ABSTRACTDiffraction gratings are famously associated with Henry Rowland of Johns Hopkins University but there were precursors. Although gratings were first made and used in Europe, reliable machines for ruling gratings were developed in the USA, and two men, Lewis Rutherfurd and William Rogers, tackled the problem before Rowland. Rutherfurd, a wealthy independent astronomer, designed and built the first screw-operated engine for ruling diffraction gratings, the fore-runner of almost all subsequent ruling engines. With it he and his assistant D. C. (...) class='Hi'>Chapman ruled many gratings which he generously distributed to practising scientists, thereby materially advancing the science of spectroscopy. Rogers was a Harvard astronomer who developed an interest in the ruling of fine lines on glass that led him to construct a ruling engine with which he investigated the causes of the errors in the rulings he had examined. He continued to seek improvements with a second engine designed for ruling diffraction gratings. He ceased developing this engine when Rowland’s excellent gratings began to be available, concentrating instead on related problems to which he could apply the knowledge and skills he had gained, but his investigations assisted Rowland and other later ruling engine builders. This paper brings together what is known about the ruling engines of Rutherfurd and Rogers, their development, the gratings they produced, their quality and the work that was done with them, and assesses and compares their achievements and the impacts of the work of these two men. (shrink)

Pain is not a primitive sensory event but rather a complexperception and a process by which a person interacts with theinternal and external environments, constructs meaning, andengages in action. Because folk beliefs are central to meaning,folk concepts of pain play multiple causal roles in a painpatient's interaction with health care providers and others.In every case, the notion of pain is linked to a goal-directedbehavior that is useful to the person. The wide variation inconcepts of pain across individuals suffering with painunderscores (...) the richness and complexity of the pain experience.In some cases involving chronic pain, the patient may form amaladaptive cluster of behaviors around the concept of pain.Patient beliefs and expectations are an important part of manychronic pain syndromes, and patients can benefit fromintervention directed at revising the individual's folk model of pain. Memetics offers a framework for identifying the memesthat patients hold and determining whether patient memes fitor clash with provider memes. (shrink)

In matters of rights, constitutions tend to avoid settling controversies. With few exceptions, rights are formulated in open-ended language, seeking consensus on an abstraction without purporting to resolve the many moral-political questions implicated by rights. The resulting view has been that rights extend everywhere but are everywhere infringed by legislation seeking to resolve the very moral-political questions the constitution seeks to avoid. The Negotiable Constitution challenges this view. Arguing that underspecified rights call for greater specification, Grégoire C. N. Webber draws (...) on limitation clauses common to most bills of rights to develop a new understanding of the relationship between rights and legislation. The legislature is situated as a key constitutional actor tasked with completing the specification of constitutional rights. In turn, because the constitutional project is incomplete with regards to rights, it is open to being re-negotiated by legislation struggling with the very moral-political questions left underdetermined at the constitutional level. (shrink)

Transsexualism, a condition in which from earliest recollection the individual is unshakeably convinced he or she has been endowed with the wrong physical sexual body presents one of the most difficult problems as regards management and treatment in clinical medicine. The aetiology and treatment is discussed and the problems with which the medical practitioner may be faced in advising his transsexual patient which include change in social role and marriage and the difference between sex and gender.

A major problem in developing an effective gene therapy for the nervous system lies in understanding the principles that maintain or turn off the expression of genes following their transfer into the CNS.

ABSTRACT During a visit to Europe in the autumn of 1882, Henry Augustus Rowland, Professor of Physics at Johns Hopkins University, displayed diffraction gratings produced on a ruling engine he had designed and built, which were bigger and much higher quality than any previously made. Some were of a novel type, ruled on concave surfaces, which he used in a simple but equally novel spectroscope that he had devised, to reveal spectral lines in great detail, and by means of photography (...) to record spectral data much more rapidly than previously possible. Over about twenty years Rowland built three ruling engines, published photographic maps of the solar spectrum, compiled a catalogue of the wavelengths of lines in the solar spectrum correlated with laboratory-produced spectra of almost all the chemical elements, and produced and sold the diffraction gratings used by spectroscopists everywhere. For decades after his death Rowland’s ruling engines remained practically the only source of good-quality diffraction gratings. This paper describes and analyses this work of Rowland and of the other men, Theodore Schneider, John Brashear, and Lewis Jewell, who played major roles in it. (shrink)

The principle of relativity, that there is no preferred state of uniform motion, has recently come into conflict with certain cosmological observations. In an attempt to overcome this difficulty, an alternative formulation is explored in which this principle is replaced by the principle of universal time, while retaining the invariance of the speed of light. These two postulates lead to a well-defined world model in which one inertial frame has a preferred status. But the invariance properties of the laws of (...) physics are unaffected, and the model may be regarded as a modified form of special relativity which is in accordance with the new cosmological evidence. (shrink)

Feed-forward Pavlovian conditioning can serve as a proximate mechanism for the evolution of social behavior. Feed-forward can provide the impetus for animals to associate other individuals' presence, and cooperation with them, with the acquisition of resources, whether or not the animals are genetically related. Other social behaviors such as play and grooming may develop as conditioned stimuli in feed-forward social systems.

The objective of this work is to categorize the available fly ashes in different parts of the world into distinct groups based on its compositional attributes. Kohonen's self-organizing feature map and radial basis function networks are applied in a cascading fashion for the classification of fly ashes in terms of its chemical parameters. The basic procedure of the methodology consists of three stages: apply self-organizing neural net to ascertain possible number of groups, delineate them and identify the group sensitive attributes; (...) find mean values of sensitive attributes of the elicited groups and augment them as start-up prototypes in k-means algorithm and find the refined centroids of these groups; incorporate the centroids in a two layer radial basis function network and fine-tune the delineated groups and develop an indexing equation using the weights of the stabilized network. Further, to demonstrate the utility of this classification scheme, the so formed groups were correlated with their performance in High Volume Fly Ash Concrete System [HVFAC]. The categorization was found to be excellent and compares well with Canadian Standard Association's [CSA A 3000] classification scheme. (shrink)

The prelims comprise: Introduction The Mother of All Cells Embryonic Stem (ES) Cells Specialized Stem Cells Therapeutic Implications of Stem Cell Biology Cellular Philosophy and the Mind Problem The New Alchemists Stem Cell Biology: God in a Test Tube?

In “Two Concepts of Liberty” Berlin notes the protean nature of the word “freedom” and then systematically proceeds to narrow its range of meanings. In the process, Berlin eliminates much of what most people, in everyday communication, regard as freedom, believing that this is in the best interest of intellectual clarity. As he puts it: [N]othing is gained by a confusion of terms. To avoid glaring inequality or widespread misery I am ready to sacrifice some, or all, of my freedom: (...) I may do so willingly and freely: but it is freedom that I am giving up for the sake of justice or equality or the love of my fellow men. I should be guilt‐stricken, and rightly so, if I were not, in some circumstances, ready to make this sacrifice. But a sacrifice is not an increase in what is being sacrificed, namely freedom, however great the moral need or the compensation for it. Everything is what it is: liberty is liberty, not equality or fairness or justice or culture, or human happiness or a quiet conscience. (Emphasis added). Berlin's other, perhaps overarching, aim is to show how inattention to the specificity of the meanings of concepts might have potentially dangerous political repercussions. He implicitly argues that the intellectuals who promoted the idea of positive freedom as opposed to that of negative freedom contributed to the emergence of totalitarianism and fascism in Europe. (shrink)