bluuebunny/crossref_metadata_2025_split huggingface dataset:
Salt Water Tolerance and Water Turnover in the Snowy Plover
Authors: Purdue James R. , Haines Howard 
Published: July 2020

Abstract
A series of water-related experiments showed that Snowy Plovers do not have any outstanding physiological capabilities for dealing with the potential thermal and osmotic stresses of the Great Salt Plains, Oklahoma. Snowy Plovers and Semipalmated Sandpipers failed to maintain body weight when given 0.3 M NaCl ad libitum. Killdeer did even more poorly by rapidly losing weight on 0.2 M. These salt water tolerance values are limited when compared to other, particularly marine, birds that can drink full strength sea water. The Snowy Plover is no better at conserving water than other birds in its weight class. So plovers without drinking water were able to maintain their weight when furnished mealworm larvae ad libitum, the insectivorous diet as well as maintenance behavior of the birds is essential for their survival on the salt flats.
Nestling Biology of the Field Sparrow
Authors: Best Louis B. 
Published: July 2020

Abstract
The biology of Field Sparrow nestlings was studied during two breeding seasons in central Illinois, on a 23.6-ha tract composed of mixed vegetation. Predominant nestling foods were lepidopteran larvae, orthopteran nymphs, homopterans, and spiders. Foods given to nestlings ranged in size from less than 0.005 cc to 0.38 cc, the upper size limit increasing with nestling age. The food size class most frequently fed to the young contained items smaller than 0.05 cc, although its importance decreased as the nestlings grew older. Girth rather than length limited the size of food the young successfully ingested. The number of feeding trips per hour to 6-day-old broods ranged from 0 to 21 and averaged 9, divided about equally between male and female. The feeding frequency peaked shortly after dawn and just before dusk, and was lowest near midday. There was a significant inverse relationship between the female feeding rate and brooding time. Ambient temperature significantly influenced brooding time, with the least brooding at 60° to 69°F. The rate of feeding individual nestlings decreased slightly (nonsignificant) as brood size increased. The overall nestling growth rate index (weight) averaged 0.568, and ranged 0.444 to 0.712. No nestling starvation was evident. The rate of weight gain in broods of four was significantly higher during early summer than late summer, while broods of three showed a significant opposite trend. The dependence of thermoregulatory maintenance costs upon brood size is discussed. Growth rates of the youngest nestlings were significantly less than those of their siblings. It was concluded that Field Sparrows forage opportunistically for their nestlings, and that food availability did not limit breeding success on the study tract.
Differential Response of Territorial Yellowthroats to the Songs of Neighbors and Non-neighbors
Authors: Wunderle Joseph M. 
Published: July 2020

Abstract
Songs of neighbor and non-neighboring individual Yellowthroats were presented to territorial male Yellowthroats in two different locations within the territory. Territorial males showed a significantly higher aggressive response to the songs of strangers than neighbors when the speaker was placed near the respective neighbor's boundary. Presentation of the two songs in the center of a territory resulted in a high aggressive response to both songs, with no discernable difference in response. Evidence is also presented that suggests that females are capable of recognizing their mates by song alone.
Breeding Cycle and Behavior of the Semipalmated Sandpiper at Barrow, Alaska
Authors: Ashkenazie Shoshana , Safriel Uriel N. 
Published: July 2020

Abstract
Pair formation of Calidris pusilla near Barrow, Alaska occurs 3-6 days after the territory is established. The pair is then engaged in nest scraping displays during 2-3 days, in which 10-12 scrapes are made by the male and examined by the female. Eventually 2-3 scrapes are lined by the female, and in one of these the first egg is laid 4-6 days after pairing. During the egg-laying period further lining is performed by the female and partial incubation takes place by both sexes. Continuous incubation commences 8 h prior to laying of the 4th egg. Male and female alternate in incubation: in the first 2 days a turn lasts 3-5 h, and the duration gradually increases up to 13-14 h during the 2nd week. Long incubation turns reduce the number of approaches to the nest and may therefore reduce the chances of it being discovered by predators. The incubating bird is intermittently engaged in egg-rolling and in camouflaging the nest by bending adjacent grass blades over its back, and is constantly alert. The off-duty bird may feed 2-3 km away from the nest. The eggs hatch after 20 days of incubation, all within 1 day. Females desert the family 2-8 days after hatching: they desert late if hatching is early, and early if hatching is late in the season. After female departure the family moves from the nesting territory, typically in a high-centered polygonal area, to establish a home range as far as 2-3 km away, often in a low-centered polygonal area. During the first 6-8 days after hatching, the male prepares each evening a scrape for night brooding. After fledging, the male and young join wandering flocks.
Guilds and Community Organization: Analysis of an Oak Woodland Avifauna in Sonora, Mexico
Authors: Landres Peter B. , MacMahon James A. 
Published: July 2020

Abstract
Community organization of an oak woodland breeding avifauna was studied in Sonora, Mexico. Species were classified into guilds by quantifying foraging behavior, based on investigator-defined resource classes, and subjecting these data to cluster analysis. From this analysis five guilds were recognized: foliage gleaning, wood gleaning, wood probing, air sallying, and ground sallying. Within each resource class all guilds foraged in a significantly different manner, except for air and ground salliers.
Species within guilds were most often separated by food-site and perch height. Use of height classes by the avian community was significantly different from the quantity of tree vegetation per height class. Differential height utilization generally resulted from gleaning and probing guilds foraging at upper heights and sallying guilds foraging at lower heights. Ecological separation within and among guilds is discussed and related to community organization in this oak woodland avifauna. When the guild structure of this community is compared to other oak woodland avifaunas, a decrease in foliage gleaners of nearly 2.5-fold and a 6.4-fold increase in salliers occur from Oregon to Sonora, Mexico. Utility of the guild approach is discussed in relation to some prominent questions raised by results of the above comparison concerning (1) foraging plasticity in species coexistence and (2) change in community structure over time and between geographic locations.
Extramarital and Pair Copulations in the Cattle Egret
Authors: Fujioka Masahiro , Yamagishi Satoshi 
Published: July 2020

Abstract
The copulatory behavior of the Cattle Egret (Bubulcus ibis) was observed in a heronry in central Japan. In 38 of 147 extramarital copulation (EC) attempts with seven females, the males seemed in ejaculation. There were relatively few complete ECs prior to egg laying, because females responded aggressively to approaching males and because the mates of the females stayed in the territories for 78.8% of the time and protected the females. After egg laying, the aggressiveness of females against approaching males decreased and their mates spent more time outside the territories, resulting in an increase in the occurrence of complete ECs. Fighting males that were approaching a female exhibited a dominance hierarchy. The most dominant male stayed in the territory for the longest time and copulated most intensively with his mate and other neighboring females.
Extramarital copulations are likely to occur in colonial herons, but mate-guarding by the male and aggression by the female mate enhance the probability that copulations will be performed only between members of the pair during the fertilizable period of the female. Thus, the monogamous pair bond is maintained.
Acoustical Location of Prey by the Marsh Hawk: Adaptation to Concealed Prey
Authors: Rice William R. 
Published: July 2020

Abstract
The ability of Marsh Hawks (Circus cyaneus) to locate prey acoustically was measured in both the laboratory and the field. Laboratory experiments indicated that the directional hearing of the Marsh Hawk was substantially better than that of a sample of typical diurnal raptors and similar to that of owls capable of capturing prey in total darkness. Angular resolution along the horizontal axis was 2° for the Marsh Hawks, 1-2° for the owls, and 8-12° for the sample of typical diurnal raptors. For the Marsh Hawks, angular resolution along the vertical axis was at least 2°. The maximum range at which prey could be detected by sound was estimated to be 3-4 m for the Marsh Hawk and 7 m for the Barn Owl (Tyto alba). Field experiments indicated that free-ranging Marsh Hawks could locate vole vocalizations (squeaks) accurately and attack prey successfully without the aid of visual or olfactory cues. Additional field experiments were conducted to determine how the Marsh Hawk integrates auditory and visual cues while capturing concealed prey. These experiments show that the Marsh Hawk does not require motion cues or auditory depth perception to determine the elevation of a sound source.
A Test for Conspecific Egg Discrimination in Three Species of Colonial Passerine Birds
Authors: Lanier Glen A. 
Published: July 2020

Abstract
Naturally occurring populations of three species of colonial passerine birds, the Piñon Jay (Gymnorhinus cyanocephalus), Great-tailed Grackle (Quiscalis mexicanus), and Barn Swallow (Hirundo rustica), were tested for conspecific egg discrimination and the presence of intraspecific brood parasitism that such discrimination would imply. Current theory predicts that intraspecific brood parasitism, or cheating, might occur when a brood parasite's fitness is enhanced relative to a nonparasite's. Due to the high cost of parental care in altricial birds, selection for defenses against such cheaters should also be intense. Egg rejection is the most common selection mechanism against interspecific brood parasites, and I tested for the presence or absence of this mechanism.
Single eggs were switched between pairs of 19 Piñon Jay nests, 15 Great-tailed Grackle nests, and 14 Barn Swallow nests, and a fifth egg was added to each of 8 Piñon Jay nests. No significant level of rejection of introduced eggs was found, possibly either because the cost of cheating is too great or because egg discrimination and rejection are not the mechanisms of selection against cheaters in the populations tested.
A divide-and-conquer method for sparse risk prediction and evaluation
Authors: Hong Chuan , Wang Yan , Cai Tianxi 
Published: July 2020

SummaryDivide-and-conquer (DAC) is a commonly used strategy to overcome the challenges of extraordinarily large data, by first breaking the dataset into series of data blocks, then combining results from individual data blocks to obtain a final estimation. Various DAC algorithms have been proposed to fit a sparse predictive regression model in the $L_1$ regularization setting. However, many existing DAC algorithms remain computationally intensive when sample size and number of candidate predictors are both large. In addition, no existing DAC procedures provide inference for quantifying the accuracy of risk prediction models. In this article, we propose a screening and one-step linearization infused DAC (SOLID) algorithm to fit sparse logistic regression to massive datasets, by integrating the DAC strategy with a screening step and sequences of linearization. This enables us to maximize the likelihood with only selected covariates and perform penalized estimation via a fast approximation to the likelihood. To assess the accuracy of a predictive regression model, we develop a modified cross-validation (MCV) that utilizes the side products of the SOLID, substantially reducing the computational burden. Compared with existing DAC methods, the MCV procedure is the first to make inference on accuracy. Extensive simulation studies suggest that the proposed SOLID and MCV procedures substantially outperform the existing methods with respect to computational speed and achieve similar statistical efficiency as the full sample-based estimator. We also demonstrate that the proposed inference procedure provides valid interval estimators. We apply the proposed SOLID procedure to develop and validate a classification model for disease diagnosis using narrative clinical notes based on electronic medical record data from Partners HealthCare.
Aging Effects on the Neuroplastic Attributes of Multisensory Cortical Networks as Triggered by a Computerized Music Reading Training Intervention
Authors: Paraskevopoulos Evangelos , Chalas Nikolas , Karagiorgis Alexandros , Karagianni Maria , Styliadis Charis , Papadelis Georgios , Bamidis Panagiotis 
Published: July 2020

AbstractThe constant increase in the graying population is the result of a great expansion of life expectancy. A smaller expansion of healthy cognitive and brain functioning diminishes the gains achieved by longevity. Music training, as a special case of multisensory learning, may induce restorative neuroplasticity in older ages. The current study aimed to explore aging effects on the cortical network supporting multisensory cognition and to define aging effects on the network’s neuroplastic attributes. A computer-based music reading protocol was developed and evaluated via electroencephalography measurements pre- and post-training on young and older adults. Results revealed that multisensory integration is performed via diverse strategies in the two groups: Older adults employ higher-order supramodal areas to a greater extent than lower level perceptual regions, in contrast to younger adults, indicating an age-related shift in the weight of each processing strategy. Restorative neuroplasticity was revealed in the left inferior frontal gyrus and right medial temporal gyrus, as a result of the training, while task-related reorganization of cortical connectivity was obstructed in the group of older adults, probably due to systemic maturation mechanisms. On the contrary, younger adults significantly increased functional connectivity among the regions supporting multisensory integration.
Gaps in Sexually Transmitted Infection Screening Among Men who Have Sex with Men in Pre-exposure Prophylaxis (PrEP) Care in the United States
Authors: Chandra Christina , Weiss Kevin M , Kelley Colleen F , Marcus Julia L , Jenness Samuel M 
Published: July 2020

Abstract

Background
The US Centers for Disease Control and Prevention (CDC) recommends comprehensive sexually transmitted infection (STI) screening every 3–6 months for men who have sex with men (MSM) using human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP). The gaps between these recommendations and clinical practice by region have not been quantified.

Methods
We used survey data collected from the internet-based ARTnet study between 2017 and 2019 on STI screening among MSM across the United States, stratified by current, prior, and never PrEP use. Poisson regression models with robust error variance were used to model factors, including residence in the Southeast, associated with consistent (“always” or “sometimes”) exposure site-specific STI screening during PrEP care.

Results
Of 3259 HIV-negative MSM, 19% were currently using PrEP, 6% had used PrEP in the past, and 75% had never used PrEP. Among ever PrEP users, 87%, 78%, 57%, and 64% reported consistent screening for STIs by blood sample, urine sample or urethral swab, rectal swab, or pharyngeal swab, respectively, during PrEP care. Compared to PrEP users in all other regions, PrEP users in the Southeast were significantly less likely to be consistently screened for urogenital (adjusted prevalence ratio [aPR], 0.86; 95% confidence interval [CI], .76–.98) and rectal STIs (aPR, 0.76; 95% CI, .62–.93) during PrEP care.

Conclusions
Substantial gaps exist between CDC recommendations for STI screening during PrEP care and current clinical practice, particularly for rectal and pharyngeal exposure sites that can harbor asymptomatic infections and for MSM in Southeast states where the STI burden is substantial.
Plasma Homocysteine Is Weakly Correlated with Plasma Endothelin and von Willebrand Factor but not with Endothelium-dependent Vasodilatation in Healthy Postmenopausal Women
Authors: de Valk-de Roo Gerdien W , Stehouwer Coen DA , Lambert Jan , Schalkwijk Casper G , van der Mooren Marius J , Kluft Cornelis , Netelenbos Coen 
Published: July 2020

Abstract
Background: Hyperhomocysteinemia is an independent cardiovascular risk factor, possibly through the induction of endothelial dysfunction. The postmenopausal state is associated with increased plasma homocysteine. We examined whether increased homocysteine is associated with impaired endothelial function.
Methods: Sixty-three hysterectomized but otherwise healthy postmenopausal women (54.8 ± 3.5 years) participated in this study. Fasting total plasma homocysteine (tHcy) was measured as free plus protein-bound homocysteine. Endothelial function was assessed by measuring plasma concentrations of the endothelium-derived proteins endothelin (ET), von Willebrand factor (vWF), and plasminogen activator inhibitor type 1 (PAI-1) as well as brachial artery flow-mediated, endothelium-dependent vasodilatation (FMD).
Results: Plasma tHcy was 9.6 ± 2.5 μmol/L. After adjustment for possible confounders, a 1 μmol/L increase in tHcy was associated with an increase in ET of 0.08 ng/L (P = 0.045) and an increase in vWF of 4.2% (P = 0.05). No statistically significant association was present between tHcy and PAI-1 or FMD.
Conclusions: Increased fasting homocysteine in postmenopausal women may impair some aspects of endothelial function. It is of clinical interest to study whether homocysteine lowering can improve endothelial function and thus cardiovascular morbidity and mortality in postmenopausal women.
Gender Differences in Diurnal Growth Hormone and Epinephrine Values in Young Adults during Ambulation
Authors: Edén Engström Britt , Karlsson F Anders , Wide Leif 
Published: July 2020

Abstract
Background: In the present study, the impact of gender, oral contraceptives, and ambulation on serum growth hormone (GH) and urinary catecholamines was examined in healthy young adults.
Methods: Twenty-one medical student volunteers—7 men, 7 women, and 7 women taking oral contraceptives—were investigated. Serum samples were drawn every second hour during a 24-h period. At 0800 the first morning, serum samples were drawn while subjects were in the ambulatory state; the next morning, serum samples were drawn at 0800 while the subjects were still resting in bed.
Results: During the daytime, GH concentrations were sevenfold higher in the women than in the men, a difference larger than described previously. During the night, there was no gender difference. In the morning, ambulatory GH concentrations were 28-fold higher in the women than in the men, whereas supine GH concentrations were only 4.6-fold higher in the women than in the men. Daytime urinary output of epinephrine was lower in the women than in the men, whereas there was no difference at night. Women using estrogen-containing oral contraceptives had lower epinephrine and higher GH values than women not taking oral contraceptives. In women, morning GH concentrations were higher in the ambulatory than in the resting state, whereas they were lower in the ambulatory state than in the resting state in men.
Conclusions: The secretion of GH and epinephrine is gender-dependent and differs during the daytime in a reciprocal manner, with higher GH and lower epinephrine in women than in men. Oral contraceptives appear to further increase such differences. It seems likely that the data reflect a gender difference in the utilization of substrates for energy production.
Serum Insulin-like Growth Factors and Insulin-like Growth Factor-binding Proteins: Clinical Implications
Authors: Rosen Clifford J 
Published: July 2020

AbstractThe last decade has been characterized by a major investigative thrust into the physiology of two unique but ubiquitous peptides, insulin-like growth factor (IGF)-I and IGF-II. The regulatory systems that control the tissue bioactivity of the IGFs have been delineated, and subcellular signaling mechanisms have been clarified. Clearly, both tissue and circulating growth factor concentrations are important in defining the relationship between IGF-I and cell activity. Bone, liver, and circulatory IGF-I have received the most attention by investigators, in part because of the ease of measurement and the interaction with disease states such as osteoporosis. More recently, attention has focused on the role IGF-I plays in neoplastic transformation and growth. Two large prospective observational studies have demonstrated greater risk for prostate and breast cancer associated with high circulating concentrations of IGF-I. Animal models and in vitro studies confirm that there is a close, albeit complex, interaction between IGF-I signaling and bone turnover. This report will focus on: (a) IGF physiology, including IGF ligands, binding proteins, and proteases; (b) the relationship between IGF-I and bone mass in respect to risk for osteoporosis; (c) the heritable regulation of the IGF-I phenotype; and (d) the association between serum IGF-I and cancer risk. The IGFs remain a major area for basic and clinical investigations; future studies may define both diagnostic and therapeutic roles for these peptides or their related proteins in several disease states.
Total and Free Deoxypyridinoline after Acute Osteoclast Activity Inhibition
Authors: Rubinacci Alessandro , Melzi Raffaella , Zampino Maria , Soldarini Armando , Villa Isabella 
Published: July 2020

AbstractBackground: Deoxypyridinoline (Dpd) is one of the two pyridinium cross-links that provide structural rigidity to type I collagen in bone. During osteoclastic resorption, Dpd is released into circulation and is excreted in the urine in free and peptide-bound forms. Free and total Dpd are highly correlated, but whether the free-to-total cross-link ratio is constant in both normal and high bone turnover states remains controversial. To compare free and total Dpd performance in a physiological condition, urinary free and total Dpd were measured after a short-term inhibition of osteoclast activity such as that induced by an oral calcium load.Methods: Total and free Dpd were measured by HPLC and by immunosorbent assay, respectively, in two groups of subjects, one (calcium-treated; n = 16) taking calcium and the other not (control; n = 9).Results: The urinary excretion of total Dpd at 2 and 4 h after oral calcium loading was decreased compared with controls. By contrast, changes in free Dpd were similar in the calcium-treated and control groups, reflecting only circadian rhythm.Conclusions: Total and free Dpd do not show comparable sensitivity in detecting short-term inhibition of osteoclast activity. The degradation process of peptide-bound to free Dpd could render free Dpd insensitive to acute changes of osteoclast activity.