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A survey of about 100 lines of sight was made using the coudé auxiliary telescope and the coudé spectrograph of the Shane 3m telescope of the Lick Observatory. the data acquisition required 7 observing seasons. the spectra were recorded photographically at 17Ao/mm using a Varo tube intensifier. Each plate was separately calibrated for intensity and wavelength. the plates were measured using the PDS microdensitometer of the Royal Greenwich Observatory, Herstmonceux, and that data reduced on STARLINK using procedures developed by D.W.T. Baines. Care was taken to treat all photographic material in a consistent manner throughout the duration of the survey. the reduced data may therefore be considered self-consistent. the emulsion types used were (principally) Kodak IIIaF and (more rarely) 103aD.
Cover crops are known to promote many aspects of soil and water quality, yet estimates find that in 2012 only 2.3% of the total agricultural lands in the Midwestern USA were using cover crops. Focus groups were conducted across the Corn Belt state of Iowa to better understand how farmers confront barriers to cover crop adoption in highly intensive agricultural production systems. Although much prior research has focused on analyzing factors that help predict cover crop use on farms, there is limited research on how farmers navigate and overcome field-level (e.g. proper planting of a cover crop) and structural barriers (e.g. market forces) associated with the use of cover crops. The results from the analysis of these conversations suggest that there is a complex dialectical relationship between farmers' individual management decisions and the broader agricultural context in the region that constrains their decisions. Farmers in these focus groups shared how they navigate complex management decisions within a generally homogenized agricultural and economic landscape that makes cover crop integration challenging. Many who joined the focus groups have found ways to overcome barriers and successfully integrate cover crops into their cropping systems. This is illustrated through farmers' descriptions of their ‘whole system’ approach to cover crops management, where they described how they prioritize the success of their cover crops by focusing on multiple aspects of management, including changes they have made to nutrient application and modifications to equipment. These producers also engage with farmer networks to gain strategies for overcoming management challenges associated with cover crops. Although many participants had successfully planted cover crops, they tended to believe that greater economic incentives and/or more diverse crop and livestock markets would be needed to spur more widespread adoption of the practice. Our results further illustrate how structural and field-level barriers constrain individual actions, as it is not simply the basic agronomic considerations (such as seeding and terminating cover crops) that pose a challenge to their use, but also the broader economic and market drivers that exist in agriculturally intensive systems. Our study provides evidence that reducing structural barriers to adoption may be necessary to increase the use of this conservation practice to reduce environmental impacts associated with intensive agricultural production.
Astronomical fields under observation are being increasingly crossed by satellites. Such crossings either leave a “trail” on a photographic or CCD image, or corrupt a photographic observation. Such trailing/corruption may render an observation useless for scientific analysis. There is also the much more serious problem posed by suggestions to put solar reflectors in space for Earth illumination, artistic, celebratory or advertising purposes and, by extension, to longer term suggestions of ways to utilise dark time rather than twilight time. It is only a matter of time until the solar reflector becomes proven technology. The time left for decisive action may be very short.
The roles of the International Astronomical Union, the other ICSU Unions, UNESCO and the UN are reviewed in order to assess the way forward to resolve a unique situation - the impact of civilisation on the observational procedures of a particular science - astronomy. Action to create a modus vivendi to allow the continuance of vigorous astronomical science within a vibrant technological society is suggested.
The program has been continued thanks to the financial help of IAU, Unesco, and of local authorities. A school has been held in Lembang, Indonesia from May 16 to June 2, 1983, with students from India, Indonesia, Malaysia, Philippines, and Thailand. The Local Organizing Committee, chaired by B. Hidayat was very efficient, and the school is considered to be one of the most successful held to date. Both teachers and students expressed their appreciation to the School Secretary, Dr J. Kleczek, and to the IAU Executive Committee. Another school, foreseen in Venezuela for September 1983, had to be cancelled due to the lack of support of the Venezuelan Research Council. There are plans to hold several schools during the 1985-1988 period.
The Working Group often overlaps in responsibilities with other Commissions, particularly with Commission 46. Some projects (e.g. TAD) may begin on the initiative of our Group but are maintained by Commission 46. TAD programmes are now running in Viet Nam and Central America and one will begin soon in Morocco. Preliminary inquiries have been received from other countries.
Commission 46 is dedicated to Teaching of Astronomy. Commission 46 can be seen as an
extension of the IAU Executive Committee in the sense that each adhering country has
appointed a national representative to the Commission. National Representatives maintain
liaison between the Commission and the home country, and write national triennial reports
on development of astronomy on their nations. Other IAU astronomers, with special interest in education, can become regular individual members of the Commission. Non-IAU
members can be invited by the Commission to serve for one triennial term. Commission
46 considers that one of its major duties is to contribute to enhance astronomy education
in developing countries. The Newsletter, the International School for Young Astronomers,
the Visiting Lecturer Program and the Travelling Telescope are examples of such activities administered by the Commission. The strength of Commission 46 comes from the hard
work that its members do in order to promote astronomy education worldwide.
The chief activities of the Commission for this period were the organizing of two important meetings. The first was held as Joint Discussion 5 at the Kyoto General Assembly in August 1997. The proceedings have now appeared as “Preserving the Astronomical Windows”, edited by S. Isobe (1997).
At first sight, there may appear to be a very wide range of project situations that are in use. Students may seem to be doing the equivalent of postgraduate work, or may seem to be working on contract basis, or may even seem to be doing rather long term laboratory exercises, or some mixture of all three. However, there are in essence two major types of project situations — the free-scope project and the set-piece project.
The free-scope project attaches importance to the selection of project topics by the student. The student may be told to select a problem from the entire spectrum of problems offered by the science of astronomy, and to get on with it, or there may be guidelines to restrict the choice. Nevertheless, the choice of topic is the prerogative of the student, and it is believed that the effort of making that choice is important in the teaching/learning process. Because of the range of formats for free-scope projects, it is a convenient form to adapt to meet varying local circumstances.
Considerable attention has recently been given to the observation of interstellar molecules by radio methods. Interstellar molecules have also been given a boost because of excitation by the 3K black body radiation field (to use a convenient description). Nevertheless optical studies of interstellar lines have reached a very low ebb and, with brighter moments, have remained so since the work of Adams (1949).
The years 1937-1942 were the exciting period for optical studies of interstellar molecular lines. It is interesting to note that it was not molecular lines as such that led to the suspicion that molecules might exist in interstellar space but it was the discovery of the diffuse features at 5780, 5797, 6284 and 6614 by Merrill (1934) that led Russell (1935) to speculate on the possibility of their existence. It was Swings and Rosenfeld (1937) who stressed that likely interstellar molecules would be CH, OH, NH, CN and C2. Dunham, Adams and McKellar did much of the work of identifying interstellar lines in the period 1937-1940 and indeed McKellar (1941) had derived an excitation temperature of 2-3 K for CN - a value subsequently rediscovered.
The view that dust is essential to star formation is challenged on the ground that other interstellar constituents can provide more rapid cooling. From the evidence of stellar minimum masses it is suggested that self absorption of the radiation emitted by the coolant H2 is the dominant mechanism leading to the heating of a collapsing fragment. It is however shown that extensive dust and molecule formation may take place during star formation and that a natural explanation for the 4 terrestrial planets in the neighbourhood of the Sun is then provided.
(a)to develop astronomy through international cooperation;
(b)to promote the study and development of astronomy in all aspects;
(c)to further and safeguard the interests of astronomy.
The Union to carry out its mandate is organized into 11 Divisions representing major branches of astronomical activity. The Divisions are composed of specialist Commissions -out of 39 Commissions, 31 operate within the divisional structure: of the 8 Commissions which do not, 6 may be regarded as representing “Services”. Additionally there are 4 Working Groups of the Executive Committee. Table 1 lists the Divisions and their constituent Commissions.
In simulations of the collapse of gas clouds it is usual to start from a uniform sphere the evolution of which is determined by the two energy ratios = Thermal/Gravitational and = Rotational/Gravitational. In numerical calculations the two parameters are unfortunately supplemented by a number of unknown factors related to the exact numerical treatment of the collapse. It is therefore crucial to compare the results of several different methods before any judgement is made concerning the correct evolutionary track of the cloud.
We describe the cases of two children who both presented in infancy with recurrent severe pulmonary hypertensive crises. Exhaustive clinical work-up failed to identify an underlying aetiology. The patients had no clinical response to steroids, immunoglobulins, or pulmonary vasodilators. Post-mortem examination revealed extensive invasive pulmonary capillary haemangiomatosis. There was no evidence of pulmonary venous occlusive disease. Given the lethal nature of this condition, early consideration of referral to a lung transplant centre should be considered in selected patients.
In Navajo Nation v. U.S. Forest Service, 535 F.3d 1058 (9th Cir. 2008), cert. denied, 129 S. Ct. 2763 (2009), the Ninth Circuit seated en banc found that federal approval of a plan by a ski resort to make artificial snow with treated sewage effluent on Arizona's San Francisco Peaks, a mountain massif held sacred by the Navajo, Hopi, and four other claimant tribes, did not violate their religious liberty under the Religious Freedom Restoration Act (RFRA). The court accepted numerous factual findings about sincere religious exercise, but found federal approval of the scheme did not constitute a “substantial burden” on religion; rather, it only “decreased spiritual fulfillment” of tribal members. Despite a spirited dissent, the Ninth Circuit narrowly interpreted RFRA's language of “substantial burden” by making reference to the Supreme Court's 1988 holding in Lyng v. Northwest Cemetery Protective Association, 485 U.S. 439 (1988). This article shows how conventional wisdom about individualistic, subjective, and protean “spirituality” and in particular about “Native American spirituality” equips the court to denature highly specific and collective religious claims about the mountain by plaintiff tribes, and in turn to naturalize those claims as merely spiritual. Misrecognition of Native religions as Native spirituality then troubles the substantial burden analysis. While Navajo Nation suggests courts may never fully understand Native claims to sacred sites, the Supreme Court's 2014 holding in Burwell v. Hobby Lobby, Inc., 134 S. Ct. 2751, 2759 (2014), opens the door to revisiting the interpretive posture spelled out in Navajo Nation, and the Ninth Circuit's interpretive approach to “substantial burden” bears revisiting.