Optimization of trial wave functions for use in quantum Monte Carlo with application to LiH

Methods for both partial and full optimization of wavefunction parameters are explored, and these are applied to the LiH molecule. A partial optimization can be easily performed with little difficulty. But to perform a full optimization we must avoid a wrong minimum, and deal with linear-dependency, time step-dependency and ensemble-dependency problems. Five basis sets are examined. The optimized wavefunction with a 3-function set gives a variational energy of -7.998 + 0.005 a.u., which is comparable to that (-7.990 + 0.003) 1 of Reynold's unoptimized \fin ( a double-~ set of eight functions). The optimized wavefunction with a double~ plus 3dz2 set gives ari energy of -8.052 + 0.003 a.u., which is comparable with the fixed-node energy (-8.059 + 0.004)1 of the \fin. The optimized double-~ function itself gives an energy of -8.049 + 0.002 a.u. Each number above was obtained on a Bourrghs 7900 mainframe computer with 14 -15 hrs CPU time.

Organizational change: implications of culture and leadership in the transformation to a total quality management paradigm

The study was undertaken to investigate organizational readiness for change to a total quality management (TQM) paradigm as the corporate-wide strategy within a long-term care facility. The focus of the study was on leadership values and organizational cultural characteristics that could either accelerate or impede the change process at The Public Hospital. structurally, the ~tudy included 'three distinct components. The first component examined the management philosophy outlined by Deming (1986) and his contemporary Juran (1989) in order to determine what leadership values best support the new Total Quality Management paradigm. Secondly, this information was compared to present leadership values at The Public Hospital with the purpose of identifying opportunities for improvement within the organization's current culture as the hospital moves toward the desired TQM culture. The final component, a roadmap, was developed to reflect the most appropriate direction for organizational change at The Public Hospital.

Out of the darkness and into the light : a study of inauthentic and authentic speech

Introduction Man can be described as the being who shows himself in speech, and from birth to death is continually speaking. Communication is so close to us, so woven into our very being, that we have little understanding of the way it is constituted; for it is as hard to obtain distance from communication as it is to obtain distance from ourselves. All communication is not alike. There are two basic modesl of communication, the inauthentic and the authentic, between which there occurs a constant tension. It is in the inauthentic mode, points out Heidegger, that we find ourselves "proximately and for the most part"; 1. Being and Time, pg. 68 Dasein decides as to the way it will comport itself in taking up its task of having being as an issue for it. " •.• it~, in its very being 'choose' itself and win itself; it can also lose itself and never win itself or only "seem" to do so. But only in so far as it is essentially something which can be authentic--that is, something of its own--can it have lost itself and not yet won itself." 2. therefore Heidegger also terms it "everydayness".2 Caught up in the world of everydayness, our speaking covers over and conceals3 our rootedness in being, leaving us in the darkness of untruth. The image of darkness may be inferred from Heidegger's use of the image of "clearing,,4 to depict being as 2. ibid. pg. 69 "Dasein's average everydayness, however, is not to be taken as a mere 'aspect'. Here too, and even in the mode of inauthenticity, the structure of existentiality lies ~ priori and here too Dasein's being is an issue for it in a definite way; and Dasein comports itself towards it the mode of average everydayness, even if this is only the mode of fleeing in the face of it and forgetfulness thereof." 3. ibid. pg. 59 "covering over" and "concealing" are 1;yays Dasein tries to flee its task of having being as an issue for itself. " ••• This being can be covered up so extensively that it becomes forgotten and no question arises about it or its meaning ••• n How everyday speaking accomplishes this will be taken up in detail in the second chapter which explores Dasein's everyday speech. 4. ibid, pg. 171 lI ••• we have in mind nothing other than the Existential - ontological structure of this entity (Dasein), that it is in such a way as to be its 'there'. To say that it is -' illuminated' [tlerleuchtet"] means that as Being-in-theworld it is cleared [gelichtetJ in itself7 not through any other entity, but in such a way that it is itself the clearing. Only for an entity which is eXistentially cleared in this way does what is present-at-hand become accessible in the light or hidden in the dark •••• " 3 dis-coveredness and truth. Our first task will be to explore the nature of communication in general and then to explore each of the modes manifested in turn. The structure of the inauthentic mode of communication can be explored by asking the following questions: What is this speaking about? Who is it that is speaking and who is spoken to? Does this speaking show man in his speech? The authentic mode is distinguished by the rarity with which we encounter it; as the inauthentic conceals, so the authentic reveals our rootedness in being. Yet this rarity makes it difficult to delineate its elusive structure clearly. Its constituent elements can be brought into focus by asking the same questions of this mode that we previously asked of the inauthentic mode. Our initial response to the disclosure of the authentic mode is to attempt to abandon the inauthentic mode and leave the darkness behind dwelling only in the "lighted place". All through the ages, some men pushing this to extreme, have, upon uncovering their relatedness to being, experienced a deep longing to dwell in such a "place" of pure truth and oft times denigrated or attempted to exclude the everyday world. Such 4. flight is twice mistaken: first it atbempts to fix truth as unchanging and static and secondly, it opposes this to untruth which it seeks to abolish. This is both the wrong view of truth and the wrong view of untruth as Heidegger points out in The Origin of The-Work of Art: The Way-to-be of truth, i.e., of discoveredness, is under the sway of refusal. But this refusal is no lack or privation, as if truth could be simply discoveredness rid of all covers. If it could be that, it would no longer be itself . ••• Truth in its way-to-be is untruth.5 Pure light is not the nature of Being nor is pure unconcealedness possible for man. Failure to remember this is the failure to realize that communication destroys itself in such flight because it no longer maintains the contingency of its task, i.e., the dis-closedness of being. We are reminded of the strong attraction this flight from darkness held for Plato. Light, truth and Being are all beyond the darkness and have nothing to do with it. In Book VII of the R~public, Socrates' explanation of the Allegory of the Cave to Glaucon points to a decided preference men have for the "lighted place". 5. The Origin Of The Work Of Art, pg. 42 5. Come then, I said, and join me in this further thought, and do not be surprised that those who attained to this height are not willing to occupy themselves with the affairs of men, but their souls ever feel the upward urge and yearning for that sojourn above. For this, I take it, is likely if in this point too the likeliness of our image holds. 6 Despite the attraction to pure truth, human communication is more complex than putting down one mode of communication and picking up another. Due to the fact that we are always on the way, the title of my thesis will have to be amended: OUT OF THE DARKNESS AND INTO THE LIGHT--AGAIN AND AGAIN. It must be this way because this is what it means to be human. This is the point made by Mephisto to Faust in pointing out that man, standing between God and the devil, needs both darkness and light: Er findet sich in einem ewigen Gl~t Uns hat er in die Finsternis gebracht, Und euch taugt einzig Tag und Nacht. 7 6. Republic z (517 c & d) It should be noted however, that while the philosopherking must be compelled to return to the cave for purely political reasons, once he has taken adequate view of the "brightest region of being" he has the full truth and his return to darkness adds nothing to the truth. 7. Faust, pg. 188 6. This thesis proposes to examine the grounds that give rise to communication, uncovering the structure of its inauthentic and authentic modes and paying close attention to tpeir interrelationship and to their relationship to language as "the house of Being": language that both covers and opens up man's rootedness in Being, transforming him as he moves along his way, taking up his "ownmost task" of becoming who he is. roots. He is the being who shows himself inn that reflects his forgetfulness or remembrance of his rootedness in being. Man comes into an already existent world and is addressedl through things in the world which are c

Palaeopigment accumulation and implcations for paleolimnology over the lost century for two Ontario lakes

Crawford Lake is a meromictic lake, which is 24 m deep and has an area of 2.5 ha, and has never been reported to have mixed below 16 m. Lady Evelyn Lake, which became a reservoir when a dam was built in 1916, is dimictic with a maximum depth of about 35 m. 1 My research proved that both native chlorophylls and the ratio of chlorophyll derivatives to total carotenoids were better preserved in the shallower lake (Crawford Lake) because it was meromictic. Thus the anaerobic conditions in Crawford Lake below 16 m (monimolimnion) provide excellent conditions for pigment preservation. Under such conditions, the preservation of both chlorophylls and carotenoids, including oscillaxanthin and myxoxanthophyll, are extremely good compared with those of Lady Evelyn Reservoir, in which anaerobic conditions are rarely encountered at the mud-water interface. During the period from 1500 to 1900 A. D. in Crawford Lake, the accumulation rates of oscillaxanthin and myxoxanthophyll were extremely high, but those of chlorophyll derivatives and total carotenoids were relatively low. This was correlated with the presence of a dense benthic mat of cyanobacteria near the lake's chemocline. Competition for light between the deep dwelling cyanobacteria and overlying phytoplankton in this meromictic lake would have been intensified as the lake became more and more eutrophic (1955-1991 A. D.). During the period from 1955 to 1991 A. D., the accumulation rates of chlorophyll derivatives and total carotenoids in the sediment core from Crawford Lake (0-7.5 cm, 1955-present) increased. During this same period, the accumulation rates of cyanobacterial pigments (Le. oscillaxanthin and myxoxanthophyll) declined as the lake became more eutrophic. Because the major cyanobacteria in Crawford Lake are benthic mat forming Lyngbya and Oscillatoria and not phytoplankton, eutrophication resulted in a decline of the mat forming algal pigments. This is important because in previous palaeolimnological studies the concentrations of oscillaxanthin and myxoxanthophyll have been used as correlates with lake trophic levels. The results of organic carbon a13c analysis on the Crawford Lake sediment core supported the conclusions from the pigment study as noted above. High values of a13c at the depth of 34-48 cm (1500-1760 A. D.) were related to a dense population of benthic Oscillatoria and Lyngbya living on the bottom of the lake during that period. The Oscillatoria and Lyngbya utilized the bicarbonate, which had a high a 13C value. Very low values were found at 0-7 cm in the Crawford sediment core. At this time phytoplankton was the main primary producer, which enriched 12C by photosynthetic assimilation.

Paleoindicators of meromixis

This study was undertaken to ascertain whether meromictic lakes could be differentiated from holomictic lakes on the basis of their surficial profundal sediments. Surface sediment cores (15 cm long) were collected from both the littoral and profundal zones of four meromictic and six holomictic lakes and analyzed for total number of fossil chironomid headcapsu~es, chlorophyll and carotenoid degradation products as well as \ iron and manganese concentrations. Littoral and profundal comparisons of the surface sediments were made between the two lake types using the Mann-Whitney U test. Iron, manganese and the iron to manganese ratio in the littoral sediments of meromictic lakes were significantly lower than those found in the littoral sediments of holomictic lakes. The observed differences are believed to represent an artifact of the significantly higher carbonate concentrations found in three of the four meromictic lakes studied. Profundal and littoral to profundal ratio comparison between holomictic and meromictic lakes suggest that the significantly lower iron and higher carotenoid concentrations in meromictic profundal sediments were a con~equence of meromixis. However, the overlap in distribution exhibited by both iron and carotenoid degradation products between the two lake types was sufficiently large in this study to nullify their use as a means of differentiating meromictic from holomictic lakes. A long core (4.25 m) was removed from the deepest part of the meromictic Crawford Lake (Ontario), sectioned at 5 cm intervals, and analyzed to assess when meromixis occurred, based on its fossil record. Temporal changes in the total number of chironomid headcapsules, and chlorophyll and carotenoid sediment degradation products were closely correlated with organic matter, indicating in my opinion that extensive redeposition of littoral chironomid headcapsules in the profundal zone has occurred. Temporal variations in carotenoid degradation products, in response to changes in organic matter, obscured increased preservation that may have occurred as a consequence of meromixis. Temporal variations in iron and manganese suggest that relatively stable redox conditions have existed throughout most of the lake's history. Therefore it would appear that Crawford Lake has been meromictic since its inception.

Palladium and platinum complexes of vitamin Bâ

Palladium and platinum complexes of pyridoxamine, pyridoxine and pyridoxal have been prepared. The structures of the complexes PtCI2PM.H20, trans-PdC12 (PN)2 and [PLH+ ]2[PtC16] 2- ,H20 have been determined by use of single crystal x-ray studies. The compounds PdC12PH, trans-PdC12 (PN) 2 , cis-PdCI2 (PN)2 and cis PdC12 (PL)2 were also studied by use of carbon-13 nmr spectroscopy. All the complexes have also been characterised by use of infrared spectral studies. In the complexes, PtCI2PM.H20 and PdC12PM, the ligand pyridoxamine is chela ted to the metal through the aminomethyl nitrogen and the phenolate oxygen atoms whereas in the complexes, trans-PdCI2 (PN)2' cis-PdCI2 (PN)2 and cis-PdC12 (PL)2 the vitamin B6 ligands are coordinated to the metal through the pyridine ring nitrogen. The compounds [PLH+ ]2[PtCI6] 2- .H20 and [PMH2] 2+ [PdCI4] 2- .H20have no direct metal-ligand bonding, In all the complexes, the metal maintains a square planar coordination except in [PLH +] 2[PtCI6] 2- ,H20 where the metal is octahedrally coordinated. PH pyridoxamine [PMH ] 2+ = diprotonated pyridoxamine 2 PN = pyridoxine PL pyridoxal PLH+ protonated pyridoxal

Paragenetic history of the Ordovician Trenton Group carbonates, Southwestern Ontario

Geochemical examination of the rock matrix and cements from core material extracted from four oil wells within southwestern Ontario suggest various stages of diagenetic alteration and preservation of the Trenton Group carbonates. The geochemical compositions of Middle Ordovician (LMC) brachiopods reflect the physicochemical water conditions of the ambient depositional environment. The sediments appear to have been altered in the presence of mixed waters during burial in a relatively open diagenetic microenvironment. Conodont CAl determination suggests that the maturation levels of the Trenton Group carbonates are low and proceeded at temperatures of about 30 - 50°C within the shallow burial environment. The Trenton Group carbonates are characterized by two distinct stages of dolomitization which proceeded at elevated temperatures. Preexisting fracture patterns, and block faulting controlled the initial dolomitization of the precursor carbonate matrix. Dolomitization progressed In the presence of warm fluids (60 75°C) with physicochemical conditions characteristic of a progressively depleted basinal water. The matrix is mostly Idiotopic-S and Idiotopic-E dolomite, with Xenotopic-A dolomite dominating the matrix where fractures occur. The second stage of dolomitization involved hydrothermal basinal fluid(s) with temperatures of about 60 - 70°C. These are the postulated source for the saddle dolomite and blocky calcite cements occurring in pore space and fractures. Rock porosity was partly occluded by Idiotopic-E type dolomite. Late stage saddle dolomite, calcite, anhydrite, pyrite, marcasite and minor sphalerite and celestite cements effectively fill any remaining porosity within specific horizons. Based on cathode luminescence, precipitation of the different diagenetic phases probably proceeded in open diagenetic systems from chemically homogeneous fluids. Ultraviolet fluorescence of 11 the matrix and cements demonstrated that hydrocarbons were present during the earliest formation of saddle dolomite. Oxygen isotope values of -7.6 to -8.5 %0 (PDB), and carbon isotope values of - 0.5 and -3.0 %0 (PDB) from the latest stage dog-tooth calcite cement suggest that meteoric water was introduced into the system during their formation. This is estimated to have occurred at temperatures of about 25 - 40°C. Specific facies associations within the Trenton Group carbonates exhibit good hydrocarbon generating potential based on organic carbon preservation (1-3.5%). Thermal maturation and Lopatin burial-history evaluations suggest that hydrocarbons were generated within the Trenton Group carbonates some time after 300 Ma . Progressively depleted vanadium trends measured from hydrocarbon samples within southwestern Ontario suggests its potential use as a hydrocarbon migration indicator on local (within an oilfield) and on regional scales.

Parental beliefs as predictors of children's externalizing behaviors

The relationship between maternal beliefs about children's externalizing behaviors (EB) and the frequency of their children's EB was investigated. The sample of 71 consisted of two groups of mothers of children between 8-12 years of age. The Clinic group consisted of 35 mothers of children referred to a Children's Clinic due to externalizing behavior problems. The School group consisted of 36 mothers of children attending elementary school. Mothers completed questionnaires measuring parental beliefs and the frequency of their children's EB. Results showed that mothers' endorsement of authoritarian parenting was positively related to children's EB scores. A U-shaped relationship was found between mothers' relationship-centered goals and children's EB scores. Parent-centered goals and children's EB scores were positively correlated only in the clinic group. Mothers'-hostile attribution scores were positively related to their children's EB scores in both groups. Mothers with low perceived parenting scores were associated with higher children's EB scores in both groups. Overall, results revealed potential clinical implications. Parenting programs that change parenting goals, attributions, and ii Parental Beliefs sense of parenting control, which in turn influences parenting behavior, may influence the frequency of their children's externalizing behaviors.

Parental care in the common tern (Sterna Nirundo): sexual roles in a monogamous seabird

The parental behaviour of male and female Common Terns (Sterna hirundo) was documented throughout two breeding seasons at a colony near Port Colborne , Ontario. Thirteen and fourteen pairs of terns were chosen for intensive study in 1982 and 1983, respectively. The delivery of fish by males to their mates ("courtship feeding") occurred prior-to, during, and following the egg-laying period. Following the laying of the second egg, courtship feeding rates declined significantly. There was a significant, positive correlation bebween courtship feeding rates and subsequent chick feeding rates by males. The incubation rates of females were significantly higher than those of males, especially during the first ten days of incubation. Territorial attendance rates during the incubation stage were similar for males and females. During the chick stage, territorial attendance rates of females were significantly higher than those of males. The size of fish fed to chicks by males increased as the chicks grew older and chick feeding rates of males were approximately three times higher than female rates. Based on these quantitative differences in parental care activities, the cumulative parental time investment by the two sexes was very similar. However, the energetic investment by males was likely greater than that by females, since male parental contributions (e.g. courtship feeding and chick feeding) often entailed extensive foraging behaviour.

Partial characterization of the cloned dihydrofolate reductase gene of Saccharomyces cerevisiae

The cloned dihydrofolate reductase gene of Saccharomyces cerevisiae (DFR 1) is expressed in Escherichia coli. Bacterial strain JF1754 transformed with plasmids containing DFR 1 is at least 5X more resistant to inhibition by the folate antagonist trimethoprim. Expression of yeast DFR 1 in E. coli suggests it is likely that the gene lacks intervening sequences. The 1.8 kbp DNA fragment encoding yeast dhfr activity probably has its own promotor, as the gene is expressed in both orientations in E. coli. Expression of the yeast dhfr gene cloned into M13 viral vectors allowed positive selection of DFR 1 - M13 bacterial transfectants in medium supplemented with trimethoprim. A series of nested deletions generated by nuclease Bal 31 digestion and by restriction endonuclease cleavage of plasmids containing DFR 1 physically mapped the gene to a 930 bp region between the Pst 1 and Sal 1 cut sites. This is consistent with the 21,000 molecular weight attributed to yeast dhfr in previous reports. From preliminary DNA sequence analysis of the dhfr DNA fragment the 3' terminus of DFR 1 was assigned to a position 27 nucleotides from the Eco Rl cut site on the Bam Hi - Eco Rl DNA segment. Several putative yeast transcription termination consensus sequences were identified 3' to the opal stop codon. DFR 1 is expressed in yeast and it confers resistance to the antifolate methotrexate when the gene is present in 2 - 10 copies per cell. Plasmid-dependent resistance to methotrexate is also observed in a rad 6 background although the effect is somewhat less than that conferred to wild-type or rad 18 cells. Integration of DFR 1 into the yeast genome showed an intermediate sensitivity to folate antagonists. This may suggest a gene dosage effect. No change in petite induction in these yeast strains was observed in transformed cells containing yeast dhfr plasmids. The sensitivity of rad 6 , rad 18 and wild-type cell populations to trimethoprim were unaffected by the presence of DFR 1 in transformants. Moreover, trimethoprim did not induce petites in any strain tested, which normally results if dhfr is inhibited by other antifolates such as methotrexate. This may suggest that the dhfr enzyme is not the only possible target of trimethoprim in yeast. rad 6 mutants showed a very low level of spontaneous petite formation. Methotrexate failed to induce respiratory deficient mutants in this strain which suggested that rad 6 might be an obligate grande. However, ethidium bromide induced petites to a level approximately 50% of that exhibited by wild-type and rad 18 strains.

Participation of registered nurses in continuing education

This correlational study investigated the psychological types, learning style preferences, readiness for self-directed learning, demographic and continuing education participation data of 154 registered nurses at two different Southern Ontario hospitals. One hospital was a large tertiary care university-affiliated teaching centre (Cityview) and the other was a smaller secondary care community hospital (Waterview). The instruments used in the study were the PET Type Check, Kolb's Learning Style Inventory, the Self-Directed Readiness Scale (SDLRS), and a Nursing Survey developed by the researcher. Descriptive statistics, crosstabulations and correlational analyses were calculated. The most common psychological types identified among this sample of nurses were extraverted thinking, introverted intuitive and extraverted intuitive. There were no significant differences between the two hospitals. The accommodator learning style was preferred overall, with more nurses at Waterview Hospital preferring the diverger learning style, and more nurses at Cityview Hospital preferring the accommodator learning style. The majority of nurses scored in the average and above average categories on the SDLRS, indicating that they perceive themselves as ready to engage in self-directed learning. At Cityview Hospital there were more nurses in the average and high readiness categories, whereas at Waterview Hospital more nurses scored in the below average category. No significant correlations were found for learning style with psychological type, or for learning style with SDLRS scores. A positive correlation was found to exist between SDLRS scores and each of the psychological types extraverted feelings, extraverted thinking, and introverted intuitive.The only significant correlation for psychological type and continuing education activity was a positive correlation between extraverted thinking types and participation in informal discussion or study groups. Positive correlations were found for SDLRS scores with each of the following continuing education activities; number of hours per month spent reading journals; journal reading; attendance at credit courses; watching videos; using reference texts. Further details of the results are included as well as a discussion of the findings and implications for future research.

Partnership, politics and public administration: a case study of the Ontario Ministry of Natural Resources

Efforts to reform the public sector reflect the social, political and economic environment within which government must function. The recent demands by the public for more consensual decision-making, as well as more efficient, effective and responsive public service, have resulted in a number of reform initiatives, including an emphasis on partnership development. The purpose of this thesis is to examine partnership arrangements within the public sector. Specifically, the thesis will assess the value of partnerships and their impact on government by examining six partnership arrangements involving the Ontario Ministry of Natural Resources (OMNR). The OMNR, having recently been awarded the 1992 Institute of Public Administration of Canada Award for Innovative Management, on the theme of partnership development, is being lauded as an example for other government agencies considering similar alliances. The thesis begins by introducing the concept and practice of partnership within the public sector in general and the OMNR specifically. Descriptive analysis of six OMNR partnerships is provided and a number of criteria are used to determine the success of each of these arrangements. Special attention is paid to the political implications of partnerships and to those attributes which appear to contribute to the successful establishment and iii maintenance of partnership arrangements. The conclusion is drawn that partnerships provide the government with an opportunity to address public demands for greater involvement in decision-making while accommodating government's limited financial resources. However, few truly collaborative partnerships exist within the public sector. There are also significant political implications associated with partnerships which must be dealt with both at the political and bureaucratic levels of government. Lastly, it is argued that while partnerships within the OMNR are experiencing some difficulties, they constitute a genuine attempt to broaden the base of decision-making and to incorporate the concerns of stakeholders into resource management.

Patterns of faunal change at an upper Cambrian trilobite extinction event, Nolichucky Formation, Tennessee and Virginia

During the Upper Cambrian there were three mass extinctions, each of which eliminated at least half of the trilobite families living in North American shelf seas. The Nolichucky Formation preserves the record of one of these extinction events at the base of the Steptoean Stage. Sixty-six trilobite collections were made from five sections In Tennessee and Virginia. The lower Steptoean faunas are assigned to one low diversity, Aphelaspis-dominated biofacies, which can be recognized in several other parts of North America. In Tennessee, the underlying upper Marjuman strata contain two higher diversity biofacies, the Coosella-Glaphyraspis Biofacies and the Tricrepicephalus-Norwoodiid Biofacies. At least four different biofacies are present in other parts of North America: the Crepicephalus -Lonchocephalus Biofacies, the Kingstonia Biofacies, the Cedaria Biofacies, and the Uncaspis Biofacies. A new, species-based zonation for the Nolichucky Formation imcludes five zones, three of which are new. These zones are the Crepicephalus Zone, the Coosella perplexa Zone, the Aphelaspis buttsi Zone, the A. walcotti Zone and the A. tarda Zone. The Nolichucky Formation was deposited within a shallow shelf basin and consists largely of subtidal shales with stormgenerated carbonate interbeds. A relative deepening is recorded In the Nolichucky Formation near the extinction, and is indicated In some sections by the appearance of shale-rich, distal storm deposits above a carbonate-rich, more proximal storm deposit sequence. A comparable deepening-upward sequence occurs near the extinction in the Great Basin of southwestern United States and in central Texas, and this suggests a possible eustatic control. In other parts of North America, the extinction IS recorded In a variety of environmental settings that range from near-shore to slope. In shelf environments, there is a marked decrease in diversity, and a sharp reduction in biofacies differentiation. Although extinctions do take place in slope environments, there IS no net reduction in diversity because of the immigration of several new taxa.

Perceptions of leadership in adolescent girls, members of the Girl Guides of Canada

Twenty-eight young women who were members of the Girl Guides of Canada as Rangers and Cadets from a convenience sample chose to participate in this case study. They were from four separate locations in Southern Ontario. The interviews and observations at unit meetings allowed an indepth look into the perceptions of leadership of these young women. The amount of time observing and interacting with each participant provided a snapshot of what they thought and how they responded to the questions asked at that particular time. Each girl responded to the question, "Are you a leader?" They then gave examples of their own leadership and described leaders they knew. Their responses are reported in relation to their definitions. Their identifications of effective and ineffective leaders were examined, as well as their views of the best and worst things a leader can do. This information is reported by unit, as some patterns in their responses emerged which were unique to each group. The responses of all of the girls to the leadership of Guiders, Rangers and Cadets and the hypothetical effect of male leaders and male Rangers in Guiding are reported. For these, the participants' views were sorted based on the common themes/ and regardless of their group affiliation, since many of the same themes emerged when examining these questions. The information collected was extensive and allowed for trends and parallels to become evident 0 All of the participants identified themselves as leaders. A diversity of views exists in their perceptions of leadership. For many, age makes a difference in leadership. The majority identified the single-sex aspect of the organization as comfortable and stated that it should remain so. Gender profoundly affects who is listened to and what opportunities are available.

Permissivity of human HeLa cells to bovine adenovirus type 2 (BaV2 infection

Infection of hUlnan cells by bovine adenovirlls type 2 (BAV2) is abortive. To obtain a better understanding of this pllenomel1011, and in particular to identify Wllich steps in the viral replicative cycles are altered dllring this virlls-host cells interaction, we have llndertaken a detailed study of BAV2 infections of the nonpennissive hUlnan IIeLa cells. Using autoradiography and 3H-thymidine-labeled vvhole virus particles for infection of HeLa cells, vve determined that viral attachluent appears normal. Furthermore, Southern analysis revealed that internalization and transport to the nuclells occurs in BAV2 infected HeLa cells. To investigate viral DNi\ synthesis, infectivity assays involving hydroxyllrea, a viral DN-A synthesis inhibitor, were carried out. The results revealed that Bft:LV2 DNA synthesis does not occur in HeLa cells. Fllrtller investigations into viral early gene expression by northern blotting analyses indicated that HeLa cells fail to support expression of EIA. This suggested that abortive infection by BAV2 could be attributed to faiiure of EIA to express. To test the possibility that the failure to express ElA was due to the inability of the host cell to recognize the E lA prOlTIoter, ,ve carried out transient expression transfection experiments using plaslnids \vith the bacterial lacZ linder the control of either BAV2 or i\d5 EIA promoter. X-gal histochelIlical assays sho\ved expression of lacZ from the Ad5 ElA prOlnoter but no expression of lacZ [rOln the BAV2 EIA prOlTIoter. This further suggests that the abortive infection b:y BAV2 could be attributed to failure of EIA to express dlle to a nonfllnctional prOlTIoter in hlunan cells. Thus we speClllated that abortive infection of HeLa cells by adenoviruses may be averted by providing EtA functions in trans. To demonstrate this, we coinfected HeLa cells with Ad5 and BAV2, reasoning that Ad5 could cOlnpensate for EIA deficiency in BAV2. OUf results showed that BAV2 DNA synthesis was indeed Sllpported in HeLa cells coinfected with Ad5dlE3 as revealed by Southern analysis. In contrast, coinfection of HeLa cells \vith BAV2 and Ad5dlElE3 mutallt did not support BLt\V2 DNA synthesis. Interestingly, BAV2 failed to replicate in 293 cells which are constitlltively expressing the El genes. This could ilnply that El is necessary but not sufficient to avert the failllre ofBAV2 to undergo productive infection ofhulnan cells.