bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of the Restoration Success of Endodontic Therapy of the Primary Molars
Authors: Kirzioglu Zuhal , Gungor Ozge Erken , Ciftci Z Zahit
Published: September 2019

Objectives: The aim of this study was to evaluate the clinical and radiographic success rates of pulpotomized primary molar teeth restored with a compomer material with using United States Public Health Service (USPHS) criteria. Methods: In 173 primary molars of 156 child patients, aged within 4-9 years (mean age: 6.1±1.4 years), conventional pulpotomy treatment were performed. The teeth treated using calcium hydroxide, formocresol or ferric sulphate. After pulpotomy procedure, teeth were restored with compomer material. The teeth were evaluated as clinically and radiographically during a period of 12-24 months. Both of success of pulpotomy treatment and also restorative material (compomer material) were evaluated during follow-up period. The data were assessed with chi-square test. Results: At the end of the first year, 45% of initial treated teeth were checked, but only 18% were checked at the end of the second year. The first year success rates in the groups treated with CH, FC, and FS were 87.5%, 95%, and 79%, respectively, and, as the number of controllable patients was lower, the success rates on available teeth were determined to be 88.3% and 80%, respectively, according to the materials at the end of the second year. Restorations having been made, they were analyzed in accordance with USPHS criteria. Conclusions: At the end of the first year, 67.5% of compomer restorations were detected to be original and healthy and at the end of the second year, 57% were deemed healthy. No statistically significant relationships were found between marginal adaptation, secondary caries and pulpotomy success (chi-square test, P>.05). Among the three groups, there is no significant difference in terms of success. The least successful age group was defined as 4-6 years. (Eur J Dent 2011;5:415-422)
Evaluation of the Immediate Dentofacial Changes in Late Adolescent Patients Treated with the ForsusTM FRD
Authors: Gunay Esen Ali , Arun Tulin , Nalbantgil Didem
Published: September 2019

Objectives: The purpose of this study was to evaluate the short-term dentoalveolar and soft tissue changes in late adolescent patients treated with the ForsusTM FRD. Methods: A prospective study was carried out on 54 lateral cephalometric radiograms that were taken before placement and after removal of the appliance in the treatment group (15 subjects) and at the beginning and six months after in the control group (12 subjects). The patient selection criteria were as follows: skeletal and dental Class II malocclusion due to retrognatic mandible, normal or low-angle growth pattern, post-peak growth period, no extracted or congenitally missing permanent teeth, and minimum crowding in the lower dental arch. Results: The statistical assesment of the data suggested the following results: No sagital and vertical skeletal changes were induced. The mandibular incisors were protruded and intruded, while the maxillary incisors were retruded and extruded. The occlusal plane was rotated in clockwise direction as a result of these dentoalveolar changes. Overbite and overjet were reduced in all patients. Soft tissue profile slightly improved. Conclusions: The results revealed that, in late-adolescent patients ForsusTM FRD corrected Class II discrepancies through maxillary and mandibular dentoalveolar changes. (Eur J Dent 2011;5:423-432)
Apert syndrome: A case report
Authors: Ileri Zehra , Goyenc Yasar Bedii
Published: September 2019

The purpose of this report is to present Apert syndrome patient by highlighting craniofacial characteristics and orthodontic approach to treatment

The patient, a 16-day-old female and the second child of healthy parents, was admitted to our department with primary complaint of cleft palate. She had a cone-shaped calvarium, midface hypoplasia, syndactyly of the hands and feet, hypertelorism, proptosis and cleft palate. After taking maxillary impression, an acrylic appliance was applied to orientate the growing and enable the feeding

A case with Apert syndrome undergoes the orthodontic treatment for a long time and also a multidisciplinary approach is essential to determine the best collaborative corrective plan for the deficiencies of the patient. (Eur J Dent 2012;6:110-113)
A diffuse interface model for two-phase flows with phase transition
Authors: Pan Lun Sheng , Lou Jing , Li Hong Ying , Kang Chang Wei
Published: September 2019

A thermodynamically consistent diffuse interface model is developed for two-phase flows with phase transition. Inside the liquid-vapor mixing layer, the Cahn-Hilliard equation governing the evolution of liquid/vapor species explicitly includes the phase transition between the two species. In the present model, the specific Helmholtz free energy of the binary mixing fluid as well as other thermodynamic functions consists of a classical part (ideal mixing free energy plus a double-well potential of the mass fraction) and a nonclassical part consisting of the gradient of mass fraction. The nonclassical chemical potential is defined in a manner similar to the classical chemical potential. According to the present model, there exists a (conserved) nonclassical stress tensor in the mixing fluid, which is a distributed form of the surface tension across the mixing layer. Using the principle of entropy increase, it is observed that the rate of local phase transition is proportional to the local generalized chemical potential, and a system of transport equations of the mixing fluid is derived. This system of equations can be reduced to that of Guo and Lin [“A thermodynamically consistent phase-field model for two-phase flows with thermocapillary effects,” J. Fluid Mech. 766, 226 (2015)] except for the formula on chemical potential. The present diffuse-interface model will also be reduced to the general classical sharp interface model when the mixing layer collapses to a sharp surface.
Metal ion binding by humic substances as emergent functions of labile supramolecular assemblies
Authors: Vialykh Elena A. , Salahub Dennis R. , Achari Gopal
Published: September 2019

Environmental contextThe fundamental basis for the high flexibility of humic substances is still unclear, though it is crucial for the understanding of metal bioavailability and toxicity in soil and aqueous environments. We show at the molecular level how characteristics of organic matter affect metal binding depending on the environmental conditions. Such understanding will help in the modulation of metal availability in soil and water in changing environmental situations.
AbstractIn this work, we explore the hypothesis that humic substances (HS) can be perceived as labile supramolecular assemblages, the functioning of which is mainly determined by chemical composition and characteristics, the size of molecular units and weak intermolecular forces, rather than the exact primary structure of molecular moieties and their spatial configuration. To test the hypothesis, 72 computational models of three different organic mixtures were composed. The formation of inner and outer sphere metal–ligand complexes, metal binding sites, complex configurations, binding energies and aggregation/dissolution as emergent properties of HS were determined under various conditions. The results of computational modelling revealed that: (i) the highest Cu2+ binding (55.6%) was by the SRFA-22 organic model, which represents low-molecular-weight fulvic acids. In contrast, the highest amount of inner-sphere Mg–organic matter complex (63.4%) was formed in SRHA-6, which has higher-molecular-weight constituents. Therefore, a correlation between the type of cation, the system aromaticity and the extent of metal complexation is proposed. (ii) Increase of metal ion concentration and decrease of water content resulted in an increase in the number of hydrogen bonds and more compact and stable aggregates with lower hydrophilic and higher hydrophobic surface areas in SRFA-22. However, in SRHA-6, the results varied owing to the competition between metal binding, H-bonding and non-polar interactions in the structural arrangement of the aggregates. In general, the aggregation process, driven by metal complexation and water removal, resulted in the formation of more stable conformers, with lower potential energy, with the only exception of SRHA-6–Cu.
Extrafloral nectaries in Leguminosae: phylogenetic distribution, morphological diversity and evolution
Authors: Marazzi Brigitte , Gonzalez Ana Maria , Delgado-Salinas Alfonso , Luckow Melissa A. , Ringelberg Jens J. , Hughes Colin E.
Published: September 2019

Extrafloral nectaries (EFNs) mediating ecologically important ant–plant protection mutualisms are especially common and unusually diverse in the Leguminosae. We present the first comprehensively curated list of legume genera with EFNs, detailing and illustrating their systematic and phylogenetic distributions, locations on the plant, morphology and anatomy, on the basis of a unified classification of EFN categories and a time-calibrated phylogeny, incorporating 710 of the 768 genera. This new synthesis, the first since Mckey (1989)’s seminal paper, increases the number of genera with EFNs to 153 (20% of legumes), distributed across subfamilies Cercidoideae (1), Detarioideae (19), Caesalpinioideae (87) and Papilionoideae (46). EFNs occur at nine locations, and are most prevalent on vegetative plant parts, especially leaves (74%) and inflorescence axes (26%). Four main categories (with eight subcategories) are recognised and include the following: formless, trichomatic (exposed, hollow), parenchymatic (embedded, pit, flat, elevated) and abscission zone EFNs (non-differentiated, swollen scars). Phylogenetic reconstruction of EFNs suggests independent evolutionary trajectories of different EFN types, with elevated EFNs restricted almost exclusively to Caesalpinioideae (where they underwent spectacular morphological disparification), flat EFNs in Detarioideae, swollen scar EFNs in Papilionoideae, and Cercidoideae is the only subfamily bearing intrastipular EFNs. We discuss the complex evolutionary history of EFNs and highlight future research directions.
Quantisation and nilpotent limits of Mishchenko–Fomenko subalgebras
Authors: Molev Alexander , Yakimova Oksana
Published: September 2019

For any simple Lie algebrag\mathfrak {g}and an elementμ∈g∗\mu \in \mathfrak {g}^*, the corresponding commutative subalgebraAμ\mathcal {A}_{\mu }ofU(g)\mathcal {U}(\mathfrak {g})is defined as a homomorphic image of the Feigin–Frenkel centre associated withg\mathfrak {g}. It is known that whenμ\muis regular this subalgebra solves Vinberg’s quantisation problem, as the graded image ofAμ\mathcal {A}_{\mu }coincides with the Mishchenko–Fomenko subalgebraA¯μ\overline {\mathcal {A}}_{\mu }ofS(g)\mathcal {S}(\mathfrak {g}). By a conjecture of Feigin, Frenkel, and Toledano Laredo, this property extends to an arbitrary elementμ\mu. We give sufficient conditions onμ\muwhich imply the property. In particular, this proves the conjecture in typeCand gives a new proof in typeA. We show that the algebraAμ\mathcal {A}_{\mu }is free in both cases and produce its generators in an explicit form. Moreover, we prove that in all classical types generators ofAμ\mathcal {A}_{\mu }can be obtained via the canonical symmetrisation map from certain generators ofA¯μ\overline {\mathcal {A}}_{\mu }. The symmetrisation map is also used to produce free generators of nilpotent limits of the algebrasAμ\mathcal {A}_{\mu }and to give a positive solution of Vinberg’s problem for these limit subalgebras.
Propriétés de maximalité concernant une représentation définie par Lusztig
Authors: Waldspurger J.-L.
Published: September 2019

Let

λ
\lambda

be a symplectic partition, denote

J
o
r

d

b
p

(
λ
)

Jord^{bp}(\lambda )

the set of even positive integers which appear in

λ
\lambda

, and let a map

ϵ
:
J
o
r

d

b
p

(
λ
)
→
{
±
1
}

\epsilon :Jord^{bp}(\lambda ) \to \{\pm 1\}

. The generalized Springer’s correspondence associates to

(
λ
,
ϵ
)

(\lambda ,\epsilon )

an irreducible representation

ρ
(
λ
,
ϵ
)

\rho (\lambda ,\epsilon )

of some Weyl group. We can also define a representation

ρ
_

(
λ
,
ϵ
)

\underline {\rho }(\lambda ,\epsilon )

of the same Weyl group, in general reducible. Roughly speaking,

ρ
(
λ
,
ϵ
)

\rho (\lambda ,\epsilon )

is the representation of the Weyl group in the top cohomology group of some variety and

ρ
_

(
λ
,
ϵ
)

\underline {\rho }(\lambda ,\epsilon )

is the representation in the sum of all the cohomology groups of the same variety. The representation

ρ
_

\underline {\rho }

decomposes as a direct sum of

ρ
(

λ
′

,

ϵ
′

)

\rho (\lambda ’,\epsilon ’)

with some multiplicities, where

(

λ
′

,

ϵ
′

)

(\lambda ’,\epsilon ’)

describes the set of pairs similar to

(
λ
,
ϵ
)

(\lambda ,\epsilon )

. It is well know that

(
λ
,
ϵ
)

(\lambda ,\epsilon )

appears in this decomposition with multiplicity one and is minimal in this decomposition. That is, if

(

λ
′

,

ϵ
′

)

(\lambda ’,\epsilon ’)

appears, we have

λ
′

>
λ

\lambda ’>\lambda

or

(

λ
′

,

ϵ
′

)
=
(
λ
,
ϵ
)

(\lambda ’,\epsilon ’)=(\lambda ,\epsilon )

. Assuming that

λ
\lambda

has only even parts, we prove that there exists also a maximal pair

(

λ

m
a
x

,

ϵ

m
a
x

)

(\lambda ^{max},\epsilon ^{max})

. That is,

(

λ

m
a
x

,

ϵ

m
a
x

)

(\lambda ^{max},\epsilon ^{max})

appears with positive multiplicity (in fact one) and, if

(

λ
′

,

ϵ
′

)

(\lambda ’,\epsilon ’)

appears, we have

λ

m
a
x

>

λ
′

\lambda ^{max}>\lambda ’

or

(

λ
′

,

ϵ
′

)
=
(

λ

m
a
x

,

ϵ

m
a
x

)

(\lambda ’,\epsilon ’)=(\lambda ^{max},\epsilon ^{max})

.
Getting a PhD in a STEM field is a great start to a winning career
Authors: Maxon Mary Elizabeth
Published: September 2019

A PhD in a scientific or engineering discipline can lead to a multitude of interesting positions, spanning from research in academia and industry to grant-making for a philanthropic organization to science policy positions in state and federal governments. I know because my career path has given me opportunities in all of them, and in each position my skill set grew in new and unexpected, positive ways.
Higher Education Policy in the European Union
Authors: Dakowska Dorota
Published: September 2019

Whether higher education (HE) can be defined as a European Union (EU) policy has been matter of debate. Formally, education is still a domestic prerogative, and in principle, the EU can only support and supplement national governments’ initiatives in the sector. Yet, this official division of tasks has been challenged in many ways over the last decades. First, the history of European integration shows that the European community took an early interest in educational matters. The Treaty of Rome established a community competency on vocational training. Subsequently, the European Commission framed HE and vocational training as two entangled policies. Second, the EU institutions, the member states, and noninstitutional actors have coordinated in innovative ways, through soft governance processes promoted by the Bologna Process and the EU Lisbon—and later Europe 2020—strategy, to impose a European HE governance based on standards and comparison. Third, the study of HE requires going beyond an EU-centric perspective, with international organizations such as the OECD and the Council of Europe cooperating closely with the European Commission. HE has been increasingly shaped by global trends, such as the increased competition between universities. The mechanisms of European HE policy change have elicited academic debates. Three main explanations have been put forward: the power of instruments and standards, the impact of the Commission’s funding schemes, and the influence of interconnected experts, stakeholders and networks. Domestic translations of European recommendations are highly diverse and reveal a gap between formal adaptations and local practices. Twenty years after the Bologna declaration, the European Higher Education Area (EHEA) presents a mixed picture. On the one hand, increased mobility and the growing interconnectedness of academic schemes facilitate the launch of ambitious projects such as the “European universities.” On the other hand, concerns are periodically raised about the growing bureaucratization of the process and the widening gap between the small world of the Brussels stakeholders and everyday academic practices in EHEA participant countries. Paradoxically, smaller and non-EU countries have been more actively involved in advancing the EHEA than large, older EU member states.
Brazil-US Relations
Authors: Cameron James
Published: September 2019

Although never enemies, the United States and Brazil have a complex history stemming primarily from the significant imbalance in power between the Western Hemisphere’s two largest nations. The bedrock of the relationship, trade, was established in the 19th century due to the rapid growth in US demand for Brazilian coffee, and since then commercial disputes have been a constant feature of the relationship. Brazil’s periodic attempts to use cooperation with Washington to enhance its own economic and diplomatic status during the 20th century generally fell short of expectations due to the relative lack of weight the United States gave to Brazilian objectives. Consequently, Brazilian foreign policy has swung between advocating closer ties with the United States and asserting the country’s autonomy from the colossus to the north. American support for the 1964 military coup left a persistent legacy of suspicion. In the early 21st century, the two countries enjoy relatively good relations.

Brazil and the United States also have a rich history of transnational interactions, encompassing areas such as culture, race, business, trade unionism, and human rights. Both countries’ processes of racial and national identity formation have been influenced by the other. US business figures have at different times attempted to shape Brazil’s economic development along their preferred lines, while US culture has been used to further Washington’s political objectives. During the dictatorship, transnational actors worked together to push back against the regime and US national security policy. This history of transnational relations has become an increasingly important part of the scholarship on the United States and Brazil.
Cellular Optimization of Nanofat: Comparison of Two Nanofat Processing Devices in Terms of Cell Count and Viability
Authors: Cohen Steven R , Tiryaki Tunç , Womack Hayley A , Canikyan Serli , Schlaudraff Kai Uwe , Scheflan Michael
Published: September 2019

Background

Nanofat was introduced by Tonnard and Verpaele in 2013. Their initial observations in intradermal applications showed improvement in the appearance of the skin. Since then, a number of Nanofat devices have been introduced. The cellular content in the processing of Nanofat is not the same in every device, yet the cellular composition is responsible for the biologic action of Nanofat. The authors sought to find a different means to produce a matrix rich Nanofat to optimize the cellular content.

Objectives

The primary objective of this study was to compare cell counts, cultures, and cell viabilities produced by LipocubeNano (Lipocube, Inc., London, UK) in comparison to Tulip’s NanoTransfer (Tulip Medical, San Diego, CA) processing methods.

Methods

Twenty milliliters of fat were harvested from 10 patients in order to test two methods of Nanofat production. Ten milliliters of fat were used to assess each method and, after the final product was obtained, enzymatic digestion for stromal vascular fraction (SVF) isolation was performed. A Muse Flow-cytometer was used to measure cell counts and cell viabilities, cell cultures were performed, and cell images were taken with a florescent microscope.

Results

The LipocubeNano was shown to be superior to Tulip’s NanoTransfer system of progressive downsizing with final filtering, which appeared to trap more fibrous tissue leading to lower amounts of SVF. LipocubeNano resulted in higher cell counts (2.24 × 106/cc), whereas Tulip’s NanoTransfer method resulted in a lower cell count at 1.44 × 106/cc. Cell viability was the same (96.05%) in both groups.

Conclusions

Nanofat from LipocubeNano has a higher regenerative cell count and more SVF cells than the other common mechanical method of Nanofat processing. This new means of mechanical processing preserves more matrix, optimizing the cellular content of the Nanofat, thus having potentially a higher regenerative effect.

Level of Evidence: 5
Nest Microclimate, Water-Vapor Conductance, and Water Loss in Heron and Tern Eggs
Authors: Vleck Carol Masters , Vleck David , Rahn Hermann , Paganelli Charles V.
Published: September 2019

Rates of water loss (ṀH2O) were measured in eggs of seven species of tree-nesting Ciconiiformes and three species of ground-nesting Charadriiformes during natural incubation. Measurements of egg temperature, conductance of the egg shell to water vapor, and nest and ambient humidity allow one to calculate the difference in water-vapor pressure (ΔP) between egg and nest and between nest and ambient air. ΔP between egg and nest was significantly lower in ground-nesting species (23 torr) than in tree-nesting species (31 torr). We suggest that low ΔP in ground-nesting species was due to relatively high humidity (ca. 27 torr) in nests built on the ground compared to the humidity in loose stick nests of tree-nesting species (ca. 14 torr). Water-vapor conductance of eggs from more humid nests is relatively higher than that of eggs from less humid nests (107% and 78% of predicted values, respectively), resulting in similar fractional losses in mass for the whole incubation period in both groups of birds. (ṀH2O) was not always constant throughout incubation. We suggest that changes in (ṀH2O) may be due to changes in ambient humidity and/or egg temperature.
Mollusk Predation by Snail Kites in Colombia
Authors: Snyder Noel F. R. , Kale Herbert W.
Published: September 2019

Snail Kites (Rostrhamus sociabilis sociabilis) observed along the lower Río Magdalena in northern Colombia fed heavily on Pomacea chemnitzi but also took Marisa cornuarietis, a smaller species. The kites captured Pomacea preferentially over Marisa and had difficulties extracting Marisa from its shell. They also failed to extract some large specimens of P. chemnitzi. Failures with both species were apparently related to problems in removing opercula. These observations indicate that R. sociabilis can no longer be considered a strict specialist on Pomacea.
Systematics of the Southern Forms of Selasphorus (Trochilidae)
Authors: Stiles F. Gary
Published: September 2019

Based upon evidence from morphology, behavior, and ecology, I propose that the taxonomy of the southern Selasphorus hummingbirds be set forth as follows:

Selasphorus flammula Salvin: Volcano Hummingbird

S. f. flammula Salvin, 1864 (Volcán Irazú, Volcán Turrialba, Costa Rica)

S. f. torridus Salvin, 1870 (Cordillera de Talamanca, Costa Rica-Panama)

S. f. simoni Carriker, 1910 (Volcán Poás, Volcán Barba, Costa Rica)

Selasphorus scintilla Gould, 1850: Scintillant Hummingbird (Cordillera de Tilarán, Costa Rica south and east to Volcán Chiriquí, Panama, at lower elevations than populations of the preceding species).

Selasphorus ardens Salvin, 1870: Glow-throated Hummingbird (Serranía de Tabasará, Panama).

S. scintilla and S. ardens may comprise a superspecies. S. "underwoodii" is a hybrid between S. scintilla and S. f. flammula.

The breeding distributions of flammula, simoni, and torridus are entirely allopatric, but the birds may occur together in the nonbreeding season. In particular, a pronounced postbreeding movement may carry many torridus into the breeding areas of flammula and even simoni. A possible evolutionary history of these forms is proposed in relation to post-Pleistocene climatic changes, ecological requirements, and probable populations sizes.
Size and Locomotion in Teratorns (Aves: Teratornithidae)
Authors: Campbell Kenneth E. , Tonni Eduardo P.
Published: September 2019

The extinct family Teratornithidae contains the world's largest known flying birds. A new method of determining body weights of extinct birds, based on the size of their tibiotarsi, facilitates the estimation of the wing dimensions of these giant birds. An analysis of the bones of the teratorn wing shows that they closely resemble those of condors, suggesting that teratorns flew in a manner similar to these large New World vultures. The bones of the pelvic girdle and hindlimbs indicate that teratorns were probably agile on the ground, though better adapted for walking and stalking than running. We estimate that the largest teratorn, Argentavis magnificens, weighed 80 kg and had a wingspan of 6-8 m. It probably became airborne by spreading its huge wings into the strong, continuous, westerly winds that blew across southern South America before the elevation of the Andes Mountains and, once aloft, flew in the manner of condors.
Specific Status and Behavior of Cymbilaimus sanctaemariae, the Bamboo Antshrike, from Southwestern Amazonia
Authors: Pierpont Nina , Fitzpatrick John W.
Published: September 2019

Cymbilaimus sanctaemariae (Formicariidae), previously regarded as a poorly known subspecies of C. lineatus, is a distinct species. The two forms overlap broadly in geographical range and are distinct in morphology, plumage, voice, and habitat. We propose the vernacular name Bamboo Antshrike. The species apparently links Cymbilaimus and Thamnophilus. It is a member of the growing list of bamboo-associated birds endemic to southwestern Amazonia.
Spatial Patterns of Yearling Male Blue Grouse and Their Relation to Recruitment into the Breeding Population
Authors: Jamieson Ian G. , Zwickel Fred C.
Published: September 2019

Movements of yearling male Blue Grouse (Dendragapus obscurus) were monitored by radio telemetry during the springs of 1980 and 1981, on Hardwicke Island, British Columbia. The locations of the birds were clumped around territories of adult males. Most birds were associated with a few occupied territories, others settled near vacant sites that had been used as territories in previous years, and a few moved widely over the breeding range. Some territories attracted more yearlings than others. Presumed costs and benefits that may be associated with different types of spatial patterns of yearling males are discussed.
Effects of Experience and Body Weight on Incubation Behavior of Canada Geese
Authors: Aldrich Thomas W. , Raveling Dennis G.
Published: September 2019

During 1979 and 1980, we studied the incubation behavior and body-weight dynamics of captive Canada Geese (Branta canadensis moffitti) with known breeding histories. Females were attentive to their nests for 97.5% of the incubation period and lost 27% of their initial body weight. Heavier females were more attentive to their nests and lost more weight during incubation than did lighter females. Variation in body weight among females was greatest at the onset of incubation and least at hatch, which suggests that females invested maximum reserves in incubation. Recess frequency and duration increased throughout incubation, resulting in more foraging time for the female. Once a lower critical weight of about 3,200 g was reached, the amount of recess time taken increased dramatically, probably because lipid reserves were depleted. Females nesting for the first time began incubation at a lighter body weight and were less attentive than experienced females. All inexperienced females were either 4 or 5 yr old, but their egg production (4 eggs) was that of 2- or 3-yr-old wild females. This indicated that experience rather than age was the important variable affecting acquisition of reserves. Inattentiveness to a nest by a female prolongs the duration of incubation and exposes the nest to a greater risk of predation. The inability of inexperienced females to gain enough reserves to provide for both maximum clutch size and attentiveness during incubation may be a major explanation for the lower hatching success of geese nesting for the first time.
The White-Crowned Sparrow: Reproductive Success (1975-1980)
Authors: Petrinovich Lewis , Patterson Thomas L.
Published: September 2019

We report the results of a 6-yr study of two banded populations of sedentary White-crowned Sparrows (Zonotrichia leucophrys nuttalli). All birds were banded and territory holders identified each year. We determined the outcome of 1,264 nests and located all nests of 186 pairs during a breeding season. Each pair produced an average of 2.5 fledglings in a season. Given the fact that a territorial bird has an expectancy of remaining on territory about 1.5 yr, the population seems to be at a stable level. The birds at one of the study locations, Twin Peaks, were less successful overall and more variable year to year than at the other, the Presidio. The differences between the two areas could be the result of severe weather changes that altered the characteristics of the vegetation.

Only 0.34 of the total number of nests (978) were successful, predation being the greatest cause of nest failure. Of the total nests, 0.39 were lost to predation (0.13 to egg predation and 0.26 to nestling predation). Survival rates indicate that nest mortality is 0.0197 per day for the incubation stage, 0.0450 per day for the nestling stage, and 0.0366 per day for the total nesting period. Although it is possible that observer disturbance biased the results, the increased understanding of these birds that is derived from establishing natal sites, parentage, and kinship is of greater benefit than the probable cost of any such disturbance.
Songs of the Alder Flycatcher (Empidonax alnorum) and Willow Flycatcher (Empidonax traillii) are Innate
Authors: Kroodsma Donald E.
Published: September 2019

I studied the song development of five Willow Flycatchers (Empidonax traillii) and four Alder Flycatchers (Empidonax alnorum) taken from nests at 7-10 days of age. Three Willow Flycatchers and four Alder Flycatchers were tutored with songs of the other species, and two Willow Flycatchers served as controls, hearing only conspecific songs. All nine subjects, both females (when administered exogenous testosterone) and males, and both experimentals and controls, produced remarkably normal songs; slight differences between songs of wild and experimental subjects could be attributed to motivational states rather than to the effects of acoustic isolation in the laboratory. I found no microgeographic variation of wild songs, no evidence of learning from a tutor tape, nor any similarity of song characters among kin. The vocal development of these suboscine flycatchers is strikingly different from that of typical oscines, where vocal learning is the rule.
Parental Expenditure of Time and Energy in the Abert's Towhee (Pipilo aberti)
Authors: Finch Deborah M.
Published: September 2019

Daily activity budgets of male and female Abert's Towhees (Pipilo aberti) were measured in 1980 during the reproductive cycle and then converted into energy budgets to determine the relative demands of different nesting phases. Mean daily energy expenditures (DEEtot) in males reached a seasonal maximum of 126.7 kJ, or 2.16 times basal metabolic rate (BMR), in the prenesting phase. Thermoregulatory demands accounted for higher energy expenses in this phase. The cost for females was also high in the prenesting phase but was exceeded by DEEtot in the egg-laying phase. Average DEEtot was at a seasonal minimum of 103.8 kJ, or 1.8 times BMR, in incubating females. Females conserved energy in the incubation phase by minimizing activity, and 78% of the variation of DEEtot in individual females was explained by mean daily air temperature. Activity costs DEEact differed significantly between males and females during the incubation phase, but DEEtot did not. Mean DEEact and DEEtot were significantly greater in females during the nestling period than during incubation. DEEact explained 58% of the individual variation in female DEEtot in the nestling phase, whereas air temperature explained only 28% of the variation. Interphasic variation in DEEact was wider in females than males, because females closely tracked offspring requirements by attending at the nest. Males did not incubate or brood, and spare time spent "loafing" tended to minimize DEEact. Excluding the egg-laying female, estimates of DEEtot in individual towhees ranged from 1.6 to 2.18 times BMR and compare well with estimates of DEEtot in the Northern Mockingbird (Mimus polyglottos), which is about the same size.
Dietary Changes and Poor Reproductive Performance in Glaucous-Winged Gulls
Authors: Murphy Edward C. , Day Robert H. , Oakley Karen L. , Hoover A. Anne
Published: September 2019

The breeding phenology of Glaucous-winged Gulls (Larus glaucescens) on Squab Island, Aialik Bay, Alaska in 1979 was identical to that in 1980, but clutch sizes and later reproductive performance differed markedly. In 1979, clutch sizes were small, but chick growth rates and survivorship were high. In contrast, clutch sizes were large in 1980, but chick growth rates were slow, and chick survivorship was extremely low. The different patterns of reproductive success appear to be related primarily to annual differences in foods utilized by adults. When adults fed primarily on blue mussels (Mytilus edulis), reproductive performance suffered, i.e. at the time of egg laying in 1979 and during the chick period in 1980. A switch to mussels from other prey types thus probably indicates a lack of availability of more suitable or preferred foods. Reproductive success at this colony appears to be strongly food limited; the timing of such limitation is not confined to a particular stage of reproduction.
The Thermal Environment and Its Constraint on Activity of Desert Quail in Summer
Authors: Goldstein David L.
Published: September 2019

I measured the thermal environments experienced by Gambel's Quail (Callipepla gambelii) during the summertime in the Colorado Desert by using estimates of standard operative temperature (Tes). Simultaneously with these measurements, I monitored the activity patterns of quail. The thermoneutral zone of freshly captured quail extends to 44°C, yet Tes in sunlit areas may exceed this upper critical temperature for more than 10 h of a hot day. Even in the shade, Tes is at the upper limits of thermoneutrality for much of the day. At these temperatures the birds maintain a body temperature that is very close to their upper lethal limit. The activity pattern of Gambel's Quail on hot summer days is bimodal, with morning and late afternoon foraging separated by a long quiescent period during midday. The time of onset and the duration of this inactive period varies directly with Tes and foraging occurs throughout the day on cool, overcast, summer days. This suggests that the thermal environment constrains midday activity. A bimodal activity pattern during the winter is probably a response to predation pressure from avian raptors. During the summer, however, it is advantageous for growing juvenile quail to maximize foraging, and the thermal environment is the most important factor shaping the activity schedule.
The Effects of Visibility Bias on Time-Budget Estimates of Niche Breadth and Overlap
Authors: Bradley David W.
Published: September 2019

Four time-budget estimation strategies are compared with respect to their sensitivity to two components of visibility bias in the observation process: discovery bias and loss bias. Monte Carlo simulations and a brief field study both indicate that visibility bias (particularly discovery bias) can substantially affect the results of time-budget studies. Estimators designed to curtail these biases performed best. Counting only initial contacts was least satisfactory. Bootstrap confidence intervals for niche overlap from the field study were so broad that overlap estimates seem nearly useless with very small sample sizes, such as the 93 observation series with 1,065 data points obtained here. Investigators who measure time or energy budgets in the field should take care to minimize sample biases, obtain adequate sample sizes, select analysis techniques appropriate for their sampling scheme, and confine inference to a scope compatible with the temporal and spatial scale of their study.
Densities of Antarctic Seabirds at Sea and the Presence of the Krill Euphausia superba
Authors: Obst Bryan S.
Published: September 2019

The antarctic krill Euphausia superba forms abundant, well-organized schools in the waters off the Antarctic Peninsula. Mean avian density is 2.6 times greater in waters where krill schools are present than in waters without krill schools. Seabird density is a good predictor of the presence of krill. Seabird density did not correlate with krill density or krill school depth. Disoriented krill routinely were observed swimming near the surface above submerged schools, providing potential prey for surface-feeding birds.

Responses of seabird species to the distribution of krill schools varied. The small to medium-size procellariiform species were the best indicators of krill schools; large procellariiforms and coastal species were poor indicators. Pygoscelis penguins occurred at high densities only in the presence of krill schools. These responses are consistent with the constraints imposed by the metabolic requirements and reproductive strategies of each of these groups.

Krill schools were detected near the sea surface throughout the day. Correlations between seabird density and the presence of krill during daylight hours suggest that diurnal foraging is important to the seabirds of this region.
Growth Rates of Cranes Reared in Captivity
Authors: Ricklefs Robert E. , Bruning Donald F. , Archibald George W.
Published: September 2019

We measured eggs, incubation periods, growth of chicks, and masses of adults of 10 species of cranes at the Bronx Zoo and the International Crane Foundation. Growth rate constants of Gompertz equations fitted to the data varied between 0.034 and 0.057/day. These values were 50-90% of those for altricial birds of comparable adult mass, and were considerably greater than those of other precocial species, such as galliforms. Rates of growth intermediate between altricial and precocial species are consistent with the fact that crane chicks, although precocial, are brooded and fed by their parents during much of the early development period.

Within species, asymptote (A) and growth-rate constant (K) of the Gompertz equations were negatively correlated, owing to their inherent relationship in the curve-fitting process. Masses of chicks during the first month after hatch were unrelated to the mass asymptote, but correlated strongly with the estimated growth-rate constant.

The mass of the neonate was about 60% of the fresh mass of the egg. Egg mass was unrelated to subsequent chick mass during the first month, but correlated with the mass asymptote in two species when the relationship between A and K was accounted for statistically. Egg mass also was correlated with incubation period, fledging period, and the growthrate constant in isolated instances.

Growth rate and asymptote among species were inversely related, as found among large samples of diverse bird species. The size of the egg relative to the mass of the adult was related inversely to adult mass, again consistent with patterns in other groups of birds. Fledging period was related strongly to the length of the incubation period and weakly to the asymptote to the growth curve, and it was unrelated to growth-rate constant of the Gompertz equation.
Seabird Patchiness in Tropical Oceanic Waters: The Influence of Sargassum “Reefs”
Authors: Haney J. Christopher
Published: September 2019

The relationships of seabirds to the holopelagic macroalga Sargassum were studied during a 2-yr survey in the South Atlantic Bight off the southeastern United States. Seabirds were significantly more abundant in waters with large (>5 m2) patches of the alga, and mean avian density was 32-43 times greater in waters where Sargassum was present than in adjacent waters without the alga. Seabirds aggregate at Sargassum patches formed by Langmuir circulation, convergence fronts, Gulf Stream eddies, and Gulf Stream warm core rings. Twenty-three seabird species foraged at Sargassum. Significantly more than 50% of White-tailed Tropicbirds (Phaethon lepturus), Masked Boobies (Sula dactylatra), and Bridled Terns (Sterna anaethetus) were observed at algal patches. Species that use aerial-dipping and plunge-diving foraging behaviors displayed the greatest affinity for Sargassum. Large-bodied seabirds (large shearwaters, tropicbirds, and boobies) generally were found at large patches, while small-bodied species (phalaropes and Puffinus lherminieri) occurred at smaller patches. The seasonal abundance of the pelagic Bridled Tern corresponded to seasonal variation in Sargassum abundance. Most seabirds associated with Sargassum for foraging, but Bridled and Black terns (Chlidonias niger) also used large algal mats for roost sites. The highly localized biomass of the pelagic Sargassum community and its associated motile macrofauna (zooplankton and fish) may allow seabirds to forage efficiently for prey in the oligotrophic surface waters of tropical marine environments. The patchy occurrence of Sargassum "reefs" may explain part of the local and mesoscale variation in seabird distribution and abundance in portions of the western North Atlantic Ocean.
Sources of Variation in Growth of Tree Swallows
Authors: Quinney Terry E. , Hussell David J. T. , Ankney C. Davison
Published: September 2019

We studied two populations of Tree Swallows (Tachycineta bicolor) that differed primarily in the amount of food available to the breeding birds. We obtained an index of food abundance and performed field experiments to distinguish factors affecting variability in growth of nestlings. The experiments were designed to detect the influence of the location of egg laying, incubation, and nestling rearing, type of parent (natural or foster), and year of breeding on nestling growth. Some broods were transferred between nests and raised by foster parents, and some clutches and broods were transferred between populations. Variables were analyzed in two- and three-way factorial analyses of variance.

The insect biomass index during the nestling period differed about 7-fold between locations, regardless of year of breeding. Nestlings with more food grew and survived better. Type of parent (i.e. natural or foster) or prehatch factors such as location of incubation did not influence growth. The location where nestlings were raised, however, explained as much as 51% of the variation in growth, and genetic variation in offspring and variation in provisioning abilities of parents may have been important components of within-population variation in growth regardless of where parents nested.
Ecology and Physiology of Fasting in King Penguin Chicks
Authors: Cherel Yves , Stahl Jean-Claude , Maho Yvon Le
Published: September 2019

Captive King Penguin (Aptenodytes patagonica) chicks can fast for 5 months during the subantarctic winter with a 70% decrease in body mass. To investigate the adaptive value of this remarkable resistance to starvation, we compared captive chicks with free-ranging chicks in their colony at Possession Island, Crozet Archipelago. The chicks in the colony, from mid-April to beginning of September (i.e. all winter) were fed only every 39 days by their parents; some were not fed at all. In spring (October-December) the surviving chicks were fed every 6 days, and their growth was completed. Overall chick mortality in the colony during the winter and subsequent spring was about 50%. Mortality was highest in October, 6 months after the beginning of the winter, and may be attributed mainly to starvation. The decrease in body mass in the free-ranging chicks was remarkably similar to that for captive birds. In both groups, three periods were characterized according to the observed changes in the daily decrease in body mass per unit body mass (dm/mdt): dm/mdt dropped during the first period (I) of 5-6 days, was minimum and steady during period II, which lasted about 4 months, and increased in period III. Blood analysis of the captive chicks indicated the three periods correspond to modifications in protein breakdown. An initial decrease in uricacidemia indicates period I is a short period of transition, marked by a decrease in protein breakdown. In period II a minimum and constant uricacidemia, in parallel with a progressive increase in ketonemia, indicates efficient protein sparing while most of the energy is derived from lipids. Period III is critical because, from a rise in uricacidemia concomitant with a decreasing ketonemia, proteins are no longer spared. The extreme resistance of King Penguin chicks to starvation in winter may be explained partly by the ability to spare proteins for several months (period II). It occurs at a growth stage when the parents' feeding visits are rare. Other laboratory and field investigations of birds suggest that the means by which a wide variety of domestic and wild species adapt to fasting also may be interpreted in terms of three periods corresponding to changes in protein breakdown.
Feeding and Nesting Ecology of Sympatric South Polar and Brown Skuas
Authors: Pietz Pamela J.
Published: September 2019

In the 1979-1980 and 1980-1981 austral summers, I examined nesting and feeding ecology of South Polar (Catharacta maccormicki) and Brown (C. lonnbergi) skuas near Palmer Station, Antarctica. As earlier studies had suggested, South Polar Skuas fed mostly at sea on fish, and Brown Skuas fed mostly on penguin eggs and chicks. These dietary differences correlated with differences in the skuas' time budgets, activity patterns, territory types, breeding chronologies, nest densities, clutch sizes, and fledging success. With combined data from this and other studies at Palmer, I calculated average productivity for both species over 7 breeding seasons. Brown Skuas fledged higher and more consistent numbers of young per pair, probably because of their more accessible and reliable food source.
A Classification of the Living Birds of the World Based on Dna-Dna Hybridization Studies
Authors: Sibley Charles G. , Ahlquist Jon E. , Monroe Burt L.
Published: September 2019

We present a classification of the living birds of the world based on the results of DNA-DNA hybridization studies. Several family-group names are presented formally for the first time; some of these names have appeared earlier in various publications.
Molt in the Annual Cycle of Canvasbacks
Authors: Lovvorn James R. , Barzen Jeb A.
Published: September 2019

We studied the intensity of molt of capital, down, and contour plumages of male and female Canvasbacks (Aythya valisineria) from late fall through winter, spring migration, and nesting. Molt intensities in both juvenile and adult males were highest among arriving fall migrants and during prewinter fat deposition, and molt in juvenile males increased during early spring migration. Among females, capital molt was high among arriving migrants in fall, and molt of all plumage types increased during spring migration and courtship. Paired females tended to molt more heavily than unpaired females during spring migration, but many females initiated intensive prebasic molt before pairing. Molt in females peaked in spring migration and early breeding, concurrently with accelerated fat storage and ovarian growth. Capital and contour molt in females decreased during laying and essentially ceased during incubation, perhaps to mitigate energetic constraints during these periods. Prewinter nutrient storage appeared independent of molt intensity, except for body protein among juveniles. During spring migration, molt intensities were greater in adult females with higher levels of body fat and protein, indicating that molt did not necessarily precede or interfere with nutrient storage. We suggest that outside the laying, incubation, and wing molt periods, the energetic costs of molt in Canvasbacks are not sufficient to mandate temporal separation of molt from nutrient storage, migration, courtship, or early stages of rapid ovarian growth.