1,368 research outputs found
Thin film thermoelectric devices as thermal control coatings: A study
Peltier effect, Thomson effect, and Seeback effect are utilized in design of thermal control coating that serves as versatile means for controlling heat absorbed and radiated by surface. Coatings may be useful in extreme temperature environment enclosures or as heat shields
The Block Beautification Project: Three Years Later
This article provides an update to the 2017 piece, Community Based Project: The Block Beautification Project: One Artist’s Work to Help Make West Baltimore Beautiful, sharing the status of the West Baltimore art installations three years later
INFORMATION TECHNOLOGY AND ECONOMIC REORGANIZATION
Information Technology (IT) can support or even cause changes in the structure of industries and the relationships between firms. Yet, at present, we lack the vocabulary and theory to explain or predict these changes. Drawing on recent work in the resource-based theory of the firm, we propose that shifts in resource values are central to economic restructuring. We show how IT can operate to shift resource values through the basic economic drivers of network externalities and economies of scale, scope, and specialization. We use this theory to investigate the situations that will lead to each of the basic structural responses: changes in market consolidation, in diversification, and in vertical integration. We also can make some specific statements about what forms can be employed in the structural responses: ownership, outsourcing, or cooperation
Surveillance of environmental fungi, with focus on Aspergillus, in a Portuguese Central Hospital.
Objectives: Because immunocompromised patients are more prone to acquire nosocomial infections caused by fungi isolated from the environment, e.g. Aspergillus, this study aimed to screen the hospital environment for the presence of fungi and to understand their epidemiology in the different hospital wards analyzed.
Methods: During one-year period, four seasonal samplings, i.e., air and hard surface, were performed. A total of 101 air samples and 99 surface samples were collected from the Hematology, Oncology, and Intensive Care Unit (ICU) wards of a Portuguese Central Hospital. Aspergillus isolates were plated for growth as single colonies on malt extract agar with chloramphenicol to check the colony purity and observe colonial morphology. The universal fungal primers ITS1 and ITS4 were used to amplify DNA from all Aspergillus isolates, amplimers were sequenced, and isolates identified to the species-complex level. Statistical analyses were done using SPSS v15.0 program for Windows.
Results: Aspergillus was the most frequently recovered fungal genus (20.9%), followed by Cladosporium (18.7%), and Penicillium (17.2%). Thirty-five Aspergillus isolates were collected from the wards with hematological patients (bone marrow transplant and hemato-oncology wards), whereas 15 isolates were recovered from ICU. Among Aspergillus isolates from the hospital environment, those belonging to the species-complexes of versicolores (n = 26; 32.5%), nigri (n = 12; 15.0%), flavi (n = 11; 13.7%), and circumdati (n = 6; 7.5%) dominated. Hemato-Oncology was the ward with higher fungal counts, whereas the bone marrow transplant ward, which is protected by HEPA-filtration of the supply air, showed the lowest numbers in all sampling periods. A significant association (p = 0.001) was found between the season and the Aspergillus complexes isolated, with spring and summer having a larger number of different species-complexes detected in the hospital´s air and on the surfaces. Nevertheless, air counts showed that the autumn was the season with the highest proportion of Aspergillus (one third of the total number of fungi detected). This could be due in part to the presence of construction work near these wards.
Conclusion: The knowledge of the epidemiology of environmental fungi in each hospital may allow the establishment of preventive or corrective measures to decrease nosocomial fungal infections
Screening of cryptic species among clinical Aspergillus isolates collected during one year period in a Portuguese reference laboratory
Objectives: Correct identification of Aspergillus species is important given that sibling species may show variable susceptibilities to multiple antifungal drugs and also because sharper definition of species may facilitate epidemiological studies. Thus, we screened Aspergillus clinical isolates from Portuguese hospitals to determine which, if any, of the cryptic species of Aspergillus were involved in patient infections.
Methods: Over a one year period, Aspergillus isolates from Portuguese health institutions were collected. These isolates were identified on the basis of microscopic morphology and through the use of molecular tools. Genomic DNA was prepared from each isolate and the sequencing of the Internal Transcribed Spacers (ITS) regions, specifically the ITS1 and ITS2 non-coding regions flanking the 5.8S rDNA was used to determine the species complex, whereas β-tubulin and calmodulin sequencing was done to achieve the correct species identification.
Results: Over the study period, 57 Aspergillus isolates from clinical samples were collected from 10 Portuguese health institutions. According to the morphological observations, 29 isolates were identified as Aspergillus fumigatus, 11 A. flavus, 8 A. niger, 3 A. nidulans, 2 A. terreus, 2 A. candidus and 2 Aspergillus sp. Among those isolates, six species-complexes were detected by ITS sequencing, and were distributed as follows: fumigati (50.1%), flavi (21.0%), nigri (15.8%), terrei (5.3%), nidulantes (3.6%) and versicolores (3.6%). β-tubulin and calmodulin sequencing resulted in ten (17.5%) cryptic species being identified among the 57 isolates. Six of those isolates belonged to the nigri complex (A. brasiliensis, A. awamorii and A. tubigensis), two to the versicolores complex (A. sidowii and A. fructus), one to the fumigati complex (A. lentulus) and one to the nidulantes complex (Emmericella echinulata).
Conclusion: With rigorous application of molecular tools, cryptic species of Aspergillus are not uncommon in the clinic. The identification of cryptic species among the collected clinical isolates of Aspergillus alerts the clinician to isolates with reduced susceptibilities to antifungal drugs and emphasizes a correct identification to species level
Identification of Aspergillus cryptic species in hospital environment
Selected hospital wards, housing patients at higher risk to develop invasive fungal infections, were screened in order to understand the epidemiology and distribution of Aspergillus, especially regarding the presence of cryptic species.Aspergillus species were identified by b-tubulin and calmodulin sequencing, and a high percentage of cryptic species (i.e., not sensu stricto) was found (59%). Sections Usti, Versicolores and Circumdati harbored the highest proportion of cryptic species [100% (4/4), 95% (19/20) and 90% (9/10),
respectively].The high number of cryptic species found raises concerns about the possible reduced susceptibility to antifungals of hospital environmental Aspergillus isolates. These data reinforce the
importance of hospital air and surface monitoring, mainly in immunocompromised patients’ wards
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