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A nonverbal training module for a Teaching Laboratory was developed for and tested with secondary teacher-candidates enrolled in the University of Texas at Austin teacher education program. The unit, employing an awareness approach, was administered to 17 students in the experimental group immediately preceding the last of a series of required verbal teaching tasks. Curriculum materials were controlled for a cognitive gain measure. An objective observation system was developed for low-inference data. Test scores and nonverbal behaviors of experimental students were contrasted with those of another group of students (N=20). The training unit was effective in modifying four of 20 hypothesized changes in nonverbal behaviors. Further research concerning the most effective classroom nonverbal behaviors and the feasibility of teaching those behaviors appears warranted. (Author)

The teacher can use eye contact to communicate awareness to personalize attention, to individualize group instruction, to aid in classroom management, to provide individual motivation, and to prevent disciplinary problems. (AN)

It was proposed by Rushton in 1951, from theoretical considerations, that myelinated fibres less than 1 micron in diameter would conduct more slowly than unmyelinated fibres of the same size and that myelinated fibres below about 0.7 micron would not conduct at all. The experimental data on which he based his theory are all from the peripheral nervous system where small myelinated fibres are rare, and no experimental verification of Rushton's hypothesis has been attempted. In mammalian optic nerve, nearly all the fibres are myelinated; yet half have diameters below 1 micron, with many below 0.7 micron. The many studies of conduction velocities in the visual system enable a test of Rushton's hypothesis to be made. We have examined the correlations between conduction velocity and fibre diameter from a wide range of published studies of the mammalian visual system. The results of our analysis suggest that the small myelinated fibres of the optic nerve and optic tract conduct action potentials more rapidly than is predicted by Rushton's hypothesis, while the unmyelinated axons within the retina actually conduct more slowly than predicted. There is no reason to believe, in this case, that myelination of a small axon will reduce its conduction velocity.

The strategic use of information technology (I/T) is now and has been a fundamental issue for every business. In essence, I/T can alter the basic nature of an industry. The effective and efficient utilization of information technology requires the alignment of the I/T strategies with the business strategies, something that was not done successfully in the past with traditional approaches. New methods and approaches are now available. Thes trategic alignment framework applies the Strategic Alignment Model to reflect the view that business success depends on the linkage of business strategy, information technology strategy, organizational infrastructure and processes, and I/T infrastructure and processes. In this paper, we look at why it may not be sufficient to work on any one of these areas in isolation or to only harmonize business strategy and information technology. One reason is that, often, too much attention is placed on technology, rather than business, management, and organizational issues. The objective is to build an organizational structure and set of business processes that reflect the interdependence of enterprise strategy and information technology capabilities. The attention paid to the linkage of information technology to the enterprise can significantly affect the competitiveness and efficiency of the business. The essential issue is how information technology can enable the achievement of competitive and strategic advantage for the enterprise.

Several applications of Direct Chemical Oxidation (DCO) relevant to the demilitarization of munitions are reported and evaluated here. The role of low levels of transition metal catalysts on rate of oxidation of organics by peroxydisulfate was investigated, because such materials are normally present in demilitarization wastes and could conceivably alter the rate or effectiveness of DCO. It was found that the presence of transition metal ions of Fe, Co, Cu, and Mn had little or no accelerating effect. Silver alone substantially increased oxidation rate, except where segregated as AgCl by free chloride. The destruction of trace explosives on metal substrates (mild steel, copper and brass) was found to be effective in basic media, where the peroxydisulfate prevented corrosion of the base metal (anodic chemical passivation) without impeding oxidation of the organic explosive. A method of detection of completeness of reaction (based on mass- spectroscopic detection of the intermediate oxidation product, formaldehyde) was proposed. Rate data on the destruction of 2,4,6-trinitrotoluene by acidified ammonium peroxydisulfate is reported. Appended to the report is a comprehensive bibliography on DCO.

Medication classes historically used in the management of glaucoma include beta blockers, miotics, sympathomimetics and carbonic anhydrase inhibitors. Because topically applied medications are more site specific, they are preferred in the treatment of glaucoma. Compared with oral medications, topical agents are associated with a decreased incidence of systemic side effects. With topical administration, conjunctival and localized skin allergic reactions are relatively common, whereas severe reactions, including death, are rare. Recently introduced topical agents for glaucoma therapy include dorzolamide and brinzolamide, the first topical carbonic anhydrase inhibitors; brimonidine and apraclonidine, more ocular-specific alpha agonists; and latanoprost, a prostaglandin analog, which is a new class of glaucoma medication. Latanoprost has the unique side effect of increasing iris pigmentation. Like their predecessors, the newer agents lower intraocular pressure by a statistically significant degree. Preservation of visual field, the more substantial patient-oriented end point, continues to be studied.

Direct Chemical Oxidation (DCO) is a non-thermal, ambient pressure, aqueous-based technology for the oxidative destruction of the organic components of hazardous or mixed waste streams. The process has been developed for applications in waste treatment and chemical demilitarization and decontamination at LLNL since 1992, and is applicable to the destruction of virtually all solid or liquid organics, including: chlorosolvents, oils and greases, detergents, organic-contaminated soils or sludges, explosives, chemical and biological warfare agents, and PCB's. [1-15] The process normally operates at 80-100 C, a heating requirement which increases the difficulty of surface decontamination of large objects or, for example, treatment of a wide area contaminated soil site. The driver for DCO work in FY98 was thus to investigate the use of catalysts to demonstrate the effectiveness of the technology for organics destruction at temperatures closer to ambient. In addition, DCO is at a sufficiently mature stage of development that technology transfer to a commercial entity was a logical next step, and was thus included in FY98 tasks.

We have recorded the duration of lactational anovulation and amenorrhoea in a well-nourished group of Australian women who breastfed their babies throughout the study. The data enabled us to compare the theoretical cumulative probability of conception among breastfeeding women who had unprotected intercourse irrespective of their menstrual status with that of those who had unprotected intercourse only during lactational amenorrhoea. Breastfeeding alone is not an effective form of contraception, since all the women in our study resumed normal ovulation while still breastfeeding. However, among women who have unprotected intercourse only during lactational amenorrhoea but adopt other contraceptive measures when they resume menstruation, only 1.7% would have become pregnant during the first 6 months of amenorrhoea, only 7% after 12 months, and only 13% after 24 months. Thus for our women it would be possible to extend the Bellagio Consensus Conference guidelines which stated that lactational amenorrhoea can only be relied on as a contraceptive for the first 6 months post-partum in women who are fully or almost fully breastfeeding. The lactational amenorrhoea method can be relied on for excellent contraceptive protection in the first 6 months of breastfeeding, irrespective of when supplements are introduced into the baby's diet; for women who continue to breastfeed the method can also give good protection for up to 12 months post partum. Once menstruation has returned, other forms of contraception are essential to prevent pregnancy.The Bellagio Consensus Conference on breast feeding as a family planning method determined that a mother who is breast feeding and remains amenorrheic has a 98% rate of protection from pregnancy for 6 months postpartum. A prospective study of the duration of lactational anovulation and amenorrhea was conducted by recruiting 101 breast- feeding women before their infants were 6 weeks old. Salivary progesterone (2-4 times a week) and in a subgroup urinary estrogen and pregnanediol excretion rates 1 mg/24 hours indicated ovulation) were determined to check ovarian activity. The mean duration of amenorrhea was 9.5 months in 101 women, and anovulation lasted 10.6 months in 89 women. The mean age of infants was 5.3 months at the start of supplementary feeding. The probability of pregnancy was less than 3 months for 50% of nonlactating women, and 6 months for 85%. In contrast, the probability was 12 months postpartum for 50% of breast- feeding women. Thus, breast feeding was not a reliable form of contraception. Only 1.7% of breast-feeding women using contraception were likely to get pregnant by 6 months, 7% by 12 months, and 13% by the end of 2 years. The results were calculated from the incidence of potentially fertile ovulations prior to the 1st menses over 2-month (1- 12 months) or 3-month (13-24 months) intervals by proportional hazards modeling. In this sample of well-nourished women longer breast feeding could induce prolonged lactational amenorrhea with a major contraceptive effect for up to 12 months or more even after supplements were introduced. The lactational amenorrhea method is appropriate for women in traditional societies who tend to breast feed longer. It helps attain a 2-year birth interval, reduces the risk of maternal breast cancer, and the risk of gastrointestinal infections in infants.

We have studied a large group of Australian women breastfeeding for an extended period of time to determine the duration of lactational anovulation (n = 89) and amenorrhea (n = 101). Salivary progesterone assays were used to determine ovulation. These women had a mean of 322 days of anovulation and 289 days amenorrhea. Less than 20% had ovulated and less than 25% had menstruated by 6 months postpartum. The latest ovulation was at 750 days and the latest menstruation at 698 days. There was no significant correlation between any measure of maternal nutritional status and the duration of anovulation or amenorrhea. Neither the time of first supplement introduction to the baby nor the amount of supplement given was an accurate predictor of the return of ovulation or menstruation. However, our results clearly show that lactational amenorrhea can provide good protection against pregnancy in the 1st 6 months postpartum, even in well-nourished women who are giving their babies supplemental feeds.The authors studied a large group of Australian women who breastfed for a long period of time to determine the duration of lactational anovulation (n=89) and amenorrhea (n=101). Salivary progesterone assays were used to determine ovulation. These women has a mean of 322 days of anovulation and 289 of amenorrhea. Less than 20% had ovulated and 25% had menstruated by 6 months postpartum. The latest ovulation was at 750 days and the latest menstruation at 698 days. There was no significant correlation between any measure of maternal nutritional status and the duration of anovulation or amenorrhea. Neither the time of 1st supplement introduction to the baby nor the amount of supplement given was an accurate predictor of the return of ovulation or menstruation. However, these results show clearly that lactational amenorrhea can provide good protection against pregnancy in the 1st 6 months postpartum, even among well-nourished women who are providing their babies with supplement feeds.

Histochemical study of the distribution of cholinesterases in the cat medulla oblongata reveals that all neurones in the dorsal motor nucleus of the vagus (DMV) contain true cholinesterase (AChE) but, while most contain this enzyme alone, a small proportion of cells contain pseudocholinesterase (BuChE) as well. Cervical vagotomy affects the two types of cell to different degrees of severity. The BuChE-containing neurones lose their enzyme completely within 2-3 weeks and they atrophy and disappear as a result of the operation. On the other hand, the reaction is less severe and is reversible in those cells containing AChE only. Vagotomy also causes reduction of AChE and BuChE staining in the nearby area subpostrema; the depletion here is pronounced at 2-3 weeks and recovery occurs within the year. These findings suggest that some cells in the area subpostrema project peripherally via the vagus and that the area is part of the vagal nuclear complex. Moreover, capilllaries in the area contain AChE and BuChE in the endothelial lining and this is one of the few areas of the cat hindbrain to exhibit such vascular enzyme activity. The ependyma of the area postrema, which overlies the area subpostrema, is heavily stained for BuChE but this is unaffected by vagotomy.

A central archaeological and historical problem is that of population. It is reflected in the question often posed by the student or visitor of an ancient city: how big was X?; how many people lived here? The reply is unlikely to be more than an informed guess and, in most cases, a mere hazard, exposing a fundamental lacuna in historical knowledge. The problem of population size is not simply of casual interest; it affects almost every aspect of a balanced picture of life in ancient times.Explicit classical allusions to population figures survive in only a very few cases (Alexandria, for example, had more than 300,000 free inhabitants in the first century B.C., according to Diodorus). In their absence it is extremely difficult to assess the number of inhabitants of a city at a given time, a situation further complicated by the fact that in Roman times a city comprised not just a built-up area, perhaps defined by walls, but also a neighbouring territory which it owned. The inhabitants of the territorium were liable to be counted with the city dwellers, thus producing a definition of urban population which differs radically from our modern concept.Despite the inherent difficulties, demographic studies have periodically occupied the attention of a number of archaeologists and historians, and in recent years two major works have appeared. In The Economy of the Roman Empire Richard Duncan-Jones devotes an important chapter to the size of cities. After reviewing the various methods used to calculate the size of urban populations, he puts forward figures of his own, based principally on the interpretation of epigraphic evidence. As one of his examples has a specific Libyan connection, it is worth summarising here. The town concerned is Oea (modern Tripoli). Duncan-Jones applies an approach first outlined in 1886 by J. Beloch, in examining ancient records of large-scale gifts for public feasts or cash hand-outs (sportulae). These records provide important clues to the size of the urban population at the time of the benefaction. In the case of Oea, two pieces of evidence have been preserved. The first is given by Apuleius in the Apologia, a speech prepared for his defence (in a trial at Sabratha) against a charge of winning his Oean wife, Pudentilla, by magic.

Oestriol and progesterone concentrations were measured by specific radioimmunoassays in the saliva of six women on a daily basis during the last month of pregnancy, at frequent intervals during labour and daily during the puerperium. Salivary steroid concentrations are thought to reflect the circulating concentrations of the free hormone, and hence may be more biologically relevant than the total plasma concentration, or the urinary excretion of a metabolite. There was no sign of a fall in salivary oestriol or progesterone concentrations before the onset of labour. During the first and second stages, the concentrations fluctuated widely, perhaps due to alterations in uterine blood flow. After delivery of the placenta, hormone concentrations declined abruptly. Oestriol reached undetectable levels of J. Endocr. (1987) 115, 177–181

The distribution of acetylcholinesterase (AChE) has been examined histochemically in the lateral geniculate nucleus (LGN) of the cat and the monkey, and in the cat visual cortex. It was found that in the cat, AChE is most concentrated in laminae A and A1. Lamina C-proper possessed a weak band of AChE in its ventral part. Only restricted patches of activity were observed in the medial interlaminar nucleus. Laminae C1–3 and the central interlaminar nucleus possessed very little AChE. This pattern of enzyme distribution suggests that in the cat LGN, AChE activity coincides with the sites of neurophysiologically recorded X-cells, which are predominantly found in laminae A and A1 and are scarce in the C laminae and the medial interlaminar nucleus. The presence of AChE over neurones in layer VI of both areas 17 and 18 of the cerebral cortex in the cat suggests the corticothalamic pathway as one possible source of geniculate AChE activity. In the monkey LGN, AChE activity was observed in the parvocellular and magnocellular layers. The activity was greatest in the magnocellular layers, which are believed to contain neurons driven predominantly by retinal Y-cells. Thus, for this species the correlation between AChE activity and X-cells does not seem to hold.

A method based on the familiar coupling azo dye technique has been devised for the study of enzyme distribution in thick specimens. Its application to the study of esterase distribution in whole tadpoles of Xenopus laevis is described in detail. It can also be used to show the distribution of alkaline phosphatase, both in Xenopus tadpoles and in limbs dissected from chick embryos. It has proved useful in embryological studies both for teaching and for research.

Summary (1) The distributions of true cholinesterase (AChE) and pseudocholinesterase (ChE) in the spinal cord of the rat have been studied histochemically, by means of a thiocholine technique, at the light and electron microscope levels. (2) The somatic motoneurones in the ventral gray column contain high concentrations of AChE and are well demonstrated by the technique; the enzyme occupies the clefts of the rough endoplasmic reticulum and, in places, the nuclear envelope. The motoneurones are grouped into sub-columns which lie at the periphery of the ventral horn, the central portion of which is devoid of AChE-containing cells. Loss of enzyme following sciatic nerve section at mid-thigh level is restricted to the motoneurones in the retrodorsolateral sub-column in the last lumbar and first sacral segments. (3) The thoraco-lumbar part of the intermediolateral gray column contains AChE only, while the sacral part of the column contains both AChE and ChE. The enzyme content of the sacral intermediolateral column is unaffected by sciatic nerve section but is reduced following interruption of pelvic splanchnic nerves. (4) Apart from the neurones in the ventral and intermediolateral gray columns, cholinesterases are also found in certain other varieties of cells. AChE is present in neurones of the intermediomedial column and in cells lying in the lateral white funiculus adjacent to the substantia gelatinosa, while ChE is found in several small neurones scattered in the central portion of the ventral gray horn. These 3 varieties of cells are found throughout the length of the cord and they are all probably propriospinal as they are unaffected by peripheral nerve section.

A simultaneous coupling azo dye technique has been used to reveal the distribution of cholinesterase activity in the musculature of the developing tadpole of Xenopus laevis. The use of inhibitors and a less convenient but more specific histochernical technique confirmed that only true cholinesterase distribution was being demonstrated; and a study of silver-impregnated material proved that this azo dye technique provides a very convenient method of following the development of the patterns of myo-neural junctions in the striated muscles of this tadpole. A wide variety of patterns is seen in the various muscles: in the axial musculature the muscle-fibres become innervated at their ends from myocommatal plexuses and never acquire endings along their length; broad muscular sheets, as in the walls of the branchial and abdominal cavities, are also first innervated terminally from the septa but later acquire secondary innervation is along the lengths of the fibres. These different patterns of innervation are correlated with the functions of the various types of muscle. It is suggested that terminal innervation may be a special adaptation to permit rapid establishment of neurogenic activity, the pattern of endings of the more usual type forming when the need for precisely co-ordinated reflexogenic activity arises. In some muscles, the azo dye technique reveals a profuse multiple innervation of the fibres which are assumed to be of the so-called ‘slow type’ known to exist in some amphibian muscles.

1. Acetylcholinesterase in the hippocampal formation is located on the axonal membrane of cholinergic fibres of the alveus, in cholinergic neuropil, on the pre- and postsynaptic membranes at certain synapses, in the granular endoplasmic reticulum and the nuclear envelope of Golgi type II cells in the stratum oriens, and to a small extent in pyramidal cells. 2. The dense layers of acetylcholinesterase seen in certain layers of the hippocampal formation by light microscopy correspond to regions of dense cholinergic neuropil. 3. The terminals of cholinergic afferents in the hippocampal formation are predominantly axodendritic. 4. Axosomatic endings, though rare on pyramidal cells, are frequent on Golgi cells of the stratum oriens. 5. Light and dark cells can be distinguished in the granular layer of the dentate gyrus.

Small pieces of formalin-fixed tissue are infiltrated first with a 1% and then with a 2% solution of a low viscosity sodium alginate (a salt of a polymannuronic acid obtained from seaweed). This tissue is then transferred to a solution of a high molecular weight sodium alginate containing colloidally dispersed tricalcium phosphate. When a freshly prepared solution of gluconolactone is added, a calcium alginate gel is gradually formed—the lactone slowly hydrolyses to produce the free acid which liberates calcium ions from the colloidal phosphate. A block of gel containing the tissue is then cut out. If desired, it can be further hardened in a buffered calcium acetate solution and its cutting properties improved by soaking in 20% alcohol. At room temperature, enzymes such as the cholinesterases and phosphatases are not affected, but the procedure can be carried out at 0° C if desired. The gel does not crack and makes possible the cutting of coherent, serial frozen sections of many tissues. The alginate prep...

The reducing power of cells of Bact. lactis aerogenes has been measured by dye reduction tests with resting and with growing cultures in media containing as nitrogen sources ammonium salts or nitrate, and under aerobic and anaerobic conditions. Changes in growth rate have been correlated with changes in the reducing power accompanying transitions from one medium to the other or from anaerobic to aerobic conditions and vice versa. Two types of adjustment play a part in the observed phenomena: ( a ) rapid changes in concentrations of active intermediates, ( b ) slow adaptive modifications of enzyme systems in response to needs of the cell. The former are exemplified inter alia by the rapid fall in reducing power and growth rate when an anaerobic nitrate culture is aerated. The latter include the development of extra reducing power when the cell has to use nitrate as a source of nitrogen and of still more when the nitrate has to be reduced in presence of oxygen.