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The static force sensitivity of soleus tendon organ (Ib) afferents has been studied by noting their responses to graded force development produced by isometric contractions of either the whole muscle or single motor units. Data included responses of 23 Ib afferents to contraction of 8 whole muscles (8 experiments) and 16 Ib afferents to contraction of 30 motor units (5 experiments). Tendon organ responses of varying magnitude to contraction of the whole muscle or several of its individual motor units could be explained by differences in the number of muscle fibers that insert into each receptor's capsule and by differences in the contraction strength of these fibers. This finding suggests that soleus tendon organs have similar absolute sensitivities to static force development. An estimate was made of this absolute sensitivity and the value obtained (314 pps/g of force actually coupled to the receptor) is 2 orders of magnitude greater than those previously reported indices that simply relate Ib firing rate to force as measured at the tendon. The relationship between force exerted on a tendon organ's capsule and Ib firing rate is whown to be curvilinear and in keeping with a possible saturation effect that reduces the receptor's responsiveness to active contractions at relatively long muscle lengths.

Summary The interrelationships between axonal conduction velocity, tetanic tension, twitch contraction time and rate of force development during a tetanus have been studied in 126 motor units from 12 cat medial gastrocnemius muscles. While the range of axonal conduction velocities for slow- (contraction time > 45 msec) and fast-twitch units overlapped, the mean conduction velocity for the slow-twitch group was significantly lower. No difference could be found between the axonal conduction velocities of the fast non-fatiguing and fast fatiguing units. Within individual experiments, few significant correlations were found between conduction velocity and tetanic tension or contraction time for the fast- and slow-twitch units. Some correlations did appear when data from these populations were pooled, but such results are shown to be misleading. Some weak correlations were found between motor unit contraction strength and twitch contraction time. The rate of rise of isometric force development was found to be most strongly related to tetanic tension and only weakly related to contraction time. The ordering of motor units according to contraction strength reveals the association of motor unit mechanical properties to be ideally suited for the dual role of medial gastrocnemius as a postural and powerful phasic muscle.

The physiological properties of motor units in cat medial gastrocnemius have been studied with particular reference to fatigue. A broad range of fatigability was encountered, particularly within the fast twitch group. These findings were consistent with the vascular and histochemical profile of this muscle.

Spleens from developing rats of ages 16 days' gestation to 4 days after birth were prepared for electron microscopic study. At 16 days the spleen consists of a meshwork of intercommunicating spaces surrounded by mesenchymal or early reticular cells which show indications of collagen-forming activity. By 17 days these spaces are connected with the blood vessels and an open circulation is established. Some spaces are dilated and by 20 days begin to assume the characteristics of sinuses while the reticular cells are crowded together to form the sinus walls. Similar spaces, when collapsed against the contained cells, resemble the pulp cords. The endothelium of the blood vessels is differentiated by the 21st day and by 4 days after birth, basement membranes have appeared between cells lining adjacent sinuses. Erythropoiesis, established by 17 days, persists at least through the fourth postnatal day. White pulp formation is initiated on the second postnatal day.

SummaryGroups of young albino rats were treated either by repeated subcutaneous injections or by repeated forced feedings with dihydrotachysterol (Hytakerol) over periods ranging from 7 to 30 days, total dosage of the drug varying from .31 to 5.5 mg. The histological alterations in the long bones resulting from this treatment have been described. Significant changes were induced with relatively lower dosage when the drug was given by stomach tube but with either method were in direct proportion to the total dosage and duration of the experiment. The most striking changes consisted of the appearance of extensive channels, wide passageways and cystic cavities extending varying distances from the endosteal toward the periosteal surfaces of the cortex of the long bones. After prolonged oral administration most of the shaft was reduced to a trabecular meshwork. Some of these spaces were occupied by highly vascular hemopoietic tissue, with some infiltration of fibroblastic cellular tissue. Infrequently at the d...

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Electron microscopic studies reveal that the red pulp of the rabbit spleen is composed of reticular cells, reticulum and elements of the blood circulating through it. The three types of reticular cells described follow no definite pattern as to types of spaces they line and are not always adjacent to a basement membrane. Similar or dissimilar cells may line a basement membrane on the same or opposing sides. The entire red pulp area is intercommunicating through pores and junctions of the several spaces and in that area in which no basement membrane exists, the cytoplasmic projections of the reticular cells form a meshwork of spaces. Terminal arterioles are seen to end in collapsed type channels with a change from endothelium to Type I reticular cells. These rapidly join dilated areas. The reticular network of the spleen appears as four types: homogeneous, fibrillar, a combination of these, and reticular cells only. Isolated cilia are found in the reticular cell cytoplasm and are shown to be associated with a basal body and a centriole. The investigation supported the hypothesis that the red pulp of the spleen in the adult rabbit is a functionally dynamic area constantly changing its histological structure, both regarding cells and state of the vascular channels.

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When the Iranian cinema industry redeveloped after its destruction during the 1979 Islamic Revolution, children’s films became a means through which to question the impact of new social forms, especially in relation to children’s subjectivities. This questioning encouraged a dual visual perspective that swung between a point of view that observes the child character and a child’s point of view that is constituted diegetically as a cognitive stance from which the world is perceived. The technique is employed in the industry’s three main areas: films for young children, films about children, and young-adult films. Always subject to strict censorship, these films negotiate a narrow path between aesthetic pleasure and social critique. Initially, a cinema about boys, by the mid-1990s, films had begun admitting girls as major characters, and then, as funding for children’s films shrank, young-adult films with a focus on youth agency became a major form.

Two film retellings of fairy tales from the 1990s exemplify how familiar fairy tales can be reshaped to address major cultural preoccupations. On the one hand, the utopian narrative Ever After affirms neohumanistic values such as deep memory, knowable origins, and teleology in narrative and culture. In contrast, The Grimm Brothers' Snow White is postmodernist and dystopian, hybridizing apocalyptic and Gothic narrative structures and themes, and drawing on modern phenomena such as "the beauty myth," to present characters playing out an old story to an outcome which resists both teleology and closure.

This paper examines children’s literature as discourse and argues that attention to the textuality of children’s literature discloses a network of signifying strategies which serve to confine texts within a narrow band of socio-cultural values. The language of fiction written for children offers conventionalised discourses by means of which content is encoded. While there are many other books can be and are titled, these are culturally representative. They are symptomatic of the frames used in Australian children’s literature, and in effect disclose how that literature is complicit in the ideological construction of Australian childhood (or, in this case, adolescence). This is part of how children are socialized. Hence the mediators of children’s books focus attention on the ‘truth’-value of theme and content and perpetuate the illusion that discourse is merely transparent.

In recent decades, the debate about the role of the reader in the creation of "meaning" in a literary work, if viewed diachronically, has tended to shift from a position in which the "meaning" was seen as inhering in the work itself as object, with the reader as passive recipient, to one in which the reader's subjective response to the unfolding text is the action which is crucial. Hence variability of interpretation is inevitable, since no two readers bring the same range of cultural and experiential associations to the language of a text. While this last point is irrefutable, there has been a tendency lately to ignore the third person in the triad which makes up any reading of, say, a poem - the author. In the New Critical reaction against quasiautobiographical, pseudo-historical approaches to poetry, the text virtually came to obliterate the author and, more recently, the death of the author has been triumphantly proclaimed as the corollary of reader response criticism. Yet a significant contribution to the whole concept of the role of the reader can be made by studying a writer's successive drafts. Unless a poet, for example, can be questioned as to the purpose of his revisions, his reasons for altering the text remain a matter of speculation. On the basis of the alterations themselves, however, in both the specific change and its effect on the larger context - on the altered interactions of diction, syntax, imagery, rhyme and rhythm or shifts of focus in spatial and temporal dimensionssome of the ways the poet works to place constraints upon reader response can be brought out. For any change, no matter how trivial it seems, will influence, both qualitatively and cumulatively, the nuances of "meaning" expressed and affect the manner and extent to which the reader is persuaded to participate in the creation of meaning. Many illuminating examples are to be found in the revisions of Wilfred Owen's poetry and, while we would generally concur with

The kinetics and/or products of reaction, in nitric acid containing 0–5 mol dm–3 of dinitrogen pentaoxide, of phenyltrimethylammonium perchlorate, 1,2-dichloro-4-nitrobenzene, 2,4-dinitrotoluene, 1,4-dichloro-2-nitrobenzene, 1,2,4-trichloro-5-nitrobenzene, 1,2,4,5-tetrachlorobenzene, pentachlorobenzene, 1,2,3-trichlorobenzene, 1,3,5-trichloro-2-nitrobenzene, 1,2-dichloro-3-nitrobenzene, 1,2,3,4-tetrachlorobenzene, and 1,3-dichloro-2-nitrobenzene, have been studied. For each substrate investigated kinetically, rate coefficients for nitration in solutions containing more than ca. 2 mol dm–3 dinitrogen pentaoxide increase more quickly than the concentration of nitronium ion. In the cases of 1,2,4,5-tetrachlorobenzene, 1,4-dichloro-2-nitrobenzene, and 1,2,4-trichloro-5-nitrobenzene, but not with the other substrates, there was evidence for the formation of, in addition to expected aromatic nitroproducts, unstable cyclohexadiene products. Those from 1,2,4-trichloro-5-nitrobenzene were identified as a diastereoisomeric pair of 3,5,6-trichloro-2,4-dinitrocyclohexa-2,5-dienyl nitrates. A mechanism for the formation of these products is proposed.

A turbidity maximum is consistently observed in the upper reaches of the Tamar estuary at high water. Neap tide suspended particulate matter (SPM) concentrations are typically 20 ppm at high water; spring tide concentrations are typically an order of magnitude greater. The location of the turbidity maximum is usually associated with the freshwater-saltwater interface but occasionally occurs further up-estuary. At neap tides the maximum is less defined and can be masked by freshwater SPM concentrations. The spring tide maximum is generally small during winter periods, when it is located down-estuary, and reaches its largest concentrations during summer when it is close to the head. About 65% of the variance in the magnitude of the maximum at spring tides can be explained in terms of its distance from the head. The position of the maximum is determined mainly by freshwater runoff with a logarithmic regression explaining about 80% of the variance. Only 30–35% of the variance in the turbidity maximum magnitude and location at neap tides can be explained in terms of tidal range and runoff. A tidal resuspension model is considered which ignores density effects but which has a spatially independent, runoff dependent (but otherwise time independent) erodibility constant as a single “free” parameter. The model provides a reasonable description of the magnitude and location of the turbidity maximum in the Tamar, both at spring and neap tides, despite the fact that the maximum usually occurs near the freshwater-saltwater interface (which in itself would strongly suggest that gravitational circulation and intratidal stability effects have a strong influence on the location of the maximum). It is possible that all three mechanisms act together to produce a much narrower maximum than we have simulated, with resuspension being enhanced in the strongly mixed fresh water behind the interface, and tidal pumping and gravitational circulation accumulating sediment close to the interface.

Recently there has been brought to the attention of the writer a case, encountered by Dr. C. W. Pollard in his practice, which presented the interesting and rather unusual condition of almost total deficiency of the left side of the diaphragm. Associated with and doubtless as a result of this, there were found some other minor anomalies, the most evident of which was a misplacement of some of the abdominal viscera into the left pleural cavity. It was obvious that these misplaced viscera represent a spurious hernia, due to an arrest in development of the left side of the diaphragm, rather than a true hernia due to a lack of diaphragmatic muscular tonus or development, for these viscera were not enclosed in a hernial sac but lay free in the left pleural cavity. On reviewing the available literature concerning the subject of congenital diaphragmatic hernia it was found that the