236 research outputs found
Remote and Normally Unpolluted High Mountain Lakes Provide Habitats with No or Very Limited Anthropogenic Influences and, Therefore, Their Hydrodynamics Are Mostly Regulated by the Natural Conditions. Researches in High Mountain Lakes Deal with Measuring
Remote and normally unpolluted high mountain lakes provide habitats with no or very limited anthropogenic influences and, therefore, their hydrodynamics are mostly regulated by the natural conditions. Researches in high mountain lakes deal with measuring and modeling the response of the habitats to environmental changes especially correlated to acid deposition, pollutants influx and climatic variability. The microbial world has also become a focus in many studies of these extreme ecosystems. Despite the pressure of harsh and extreme conditions, microbial communities living in these habitats developed flexible strategies and show quick adaptation to climate oscillation. New aspects in microbiological studies in recent high mountain lake research are presented in this paper
Bacterial Community Shifts of a High Mountain Lake in Response to Variable Simulated Conditions: Availability of Nutrients, Light and Oxygen
We studied bacterial population composition shifts by exposing natural water samples to variable simulated environmental conditions. The samples were taken from Lake Jori XIII (2640 m a.s.l), an oligo-to mesotrophic cold freshwater lake, located in the eastern Swiss Alps. The Jori lakes are characterized as remote, unpolluted high mountain lakes with a long period of ice cover and typically low nutrient concentrations. Culture independent techniques (PCR-based analyses) were used for detection and molecular characterization of a large number of bacteria most of which are still uncultivable. Bacterial community shifts over three ecological conditions (nutrients, light and oxygen availability) were detected by using Temporal Temperature gradient Gel Electrophoresis (TTGE) of a PCR-amplified part of the 16S rRNA gene. The bacterial populations responded differently to the variable conditions, as revealed by TTGE pattern shifts during the experiment
Можливості ефективної організації та стимулювання бажаних трансформацій
У статті розглядається поняття інформаційного впливу
як багаторівневого феномена. Вводиться розмежування між
інформаційними впливами під час взаємодії різних соціальних систем
і змальовано ефект інформаційного впливу на соціально-економічний
розвиток суспільства. У статті автор продовжує аналіз власної
концепції розвитку соціальних технологій постмодерного м’якого
управління з точки зору стану національної безпеки. Він розробляє
модель постмодерного інформаційного впливу – стимулювання
бажаних змін.The article examines the notion of information influence as a multilevel
phenomenon. The division is applied between information influence
of different social systems interaction and the impact of information
influence upon society’s social and economic development is shown. In
the article the author continues analysis of his conception of postmodern
soft management social technologies development from the point of view
of national security situation. He elaborates the model of postmodern
information influence – desirable changes stimulation
Results of Cultural Resources Survey for the Spring Lake Section 206 Aquatic Ecosystem Restoration Project, Texas State University-San Marcos, Hays County, Texas
The Center for Archaeological Studies (CAS) at Texas State University-San Marcos conducted intensive archaeological survey and subsurface testing investigations of the Area of Potential Effect (APE) of the Spring Lake Section 206 Aquatic Ecosystem Restoration Project (SLAERP). The SLAERP proposes to restore the aquatic ecosystem components of Spring Lake and riparian corridor/grassland habitat located directly adjacent to the lake to a more natural condition within the constraints of existing land uses. This work will be conducted under Section 206 of the Water Resources Development Act of 1996, which provides authority for the United States Army Corps of Engineers (USACE) to restore aquatic ecosystems. A Memorandum of Agreement (MOA) between the USACE, Texas State University-San Marcos (TxState), and the Texas Historical Commission (THC) regarding the Spring Lake Aquatic Restoration Project required CAS to develop and implement a subsurface testing program to determine the extent of intact cultural deposits within the project area. A testing program was developed and implemented by CAS that included both terrestrial and underwater investigations. Terrestrial investigations consisted of pedestrian survey, shovel test excavation, test unit excavation, auger pit excavation and backhoe trench excavation. Underwater investigations included limited reconnaissance survey, test unit excavation and the extraction of sediment cores. Investigations were conducted within or adjacent to State Archaeological Landmarks 41HY160 and 41HY165. Neither site was adequately delineated prior to this undertaking, and the work reported here results in modified site boundaries within the APE. New site boundaries demonstrate nearly continuous deposits across the APE, confirming that these sites actually represent a single extensive complex of archaeological deposits associated with the freshwater springs that presently form Spring Lake. Based on pending impacts as indicated in the 65 percent project design documents together with the results of the survey, six areas were identified as “Archaeologically Sensitive,” as they contained or possess a high probability to contain cultural deposits that would be negatively impacted by proposed demolition, modifications, and construction. Each of these archaeologically sensitive areas is linked with either 41HY160 or 41HY165, although, given the continuous nature of deposits in the APE, CAS concludes that distinctions between these trinomials are less meaningful than previously believed. CAS recommended the development of mitigation efforts to offset the loss of important information from these areas
Characterization, Comparative Genomics and Genome Mining for Antibiotics and Secondary Metabolite of two Actinomycetales isolates
Actinomycetes are ubiquitous Gram (+) bacteria commonly found to have high G+C content and best
known for their metabolic by-products and novel enzymes [1]. Isolates CCMMD2014 & MRMD2014
were co-cultured from soil impacted by a rusty fire hydrant in Woods Hole, MA. The Streptomyces sp.
and Curtobacterium sp. isolates were identified by marker genes for 16S rRNA, rpoB, xylose isomerase,
tryptophan synthase beta chain and Cytochrome P450 monooxygenase. Both isolates showed lactic acid
fermentation and urease activity. The co-isolates were separated by selective culturing with antibiotics.
In addition, whole genome sequencing revealed distinct inherent metabolic pathways in each culture
that allowed for mutually exclusive selective culture conditions. Assembly was done using HGAP3 with
Celera8 assembler using SMRT portal [2,3]. Annotation was done using the RAST server [4], with 7540
and 3969 CDS for Streptomyces sp. and Curtobacterium sp. respectively being revealed by AMIGene and
BASys [5,6]. Subsequently, antiSMASH [7], was used to predict 52 and 26 secondary metabolite
biosynthetic clusters that included genes for lantipeptides, terpenes, siderophores, polyketide synthases
type I and II, bacteriocin and nonribosomal peptide synthase genes for Streptomyces sp. and
Curtobacterium sp. respectively. The isolates have genes of potentially beneficial traits that could help
study, among others, the role of fimbrial adhesins and iron in biofilm formation and investigation on
natural products
Orbital apex syndrome caused by aspergilloma in an immunocompromised patient with cutaneous lymphoma: A case report of a rare entity
A 57-year-old man with a history of chemotherapy because of cutaneous lymphoma presented with an orbital apex syndrome. The cranial computed tomography scan revealed a tumour in the orbital apex, extending intradurally. With a suspected diagnosis of a neoplastic lesion, the patient underwent orbital surgery with optic nerve decompression. Histology revealed an aspergilloma. No other foci were seen and treatment with antifungals was started. In immunocompromised patients with intracranial tumours, infection is always a major consideration in the differential diagnosis, even if the reason for immunosuppression (in this case chemotherapy) dates back several months. Misdiagnosing an orbital apex lesion as a cancer and treating patients primarily with corticosteroids can be life threatening. Removal or biopsy of such lesions is essential in further treatment since antifungals have to be administered as fast as possible
The impact of adding low-dose leucovorin to monthly 5-fluorouracil in advanced colorectal carcinoma: Results of a phase III trial
Purpose A wide variety of fiuorouracil (FU)-plus-leucovorin (LV) dose schedules are in clinical use for the treatment of advanced colorectal cancer. Only the monthly low-dose LV-plus-FU regimen, as used by the North Central Cancer Treatment Group, has demonstrated a lasting survival benefit as opposed to FU alone (J Clin Oncol 1989; 7: 1407-1417). The Swiss Cancer Group adopted this regimen for a confirmatory phase III trial but used the same dose-intensity of fiuorouracil in both treatment arms. Patients and methods Patients with inoperable or metastatic colorectal cancer were randomized to receive monthly FU 400 mg/m2/day plus LV 20 mg/m2/day as intravenous push daily for five days, or FU alone. Results Three hundred nine of the 310 patients randomized were eligible and included in the analysis. The objective response rate for patients with measurable disease was 9% with FU alone and 22% with FU-plus-LV (P= 0.0001). The median progression-free survival was 3.9 versus 6.2 months (P = 0.003) and the overall survival 10 versus 12.4 months (P = 0.02). The major prognostic factors for survival were performance status, weight loss, and disease symptoms. WHO > 2 toxicity, consisting of stomatitis (P = 0.001), diarrhea (P=0.001), and nausea (P), = 0.001), was more pronounced for FU-plus-LV, without fatal events. Conclusions This is the largest published randomized trial to compare FU-plus-LV to FU alone in advanced colorectal cancer. It confirms the survival benefit obtained from biomo-dulating monthly FU with low-dose LV. The toxic effects of FU-plus-LV were acceptable to most patients, and they responded well to FU dose reductions. In the absence of an ideal dose-intense FU monotherapy regimen, monthly FU with low-dose LV provides a simple and economical means by which to achieve adequate FU efficacy in the treatment of advanced colorectal cance
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Does intensive forest management affect innate immunity of wild deer mice (Peromyscus maniculatus)?
To examine the influence of forest management on wildlife immunity, the innate immune system of wild deer mice (Peromyscus maniculatus) inhabiting forest plots of different management intensities in the Oregon coast range was measured by bactericidal assay. Bactericidal activity was compared across three management levels, including 40-50 year old forest stands without recent intervention, areas clear-cut within the past 12 months but not managed further, and finally, plots clear-cut within the past 12 months that were also intensively treated with herbicides. Our results show a trend whereby bactericidal activity increases with management intensity, indicating that innate immunity in animals inhabiting more disturbed environments is better or upregulated. Although unexpected, this pattern may result from stress associated with poor habitat quality and could ultimately could change the dynamics of pathogens harbored in these communities
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