Spectral Signatures of Submicron Scale Light-Absorbing Impurities in Snow and Ice Using Hyperspectral Microscopy

Light-absorbing impurities (LAI) can darken snow and ice surfaces, reduce snow/ice albedo and accelerate melt. Efforts to allocate the relative contribution of different LAI to snow/ice albedo reductions have been limited by uncertainties in the optical properties of LAI. We developed a new method to measure LAI spectral reflectance at the submicron scale by modifying a Hyperspectral Imaging Microscope Spectrometer (HIMS). We present the instrument’s internal calibration, and the overall small influence of a particle’s orientation on its measured reflectance spectrum. We validated this new method through the comparison with a field spectroradiometer by measuring different standard materials. Measurements with HIMS at the submicron scale and the bulk measurements of the same standard materials with the field pectroradiometer are in good agreement with an average deviation between the spectra of 3.2% for the 400–1000 nm wavelength range. The new method was used (1) to identify BC (black carbon), mineral dust including hematite and the humic substances present in an environmental sample from Plaine Morte glacier and (2) to collect the individual reflectance spectra of each of these types of impurity. The results indicate that this method is applicable to heterogeneous samples such as the LAI found in snow and ice

Antibiotic resistance and antibiotic consumption with focus on Escherichia coli and Pseudomonas aeruginosa

Aims: The general aims of the present studies were to assess the levels of antibiotic resistance, in relation to antibiotic consumption at the Karolinska University Hospital, Solna (KS) and at 11 other Swedish hospitals, furthermore to assess the role of the membrane protein OprD and penicillin-binding proteins in Pseudomonas aeruginosa resistance to imipenem. Methods: Resistance figures were retrieved from the microbiology service databases for the period 1989-99, at the 12 above mentioned hospitals, including their intensive care units (ICU). Antibiotic consumption figures were obtained from the National Corporation of Swedish Pharmacies database during the same period. In order to study molecular mechanisms of carbapenem resistance, we produced transconjugants from clinical isolates of carbapenem resistant P. aeruginosa in a sensitive PAO18 after selection for a proline marker (proB). The active sites of penicillin-binding proteins PBP1b, PBP2, PBP3 and PBP6 were sequenced, and the expression of oprD, pbp2 and pbp3 genes was measured using quantitative real-time PCR. Results: Resistance to ciprofloxacin increased in Escherichia coli and P. aeruginosa in parallel with an increased quinolone consumption in all included hospitals. The use of cephalosporins increased two and a half times, while the level of resistance in E. coli to cefuroxime and cefotaxime remained stable at KS. A third pattern was observed for co-trimoxazole resistance in E. coli, which increased at KS as well as the other 11 Swedish hospitals, while consumption of co-trimoxazole and trimethoprim decreased during the 12 year study period. Resistance rates at KS were still generally low, but there were increasing trends for some antibtiotic-microbe combinations. E. coli resistance to ciprofloxacin increased from 0% in 1991 to 11% in 1999 and co-trimoxazole resistance increased in E. coli from 7.5% to 14% during the study period. For E. coli, resistance to ciprofloxacin was higher at the hospital than at the ICUs. There were considerable fluctuations in resistance prevalence over time, especially at the ICU. Imipenem resistance in P. aeruginosa was particularly noticeable at the ICU, with resistance peaks of 15% and 28% in 1992 and 1999, respectively. These peaks were due to outbreaks. Sequencing of P. aeruginosa genes for PBP1b, PBP2, PBP3 and PBP6 showed no differences in amino acid sequence, but the gene for OprD porin was downregulated in all imipenem resistant clinical strains and their transconjugants. Conclusions: The significant trend of increased resistance to antibiotics over time constitutes an important warning system. The relation between antibiotic consumption and antibiotic resistance was not always parallel. Three different patterns were observed which suggests that different mechanisms were operating. We also found in some cases, higher resistance rates at the hospital than at the ICUs emphasizing the importance of including all sectors of a hospital. Also, antibiotic resistance figures fluctuated substantially over time, illustrating the value of long surveillance periods. Finally, in imipenem resistant P. aeruginosa, a previously unknown gene for regulation of oprD, is most likely located close to the proB marker

Whole genome sequencing of extended-spectrum β-lactamase producing Klebsiella pneumoniae isolated from a patient in Lebanon.

ObjectiveThe emergence of extended-spectrum β-lactamase (ESBL)-producing bacteria is now a critical concern. The ESBL-producing Klebsiella pneumoniae constitutes one of the most common multidrug-resistant (MDR) groups of gram-negative bacteria involved in nosocomial infections worldwide. In this study we report on the molecular characterization through whole genome sequencing of an ESBL-producing K. pneumoniae strain, LAU-KP1, isolated from a stool sample from a patient admitted for a gastrointestinal procedure/surgery at the Lebanese Amrican University Medical Center-Rizk Hospital (LAUMCRH) in Lebanon.MethodsIllumina paired-end libraries were prepared and sequenced, which resulted in 4,220,969 high-quality reads. All sequence processing and assembly were performed using the A5 assembly pipeline.ResultsThe initial assembly produced 86 contigs, for which no scaffolding was obtained. The final collection of contigs was submitted to GenBank. The final draft genome sequence consists of a combined 5,632,663 bases with 57% G+C content. Automated annotation was performed using the RAST annotation server. Sequencing analysis revealed that the isolate harbored different β-lactamase genes, including bla oxa-1, bla CTX-M-15, bla SHV-11, and bla TEM-1b. The isolate was also characterized by the concomitant presence of other resistance determinants most notably acc(6')-lb-cr and qnrb1. The entire plasmid content was also investigated and revealed homology with four major plasmids pKPN-IT, pBS512_2, pRSF1010_SL1344, and pKPN3.ConclusionsThe potential role of K. pneumonia as a reservoir for ESBL genes and other resistance determinants is along with the presence of key factors that favor the spread of antimicrobial resistance a clear cause of concern and the problem that Carbapenem-non-susceptible ESBL isolates are posing in hospitals should be reconsidered through systematic exploration and molecular characterization

Draft Genome Sequences of Extended-Spectrum -Lactamase-Producing Escherichia coli Strains Isolated from Patients in Lebanon

We present the draft genome sequences of nine extended-spectrum β-lactamase (ESBL)-producing Escherichia coli strains isolated from stool samples collected from patients admitted for gastrointestinal and urological procedures/surgeries. An average of 3,889,300 paired-end reads per sample were generated, which assembled in 77 to 157 contigs

Diálogos no Feminino. Antologia Poética Maria Pawlikowska-Jasnorzewska – Florbela Espanca / Dialogi kobiece. Antologia Poezji Maria Pawlikowska-Jasnorzewska – Florbela Espanca

De acordo com as últimas tendências do comparativismo europeu (que responde à urgência da Europa contemporânea em aproximar os seus pontos opostos através do encontro e conhecimento) organizamos uma antologia poética das obras das escritoras Florbela Espanca (1984-1930) e Maria Pawlikowska-Jasnorzewska (1981-1945), notando um diálogo com temáticas muito parecidas dessas mulheres pioneiras nas letras europeias do começo do século XX que, efetivamente, mantêm entre si uma sintonia no “feminino”. Ou seja, as poetisas encarnam uma voz poética com uma força reivindicadora patente através de um rigor formal e sensualidade ousada, como marcas identitárias de quebra de paradigmas e de resistência à situação de alienação da mulher. Elas firmam-se, assim, como precursoras na luta pelos direitos de acesso à representação do prazer erótico na literatura (algo negado e condenado dentro de sociedades que se erigiram sob a bandeira da moral judaico-cristã) e não apenas, já que as autoras surgem dentro de um contexto literário – tanto em Portugal, quanto na Polónia dentro de um certo anacronismo no feminismo – contra o panorama dessa “mesmice”, resultado da pacífica submissão da mulher aos modelos socioculturais que a sociedade lhe impunha. Tais poemas estão carregados de sinestesias que servem de dispositivo à expressão sensual e não apenas: os discursos presentes nas obras destas mulheres escritoras revelam a forma de uma prática social, um modo de acção, moldados a partir de uma visão de mundo que até então era permitida apenas a vozes masculinas, demonstrando uma certa face feminista, como assim se refere Elzbieta Hurnikowa (2000) sobre a poetisa Maria Pawlikowska-Jasnorzewska, identidade essa que também faz parte da poetisa portuguesa. Por isso, Florbela e Maria articulam, entre outros tantos enfoques, a relação entre o corpo e a escrita, porque na metáfora da escrita a mulher participaria demonstrando sua própria formainfo:eu-repo/semantics/publishedVersio