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PubMed2006

Intensification of the aerobic bioremediation of an actual site soil historically contaminated by polychlorinated biphenyls (PCBs) through bioaugmentation with a non acclimated, complex source of microorganisms.

BACKGROUND: The biotreatability of actual-site polychlorinated biphenyl (PCB)-contaminated soils is often limited by their poor content of autochthonous pollutant-degrading microorganisms. In such cases, inoculation might be the solution for a successful bioremediation. Some pure and mixed cultures of characterized PCB degrading bacteria have been tested to this purpose. However, several failures have been recorded mostly due to the inability of inoculated microbes to compete with autochthonous microflora and to face the toxicity and the scarcity of nutrients occurring in the contaminated biotope. Complex microbial systems, such as compost or sludge, normally consisting of a large variety of robust microorganisms and essential nutrients, would have better chances to succeed in colonizing degraded contaminated soils. However, such sources of microorganisms have been poorly applied in soil bioremediation and in particular in the biotreatment of soil with PCBs. Thus, in this study the effects of Enzyveba, i.e. a consortium of non-adapted microorganisms developed from composted material, on the slurry- and solid-phase aerobic bioremediation of an actual-site, aged PCB-contaminated soil were studied. RESULTS: A slow and only partial biodegradation of low-chlorinated biphenyls, along with a moderate depletion of initial soil ecotoxicity, were observed in the not-inoculated reactors. Enzyveba significantly increased the availability and the persistence of aerobic PCB- and chlorobenzoic acid-degrading cultivable bacteria in the bioreactors, in particular during the earlier phase of treatment. It also markedly enhanced PCB-biodegradation rate and extent (from 50 to 100%) as well as the final soil detoxification, in particular under slurry-phase conditions. Taken together, data obtained suggest that Enzyveba enhanced the biotreatability of the selected soil by providing exogenous bacteria and fungi able to remove inhibitory or toxic intermediates of PCB biodegradation and/or exogenous nutrients able to sustain microorganisms in charge for PCB mineralization. CONCLUSION: Enzyveba appears a promising agent for bioaugmenting actual-site PCB-polluted soils with a native low content of indigenous specialized microflora. This not only for its positive effects on the soil biotreatability but also for its availability on the market at a relatively low cost.

Journal Article↗
PubMed2026

Supplementation with effective microorganisms in earthen ponds affects common carp growth and abundance of specific bacterial families.

BACKGROUND: Effective microorganisms are increasingly explored in aquaculture to improve fish health and growth without leaving harmful residues. However, their efficacy in real-world pond environments remains poorly understood. Here, we conducted a 103-day field experiment to assess the effects of supplementation with two effective commercial microorganism products on the microbial communities and growth performance of common carp (Cyprinus carpio). BACKGROUND: Effective microorganisms were added to the feed and directly to the pond water. Microbial diversity was analysed via 16 S rRNA and whole-genome shotgun sequencing across three environments: water (three time points), sediment (two time points), and fish intestine (one time point) from 25 experimental ponds. Bioinformatics processing was performed using the QIIME2 and MG-TK pipelines with taxonomic classification based on the SILVA database. The results showed that although supplemented bacterial families did not establish significantly in pond environments, fish exposed to specific effective microorganism treatments showed improved growth metrics. CONCLUSIONS: These findings suggest that effective microorganisms can increase carp growth in aquaculture without significantly altering the resident microbial communities, suggesting a promising residue-free alternative to traditional additives in aquaculture.

Animals↗
PubMedDate not supplied

The performance of culture-based methods and microscopy for quantification of noninfectious airborne microorganisms in epidemiological studies of highly contaminated work environments.

Airborne levels of microorganisms traditionally have been measured by culture-based methods. Culture-based methods are suitable for the detection of infectious agents, but their suitability for the detection of microorganisms with toxic and allergic effects is less clear, because these effects do not depend on viability of the organisms. During the last 15 years several noncultural methods have been developed for the quantification of airborne microorganisms, including microscopic methods. Microscopy may be expected to provide more valid exposure estimates of microorganisms than culture-based methods, because live and dead microorganisms can be detected. However, their validity may also depend on the ability to differentiate between species. The literature was searched for epidemiological studies in which exposure-response analyses were carried out using culture-based methods and/or microscopy. The influence of several factors on exposure-response associations were considered: design; population size; analytical method; sampling method; exposure levels; outcome; and confounder adjustment. Thirteen studies were found, including a total of 49 exposure-response analyses, and 45% of the analyses showed associations. It was found that the potential of microscopic methods to uncover exposure-response associations was only marginally better than that of culture-based methods (47 and 44%, respectively). Exposure-response associations were more often found with fungi (70%) than with gram-negative bacteria (50%) or total bacteria (22%), perhaps because fungal exposure is more strongly associated to respiratory outcomes than exposure to bacteria. But the shortcomings of the measurement methods may also be important. Further development of measurement methods for bacteria is therefore needed. The complex composition of bioaerosols in many work environments necessitate the assessment of exposure to multiple agents and multivariate statistical analysis of exposure-response associations.

Air Pollution, Indoor↗
PubMed2006

Isolation of porphyran-degrading marine microorganisms from the surface of red alga, Porphyra yezoensis.

Marine microorganisms degrading porphyran (POR) were found on the surface of thalli of Porphyra yezoensis. Fifteen crude microorganism groups softened and liquefied the surface of agar-rich plate medium. Among these, 11 microorganism groups degraded porphyran that consisted of sulfated polysaccharide in Porphyra yezoensis. Following isolation, 7 POR-degradable microorganisms were isolated from the 11 POR-degradable microorganism groups.

Molecular Weight↗
PubMed2001

Toxicity of pesticides to aquatic microorganisms: a review.

Microorganisms contribute significantly to primary production, nutrient cycling, and decomposition in estuarine eco-systems; therefore, detrimental effects of pesticides on microbial species may have subsequent impacts on higher trophic levels. Pesticides may affect estuarine microorganisms via spills, runoff, and drift. Both the structure and the function of microbial communities may be impaired by pesticide toxicity. Pesticides may also be metabolized or bioaccumulated by microorganisms. Mechanisms of toxicity vary, depending on the type of pesticide and the microbial species exposed. Herbicides are generally most toxic to phototrophic microorganisms, exhibiting toxicity by disrupting photosynthesis. Atrazine is the most widely used and most extensively studied herbicide. Toxic effects of organophosphate and organochlorine insecticides on microbial species have also been demonstrated, although their mechanisms of toxicity in such nontarget species remain unclear. There is a great deal of variability in the toxicity of even a single pesticide among microbial species. When attempting to predict the toxicity of pesticides in estuarine ecosystems, effects of pesticide mixtures and interactions with nutrients should be considered. The toxicity of pesticides to aquatic microorganisms, especially bacteria and protozoa, is an area of research requiring further study.

Animals↗
PubMed1987

Post-prandial compositional changes of fluid- and particle-associated ruminal microorganisms.

Two ruminally cannulated cows were fed a diet containing 65% alfalfa haylage and 35% concentrate every 12 h. During two collection periods, whole ruminal contents were sampled before feeding, when feed not eaten was removed (1 h after initiation of feeding) and 1, 2, 3, 4, 6, 8, 10 and 12 h after removal. At each sampling, fluid-associated microorganisms were obtained by straining whole ruminal contents through eight layers of cheesecloth. A portion of the particle-associated population was obtained by chilling squeezed particles before seven successive extractions with saline solution. Microbial ash concentrations ranged from 9.9 to 16.6% of dry matter, with differences due to population (P less than .01) and to time after feeding for both fluid- (P less than .05) and particle-associated (P less than .01) microorganisms. Within 1 h after initiation of feeding, N decreased (P less than .05) from a pre-feeding concentration of 9.5% of organic matter to 7.7% for fluid-associated microorganisms, and from 9.2 to 6.7% for particle-associated microorganisms. Both populations did not return to pre-feeding concentrations until 6 h after feed removal. Nucleic acid concentrations decreased (P less than .05) in both populations after feeding, and did not return to pre-feeding concentrations until 6 h for fluid-associated and 4 h for particle-associated microorganisms. Nucleic acid-to-N ratios were higher (P less than .01) in the fluid- than particle-associated organisms.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2000

High pressure inactivation of microorganisms inoculated into ovine milk of different fat contents.

High hydrostatic pressure inactivation of Escherichia coli, Pseudomonas fluorescens, Listeria innocua, Staphylococcus aureus, and Lactobacillus helveticus were studied. These microorganisms were inoculated at a concentration between 10(7) and 10(8) cfu/ml in Ringer solution and in ovine milk adjusted to 0, 6, and 50% fat content to evaluate the baroprotective effect of fat content on inactivation of microorganisms. Treatments of pressurization consisted of combinations of pressure (100 to 500 MPa) and temperature (4, 25, and 50 degrees C) for 15 min. Gram-negative microorganisms were more sensitive than were Gram-positive ones (more destruction P. fluorescens > E. coli > or = List. innocua > Lb. helveticus > S. aureus). Pressurizations at low temperature (4 degrees C) produced greater inactivation on P. fluorescens, List. innocua, and Lb. helveticus than at room temperature (25 degrees C), whereas for E. coli and S. aureus the results were opposite. Ovine milk per se (0% fat) showed a baroprotective effect on all microorganisms, but percentage of fat (6 and 50%) did not show a progressive baroprotective effect in all pressurization conditions or for all microorganisms.

Animals↗
PubMed2000

Modeling UV-induced inactivation of microorganisms on surfaces.

A model is presented to account for inactivation by UV light of microorganisms on the surfaces of solid materials. In the model, the surface is divided into a discrete number of zones, each having a characteristic exposure factor (alpha). This is the ratio of UV intensity actually "seen" by the microorganism to that incident on the surface. Application of the model requires inactivation data obtained under conditions where the surface microorganisms are fully exposed to incident UV (alpha = 1) as well as kinetic inactivation data for the same microorganisms actually present on the surface of interest during UV irradiation. The kinetics in question may apply either to a single species or to the characteristic microflora associated with a particular material. Standard nonlinear programming techniques were used to determine the number of zones among which the microorganisms are distributed, the alpha for each zone, and the fraction of the microbial population present in each zone. The model was applied to data previously published by Gardner and Shama for UV inactivation of Bacillus subtilis spores on the surfaces of filter papers and also to the data of Stermer et al. for UV irradiation of beef. Good representation of the kinetics was obtained, and a maximum of three zones was required to adequately represent the experimental data. One direct application of the model is that it yields quantitative information about the UV fluences necessary to achieve specified reductions in microbial viability.

Animals↗
PubMed1999

[Relationships between air conditioning, airborne microorganisms and health].

Concurrently with the increase of air-conditioning, potentially severe or frequent new diseases have emerged, giving rise to social and economical consequences. The first part of this work is a state of the art review of the relationships between air-conditioning, airborne microorganisms and health, through a technical, metrological and medical approach. The second part presents four studies performed in this field. Two of them deal with the relationship between airborne microorganisms and technical features of air-conditioning. Measurements performed on actual sites demonstrated the benefit of using high efficiency filters and low risk components in air-conditioning systems. The third study was aimed to look for a relationship between airborne microorganisms and sick building syndrome symptoms. Statistical analyses of individual data revealed significant associations between airborne bacteria or fungi and symptoms. These results may be the first step in determining a dose-response relationship, in order to define threshold limit values in this field. In the fourth study, the contribution of particle counting in assessing exposure to airborne microorganisms was explored by monitoring simultaneous variations of microbial and particle concentrations. The results showed that associating particle counting may allow to detect microbial variations instantaneously, and therefore improve the assessment of exposure to airborne microorganisms.

Air Conditioning↗
PubMed1999

Relationships between activity of daily living, and oral cavity care and the number of oral cavity microorganisms in patients with cerebrovascular diseases.

We examined the relationships among the activity of daily living (ADL), oral cavity care, and the number of oral cavity microorganisms in 40 patients with cerebrovascular diseases (CVD). The CVD patients were classified into 4 groups, I, II, III and IV based on their ADL and the method used for oral cavity care. The ADL was highest in group I and lowest in group III. Only the patients of only group III could not eat by themselves and were receiving naso-esophageal feeding. Oral cavity care was performed by the patients themselves in groups I and IV, but was performed by caregivers in groups II and III. The group IV patients had no teeth, but could eat by themselves using full dentures. The numbers of microorganisms in the pharyngeal swabs from the 4 groups were measured and expressed as colony-forming units (cfu). The numbers of both Staphylococci spp. and Candida spp. were significantly higher in group III than in the other groups. Moreover, Pseudomonas aeruginosa was isolated only from patients of group III (in about 66%). The oral cavity care by caregivers was almost the same in groups II and III, but the numbers of oral cavity microorganisms were significantly higher in group III than in group II. These results indicated that microorganisms grow more easily in the oral cavities of CVD patients with low ADL compared with CVD patients with higher ADL, and that eating is thought to be important for the prevention of an increase of microorganisms in the oral cavity.

Activities of Daily Living↗
PubMed2000

Professional phagocytes: predators and prey of microorganisms.

Phagocytosis is an ancient cellular function. However, professional phagocytes have evolved only in higher organisms, where they play an important role in host defence. Professional phagocytes are capable of engulfing relatively large microorganisms and killing them with a combination of various microbicidal systems. Crucial killing mechanisms of phagocytes include superoxide generation by phagocyte NADPH oxidase and release of microbicidal proteins through exocytosis of performed granules. Phagocytes are also able to interfere with microbial growth through alteration of the phagosomal ionic environment (acidification, iron depletion). While the microbicidal mechanisms of phagocytes are extremely efficient and capable of killing most microorganisms, pathogenic microorganisms have developed mechanisms to resist phagocytes. Microorganisms capable of surviving within phagocytes are rare, but represent very successful pathogens, such as Mycobacterium tuberculosis. Other pathogens, such as S. aureus, have developed strategies to evade phagocytosis. How microorganisms are phagocytosed and killed, and why certain pathogens resist these mechanisms, are crucial questions for an understanding of the pathogenesis of infectious diseases and the development of innovative treatment approaches.

Humans↗
PubMed2000

Effects of three different infant dentifrices on biofilms and oral microorganisms.

The purpose of this work was to evaluate the effects of infant dentifrices: A--with lactoperoxidase, glucose oxidase and lactoferrin; B--with 1100 ppm of NaF and sodium lauryl sulfate; C--with extract of calendula. The dentifrices were test on biofilms formed in vitro from saliva and dental plaque of infants, using reference strains A. viscosus (ATCC 43146); C. albicans (ATCC 51501); L. casei (ATCC 4646); S. mitis (ATCC 49456); S. mutans (ATCC 25175); S. oralis (ATCC 35037); S. sanguis (ATCC 10586); S. sobrinus (ATCC 27609) and isolated clinically microorganisms C. albicans, S. mitis, S. mutans, S. oralis, S. sanguis, S. sobrinus and Lactobacillus sp. Twenty infants were chosen, who were beginning treatment at the Infants Clinic of the Pediatric Dentistry Department, Federal University of Rio de Janeiro. A pool of unstimulated saliva and a pool of dental plaque were collected from which biofilms were produced. Supernatants from each dentifrice were prepared and concentrated and diluted solutions of the dentifrices and a control sterile diluent were tested against the biofilms produced, for 1 and 3 minutes, and against the microorganisms. The results were statistically analyzed by the ANOVA and Tukey Test. After the exposure of the biofilms produced both from saliva and from dental plaque, to the dentifrice B concentrated and 1/2, for 1 and 3 minutes, the viable microorganisms count (CFU/ml), compared to the controls, was significantly reduced (p < 0.05). However, exposure to the dentifrices A and C concentrated and dentifrice B 1/4 and 1/8, for 1 and 3 minutes, was not significantly lethal to the biofilms. The dentifrices A and C, either concentrated or diluted (1/2 to 1/128) and the dentifrice B in the dilutions 1/16 to 1/128 did not have an antimicrobial effect on any microorganism evaluated. For all the microorganisms evaluated, the dentifrice B concentrated and in the 1/2 dilution showed a significant antimicrobial effect, when compared with the control (p < 0.05).

Actinomyces viscosus↗
PubMed2001

Real time biodetection of individual pathogenic microorganisms in food and water.

The primary objective of this research is to examine the feasibility of using an innovative technique based on laser-induced fluorescence coupled with flow cytometry to detect pathogenic microorganisms in food or water in real time. Our initial application is the rapid detection of E. coli O157:H7 in ground beef. The research performed demonstrated conclusively that this approach is feasible, and that the technique has key advantages over current alternatives including: it is (1) able to totally examine a large volume of food or water in real time, (2) capable of detecting single microorganisms (alternative techniques require in excess of 10(4) microorganisms), (3) intrinsically automatic, and (4) sensitive only to the selected bacteria. We have demonstrated the feasibility of detecting individual E. coli bacteria with a breadboard system. The performance of this system allows for rapid detection of individual specific pathogenic microorganisms. Two of the most significant commercial applications of this technique are the detection of infectious microorganisms in contaminated food and water. Food-borne microbial pathogens account for approximately 7 million illnesses and 9,000 deaths in the U.S. annually, with an estimated economic loss of at least $6 billion [1]. In addition, this method has the potential for a broad range of other commercial applications, including the detection of small numbers of molecules, such as the ultrasensitive detection of explosives and groundwater contaminants.

Animals↗
PubMed2001

Exposure to airborne microorganisms in Polish sawmills.

Microbiological air sampling was performed in four sawmills located in eastern Poland, of which two were processing coniferous wood (pine, fir) and other two deciduous wood (oak, birch). Total concentration of microorganisms (bacteria and fungi) in the air of sawmills processing coniferous wood was on average 20.2 +/- 5.6 x 10(3) cfu/m(3) (mean +/- S.E.) and significantly (p < 0.05) higher compared to those processing deciduous wood where the mean concentration of airborne microorganisms was 9.8 +/- 3.0 x 10(3) cfu/m(3). The greatest concentrations of microorganisms in the sawmills processing coniferous wood were noted at debarking and at first-cut frame sawing of pine logs (42.1 +/- 7.6 x 10(3) cfu/m(3) and 39.8 +/- 7.0 x 10(3) cfu/m(3), respectively). Microflora released into air during debarking consisted mostly of allergenic fungi (mainly Aspergillus fumigatus) and corynebacteria, whereas airborne microflora recovered during first-cut frame sawing constituted mostly of endotoxin-producing Gram- negative bacteria of the genus Rahnella, developing in the sapwood of pine. In the sawmills processing deciduous wood, the largest concentration of microorganisms (30.6 +/- 3.4 x 10(3) cfu/m(3)) was found at sorting of the oak parquet boards and was due to the secondary infection of the boards with moulds Penicillium citrinum during prolonged storing in the open air. Values of the respirable fraction of airborne microflora in the examined sawmills varied within fairly wide limits and were between 22.5 86.6%. Altogether, 34 species or genera of bacteria and 21 species or genera of fungi were identified in the air of sawmills, of which respectively 13 and 9 species or genera were reported as having allergenic and/or immunotoxic properties. The concentrations of airborne bacterial endotoxin which were determined on two sampling sites in the sawmills processing pine and fir, were 0.24 microg/m(3) and 4.00 microg/m(3) respectively, distinctly exceeding the suggested safe level. In conclusion, the workers of Polish sawmills may be exposed on some working stands to airborne microorganisms posing respiratory hazard, of which the greatest risk is represented by allergenic fungi developing on bark of logs or stored wood products and endotoxin-producing Gram-negative bacteria of the genus Rahnella, developing in sapwood of coniferous logs

Air Microbiology↗
PubMed2000

[Factors affecting colonization of introduced microorganisms on plant roots].

Microorganisms such as biological control agents (BCA), plant growth-promoting rhizobacteria (PGPR) and yield increasing bacteria (YIB) were introduced along growing roots. The colonization process of introduced bacteria was proved that they attached root tipfirst, then distributed along roots, multiplicated there, and survived as certain population size. The colonization location was closely related with root exudates, which was usually at the junction between cortex cells or at the base of lateral roots or root hairs. The variation of colonization by introduced microorganisms in the rhizosphere was caused by biotic and abiotic factors. Biotic factors included the physiological characters of introduced microorganisms and interactions between introduced microorganisms and native microbes. The more important factors were plant genotypes which associated with introduced beneficial microbes and regulated the population and community of those microbes affecting the colonization of introduced microorganisms. Abiotic factors here referred to soil environmental conditions, e.g., soil texture, water content, soil temperature and pH value.

Ecosystem↗
PubMed1964

Biological contamination of Mars. I. Survival of terrestrial microorganisms in simulated Martian environments.

It has been postulated that the accidental introduction of terrestrial microorganisms to other planets during the course of space exploration might impede or bias the detection of organic matter and possible indigenous organisms, and thereby confuse subsequent studies of extraterrestrial life. To assess the likelihood of biological contamination of Mars, we have applied the principle of natural selection on a laboratory scale. Terrestrial microorganisms were collected from a variety of environments, including regions of high alkalinity, low mean daily temperature, and low annual rainfall. The air-dried soils were then subjected to a simulated Martian environment involving 12-hour freeze-thaw cycles from about -60 degrees C to about +20 degrees C; atmospheres of 95 per cent nitrogen, 5 percent carbon dioxide and low moisture content: < or = 0.1 atm pressure; and a total ultraviolet dose at 2537 angstrom of 10(9) erg cm-2. In some experiments, organic supplements were provided. Survivors were scored on supplemented agar. Preliminary results indicate a wide variety of survivors, even when no organic supplements were introduced. Survivors included obligate and facultative anaerobic spore-formers and non-spore-forming facultative anaerobic bacteria. Diurnal freezing and thawing was continued for six months. There was no significant loss of viability after the first freeze-thaw cycle. An extensive literature survey shows that survival of terrestrial microorganisms under individual simulated Martian conditions has been known for decades. The present investigation shows the absence of pronounced synergistic effects inhibiting survival. The probable existence of organic matter and moisture on Mars, at least in restricted locales and times, makes it especially likely that terrestrial microorganisms can also reproduce on Mars. The demonstration that all samples of terrestrial soil tested contain a population of microorganisms which survive in simulated Martian environments strongly underscores the need for scrupulous sterilization of all spacecraft intended for Mars landing.

Bacillus subtilis↗
PubMed2002

Kinetics of polychlorinated biphenyl dechlorination by Hudson River, New York, USA, sediment microorganisms.

The kinetics of polychlorinated biphenyl (PCB) dechlorination by Hudson River (New York, USA) sediment microorganisms were investigated using Aroclor 1242 at 10 concentrations ranging from 0 to 900 ppm (0-11.2 micromol Cl/g sediment). The time course of PCB dechlorination and population growth were determined by congener-specific analysis and the most-probable-number technique, respectively, over a 44-week incubation period. Dechlorination rate (nmol Cl removed/g sediment/d) was a linear function of PCB concentrations similar to the dechlorination of Aroclor 1248 by sediment microorganisms from the St. Lawrence River (New York, USA). However, the rate was much slower, with the linear slope being only 24% that of the St. Lawrence River. The threshold concentration below which no dechlorination occurs was (mean +/- standard deviation) 1.06 +/- 0.18 micromol Cl/g sediment (85 +/- 14 ppm), threefold higher than that for the dechlorination of Aroclor 1248. The maximum extent of dechlorination was greater at higher Aroclor concentrations. Dechlorinating microorganisms did not show any significant growth until late in the lag phase of dechlorination, and their maximum was greater at higher initial Aroclor 1242 concentrations. Although dechlorination rates were significantly lower with the Hudson River inoculum, when normalized to the maximum number of dechlorinating organisms, they were not significantly different from those for Aroclor 1248 by St. Lawrence River microorganisms. These results further support the idea that PCB dechlorination is tightly linked to the growth of dechlorinating microorganisms.

Chlorine↗
PubMed1965

Response of microorganisms to a simulated Martian environment.

A study was undertaken to determine whether terrestrial microorganisms can survive in a simulated Martian environment. The ultimate objective is to establish whether earth organisms can contaminate Mars. In addition, any demonstration of survival and growth in a simulated Martian environment will provide information relating to the biology of Mars. In the experimental design, exhaustive consideration was given to the duplication of the known and the theoretical environmental parameters of Mars. These included composition of the soil and the atmosphere, barometric pressure, moisture content, solar radiation, and diurnal temperature extremes. Based upon these considerations, a simulated Martian summer environment was defined and used in the experiments. One group of microorganisms was selected from culture collections on the basis of their known characteristics. The other group was made of microorganisms isolated from soils. The soil samples were obtained from the Antarctic, from New Mexico, and California deserts, and from the Colorado tundra. The studies showed that a number of microorganisms can survive the simulated Martian environment. However, no substantial growth under such conditions could be demonstrated. The ability of microorganisms to form spores as a mechanism for survival will be discussed. Also, experiments utilizing augmented environments to establish minimum environmental conditions which will permit growth will be described.

Atmosphere↗