bluuebunny/crossref_metadata_2025 huggingface dataset:
Field measurements of n-factors for natural forest areas, Mackenzie Valley, Northwest Territories
Authors: Taylor A E
Published: September 2013

The n-factor is defined as the ratio of the ground surface index of seasonal thawing (or freezing) to the air index of seasonal thawing (or freezing). Equivalently, the n-factor relates mean seasonal ground surface temperatures to the more readily available mean
air temperatures. In geotechnical engineering calculations, the n-factor for a phase change season is a single parameter that represents the complex process of heat transfer through vegetation and snowcover. In 1993-94, the GSC established a latitudinal transect along the Mackenzie River valley
using inexpensive miniature data loggers to record air and ground temperatures. N-factors calculated from the first year of data reflect the diverse forest, vegetation, and snowcover. Freezing season n-factors are lower because of the attenuation effect of snow, in addition to that of vegetation.
N-factors may be used in quantitative permafrost mapping and climate change-permafrost impact prediction.
Thermal history and petrology of wood and other organic inclusions in kimberlite pipes at Lac de Gras, Northwest Territories
Authors: Stasiuk L D , Nassichuk W W
Published: September 2013

Dispersed peatified to coalified wood and other macerals within the crater and diatreme facies of kimberlite pipes at Lac de Gras have been studied using reflected light microscopy. The coalification levels fall into two categories: i) cellulose-bearing, lignitic
peat (<0.20 %Ro); and ii) lignite to sub-bituminous (0.33-0.44 %Ro). The latter are from the diatreme facies whereas most of the low rank samples are from the crater facies. The average temperature of lignitic peat never exceeded 30°C. Huminite from the diatreme facies was
subjected to higher temperatures but none of the huminites display microscopic features attributable to pyrometamorphism. If the wood in the diatreme is primary, a short heating event (about 100°C) may have enhanced coalification without altering peat in the crater facies. Alternatively, if
huminite in the diatreme represents pre-intrusion burial, coalification and pre-Paleocene erosion may have occurred. The preservation of primary, asphalt bitumen supports a maximum temperature of less than 110°C.
Stress orientation indicators (neotectonic plucking fractures) in bedrock of glacier forefields, southeastern Cordillera, western Canada
Authors: Bell J S , Eisbacher G H
Published: September 2013

Polished surfaces of glacier forefields in the southeastern Canadian Cordillera display plucking fractures that are distinctly oblique to glacial striae. They commonly show preferred orientation in each forefield, and formed by basal glacier shearing and opening
of extension fractures. We interpret these incipient fractures as signals of stress release during downwasting of glaciers and suggest that they are oriented parallel to SHmax.
Characteristics of the Taconic orogenic front, northeastern Quebec Appalachians
Authors: Lynch G
Published: September 2013

In 1997, four high-resolution, regional aeromagnetic surveys totalling 168 917 line kilometres were flown over Baffin Island, southern Saskatchewan, and northern British Columbia. One of these surveys was funded by private industry, the Geological Survey of
Canada provided complete funding for two surveys, and one survey was cost-shared by the Geological Survey of Canada and partners. One detailed helicopter-borne electromagnetic/magnetic/gamma-ray spectrometric survey totalling 10 632 line kilometres was flown in New Brunswick. This survey was funded
by the Province of New Brunswick. The program to level the Canadian aeromagnetic profile data set, for the elimination of survey boundary effects, proceeded with drape computation and levelling of surveys flown at constant altitude in British Columbia and western Alberta. An aeromagnetic/gamma-ray
spectrometric survey flown in Guinea West Africa has been supervised by the Geological Survey of Canada.
Along-strike Upper Cambrian-Lower Ordovician stratigraphic nomenclature and framework for the external Humber Zone, from Quebec City to Gaspé
Authors: Lavoie D
Published: September 2013

The Upper Cambrian-lowermost Ordovician succession in the Humber Zone (eastern Quebec) is a coarse-grained interval that contrasts with adjacent stratigraphic units. Our understanding of this interval is hampered by a complex stratigraphic framework that reflects
the local perspective of previous studies as well as depositional facies variations. The name 'Trois-Pistoles Group' is proposed for this succession. At the base of the succession, the Saint-Damase Formation consists of limestone conglomerate and thickly bedded arkosic sandstone and overlies
fine-grained siliciclastic rocks of the Saint-Roch and l'Orignal formations. The Saint-Damase Formation is overlain by a succession of turbidite (Ladrière Formation and upper part of the Lauzon and Grosses-Roches formations), mudrock (Rivière-du-Loup Formation), and quartzite (Kamouraska
Formation). The upper part of the succession reflects facies zonation developed on the continental slope after the major lowstand recorded in the Saint-Damase Formation.
Electrical characteristics of mineralized and nonmineralized rocks at the Caribou deposit, Bathurst mining camp, New Brunswick
Authors: Katsube T J , Connell S , Scromeda N , Goodfellow W D , Best M E
Published: September 2013

Electrical anisotropic (l) characteristics of ten mineralized (massive sulphides) and non-mineralized (foliated volcanic tuffs) rock samples from the Caribou deposit (Bathurst mining camp, New Brunswick) have been studied to provide information to assist
interpretation of airborne, ground, and borehole EM surveys.
Results indicate that electrical resistivities (rr) of massive sulphides and foliated volcanic tuffs fall within the ranges 0.1-3.0 W-m and 1.5x102-4.6x104 W-m, respectively. Little anisotropy is seen in the massive suphides, except for those with calcitic veins cutting across the sample, which
increase rr by 6-390 times (l=6:1 to 390:1) in the direction perpendicular to the vein compared to values obtained where no veins are present. The volcanic tuffs display high and low rr values: 6800-15 000 W-m and 150-2700 W-m, in the directions perpendicular and parallel to the foliation, resulting
in respectively, values of l ranging from 4:1 to 70:1. Petrological characteristics which can explain the low rr values are thin layers containing high concentrations of chloritic material.
Shale permeability and its relation to pore-size distribution
Authors: Katsube T J , Issler D R , Cox W
C
Published: September 2013

Shales are characterized by unimodal pore-size distributions. The relationship between shale permeability (k) and the mode (dm) of these distributions has been investigated, for 22 tight shale samples from Canadian offshore and interior regions, to determine the
degree of accuracy and reliability of using dm to estimate shale permeability. Such an attempt is made, using an indirect method, because tight shales represent some of the lowest permeabilities (10-22 m2 to 10-19 m2) and are extremely difficult to measure.
Results indicate that, although a considerable scatter exists for k plotted against dm, a relationship of significance exists. Estimates of k using dm are within one order of magnitude of the measured values for 90% of the data, and within a factor of 3 for 65% of the data, using the
equation:

k = 10-21exp(0.13dm - 0.68) m2

Improved estimates of k may result from a better understanding of the role of other pore-structure parameters.
Extraction chimique des éléments du groupe du platine et de l'or et détermination de leurs teneurs par spectrométrie de masse à émission de plasma
Authors: Gueddari K , LaFlèche M R , Amossé J
Published: September 2013

We have developed a chemical analysis method for platinum group elements and gold. We start by fusing rock samples with sodium peroxide. After reduction with stannous chloride, PGE and Au are extracted by coprecipitation using selenium and tellurium as carriers.
Yields approach 100%. The analysis is carried out by ICP-MS to improve detection limits. Instrumental operating conditions, mass interference, internal standards, and calibration are discussed. The results obtained for international standards are generally in good agreement with the proposed
values. The method presented here can be used for samples that are either poor or rich in PGE and Au and is currently been used for PGE and Au determinations in mafic and ultramafic rocks.
Evaluation of a Russian-designed borehole resistivity probe based on a capacitive principle
Authors: Bristow Q , Mwenifumbo C J
Published: September 2013

A new type of resistivity probe, based on the principle of electrical capacitance, has been designed by Russian scientist V.M. Timofeev of the All-Russia Institute of Hydrology and Engineering Geology, Moscow. A prototype version was built under a collaborative
project funded jointly by the Geological Survey of Canada and IFG Corporation, a Canadian manufacturer of borehole geophysical instrumentation. The Geological Survey of Canada carried out field tests at its borehole test facilities in Ottawa and at the New Calumet massive sulphide deposit, Quebec.
The capacitive resistivity data were compared to the galvanic resistivity and inductive conductivity data. Preliminary results indicate that the capacitive technique is sensitive in the resistivity range 100-10 000 W.m and compares well with galvanic and inductively measured resistivities. Field
tests were also carried out for several transmitter-receiver spacings and in plastic-cased fluid-filled boreholes. Capacitive resistivity logs acquired in plastic-cased boreholes are almost identical to those acquired in uncased boreholes and therefore, promise to be valuable logs for use in
environmental applications where boreholes drilled in unconsolidated sediments often have plastic casing.
Investigating brand romance, brand attitude and brand loyalty in the cellphone industry
Authors: Kruger Liezl-Marié , Kühn Stefanie W. , Petzer Daniel J. , Mostert Pierre G.
Published: September 2013

Orientation: Fast growth and intense competition characterise the South African cellphone industry. Customers switch easily between cellphone brands and marketers are challenged to cultivate brand relationships with customers in order to ensure brand loyalty.Research purpose: This study investigated the brand romance, -attitude and -loyalty of customers toward their cellphone brands in the North West Province, South Africa.Motivation for the study: One way in which brand loyalty in the cellphone industry can be achieved is to influence attitudes and, ultimately, create brand loyalty by promoting brand romance between the customer and the brand.Research design, approach and method: Being quantitative in nature, the study followed a descriptive research design to collect 371 responses through self-administered questionnaires.Main findings: The results indicated that most respondents were contract customers who only use a brand of cellphone for between one and three years. Brand romance toward cellphone brands was positive although room for improvement exists. Brand attitude toward current cellphone brands was also positive, but brand loyalty was fairly low, indicating that marketers need to improve brand loyalty toward their cellphone brand. There were, furthermore, significant and positive relationships between brand romance, brand attitude and brand loyalty toward cellphone brands.Practical/managerial implications: Brand romance can be considered to be a viable way of improving attitude toward a cellphone brand, ultimately leading to brand loyalty.Contribution/value-add: Brand romance in brand relationships has significant and positive relationships with brand attitude and brand loyalty in the cellphone industry of South Africa.
Comprehensibility, manageability and meaningfulness at work: Construct validity of a scale measuring work-related sense of coherence
Authors: Vogt Katharina , Jenny Gregor J. , Bauer Georg F.
Published: September 2013

Orientation: Work-related sense of coherence (Work-SoC) is defined as the perceived comprehensibility, manageability and meaningfulness of an individual’s current work situation.Research purpose: The aim of the present study was to investigate the factorial invariance and the construct validity of a scale that measures Work-SoC.Motivation for the study: It might be useful to specifically apply the concept of sense of coherence to the work context.Research design, approach and method: Statistical analysis was performed on crosssectional (n = 3412) and longitudinal (n = 1286) questionnaire data collected in eight medium to large Swiss companies from diverse economic sectors (four industrialproduction companies, one food-processing company, one public-administration service and two hospitals). The dataset therefore covers a broad range of different occupational groups.Main findings: Multiple-group analyses indicated that the scale’s factor structure remains invariant across different employee groups and across time. High values in job resources were related to high values in Work-SoC whereas high values in job demands were related to low values in Work-SoC. Furthermore, Work-SoC acted as a partial mediator between job resources and work engagement.Practical/managerial implications: It can be concluded that Work-SoC might serve as a practical screening instrument for assessing an employee’s perception of the potential health-promoting qualities of his or her current work situation.Contribution/value-add: The study advances both the salutogenic theory and the field of positive occupational health psychology by redefining sense of coherence as an interactional and context-specific construct that is useful for intervention research.
Effect of psychological capital and resistance to change on organisational citizenship behaviour
Authors: Beal III Loyd , Stavros Jacqueline M. , Cole Matthew L.
Published: September 2013

Orientation: Research in positive organisational behaviour shows that positive psychological capital (PsyCap) is a construct that enables self-efficacy, optimism, hope and resilience to succeed in the workplace and that employee resistance to change is a key barrier to organisational change.Research purpose: This study examined the possible role of resistance to change as a moderator of the predictive relationship between PsyCap and organisational citizenship behaviour (OCB), in which OCB served as an index for measuring positive organisational change.Motivation for the study: Little empirical research has investigated the application of positive organisational behaviour to government organisations undergoing organisational change. Organisations can use the study results to increase positive outcomes and reduce resistance in government organisations experiencing a holistic change intervention.Research design, approach and method: The data comprised a cross-sectional survey of 97 employees from a government organisation that provides life-cycle career management support. Employees completed the 24-item psychological capital questionnaire, the 16-item organisational citizenship behaviour scale and the 17-item resistance to change scale. Data analyses used a mixed methods approach to merge quantitative inferential statistics with qualitative thematic analysis.Main findings: The quantitative analysis yielded high levels of resistance to change that moderated the positive effect of PsyCap on organisational citizenship behaviour. The thematic analysis revealed that affective, behavioural and cognitive forms of resistance to change were prevalent.Practical/managerial implications: Organisational leaders should seek to reduce resistance and increase the resources that organisations need to effect positive organisational change.Contribution/value-add: This study adds to the growing body of knowledge about positive organisational behaviour in government organisations.
Die stand van die Gereformeerde kerkreg
Authors: Botha C. J.
Published: September 2013

The stance of Reformed church polityThe author deals with the resistance against the study of church polity and stresses its necessity. He sketches the development in Protestant church polity, and then investigates the fact that the confessions function as the paradigm for a particular church. The problem with the reformed confessions is that they are based on sixteenth century exegesis. Consequently there is a growing rift between church polity and the Biblical disciplines. He argues for a debate on the issue of the reformulation of the reformed confessions, and that Mt 28:18-20 be the Scriptural "sitz im leben" of church polity and not 1 Cor 14:40.
Enkele opmerkinge oor die gewete
Authors: Heyns J. A.
Published: September 2013

Some remarks on conscienceThe phenomenon of the human conscience has been not only the object of penetrating analysis through the centuries, but also a highly abused human faculty. The question can be asked: is conscience concerned only with man’s relation to himself, or also with man’s relation to Cod and to other men and even to institutions such as the state and the church? To certain people conscience pretends to be the voice of God within them and therefore the standard for the relation to other men. But in this case man himself became God.
’n Nuwe hoofstuk in die verhouding tussen Franse Protestante en Suid-Afrika: Die Collogue L’Afrique du Sud en transition, Parys, 15–16 Januarie 1993
Authors: Meiring P. G. J.
Published: September 2013

A new chapter in the relationship between French Protestants and South Africa: The Colloque l’Afrique du Sud en transition, Paris, 15–16 January, 1993Early in 1993 an important colloquium, called together by the Federation of Protestants in France, (FPF) in conjunction with DEFAP, the missionary secretariate of the FPF, on South Africa in transition, was held in Paris. The colloquium had a fourfold purpose: to inform the French public on recent developments in South Africa; to explain the difficult problems awaiting solutions in that country; to rebuild contact between churches in South Africa and France; and to identify lessons France, as well as the wider world, may learn from the South African experience. Speakers from both South Africa and France were invited to address the colloquium. In the article some of the views expressed at the colloquium are summarised and evaluated. In an introductory paragraph the role and the influence of Protestants in France today are briefly touched upon.
Teologie en etiek in die brief aan Filemon: ’n Poging tot verantwoording
Authors: Roberts J. H.
Published: September 2013

Theology and ethics in the letter to Philemon: An attempt at giving an accountThe criticism levelled by Smit against the attempts of New Testament scholars to treat the ethics of the books of the New Testament are dealt with under the headings of "ethos and ethics"; "Biblical ethics"; "the tasks of New Testament ethics"; and "the teaching of the Bible". In order to give an account of the work done by New Testament scholars the ethics of Paul in the letter to Philemon is discussed After a brief summary of the argument of Philemon, the request of this letter is analysed from the viewpoint of ethical argumentation, concluding with remarks on theology and ethics in Philemon.
The glory-motif in John 17:1-5: An exercise in Biblical semantics
Authors: Van der Merwe D. G.
Published: September 2013

In John 17:1-5 a Greek noun occurs once and the verb four times. They are consequently translated as ‘glory’ and ‘glorification’ in various Bible translations. This research is an attempt to determine the various perspectives and possible semantic meanings respectively of these words in order to suggest meaningful alternatives that could be used in a dynamic-equivalent or periphrastic translation. The methodology followed is: first a look at a few lexical meanings, and an investigation of the textual and theological contexts in order to help determine the basic semantic fields of these words, followed by a more detailed examination to aid a more specific interpretation.
Collection stewardship constrained by resources: The management of religious archives in Pietermaritzburg, KwaZulu-Natal region
Authors: Garaba Francis
Published: September 2013

A survey using questionnaires, observation and interviews was conducted in 2011 to ascertain the collection stewardship strategies of archival repositories with religious archives in Pietermaritzburg. The study concluded that there was a need to establish a religious archives group in order for the voice of ecclesiastical archives to resonate across South Africa. Through this group, it is hoped that there will be greater coordination and networking amongst the archival repositories. The help of associations such as the South African Society of Archivists, the Oral History Association of South Africa and the South African Preservation Group could greatly assist in fostering best practices in archival management. To champion this worthwhile cause, it would be ideal to come up with an Open Day on religious archives to serve as an advocacy platform. These recommendations are made against a backdrop of the poor state of religious archives in Pietermaritzburg, resulting from acute underfunding and which threatens the survival of this record in the long term.
Gedragswetenskaplike dimensies in die Praktiese Teologie: 'n bedryfsielkundige perspektief
Authors: Coetzee J. J. L.
Published: September 2013

Die klem in die bestuur van mense het oor die afgelope drie dekades vinnig verskuif van 'n meganistiese na 'n humanistiese benadering. Die gedragswetenskap as fundamentele onderbou vir algemene bestuur geniet al hoe meer klem veral in die Suid-Afrikaanse heterogene bestel.
Riglyne uit die verlede vir die sendingwerk van die toekoms
Authors: Cronj J. M.
Published: September 2013

Wanneer daar dan oor "riglyne" uit die verlede vir die sendingwerk van die "toekoms" gehandel word, is dit ’n riskante onderneming. Te meer nog as gevolg van skrywer se noue kontak met die buitelandse sending van die Ned. Geref. Kerk, wat sy objektiwiteit mag beïnvloed. Te midde van die risiko's daaraan verbonde en met vermyding van bogenoemde slaggate so ver moontlik, wil ons tog probeer om sekere riglyne te trek wat moontlik ook rigtinggewend vir die uitgebreide sendingwerk van die Kerk in die toekoms kan wees.
Het geheim van de Messias bij Josephus
Authors: Middendorp T.
Published: September 2013

Heeft Josephus kennis gehad van de jonge christelijke kerk? Wat wist hij van Jezus van Nazareth? Kan hij als getuige voor de historiciteit van Jezus aangehaald worden? Dit zijn oude vragen. Hier wordt opnieuw een antwoord gezocht-niet op grond van een bepaalde tekst van deze schrijver - maar met behulp van het kader van diens wereldbeschouwing, die in het geheel van zijn oeuvre tot uitdrukking komt.
Martin Luther se beskouing van die ekumene met verwysing na die komtemporere situasie binne die Federasie van Evangelies-Lutherse Kerke in Suider-Afrika
Authors: Beyers G. J.
Published: September 2013

"Hulle leer dat die een heilige Kerk vir ewig sal voortbestaan. Hierdie kerk is die vergadering van die gelowiges waarbinne die Evangelie korrek geleer en die sakramente reg bedien vord. Vir die eenheid van die Kerk is dit voldoende om eenheid van geloof te hê met betrekking tot die leer van die Woord en die bediening van die sakramanete. Dit is nie nodig dat dieselfde mens like tradisies, ritusse en sereraonies orals geleer vord nie." (Augsburgse Konfessie. Artikel 7).
Tyd en omstandigheid, metode en skrifbeskouing in ’n blik op die 1933-vertaling
Authors: Oberholzer J. P.
Published: September 2013

Oor to Bybelvertaling wat vir 50 jaar in gebruik was en bowendien die eerste volledige Afrikaanse Bybelvertaling was, kan ’n mens nie anders as om met groot deernis te praat nie. Ook die opdrag om krities na hierdie vertaling te kyk en op sy gebreke te wys, neem die deernis nie weg nie.
Syrian field hospitals: A creative solution in urban military conflict combat in Syria
Authors: Sankari Abdulghani , Atassi Basel , Sahloul Mohammed Zaher
Published: September 2013

Since the war started in Syria nearly two years ago several independent organizations reported the use of medicine as a weapon by the Syrian authorities, killing of doctors and arresting patients who were admitted to the hospitals for treatment. In year 2012 the World Health Organization (WHO) found nearly 50% of hospitals are not functioning due to lack of staff, equipment and medicine. This report highlights how the doctors in Syria are creative and courageous to risk their own lives to save thousands of innocent lives.
Residual weeds in winter wheat in Manitoba
Authors: Cavalieri Andrea , Lewis Derek W. , Gulden Robert H.
Published: September 2013

Cavalieri, A., Lewis, D. W. and Gulden, R. H. 2013. Residual weeds in winter wheat in Manitoba. Can. J. Plant Sci. 93: 1195–1200. Winter wheat production has increased from a few thousand to several hundred thousand acres in Manitoba over the past decade. In the summer of 2009, a mid-season weed survey was conducted to establish a benchmark of the residual weed community in winter wheat in three ecoregions in Manitoba. Field histories and herbicide management practices were also recorded for all 84 fields surveyed. Traditionally important weeds in other field crops such as green foxtail [Setaria viridis (L.) Beauv.], wild oats (Avena fatua L.) and wild buckwheat (Polygonum convolvulus L.) were also the most abundant weeds in winter wheat. A species never observed in production fields, waterpod [Ellisia nyctelea (L.) L.] was documented. Neither Japanese brome grass (Bromus japonicum L.) nor downy brome (Bromus tectorum L.), winter annuals often prevalent in winter wheat, were found.
Swainson hard red winter wheat
Authors: Fowler D. B.
Published: September 2013

Fowler, D. B. 2013. Swainson hard red winter wheat. Can. J. Plant Sci. 93: 1257–1259. Swainson is a medium tall, high-yielding, stem and leaf rust resistant winter wheat (Triticum aestivum L.) that is registered for production in western Canada. It is a hard red winter wheat cultivar that is eligible for grades of the Canada Western General Purpose (CWGP) wheat class, which was created in 2008 to encourage the development of cultivars to fill the high energy demands of the biofuel and livestock feed markets in western Canada. Its high yield potential has been particularly evident on dry land in Saskatchewan where its grain yield was 116% of CDC Buteo, the Canada Western Red Winter Wheat Class grain quality check cultivar, and 110% of Accipiter and 117% of CDC Falcon, the high-yielding check cultivars. High grain yield potential of low protein concentration grain and rust resistance make Swainson a good fit for the CWGP class.
Review: Improving nitrogen use efficiency of potted chrysanthemum: Strategies and benefits
Authors: MacDonald William N. , Blom Theo J. , Tsujita M. James , Shelp Barry J.
Published: September 2013

MacDonald, W. N., Blom, T. J., Tsujita, M. J. and Shelp, B. J. 2013. Review: Improving nitrogen use efficiency of potted chrysanthemum: Strategies and benefits. Can. J. Plant Sci. 93: 1009–1016. Floricultural greenhouse operations can pose significant environmental risk due to the leaching and runoff of nutrients such as [Formula: see text]. To face this challenge, Ontario growers have adopted recirculating systems, such as the subirrigated “ebb and flow” system, on benches, troughs and concrete floors. Chrysanthemum (Chrysanthemum morifolium Ramat.) is the most commonly grown floricultural greenhouse crop species in the world and the potted type is well adapted to subirrigation. Reduction of N fertilization towards the end of the crop cycle is generally recommended to improve the shelf life of cut and potted plants, but it is uncertain how this practice influences the N status of the plant and the electrical conductivity of the growing medium. In this review, we discuss N use efficiency and strategies for managing the [Formula: see text] status of plants, and then propose that this knowledge can help to improve the N use efficiency of potted chrysanthemum grown with subirrigation under greenhouse conditions.
Constructive Proof of the Carpenter's Theorem
Authors: Bownik Marcin , Jasper John
Published: September 2013

We give a constructive proof of the carpenter’s theorem due to Kadison. Unlike the original proof, our approach also yields the real case of this theorem.
The Surgical Residency Baby Boom: Changing Patterns of Childbearing During Residency Over a 30-Year Span
Authors: Smith Caitlin , Galante Joseph M. , Pierce Jonathan L. , Scherer Lynette A.
Published: September 2013

Background

Birthrates during surgical residency appear to be rising. One assumption is that this is due to changes in the structure of surgical residencies.

Objective

The purpose of our study was to explore whether an increase in birthrates has occurred and the reasons for this.

Methods

We conducted an anonymous survey of current residents and alumni from 1976 to 2009 at a single university-based surgery training program.

Results

Alumni (46 of 116) and current residents (38 of 51) were surveyed, and our response rate was approximately 50% (84 of 167). Respondents were grouped into cohorts based on their residency start year. The early cohort consisted of residents starting residency between 1976 and 1999, and the late cohort consisted of residents starting residency between 2000 and 2009. The percentage of male residents with children during residency training was similar for the early and late cohorts (34% [10 of 29] versus 41% [9 of 22]). For female residents, there was a substantial increase in childbearing for the late cohort (7% [1 of 15] versus 35% [6 of 18]). Fifty-two percent (44 of 84) of the respondents who had children during residency reported that work hours and schedule had a negative effect on their decision to have children. Most respondents reported that availability or cost of child care, impact on residency, support from the program, increased length of training, or availability of family leave did not factor as concerns.

Conclusions

Childbearing during residency has increased in female residents in our study. Surgical residency programs may need to accommodate this change if they want to continue to recruit and retain talented residents.
Comparison of Galvanic Corrosion Potential of Metal Injection Molded Brackets to that of Conventional Metal Brackets with Nickel-Titanium and Copper Nickel-Titanium Archwire Combinations
Authors: Chidambaram S , Vijay M , Varma D Praveen Kumar , Reddy K Baburam , Ravindranath D , Prasad M Rajendra
Published: September 2013

Aim

The aim of the study is to investigate the galvanic corrosion potential of metal injection molding (MIM) brackets to that of conventional brackets under similar in vitro conditions with nickel-titanium and copper nickel-titanium archwires.

Materials and methods

Twenty-five maxillary premolar MIM stainless steel brackets and 25 conventional stainless steel brackets and archwires, 0.16 inch, each 10 mm length, 25 nickeltitanium wires, 25 copper nickel-titanium wires were used. They were divided into four groups which had five samples each. Combination of MIM bracket with copper nickel-titanium wire, MIM bracket with nickel-titanium wire and conventional stainless steel brackets with copper nickel-titanium wire and conventional stainless steel brackets with nickel-titanium wires which later were suspended in 350 ml of 1 M lactic acid solution media. Galvanic corrosion potential of four groups were analyzed under similar in vitro conditions. Precorrosion and postcorrosion elemental composition of MIM and conventional stainless steel bracket by scanning electron microscope (SEM) with energy dispersive spectroscope (EDS) was done.

Results

MIM bracket showed decreased corrosion susceptibility than conventional bracket with copper nickeltitanium wire. Both MIM and conventional bracket showed similar corrosion resistance potential in association with nickel-titanium archwires. It seems that both brackets are more compatible with copper nickel-titanium archwires regarding the decrease in the consequences of galvanic reaction. The EDS analysis showed that the MIM brackets with copper nickel-titanium wires released less metal ions than conventional bracket with copper nickeltitanium wires.

Conclusion

MIM brackets showed decreased corrosion susceptibility, copper nickel-titanium archwires are compatible with both the brackets than nickel-titanium archwires.

Clinical significance

Clinically MIM and conventional brackets behaved more or less similarly in terms of corrosion resistance. In order to decrease the corrosion potential of MIM brackets, more precise manufacturing technique should be improved to get a more smoother surface finish.

How to cite this article

Varma DPK, Chidambaram S, Reddy KB, Vijay M, Ravindranath D, Prasad MR. Comparison of Galvanic Corrosion Potential of Metal Injection Molded Brackets to that of Conventional Metal Brackets with Nickel-Titanium and Copper Nickel-Titanium Archwire Combinations. J Contemp Dent Pract 2013;14(3):488-495.
A Survey of Complete Denture Patients Experiencing Difficulties with their Prostheses
Authors: Sanyal Pronob , Ghanchi Mohsin , Gosavi Sandesh S , Malik Shambhvi Anil
Published: September 2013

Objective

The objective of this study was to investigate the problems faced by patients having complete dentures and the cleanliness of dentures by the patients.

Materials and methods

This cross-sectional study is done with a sample of 178 patients having complete prosthesis since 1 year. A self-administered structured questionnaire pretested through a pilot survey was used in the study. The data were analyzed using the SPSS version 16.0. The Student's t-test, ANOVA and post hoc test were used as test of significance.

Results

Mastication discomfort and looseness of denture were the most common complaints followed by lack of retention 35.4%), bad breath (29.8%), tongue restriction (26.4%) and food accumulation (24.7%). There was a significant relationship of complaints with age groups (p = 0.00).

Clinical significance

This study concluded that most of the patients were present with complaints due to dentures. So, dental professionals should pay serious attention to their patients for subjective acceptable result of the dentures and also advice them to properly maintain hygiene of dentures.

How to cite this article

Gosavi SS, Ghanchi M, Malik SA, Sanyal P. A Survey of Complete Denture Patients Experiencing Difficulties with their Prostheses. J Contemp Dent Pract 2013;14(3):524-527.
Comparative Analysis of Rationale used by Dentists and Patient for Final Esthetic Outcome of Dental Treatment
Authors: Gujjarlapudi Manmohan Choudary , Reddy S Varalakshmi , Madineni Praveen Kumar , Sudheer A , Sreedevi B , Reddy Patelu Sunil Kumar
Published: September 2013

Aim

To compare and evaluate the perceptions of esthetics among dentists and patients regarding the final esthetic outcome of a dental treatment.

Background

Esthetics is a matter of perception and is associated with the way different people look at an object. What constitutes esthetic for a particular person may not be acceptable for another. Hence it is subjective in nature. This becomes more obvious during the post-treatment evaluation of esthetics by dentist and the concerned patient. Opinion seldom matches. Hence, the study is a necessary part of the process of understanding the mind of dentist and patient regarding what constitutes esthetics.

Technique

A survey has been conducted by means of a questionnaire consisting of 10 questions, on two groups of people. First group consists of 100 dentists picked at random in Kanyakumari district of Tamil Nadu, India. Second group consisted of 100 patients who required complete denture prosthesis. The second group was divided into two subgroups A and B. Subgroup A consisting of 50 men and subgroup B consisting of 50 women. In each subgroup 25 patients were selected in age group of 40 to 50 and 25 patients were selected in the age group of 50 to 60. The questionnaire was given to both the groups and asked to fill up, which was then statistically analyzed to look for patterns of thought process among them.

Results

Results were subjected to statistical analysis by Student's t-test.

Conclusion

Perceptions of esthetics differs from dentist who is educated regarding esthetic principles of treatment and a patient who is not subjected to such education. Since, the questions were formulated such that patients could better understand the underlying problem, the final outcome of survey is a proof that dentists need to take into account what the patient regards as esthetics in order to provide a satisfactory treatment.

Clinical and academic significance

The current study helps the dentist to better educate the patient regarding esthetics so that patient appreciates the final scientifically based esthetic outcome of treatment. It also helps the dental students to understand the underlying patient's thought process regarding esthetics.

How to cite this article

Reddy SV, Madineni PK, Sudheer A, Gujjarlapudi MC, Sreedevi B, Reddy PSK. Comparative Analysis of Rationale used by Dentists and Patient for Final Esthetic Outcome of Dental Treatment. J Contemp Dent Pract 2013;14(3):532-535.
Assessment of Palatal Masticatory Mucosa: A Cross-sectional Study
Authors: Anuradha BR , Gopinadh Anne , Shankar Bugude Shiva , John Bijoy , Prasad KA Ravi Varma , Devi K Naga Neelima
Published: September 2013

Aim

To treat mucogingival problems palatal masticatory mucosa is used as a donor material. This study aimed to determine the thickness of donor palatal mucosa and associations of age and gender in Indian subjects aged 14 to 60 years by direct clinical technique.

Materials and methods

Forty systemically and periodontally healthy Indian subjects (20 males; 20 females; age range of 14 to 60 years) enrolled in this study. Under local anesthesia bone sounding technique was performed at 15 defined and predetermined points. The Wilcoxon test was used to determine the difference in mucosal thickness between the age groups and between genders. Significance of the difference between individuals of different body mass index (BMI) was assessed by independent t-test.

Results

With mean thickness of 2.0 to 3.7 mm, the younger age group demonstrated significantly thinner donor mucosa (mean 2.8 ± 0.3 mm) than the older age group (mean 3.1 ± 0.3 mm). Within the same age group though statistically not significant; males had thicker mucosa than females. From the canine to second premolar areas and in the sites furthest from the gingival margin mucosa thickness increased. When correlated with subject's BMI, in all probed sites males demonstrated significantly a thicker mucosa than females. Within each group subjects with high BMI demonstrated thicker donor mucosa.

Conclusion

Current study showed that in both adult and young individuals, premolar and canine areas can be the right site for harvesting donor tissue. Even in young subjects subepithelial connective tissue (CT) graft can be harvested in adequate volume. Donor tissue thickness can be influenced by factors like genetics and race, which need to be further evaluated.

Clinical significance

Premolar and canine areas serve as appropriate choice to harvest palatal masticatory mucosa. Even in young patients the volume of donor tissue available is sufficient enough to consider the subepithelial CT graft procedure. Donor tissue thickness can be influenced by factors like genetics and race, which need to be further evaluated.

How to cite this article

Anuradha BR, Shankar BS, John B, Prasad KARV, Gopinadh A, Devi KNN. Assessment of Palatal Masticatory Mucosa: A Cross-sectional Study. J Contemp Dent Pract 2013;14(3):536-543.
Secondary organic aerosol formation from gasoline vehicle emissions in a new mobile environmental reaction chamber
Authors: Platt S. M. , El Haddad I. , Zardini A. A. , Clairotte M. , Astorga C. , Wolf R. , Slowik J. G. , Temime-Roussel B. , Marchand N. , Ježek I. , Drinovec L. , Močnik G. , Möhler O. , Richter R. , Barmet P. , Bianchi F. , Baltensperger U. , Prévôt A. S. H.
Published: September 2013

Abstract. We present a new mobile environmental reaction chamber for the simulation of the atmospheric aging of different emission sources without limitation from the instruments or facilities available at any single site. Photochemistry is simulated using a set of 40 UV lights (total power 4 KW). Characterisation of the emission spectrum of these lights shows that atmospheric aging of emissions may be simulated over a range of temperatures (−7 to 25 °C). A photolysis rate of NO2, JNO2, of (8.0 ± 0.7) × 10−3 s−1 was determined at 25 °C. We demonstrate the utility of this new system by presenting results on the aging (OH = 12 × 106 cm−3 h) of emissions from a modern (Euro 5) gasoline car operated during a driving cycle (New European Driving Cycle, NEDC) on a chassis dynamometer in a vehicle test cell. Emissions from the entire NEDC were sampled and aged in the chamber. Total organic aerosol (OA; primary organic aerosol (POA) emission + secondary organic aerosol (SOA) formation) was (369.8–397.5)10−3 g kg−1 fuel, or (13.2–15.4) × 10−3 g km−1, after aging, with aged OA/POA in the range 9–15. A thorough investigation of the composition of the gas phase emissions suggests that the observed SOA is from previously unconsidered precursors and processes. This large enhancement in particulate matter mass from gasoline vehicle aerosol emissions due to SOA formation, if it occurs across a wider range of gasoline vehicles, would have significant implications for our understanding of the contribution of on-road gasoline vehicles to ambient aerosols.
Modeling of very low frequency (VLF) radio wave signal profile due to solar flares using the GEANT4 Monte Carlo simulation coupled with ionospheric chemistry
Authors: Palit S. , Basak T. , Mondal S. K. , Pal S. , Chakrabarti S. K.
Published: September 2013

Abstract. X-ray photons emitted during solar flares cause ionization in the lower ionosphere (~60 to 100 km) in excess of what is expected to occur due to a quiet sun. Very low frequency (VLF) radio wave signals reflected from the D-region of the ionosphere are affected by this excess ionization. In this paper, we reproduce the deviation in VLF signal strength during solar flares by numerical modeling. We use GEANT4 Monte Carlo simulation code to compute the rate of ionization due to a M-class flare and a X-class flare. The output of the simulation is then used in a simplified ionospheric chemistry model to calculate the time variation of electron density at different altitudes in the D-region of the ionosphere. The resulting electron density variation profile is then self-consistently used in the LWPC code to obtain the time variation of the change in VLF signal. We did the modeling of the VLF signal along the NWC (Australia) to IERC/ICSP (India) propagation path and compared the results with observations. The agreement is found to be very satisfactory.
A global model study of the impact of land-use change in Borneo on atmospheric composition
Authors: Warwick N. J. , Archibald A. T. , Ashworth K. , Dorsey J. , Edwards P. M. , Heard D. E. , Langford B. , Lee J. , Misztal P. K. , Whalley L. K. , Pyle J. A.
Published: September 2013

Abstract. In this study, a high resolution version of the Cambridge p-TOMCAT chemical transport model is used, along with measurement data from the 2008 NERC-funded Oxidant and Particle Photochemical Processes (OP3) project, to examine the potential impact of the expansion of oil palm in Borneo on atmospheric composition. Several model emission scenarios are run for the OP3 measurement period, incorporating emissions from both global datasets and local flux measurements. Using the OP3 observed isoprene fluxes and OH recycling chemistry in p-TOMCAT substantially improves the comparison between modelled and observed isoprene and OH concentrations relative to using MEGAN isoprene emissions without OH recycling. However, a similar improvement was also achieved without using HOx recycling, by fixing boundary layer isoprene concentrations over Borneo to follow the OP3 observations. An extreme hypothetical future scenario, in which all of Borneo is converted to oil palm plantation, assessed the sensitivity of the model to changes in isoprene and NOx emissions associated with land-use change. This scenario suggested a 70% upper limit on surface ozone increases resulting from land-use change on Borneo, excluding the impact of future changes in emissions elsewhere. Although the largest changes in this scenario occurred directly over Borneo, the model also calculated notable regional changes of O3, OH and other species downwind of Borneo and in the free troposphere.
Absorption properties of Mediterranean aerosols obtained from multi-year ground-based remote sensing observations
Authors: Mallet M. , Dubovik O. , Nabat P. , Dulac F. , Kahn R. , Sciare J. , Paronis D. , Léon J. F.
Published: September 2013

Abstract. Aerosol absorption properties are of high importance to assess aerosol impact on regional climate. This study presents an analysis of aerosol absorption products obtained over the Mediterranean basin or land stations in the region from multi-year ground-based AERONET observations with a focus on the Absorbing Aerosol Optical Depth (AAOD), Single Scattering Albedo (SSA) and their spectral dependence. The AAOD and Absorption Angström Exponent (AAE) dataset is composed of daily averaged AERONET level 2 data from a total of 22 Mediterranean stations having long time series, mainly under the influence of urban-industrial aerosols and/or soil dust. This dataset covers the 17-yr period 1996–2012 with most data being from 2003–2011 (~89% of level-2 AAOD data). Since AERONET level-2 absorption products require a high aerosol load (AOD at 440 nm > 0.4), which is most often related to the presence of desert dust, we also consider level-1.5 SSA data, despite their higher uncertainty, and filter out data with an Angström exponent < 1.0 in order to study absorption by carbonaceous aerosols. The SSA dataset includes AERONET level-2 products. Sun-photometer observations show that values of AAOD at 440 nm vary between 0.024 ± 0.01 (resp. 0.040 ± 0.01) and 0.050 ± 0.01 (0.055 ± 0.01) for urban (dusty) sites. Analysis shows that the Mediterranean urban-industrial aerosols appear "moderately" absorbing with values of SSA close to ~0.94–0.95 ± 0.04 (at 440 nm) in most cases except over the large cities of Rome and Athens, where aerosol appears more absorbing (SSA ~0.89–0.90 ± 0.04). The aerosol Absorption Angström Exponent (AAE, estimated using 440 and 870 nm) is found to be larger than 1 for most sites over the Mediterranean, a manifestation of mineral dust (iron) and/or brown carbon producing the observed absorption. AERONET level-2 sun-photometer data indicate a possible East-West gradient, with higher values over the eastern basin (AAEEast = 1.39/AAEWest = 1.33). The North-South AAE gradient is more pronounced, especially over the western basin. Our additional analysis of AERONET level-1.5 data also shows that organic absorbing aerosols significantly affect some Mediterranean sites. These results indicate that current climate models treating organics as nonabsorbing over the Mediterranean certainly underestimate the warming effect due to carbonaceous aerosols.