Different Sequence Of Events Research Articles

"Describing What Never Happened": Jane Austen and the History of Missed Opportunities

"Describing What Never Happened":Jane Austen and the History of Missed Oportunities William Galperin I. Jane Austen's fictions are seemingly rife with missed opportunities. From her first published novel, Sense and Sensibility (1811), to her last completed novel, Persuasion (1817), the missed opportunity casts a shadow over Austen's world that her narratives never quite succeed in either dispelling or, even in Persuasion, fully redressing. Sense and Sensibility is forever haunted by the specter of John Willoughby, whose own reflections at the novel's close—in particular the "pang" he experiences at the thought of Marianne Dashwood's marriage to Colonel Brandon—are less a retributive instrument than a darkling echo of earlier prospects that the novel has concertedly nurtured.1 It is no accident surely that, in a typical gesture of damage control, the recent cinematic adaptation of Sense and Sensibility has no place for the most cinematic moment in the entire book: Willoughby's tenth-hour, and largely self-exculpatory, visit in the midst of Marianne's near-fatal illness. The movie, it is true, ends with a version of Willoughby in pang as he surveys Marianne's and Brandon's domestic tranquility from afar. But this grandiose and contrived image of him contravenes the novel's concluding observations (and directives), which are marked less by melodramatic longing than by a duller ache where the everyday is simply fraught and set against an horizon of plenitude from which life and its pleasures are a falling away: But that he was for ever inconsolable, that he fled from society, or contracted an habitual gloom of temper, or died of a broken heart, must not be depended on—for he did neither. He lived to exert, and frequently to enjoy himself. His wife was not always out of humour, nor his home always uncomfortable; and in his breed of horses and dogs, and in sporting of every kind, he found no inconsiderable degree of domestic felicity.2 [End Page 355] The countercurrent against which happiness must struggle for Willoughby, and the marital and gender division it projects, hardly requires unpacking. But what is less immediately clear is how the impedance to joy, both here and elsewhere in Austen, is as much a function of things as they are as an index of something missed or bypassed that does not belong entirely to the realm of fantasy. In addition to noting that Marianne remains Willoughby's "secret standard of perfection in woman," and a placeholder for the very plenitude that Willoughby had himself figured (and had figured as recently as his dramatic reentry to the narrative), the narrator projects a different sequence of events from those that have transpired. For "in the voluntary forgiveness" of his benefactor following his marriage to what the novel calls "a woman of character," Willoughby is given "reason for believing that had he behaved with honour towards Marianne, he might at once have been happy and rich." This is not of course how things have worked out, either for Willoughby or for Marianne, who is gloomily described as being "taken from" her family on the occasion of her marriage.3 Still, the force of any lesson derivable from these developments is mitigated not just by the imperatives of comedy, which see to it that Willoughby is left, more or less unpunished, in the company of his animals and diversions, but even more by what in the context of the novel is very nearly a historical imperative. In this respect, loss is not strictly speaking absence but a residue or trace of something sufficiently palpable in its lingering materiality that it literally blots both the comedic close and the sententia attached to it. Persuasion, by contrast, appears pitched in a different direction insofar as the interrupted union of Anne Elliot and Capt. Frederick Wentworth is identified at the novel's outset as the problem or missed opportunity that the narrative must somehow redress. But even as Persuasion is given over in nearly exclusive measure to restoring what was lost in the prehistory of the narrative, when Anne initially rejected Wentworth's proposal of marriage, it is far from clear that what Anne has missed, much less...

Comparison of matrix metalloproteinase expression during Wallerian degeneration in the central and peripheral nervous systems

The matrix metalloproteinases (MMPs) are a large family of zinc-dependent enzymes which are able to degrade the protein components of the extracellular matrix. They can be placed into subgroups based on structural similarities and substrate specificity. Aberrant expression of these destructive enzymes has been implicated in the pathogenesis of immune-mediated neuroinflammatory disorders. In this study we investigate the involvement of MMPs, from each subgroup, in Wallerian degeneration in both the central and peripheral nervous systems. Wallerian degeneration describes the process initiated by transection of a nerve fibre and entails the degradation and removal of the axon and myelin from the distal stump. A similar degenerative process occurs as the final shared pathway contributing to most common neuropathies. MMP expression and localisation in the peripheral nervous system are compared with events in the CNS during Wallerian degeneration. Within 3 days after axotomy in the peripheral nervous system, MMP-9, MMP-7 and MMP-12 are elevated. These MMPs are produced by Schwann cells, endothelial cells and macrophages. The temporospatial expression of activated MMP-9 correlates with breakdown of the blood-nerve barrier. In the CNS, 1 week after optic nerve crush, four MMPs are induced and primarily localised to astrocytes, not microglia or oligodendrocytes. In the degenerating optic nerve, examined at later time points (4, 8, 12 and 18 weeks), MMP expression was down-regulated. The absence of MMPs in oligodendrocytes and mononuclear phagocytes during Wallerian degeneration may contribute to the slower removal of myelin debris observed in the CNS. The low level of the inactive pro-form of MMP-9 in the degenerating optic nerve may explain why the blood-brain barrier remains intact, while the blood-nerve barrier is rapidly broken down. We conclude that the difference in the level of expression, activation state and cellular distribution of MMPs may contribute to the different sequence of events observed during Wallerian degeneration in the peripheral compared to the CNS.

Proton shuttle in green fluorescent protein studied by dynamic simulations.

As a direct simulation of a multistep proton transfer reaction involving protein residues, the proton relay shuttle between A and I forms of green fluorescent protein (GFP) is simulated in atomic detail by using a special molecular dynamics simulation technique. Electronic excitation of neutral chromophore in wild-type GFP is generally followed by excited-state proton transfer to a nearby glutamic acid residue via a water molecule and a serine residue. Here we show that the second and third transfer steps occur ultrafast on time scales of several tens of femtoseconds. Proton back-shuttle in the ground state is slower and occurs in a different sequence of events. The simulations provide atomic models of various intermediates and yield realistic rate constants for proton transfer events. In particular, we argue that the I form observed spectroscopically under equilibrium conditions may differ from the I form observed as a fast intermediate by an anti to syn rotation of the carboxyl proton of neutral Glu-222.

Sex Differences in Rats in the Development of and Recovery From Ethanol Dependence Assessed by Changes in Seizure Susceptibility

Previous investigations have found sex differences in rats in response to chronic ethanol exposure. The most dramatic differences were observed with anticonvulsant treatment during ethanol withdrawal, when seizure susceptibility is significantly increased. Sex differences in this response were found for both GABAergic and glutamatergic compounds. This study was aimed at exploring whether sex also influences the timing for the development of and recovery from ethanol dependence. Ethanol was administered in a liquid diet, with pair-fed animals receiving dextrose, substituted isocalorically for the ethanol. Ethanol dependence and withdrawal were assessed by measurement of seizure thresholds after abrupt removal of the ethanol diet. Seizure thresholds were determined by slow, tail vein infusion of the gamma-aminobutyric acidA-receptor antagonist bicuculline. Male and female rats displayed differences in timing for both onset and recovery from ethanol dependence, as determined by changes in ethanol withdrawal seizure susceptibility. Female rats were slower to develop dependence and quicker to recover compared with male rats. Furthermore, acute ethanol administration did not alter seizure susceptibility in pair-fed control animals, but it was anticonvulsant in ethanol-withdrawn rats. Ethanol-withdrawn female rats showed a greater response to acute ethanol administration than did male rats. This set of experiments uncovered additional sex differences in one measure of ethanol dependence and withdrawal. Proposed mechanisms for the development of ethanol dependence involve alterations in subunit assembly of gamma-aminobutyric acidA and NMDA receptors or various posttranslational modifications. In consideration of these findings, whatever mechanisms underlie the development of ethanol dependence, there is a different sequence of events in male compared with female rats. Studies are ongoing to determine associations between behavioral measures of ethanol dependence/withdrawal and selective neuronal adaptations.

Flower development in Pisum sativum: From the war of the whorls to the battle of the common primordia

The ontogeny of pea (Pisum sativum L.) flowers, as in many legume and nonlegume plant species, proceeds through a very different sequence of events from the same process in Antirrhinum majus and Arabidopsis thaliana. Using scanning electron microscopic analysis, we have characterized the early development of wild-type pea flowers and selected morphological characters or markers to break it down into different developmental stages. We used these markers as tools to characterize early alterations in flower development of several pea floral homeotic mutants. These mutants display phenotypes resembling those of: (1) floral meristem identity mutations, frondosus (brac); (2) class A mutations, calix carpellaris (cc); (3) class B mutations, stamina pistilloida (stp-1 and stp-2); and (4) class C mutations, petalosus (pe). According to the homeotic transformations observed in the pea floral mutants, it would appear feasible that the identity and developmental pattern of the four organ types in pea flowers are governed by at least the same three developmental functions, A, B, and C, proposed for the two model systems. However, our results suggest that, in pea, although these functions do have a similar role in the specification of organ identity shown by their counterparts in Arabidopsis or Antirrhinum, they may differ in the control of other processes, such as floral determinacy, organ number, or leaf development. The more remarkable features of pea flower ontogeny were the existence of four common primordia to petals and stamens, the early carpel primordium initiation, and the abaxial-adaxial unidirectional initiation of organ primordia within each different floral whorl, in contrast to the centripetal and sequential floral ontogeny in other plants. Organ differentiation within each of these common primordia appears to be a complex process that plays a central role in the ontogeny of pea flowers. Analysis of flower developmental pea homeotic mutants suggests that A, B, and C functions are necessary for the correct differentiation of organs from common primordia and that, in addition to its role in the specification of petals and stamens, B function, would be involved in conferring common primordia identity. Dev. Genet. 25:280–290, 1999. © 1999 Wiley-Liss, Inc.

Flower development in pisum sativum: from the war of the whorls to the battle of the common primordia

The ontogeny of pea (Pisum sativum L.) flowers, as in many legume and nonlegume plant species, proceeds through a very different sequence of events from the same process in Antirrhinum majus and Arabidopsis thaliana. Using scanning electron microscopic analysis, we have characterized the early development of wild-type pea flowers and selected morphological characters or markers to break it down into different developmental stages. We used these markers as tools to characterize early alterations in flower development of several pea floral homeotic mutants. These mutants display phenotypes resembling those of: (1) floral meristem identity mutations, frondosus (brac); (2) class A mutations, calix carpellaris (cc); (3) class B mutations, stamina pistilloida (stp-1 and stp-2); and (4) class C mutations, petalosus (pe). According to the homeotic transformations observed in the pea floral mutants, it would appear feasible that the identity and developmental pattern of the four organ types in pea flowers are governed by at least the same three developmental functions, A, B, and C, proposed for the two model systems. However, our results suggest that, in pea, although these functions do have a similar role in the specification of organ identity shown by their counterparts in Arabidopsis or Antirrhinum, they may differ in the control of other processes, such as floral determinacy, organ number, or leaf development. The more remarkable features of pea flower ontogeny were the existence of four common primordia to petals and stamens, the early carpel primordium initiation, and the abaxial-adaxial unidirectional initiation of organ primordia within each different floral whorl, in contrast to the centripetal and sequential floral ontogeny in other plants. Organ differentiation within each of these common primordia appears to be a complex process that plays a central role in the ontogeny of pea flowers. Analysis of flower developmental pea homeotic mutants suggests that A, B, and C functions are necessary for the correct differentiation of organs from common primordia and that, in addition to its role in the specification of petals and stamens, B function, would be involved in conferring common primordia identity. Copyright 1999 Wiley-Liss, Inc.

Adsorption and Decomposition of Dimethyl Methylphosphonate on Metal Oxides

The adsorption and decomposition of dimethyl methylphosphonate (DMMP) have been examined on four different metal oxide surfaces: aluminum oxide, magnesium oxide, lanthanum oxide, and iron oxide. Aluminum, magnesium, and lanthanum oxides are observed to behave in much the same way, with initial binding of the PO species to the surface at an acid site, followed by stepwise elimination of the methoxy groups, beginning at temperatures as low as 50 °C, which combine with surface hydrogens to yield methanol that evolves from the surface. The final product observed for these oxides is a surface-bound methylphosphonate, with the P−CH3 bond intact, which is resistant to further oxidation even in the presence of 70 Torr of oxygen at 300−400 °C. Adsorption on iron oxide yields a different sequence of events, with the initial adsorption occurring again with the PO moiety binding to an acid site, although there is some indication of the formation of a second type of surface complex. The primary interaction on iron ox...

Psychophysical precedents of migraine in relation to the time of onset of the headache: the migraine time line.

We conducted a prospective study of 19 female migraine patients who kept a diary four times per day at 8 AM, 1 PM, 6 PM, and 11 PM for 10 consecutive weeks. In the diary, the patients recorded the occurrence as well as the features and associated symptoms of their headaches. They also rated five mood states: alertness, tension, irritability, depression, and fatigue, as well as the quality of sleep and the incidence and stressfulness of daily hassles as measurements of stress. They quantified the variables through the use of 100-mm visual analog scales. In the diaries, we identified 68 migraine headaches of which 23 developed during the night, 19 during the morning, 16 during the afternoon, and 10 during the evening. The headaches which developed during the evening or night were preceded by an increased incidence of daily hassles during the afternoon. The headaches which developed during the morning or afternoon were preceded by increased tension the previous days. The day before the headaches which developed during the morning, the incidence of daily hassles was increased during the morning, afternoon, and evening. The increased tension at 1 PM was followed by increased fatigue at 6 PM, which was still present at 8 AM of the morning during which the headaches developed. The day before the headaches which developed during the afternoon, the increased tension at 6 PM was followed by increased alertness at 11 PM. The next morning, the stressfulness of daily hassles was increased at 8 AM, followed by increased tension and irritability at 1 PM. We conclude that there are three different sequences of events with regard to the psychophysical precedents of migraine, depending on the time of onset of the headache: the migraine time line.

The chemistry of decayed aspen wood and perspectives on its utilization

The objectives of this research were to investigate the proportion of decayed wood in mature aspen stems, its chemical composition and its potential utility as a fuel or as a substrate for conversion to fine chemicals as part of an integrated utilization scheme. Three sound and ten decayed aspen stems were sampled from a boreal forest site. Stem analysis indicate that on average, 20% of the merchantable stem volume was in advanced decay and that considerable sound wood recovery was possible. Wood specific gravity and chemical composition were determined. The holocellulose content (volumetric basis) in advanced decayed wood was reduced by 67%. Thermal analysis of the wood using a differential scanning calorimeter provided graphical evidence of a different sequence of events occurring during the combustion of decayed wood and a resulting heat content per unit weight that was 40% higher than that of sound aspen wood. A higher degree of enzymatic hydrolysis was attainable with white-rotted aspen wood. Approximately 62% of the theoretical glucose yield was obtained from decayed aspen wood after alkali-peroxide pretreatment followed by a 12 hour hydrolysis using technical grade enzymes. The above information is used to elucidate future opportunities for wood recovery and energy production from decayed wood resources.

Constructing Schemata While Reading Simple Stories

Abstract Twenty-five undergraduates were timed while they read simple stories about ordered events and while they responded to true-false test questions about the order of the events in the stories. Three different sequences of events were used in the stories—a chronological sequence (1-2-3), and two different flashback sequences (1-3-2 and 2-1-3). The sequence of events in the stories affected the amount of time the subjects took to read the stories, but not the amount of time the subjects took to respond to the test questions, supporting the hypothesis that the subjects constructed an ordered schema while they read the story, rather than while they took the test.

The adsorption and reactions of NO 2 on the Ag(111) surface II. Adsorption at 25 K and annealing to 300 K

XPS has been used to follow the adsorption of NO 2 on Ag(111) at 25 K followed by annealing to 300 K. For initial conditions of thick multilayers at 25 K reactions with the substrate are identical to those at 90 K; initial adsorption is dissociative to NO(ads) + O(ads) and the final state on warming from 25 to 300 K. is NO 3(ads). At intermediate annealing temperatures, however, reactions are observed within the bulk N 2O 4 condensed phase which were not observed for the studies at 90 K where these initial thicknesses of condensate were not achieved. Between 112 and 145 K the equilibrium between N 2O 4 and NO 2 changes drastically, producing a pure NO 2 monomer condensed phase. No XPS spectrum of NO 2 monomer, gaseous or condensed, seems to have been reported before. Desorption occurs rapidly at temperatures at and above this conversion. Starting with a low coverage of N 2O 4 at 25 K produces a different sequence of events on annealing to 300 K. Only traces of NO 2 monomer are observed and only a small amount, if any, of NO 3(ads) is produced. By 300 K these species and most of the initially dissociated product, NO(ads), have all desorbed leaving dominant a oxygen species which we believe must be OH(ads) on the surface, based on its O(1s) BE.

Widows and divorcees: The same or different?

Abstract On the surface, widows and divorcees appear to be confronted with a number of similar problems. Their reactions to being single again, sometimes quite suddenly, are frequently based, however, on a different sequence of events. The similarities and differences of the two statuses are discussed as they are affected by legal issues and in terms of the implications in therapy.

Androgen cytosol binding during compensatory overload-induced skeletal muscle hypertrophy.

This study was undertaken to evaluate whether the increased androgen cytosol binding is an early or later event in the sequence of skeletal muscle hypertrophy induced by surgical overload. Following removal of the synergistic gastrocnemius and soleus muscles, plantaris muscle weights of overloaded hypophysectomized made rats were heavier than those in the control by 29% at 2 days, 41% at 7 days, 38% at 14 days, and 47% at 35 days. Androgen cytosol receptor binding capacities (femtomoles per milligram protein), determined using a synthetic androgen, [3H]methyltrienolone (R1881), were higher than observed in muscles of controls at all points of muscle enlargement. At high concentrations of labeled ligand, Scatchard analyses became nonlinear and were resolved using a two-component binding model. Receptor capacity of the higher affinity "androgenic component" for methyltrienolone binding in plantaris muscles was lower at 2 days but 60-80% higher at 7, 14, and 35 days in the hypertrophied group than in the control group. The lower affinity "glucocorticoid component" was higher in the overloaded group at all points following surgery. Several glucocorticoids and estradiol-17 beta competed equally with androgens for methyltrienolone binding. However, when cytosols were incubated with triamcinolone acetonide to block methyltrienolone binding to glucocorticoid receptors, the androgenic component was highly specific for androgens. These results show that total [3H]methyltrienolone cytosol concentrations increased in parallel with the muscle hypertrophy, yet the individual components of methyltrienolone binding attained greater concentrations in overloaded muscles by an apparently different sequence of events.

Insulin stimulation of hepatic malic enzyme activity in normal and diabetic rats controlled by different regulatory processes.

A comparison of the processes controlling the increase in hepatic malic enzyme activity in insulin-treated normal and diabetic rats indicated the existence of two distinct regulatory mechanisms. Livers were removed at 12, 36, and 60 h after insulin treatment of normal and alloxan-diabetic rats, and the activity, quantity, and specific activity (units/nmol), of malic enzyme was determined. In normal rats, a significant increase in activity occurred 12 h after insulin, whereas 36 h of insulin treatment was required for diabetic rats to show an increase in enzyme activity. This suggested that the return of malic enzyme activity from the depleted levels measured in diabetic rats probably involved a different sequence of events. A malic enzyme specific radioimmunoassay confirmed this. The increase in activity in insulin-treated normal rats was due to an increase in the quantity of malic enzyme. In insulin-treated diabetic rats, the increase in activity resulted from increases in both enzyme quantity and the specific activity of the enzyme, which returned to levels observed in normal rats.

The Cretaceous-Tertiary Boundary: Chronostratigraphic Position and Sequence of Events

The Cretaceous-Tertiary boundary has always been considered to be exceptional and linked to special events and mechanisms where catastrophes have often been advocated. The boundary stratotype, Stevns Klint in Denmark, has been paleomagnetically analysed. The C/T boundary is now given an absolute age of 66.7 m.y. The boundary is shown to have occurred under stable geomagnetic conditions, about 165,000 years before the polarity reversal of the base of Anomaly 29, and about 0.7-1.0 m.y. before the extinction of dinosaurs in New Mexico. Significant disturbances in the Earth's rate of rotation and direction of spin axis at the passing from the Cretaceous into the Tertiary are strongly contradicted. The CAT boundary events cannot be explained by a single large catastrophe. A sequence of different events and some gradualism need also to be included in present and future scenarios of the boundary events.

True Divergent Differentiation in a Cellular Slime Mold, Polysphondylium pallidum

Three abstract models of divergent cell differentiation to multiple cell types are presented. These differ primarily in the proportion of developmental events common to the pathways leading to each cell type. Two experimental approaches are outlined to determine which type best describes divergent differentiation occurring in a particular organism. The first technique is to describe and compare changes in labeling of specific polypeptides which characterize development to the several cell types. The second is to observe the ability of mutants which are blocked in one pathway to develop along alternate pathways. These approaches are applied to the case of Polysphondylium pallidum, where amebae develop into stalk cells, spores, or microcysts. It is concluded that cell differentiation in P. pallidum is of the truly divergent type in which developing cells show identical sequences of events until a branch point, and thereafter very different sequences of events.

Metastatic patterns of cancers of the lymphopoietic system in man.

Autopsy records are analyzed for 358 patients with reticulum cell sarcoma, lymphocytic lymphosarcoma, or Hodgkin's disease. These records belong to a series of 4,728 autopsy records collected by the Department of Pathology at Roswell Park Memorial Institute from 1957 through 1965. This paper analyzes the distribution of metastases at specific sites in 3 malignant lymphomas. The concept of soil specificity is discussed in connection with the excess of metastases at specific sites. Soil specificity is defined as a higher than expected occurrence of metastases due to a cancer in an organ when compared to other similar primary cancers. In some instances, however, the excess of metastases in a specific site was sometimes also related to the site of origin of a malignant lymphoma. Entire series of organs located either in the abdomen or pelvis showed metastatic patterns which were very likely related to the primary sites of origin. The metastatic patterns of lymphocytic lymphosarcoma and reticulum cell sarcoma appeared to be markedly different from those of Hodgkin's disease. Reticulum cell and lymphocytic lymphosarcomas were not only more widespread than Hodgkin's disease, but the patterns of abdominal and pelvic metastases strongly suggested either their multifocal origin or a different sequence of events in the seeding of lymph node areas, as compared to those of Hodgkin's disease. The relationship between the degree of anaplasia of certain lymphomas and blood-borne metastases is discussed.

Pathogenesis of Nutritional Cirrhosis

There are at present a number of concepts of the pathogenesis of cirrhosis, the most widely held of which is that cirrhosis develops as degeneration, nodular regeneration, and fibrosis occur in sequence. 1-4 According to this view, a variety of etiologic factors damage liver cells, many of which die while others regenerate. Foci of nodular regeneration are thought to occur in this way, compressing the stroma that formerly surrounded necrotic cells, giving rise to fibrous bands. In studies of rat and human liver in various stages of cirrhosis I have found a different sequence of events in the development of the cirrhotic process. Using tritiated thymidine (H 3 -thymidine) and autoradiography to detect proliferating cells, the earliest change giving rise to fibrosis was proliferation of cells of blood vessels and lymphatics. From these studies, the pathogenesis of nutritional cirrhosis is suggested to be as follows. Swelling of liver and Kupffer

Studies of Rickettsial Toxins

Studies of Rickettsial Toxins

CHANGES IN HUMORAL IMMUNITY OCCURRING DURING THE EARLY STAGES OF EXPERIMENTAL PNEUMOCOCCUS INFECTION

A study was made of the changes in humoral immunity occurring during the early phases of experimental pneumococcus infection in the dog and cat. The methods devised by Robertson and Sia were employed to demonstrate the presence of anti-pneumococcus properties in the serum of animals naturally resistant to this micro-organism. It was found that with a generalized and overwhelming infection accompanied by early blood invasion, there was a prompt and rapid decrease in the concentration of natural humoral immune bodies which frequently disappeared entirely by the time of death. This same early diminution of humoral immune substances, opsonins, agglutinins, and pneumococcidal-promoting bodies was observed in animals that survived a moderately severe generalized infection but the concentration of immune bodies rose again with the onset of recovery. The decrease in concentration of humoral immune substances during a severe generalized infection appeared to be due to the combination of "S" substance with the normal immune bodies. When the pneumococcus infection was more localized as in the case of true lobar pneumonia a quite different sequence of events was observed to occur. Several animals, in which extensive lobar pneumonia was produced, showed the presence in quantity of humoral immune bodies in the blood throughout the course of an infection terminating fatally. These findings suggest that after the inception of pneumococcus infection in the dog and cat the chief function of natural anti-pneurnococcus substances in the blood is to limit or prevent blood invasion. When pneumococcic infection is localized these circulating antibodies appear to have little effect either in preventing the spread of the process or determining the outcome of the disease.