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Fg 1 (He 2–66) is a southern planetary nebula that presents an elliptical shape. Deep CCD imaging and long-slit spectroscopy have been obtained at Las Campanas Observatory of this object. The images were obtained in the light of Hα+[NII], [SII] λλ6716,6731, HeII λ4686 and in the broad-band Rgunn filter. The spectra were obtained oriented N-S, P.A. 90°, and P.A. 85°. The instrumental combination yields a spectral resolution of ∼ 2 Å FWHM, covering a spectral range ≃ λλ 6290–6805 Å.
He 2-119 is a bright, elliptical, planetary nebula of relatively large size (117 arcsec along the major axis and 74 arcsec along the minor one). Digital, unsharp masking CCD imaging of this object is presented, revealing a filamentary, nearly bipolar inner structure. In addition, the discovery of an extended, faint halo in this object is reported. The halo has a diameter of 208 arcsec and has a nearly circular form. He 2-119 thus becomes a new member of the group of planetary nebulae with halos. Its general characteristics are discussed.
GM24 is a small visible nebulosity in the vicinity of a molecular cloud. In this contribution we present the results of continuum (6-cm) and CO line (J = 1 → 0) radio observations, infrared maps, broad-band photometry and low-resolution spectroscopy as well as long-slit Echelle Ha spectroscopy. We found evidence that the GM24 = PP85 nebula is part of a larger region where star formation occurred in the past 104 years; the region is embedded in a typical molecular cloud with a dimension of ∼ 10 pc and mass of ∼104 M⊙. A compact radio H II region seems to be associated with GM24 and with one of the mid-infrared peaks detected. The nebula is most probably the visible part of an embedded H II region that is starting to emerge from the cloud. The other infrared peaks found in its vicinity (∼ 1 pc) are probably associated with less evolved stellar objects. The complex also shows an extended near-infrared flux which we believe to arise in a reflection nebula. From energy arguments, we found that the luminosity required to power the H II region and keep the cloud at the observed large temperature (TK ≅33 K), is ∼105 L⊙ which is consistent with the infrared total flux from the present measurements and those from IRAS of 4x104 L⊙; this corresponds to the flux of ∼3 BO ZAMS stars. The details of the present work have appeared in the Revista Mexicana de Astronomía y Astrofísica, Volume 11, 83, 1985.
A short-term Jolly–Seber mark-recapture model experiment is described. This experiment was aimed at estimating the rate of catch per unit effort (CPUE) and the catchability coefficient (q) of the Atlantic blue crab (Callinectes sapidus) in the fishing port of Sisal, Yucatan, Mexico. To estimate the local population size, 52 traps were deployed along four transects located in a coastal capture area of 3600 m−2. The CPUE and q were compared between the daily mark-recapture Jolly–Seber experiment and the bi-monthly (carried out every 2 months) samplings. The average abundance was estimated at 3475 individuals. All three suggested scenarios, applied to estimate densities, gave similar estimates, i.e. 0.0386, 0.0350, 0.0365 crabs m−2 for the first (Previously Cited Attraction Radius), second (CPUE per transect) and third (Catchability-Density Relationship), respectively. Based on the latter scenario, densities ranged from 27,900 (annual average) to 36,500 (Spring) crabs km−2. The average CPUE of the daily mark-recapture experiment was estimated at 1.96 crabs trap−1, whereas the average bi-monthly CPUE was estimated at 1.13 crabs trap−1. The q (per trap) was estimated at 0.0186 for the daily mark-recapture experiment and at 0.0247 for the bi-monthly sampling. Both catchability and CPUE increased in individuals whose size ranged between 110 and 170 mm CW. However, no significant difference (ANCOVAs) was found between the daily and bi-monthly samplings neither in CPUE nor in catchability. The use of both mark-recapture data and the Jolly–Seber model proved to be a fast and reliable method for estimating the abundance and catchability of Atlantic blue crab.
Cosmopolitan pests such as Brevicoryne brassicae, Lipaphis pseudobrassicae, and Myzus persicae (Aphididae) cause significant damage to Brassicaceae crops. Assessment of the important biotic and abiotic factors that regulate these pests is an essential step in the development of effective Integrated Pest Management programs for these aphids. This study evaluated the influence of leaf position, precipitation, temperature, and parasitism on populations of L. pseudobrassicae, M. persicae, and B. brassicae in collard greens fields in the Triângulo Mineiro region (Minas Gerais state), Brazil. Similar numbers of B. brassicae were found on all parts of the collard green plants, whereas M. persicae and L. pseudobrassicae were found in greatest numbers on the middle and lower parts of the plant. While temperature and precipitation were positively related to aphid population size, their effects were not accumulative, as indicated by a negative interaction term. Although Diaeretiella rapae was the main parasitoid of these aphids, hyperparasitism was dominant; the main hyperparasitoid species recovered from plant samples was Alloxysta fuscicornis. Parasitoids seem to have similar distributions on plants as their hosts. These results may help predict aphid outbreaks and gives clues for specific intra-plant locations when searching for and monitoring aphid populations.
The aim of this study is to compare the corrosion rate of aluminum alloys for ornamental pieces. Three Fe/Cu relationships were tested in order to improve hardness and brightness in aluminum pieces since these alloys are used in the making of ornamental pieces. The variation on Fe/Cu content could result in modification on corrosion rate, since a metallographic characterization must be carried out identifying the presence of intermetallic phases. The presence of these elements could result in increasing corrosion rate, or even in modification of corrosion morphology, so localized corrosion could be expected.
The assessment of corrosion rate was carried out in saline media, since chlorides are ions that promote localized corrosion. Electrochemical techniques (polarization curves and Tafel plots) were used in order to evaluate the attack in aluminum pieces; electrochemical impedance spectroscopy was also employed with voltage amplitude of 10 mV rms, and a frequency range from 10,000 Hz to 0.01 Hz. A typical three electrodes cell was used, exposing an area of one cm2. Before polarization, open circuit potential was monitored for an hour looking for a steady state. All conditions were tested for triplicate.
The behavior of open circuit potential vs. time, and polarization curves was analyzed; a corrosion mechanism is proposed according to the electrochemical control. Polarization rate was calculated by using Tafel plots and, an electrochemical impedance spectroscopy analysis by using equivalent electric circuits is shown. Electrochemical impedance will yield information about corrosion morphology that is backed with microscopic inspection.
The objective of this study is to compare the corrosion rate of aluminum alloys for ornamental pieces in order to determine the effect of the relationship Fe/Cu on the corrosion mechanism in aluminum parts for ornamental pieces.
Glioblastoma (GBM) is the most common brain cancer. Resistance to front-line systemic therapy with temozolomide (TMZ) is correlated with O6-methylguanine-DNA-methyltransferase (MGMT) expression. Second-line treatment with bevacizumab has not improved overall survival. Dianhydrogalactitol (VAL-083) is a bi-functional alkylating agent that has MGMT-independent cell-kill activity against GBM cell-lines and cancer stem cells in vitro. VAL-083 crosses the blood-brain barrier and showed promise against CNS tumors in prior NCI-sponsored clinical trials. The goal of this clinical trial is to determine appropriate VAL-083 dosing for advancement to Phase III trials as a new treatment for recurrent GBM. METHODS: Patients must have recurrent GBM following surgery, radiation, TMZ and bevacizumab. Phase I: Open-label, single-arm, dose-escalation study. Patients received VAL-083 on days 1,2,3 of a 21-day cycle, until reaching MTD. Phase II: Additional patients enrolled at MTD to further assess safety and outcomes. RESULTS: Phase I: 29 patients were enrolled across 9 dose cohorts (1.5-50 mg/m2/d). 40mg/m2/d was confirmed as MTD. Myelosuppression was mild; no drug-related serious adverse events were reported at doses up to 40mg/m2/d. Dose limiting G4 thrombocytopenia was observed at higher doses. Platelet nadir occurred around day 20 and resolved rapidly and spontaneously. A dose-related survival improvement was observed. Pharmacokinetic analyses show 1-2h plasma terminal half-life; average Cmax 781ng/mL at 40mg/m2/d. Phase II: 14 patients were enrolled at 40mg/m2/d. To date, safety observations in Phase II are consistent with Phase I. CONCLUSIONS: VAL-083 at 40mg/m2/d exhibits a favorable safety profile and dose-related trend toward clinically meaningful improved survival in refractory GBM patient
Glioblastoma (GBM) is the most common brain cancer. Most GBM tumors have unmethylated promoter status for O6-methylguanine-DNA-methyltransferase (MGMT); a validated biomarker for MGMT protein-expression and ensuing temozolomide-resistance. Second-line treatment with bevacizumab has not improved overall survival (OS). Dianhydrogalactitol (VAL-083) is a bi-functional alkylating agent targeting N7-Guanine, thus MGMT-independently inducing interstrand cross-links, DNA double-strand breaks and cell-death in GBM cell-lines and cancer stem cells. VAL-083 is currently in Phase I/II clinical trial for recurrent GBM, post-TMZ and post-bevacizumab. In this Phase II clinical trial, the main goal is to assess the 9-month OS in MGMT-unmethylated, recurrent, bevacizumab-naive GBM. RATIONALE: The vast majority of GBM patients experience recurrent/progressive disease within a year from initial diagnosis and median survival after recurrence is 3-9 months. Chemotherapy regimens for these patients are lacking and there is a significant unmet medical need. Given VAL-083’s novel alkylating mechanism, promising clinical benefit, and favorable safety profile, a trial studying VAL-083 in MGMT-unmethylated recurrent GBM is warranted. METHOD: Randomized, non-comparative biomarker-driven Phase II clinical trial in MGMT-unmethylated GBM patients at first recurrence/progression, prior to bevacizumab. 48 patients will be randomized to receive VAL-083 or “standard-of-care” salvage drug lomustine. 32 patients will receive VAL-083 40mg/m2/day on days 1,2,3 of a 21-day cycle. 16 patients will receive lomustine 90 mg/m2/day on day 1 of a 42-day cycle. Patients will be followed until death or for at least 9 months from enrollment, whichever occurs earlier. Survival will be compared to the BELOB trial for recurrent MGMT-unmethylated GBM patients treated with lomustine.
To evaluate the influence of rate of gestational weight gain on newborn birthweight and birthlength in twin gestations complicated by preeclampsia, 74 cases of preeclampsia in twin pregnancy were matched to 148 non-preeclamptic twin controls for maternal race, height, pregravid weight, age and length of gestation. Total weight gain was significantly higher for all cases versus controls and for mild cases versus controls. However, the rate of early weight gain was lower for severe cases and severe cases with thrombocytopenia compared to their controls. Mean birthweight and birthlength did not differ between cases and controls, although the proportion with birthlength below the 10th percentile was significantly higher among cases than controls. In addition, the proportion of birthweights and birthlengths < 10th percentile was significantly higher among cases than controls. These findings suggest that inadequate early weight gain in twin gestations complicated by preeclampsia results in retarded birthlength and birthweight. The implication of these findings are discussed.
The Southern Proper Motion Program (SPM) is described and progress in the execution of the second-epoch is outlined, as are the reduction methods. Recent changes in the instrumentation, including the addition of a computer control room to the astrograph building and the construction and operation of a new survey machine are discussed.
The presence of high-velocity, collimated outflows in planetary nebulae (PNe) has been observationaly established in recent years. Furthermore, these collimated outflows, or jets, are usually found to be symmetric with respect to the nucleus. In some cases, their morphology and spatial distribution indicates episodic outbursts and rotation of the symmetry axis. In these cases, the bipolar, rotating, episodic jets are identified as BRETs. The existence of bipolar jets in PNe has been considered perplexing since the mechanisms for their formation are unclear. However, substantial progress in their study has been made in the last few years, from both theoretical and observational grounds. Consequently, new results in the field are rapidly coming out, as it can be noticed from the number of related works in this symposium. We still need to reach solid answers in many aspects of this field, but its influence in the study of PNe has already modified the traditional views of PNe shaping and evolution. The main characteristics of some of these phenomena are discussed here, together with prototypical cases, including a compilation of PNe with BRETs charateristics.
Long-slit optical spectroscopy and VLA-B radio continuum (λ = 3.6 cm) observations toward the compact planetary nebulae Cn 3-1 and M 3-27 are presented. Optical spectra were taken at different position angles (PAs) with the 2.2 m telescope at Calar Alto (Spain), covering the range from 6549 to 6751 Å. The radio and optical data show that the ionized shell of Cn 3-1 is an ellipsoid (size ≃ 6″ × 5″, PA ≃ 72°) containing a bright ring-like equatorial zone (size ≃ 2″.6, expansion velocity ≃ 14 km s–1) and two bright point-symmetric arcs, extending from the equator towards the polar regions of the ellipsoid (Fig. 1). These arcs seem to be filamentary structures embedded in the ellipsoid. An ionized stellar wind has been detected through faint extended wings in the Hα (≃ 660 km s–1) and [N II] (≃ 460 km s–1) emission lines. M 3-27 is unresolved at 3.6 cm (size ≤ 0″6). The detected [N II] and [S II] emission lines arise in a compact (≤ 1″4) probably non-spherical region which is identified with the ionized shell of M 3-27. The Hα emission from M 3-27 is dominated by strong emission from an ionized stellar wind and exhibits a Type III P Cygni profile with very extended wings (≃ 3000 km s–1). The estimated kinematic age and ionized mass of Cn 3-1 (≃ 1300 yr, 4 × 10–2 M⊙) and M 3-27 (≤ 530 yr, ≃ 3 × 10–4 M⊙) indicate that both objects are young planetary nebulae. Extended halos (size ≃ 36″ in Cn 3-1, ≃ 24″ in M 3-27) have been spectroscopically detected in both objects. An analysis of the kinematic and emission properties shows that both halos are reflection nebulosities and suggests that the distribution of neutral material in them probably is largely isotropic. The results suggest that the halos correspond to isotropic mass ejections occurred in the last ≃ 2 × 104 yr of the AGB phase of the Cn 3-1 and M 3-27 progenitors.
The present triennial commission report embraces mainly activities in wide angle, optical astrometry. With the successful development and application of new techniques from Earth (e.g. optical interferometry, CCD’s) and space (Hipparcos mission and new projects) the sub-division between Commissions 8 (Positional Astrometry) and 24 (Photographic Astrometry) has become questionable. During the GA at Kyoto in 1997 all steps for a merger of both commissions have been taken. The final merging will take place at the forthcoming GA in Manchester. For a more complete overview on astrometrical work done in the past triennium the reader should also take notice of the report of Commission 24.