A Mid-Infrared Imaging Survey of Embedded Young Stellar Objects in the Rho Ophiuchi Cloud Core

Results of a comprehensive, new, ground-based mid-infrared imaging survey of the young stellar population of the Rho Ophiuchi cloud are presented. Data were acquired at the Palomar 5-m and at the Keck 10-m telescopes with the MIRLIN and LWS instruments, at 0.25 arcsec and 0.25 arcsec resolutions, respectively. Of 172 survey objects, 85 were detected. Among the 22 multiple systems observed, 15 were resolved and their individual component fluxes determined. A plot of the frequency distribution of the detected objects with SED spectral slope shows that YSOs spend ~400,000 yr in the Flat Spectrum phase, clearing out their remnant infall envelopes. Mid-infrared variability is found among a significant fraction of the surveyed objects, and is found to occur for all SED classes with optically thick disks. Large-amplitude near-infrared variability, also found for all SED classes with optically thick disks, seems to occur with somewhat higher frequency at the earlier evolutionary stages. Although a general trend of mid-infrared excess and NIR veiling exists proceeding through SED classes, with Class I objects generally exhibiting K-veilings > 1, Flat Spectrum objects with K-veilings > 0.58, and Class III objects with K-veilings =0, Class II objects exhibit the widest range of K-band veiling values, 0-4.5. However, the highly variable value of veiling that a single source can exhibit in any of the SED classes in which active disk accretion can take place is striking, and is direct observational evidence for highly time-variable accretion activity in disks. Finally, by comparing mid-infrared vs. near-infrared excesses in a subsample with well-determined effective temperatures and extinction values, disk clearing mechanisms are explored. The results are consistent with disk clearing proceeding from the inside-out.Comment: 18 pages + 5 tables + 7 figure

BIOREMEDIATION OF SOILS CONTAMINATED WITH HEAVY METALS

Waste generated due to the growth of the modern industry is undergoing natural disposal in the environment for a long period of time. A special danger is caused by heavy metals that do not undergo biodegradation. Known purification methods of soils are not always effective and profitable. Correct selection of soil remediation methods contaminated with heavy metals ensures effective cleaning and restoration of soils. For this purpose, selecting representatives of various taxonomic groups of microorganisms binding heavy metals in the soil is carrying out. A complex method of purification of soils contaminated with have metals is being developed. Modified forms of humic acids were developed, geochemical barriers using local clays were created. Works to biostimulate local microorganisms required for bioremediation of soils contaminated with heavy metals are conducted. Remediation and increasing the fertility of soils contaminated with heavy metals are necessary for the prevention of further penetration of these metals into agricultural crops.Waste generated due to the growth of the modern industry is undergoing natural disposal in the environment for a long period of time. A special danger is caused by heavy metals that do not undergo biodegradation. Known purification methods of soils are not always effective and profitable. Correct selection of soil remediation methods contaminated with heavy metals ensures effective cleaning and restoration of soils. For this purpose, selecting representatives of various taxonomic groups of microorganisms binding heavy metals in the soil is carrying out. A complex method of purification of soils contaminated with have metals is being developed. Modified forms of humic acids were developed, geochemical barriers using local clays were created. Works to biostimulate local microorganisms required for bioremediation of soils contaminated with heavy metals are conducted. Remediation and increasing the fertility of soils contaminated with heavy metals are necessary for the prevention of further penetration of these metals into agricultural crops

Giant bleeding post-traumatic thoracic sarcoma management: A case report

The heterogeneity of thoracic wall tumors often represents challenging clinical entities for surgeons due to diagnostic and treatment complexities. The primary tumors, metastases, or direct invasion from intrathoracic structures comprise almost half of all cases on average that are proved to be malignant. Surgery treatment usually leaves large chest defects that require further extensive reconstruction and multimodal management including radiotherapy and chemotherapy. We report a rare case of a giant (30 cm) post-traumatic bleeding thoracic sarcoma treatment in a 70-year-old female. The use of our modified Verneuil technique to close the extensive postoperative skin defect optimized surgical wound management and provided good functional and aesthetic results. Four-year follow-up outcomes after surgical and adjuvant radiation therapy reported a high level of tumor control and showed no evidence of postoperative disease recurrence

Optical Spectroscopy of the Surface Population of the rho Ophiuchi Molecular Cloud: The First Wave of Star Formation

We present the results of optical spectroscopy of 139 stars obtained with the Hydra multi-object spectrograph. The objects extend over a 1.3 square degree area surrounding the main cloud of the rho Oph complex. The objects were selected from narrowband images to have H alpha in emission. Using the presence of strong H alpha emission, lithium absorption, location in the Hertzsprung-Russell diagram, or previously reported x-ray emission, we were able to identify 88 objects as young stars associated with the cloud. Strong H alpha emission was confirmed in 39 objects with line widths consistent with their origin in magnetospheric accretion columns. Two of the strongest emission-line objects are young, x-ray emitting brown dwarf candidates with M8 spectral types. Comparisons of the bolometric luminosities and effective temperatures with theoretical models suggest a medianage for this population of 2.1 Myr which is signifcantly older than the ages derived for objects in the cloud core. It appears that these stars formed contemporaneously with low mass stars in the Upper Scorpius subgroup, likely triggered by massive stars in the Upper-Centaurus subgroup.Comment: 35 pages of postscript which includes seven figures (some of which are multi-panel) and four postscript tables. Astronomical Journal (in press

A Search for Close Binaries in the Rho Ophiuchus Star-Forming Region

We have carried out a new, near-infrared speckle imaging survey of 19 members of the young stellar population in the nearby (d=140 pc), Rho Ophiuchi cloud core. Results for four binary and one newly discovered triple system are reported. Data for all known multiple systems among the pre-main-sequence population of Rho Oph are tabulated. We define a "restricted binary fraction", Fbr, and a "restricted companion fraction", Fcr, as counting only those systems most detectable in the present and previous high-resolution near-infrared imaging surveys, having separations between 0.1-1.1 arcsec and K-band magnitude differences, Delta K < 3. Analysis of all the available multiplicity data results in updated values of Fbr=Fcr=24%+/-11% for the Ophiuchus pre-main-sequence population. These values are consistent with the values in the Taurus star-forming region, and Fcr is in excess by a factor of 2 relative to the Main Sequence at the 1-sigma level.Comment: 21 pages, 6 figures, 4 table

MN112: a new Galactic candidate Luminous Blue Variable

We report the discovery of a new Galactic candidate Luminous Blue Variable (cLBV) via detection of an infrared circular nebula and follow-up spectroscopy of its central star. The nebula, MN112, is one of many dozens of circular nebulae detected at $24 \mu$m in the {\it Spitzer Space Telescope} archival data, whose morphology is similar to that of nebulae associated with known (c)LBVs and related evolved massive stars. Specifically, the core-halo morphology of MN112 bears a striking resemblance to the circumstellar nebula associated with the Galactic cLBV GAL 079.29+00.46, which suggests that both nebulae might have a similar origin and that the central star of MN112 is a LBV. The spectroscopy of the central star showed that its spectrum is almost identical to that of the bona fide LBV P Cygni, which also supports the LBV classification of the object. To further constrain the nature of MN112, we searched for signatures of possible high-amplitude (\ga 1 mag) photometric variability of the central star using archival and newly obtained photometric data covering a 45 year period. We found that the B magnitude of the star was constant ($\simeq$ 17.1$\pm$0.3 mag) over this period, while in the I band the star brightened by $\simeq 0.4$ mag during the last 17 years. Although the non-detection of large photometric variability leads us to use the prefix `candidate' in the classification of MN112, we remind that the long-term photometric stability is not unusual for genuine LBVs and that the brightness of P Cygni remains relatively stable during the last three centuries.Comment: 6 pages, 3 figures, accepted to MNRA

The Initial Mass Function and Disk Frequency of the Rho Ophiuchi Cloud: An Extinction-Limited Sample

We have completed an optical spectroscopic survey of an unbiased, extinction-limited sample of candidate young stars covering 1.3 square degrees of the Rho Ophiuchi star forming region. While infrared, X-ray, and optical surveys of the cloud have identified many young stellar objects (YSOs), these surveys are biased towards particular stages of stellar evolution and are not optimal for studies of the disk frequency and initial mass function.We have obtained over 300 optical spectra to help identify 135 association members based on the presence of H-alpha in emission, lithium absorption, X-ray emission, a mid-infrared excess, a common proper motion, reflection nebulosity, and/or extinction considerations. Spectral types along with R and I band photometry were used to derive effective temperatures and bolometric luminosities for association members to compare with theoretical tracks and isochrones for pre-main-sequence stars. An average age of 3.1 Myr is derived for this population which is intermediate between that of objects embedded in the cloud core of Rho Ophiuchi and low mass stars in the Upper Scorpius subgroup. Consistent with this age we find a circumstellar disk frequency of 27% plus or minus 5%. We also constructed an initial mass function for an extinction-limited sample of 123 YSOs (A_v less than or equal to 8 mag), which is consistent with the field star initial mass function for YSOs with masses > 0.2 M_sun. There may be a deficit of brown dwarfs but this result relies on completeness corrections and requires confirmation.Comment: 46 pages, 7 figures, 4 table

Can environment or allergy explain international variation in prevalence of wheeze in childhood?

Asthma prevalence in children varies substantially around the world, but the contribution of known risk factors to this international variation is uncertain. The International Study of Asthma and Allergies in Childhood (ISAAC) Phase Two studied 8–12 year old children in 30 centres worldwide with parent-completed symptom and risk factor questionnaires and aeroallergen skin prick testing. We used multilevel logistic regression modelling to investigate the effect of adjustment for individual and ecological risk factors on the between-centre variation in prevalence of recent wheeze. Adjustment for single individual-level risk factors changed the centre-level variation from a reduction of up to 8.4% (and 8.5% for atopy) to an increase of up to 6.8%. Modelling the 11 most influential environmental factors among all children simultaneously, the centre-level variation changed little overall (2.4% increase). Modelling only factors that decreased the variance, the 6 most influential factors (synthetic and feather quilt, mother’s smoking, heating stoves, dampness and foam pillows) in combination resulted in a 21% reduction in variance. Ecological (centre-level) risk factors generally explained higher proportions of the variation than did individual risk factors. Single environmental factors and aeroallergen sensitisation measured at the individual (child) level did not explain much of the between-centre variation in wheeze prevalence

DOES OSTEOPOROSIS AFFECT YOUNG MEN?

The title question explains the newly emerged tendencies of Osteoporosis and its prevalence. As the rates of the incidence of Osteoporosis are growing the myths related to the disease are about to crush. Many years doctors believed that women are much more likely to get osteoporosis than men, but IOF declared 2014 as the year of “Men osteoporosis” Moreover, if previously Osteoporosis was attributed to the conditions of an old age, today it is most apparent, scientists focused on Osteoporosis are evaluating the disease in young population; The information about Peak Bone Mass has a prognostic opportunity for the progression of the bone mass decrease and consequent bone fragility. The question in the article title line: Does Osteoporosis affect young men? the rationale of the question in the title lies in those risk-factors that determine development of OP are most likely uncovered in men rather than in women. Among them are: smoking, alcohol consumption, hypogonadal state. Androgens have vital role in bone formation in both: men and women. It is proved that osteoblasts have androgen receptors. Series of research support the evidence that androgen deficiency lead to retarded skeletal growth in men. Androgen Deficiency is recognized as the most potent reason of Bone Loss in Men. The aim of the study was to assess BMD in young Georgian men, and determine correlations between BMD and basic osteoporosis risk factors. 2800 Young Men with the age 22-50 (median age 38±4.6) years were examined, all patients have filled the questioner Table1 OP Risk-Factors in Young Georgian Males n=2800 Ge netic Factor Spine Defor mities Low Bone Mass <70 Alcohol con sump tion Hypo dynamic Lifestyle Low Cal cium Intake Sexual Potency De crease 15% 420 35% 980 10,7% 299,6 8,5% 238 21% 588 41% 1148 39,8% 1114,4 Bone Mass was measured using DXA Dual Energy Absorbtiometric Technique (Hologic 1000), according to T and Z criteria SD; in particular cases Lumbar Spine X-ray has been performed. Statistical Analysis was made by Excel-Windows Microsoft MedicalExe Statistical Software. Confidence indicators were calculated by the appropriate formula; Results have computed Normal Bone mass in 55% -2800 young men; Osteopenia in 17%; Osteoporosis (T<-2, 5 SD). Measured in 38% of the group. Results Received: 1. Low bone mass detected in 45% of Healthy Young Georgian Men ( more than 1000 men) Therefore, the condition should be followed to avoid progression of bone loss and its complications. 2. Secondary hypogonadotropic hypogonadism and Lumbar spine vertebral deformities were major OP risk -a factor is young Georgian men are: It is apparent that emerging risk-factors are continuing the list of worldwide recognized risk-factor; Consequently evaluation of newly-appearing risks should be spotted and closely monitored. 3. The correlation between Osteoporosis incidence and Hypogonadism is clear. It is recommended to correct hypogonadal state for the prevention of bone loss progression

DRUG USERS-RISK FACTOR OF OSTEOPOROSIS

Osteoporosis is one of the main problems in the world health care. Typical for osteoporosis is the progressive decrease of the bone mass, destruction of the bone micro-architectonics wich leads to increase the bone fragility, and a high frequency of the bone fractures. Osteoporosis was considered as pathology associated with gender. Up to recent times there was accepted that frequency of osteoporosis (OP) was higher in females. Though, during last few years the numerous research works and the result of our own work indicate that osteoporosis is quite frequent in males. And 2014 - was declared year of " Man's Osteoporosis". One of three patients with the fracture of femoral bone is a male morality among males in higher that among females. High frequency of incidence of the risk factors among males is confirmed. Though, actually, there are no works about frequency of osteoporosis in the people, who consume the drugs illegally. Taking into consideration the high rate of spreading of the drugs all over the world and especially, in our, region we set the goal of studying of the bone metabolism among the drug consumers, regarding the term, narcotization, character of the drugs and their doses. There were examined 911 patients with narcotism, in the absitence period; among which 462 patients were heroin consumers and 449 buprenorphine consumers; age of the patients from 17 to 25. Average duration of the heroin narcotism- 4.5 years and of average period of buprenorphine narcotism- 1.5 years. Among the risk factors of osteoporosis. Among the studied patients there were revealed: hypogonadism (71-80%); low calcium diet (72%); mallabsorption syndrome (64%); low body mass (78%). All patients underwent measurements of bone tissue mineral density, by dual X-ray vertebras of limbar region, procimalsec-tion of he femoral bone, in the distal section of the forearm. In all cases there was studied the Ca-P balance, level of osteocalcine in the blood and activity of the alkali-phosphatase; level of general and free testosterone in the blood. The research result showed that the frequency of revealing of osteoporosis (T<-2.5), among the patients with heroin narcotism is 40-48% and frequency of revealing in the trabecular bines is higher, Frequency of low characteristics of the bone tissue, in case of buprenorphine narcotism is lower and varies between 30-35%. There was revealed reliable decrease of calcium and testosterone levels in the blood (p<0.05) and decrease of the free testosterone level in patients with heroin narcotism. There was revealed correlation between the duration of narcotisation and level of free testosterone in the patients with heroin narcotism (z =-0.58;p<0.001), on one hand and on the other correlation the mineral density of the bone tissue and the level of free testosterone (r=0.42;p<0.001). There is considered the issue of possible impact of the drugs on the bone metabolism process. It is recommended, for treatment of patients with narcotism, to include anti-osteoporosis preparation into complex therapy