW), allows the targeted production of biobased materials with high technological value, such as bioplastics and other advanced protein-based materials. In the present study, proteins and polypeptides were extracted from larvae of Hermetia illucens, also known as black soldier fly. Extracts were characterized by means of proteomics techniques such as BCA, SDSPAGE, and LC-MS analyses. Procedures were next defined to prepare materials such as films, tuning the mechanical properties, and investigating the correlation with the molecular structure. Elastic films were obtained and the elasticity was correlated with the chemical composition and the protocol for film preparation. The results so far obtained pave the way for the application of these materials in the biomedical and packaging fields, bringing us closer to the completion of a new circular economy model

Innovative bioplastics from polypeptides of Hermetia illucens

The environmentally sustainable waste management, together with waste valorization, is one of the actual challenges pursued by the European Commission. UE policies are thus contributing in the frameworks of circular economy by promoting the extraction of high quality materials from wastes. At the European level, the generation of municipal solid waste (MSW) is estimated to be 500 kg per capita, of which 70% (discarded food, yard trimmings, paper and wood) is represented by the so-called organic fraction of municipal solid waste (OFMSW). In this scenario, organic waste valorization is gaining major relevance within circular economy models, with bioconversion mediated from insects being one possible and effective answer to the problem. The project RICH (Turning Rubbish Into biobased materials: a sustainable CHain for the full valorization of organic waste) aims to develop an innovative and integrated circular economy chain, which, starting from the biotransformation of the organic fraction of municipal solid waste (OFMSW), allows the targeted production of biobased materials with high technological value, such as bioplastics and other advanced protein-based materials. In the present study, proteins and polypeptides were extracted from larvae and pupae of Hermetia illucens, also known as Black Soldier Fly. The extraction efficiency from both stages was assessed. Crude extracts were characterized by means of proteomics techniques such as BCA, SDS-PAGE, and LC-MS analyses. State of art materials were prepared, investigating the correlation with the molecular structure through physical techniques (FTIR, Contact Angle, TGA). Results clearly points out a correlation between film-forming ability and the chosen larval stage, with extracts from Larvae at the 6th instar leading to the best results. A correlation with polypeptide chain length is proposed

The transmission of unconventional monetary policy to bank credit supply : evidence from the TLTRO

We assess the transmission of the Targeted Longer-Term Refinancing Operations (TLTRO) to the bank credit supply for the Euro area (2014:05-2018:01) and for Portugal (2011:01-2018:01), using a panel data setup. For the Euro area, we find a positive relationship between the TLTRO and the amount of credit granted to the real economy. For the vulnerable countries, the effects of the TLTRO on the stock of credit increased from 2016 to 2017. Among the group of small banks, the effects are stronger in less vulnerable countries. We also find that competition has no statistically significant impact on the transmission of the TLTRO to the bank credit supply for the Euro area. For Portugal, using a difference-in-differences model, we find no statistically significant impact of the TLTRO on credit granted by banks. Finally, bidding banks set lower interest rates than non-bidding banks and the difference seems to be larger in 2017. In Portugal, the effects of the TLTRO on loan interest rates also increased from 2016 to 2017 and are stronger for small banks.info:eu-repo/semantics/publishedVersio