bluuebunny/crossref_metadata_2025_split huggingface dataset:
The balanced radiative effect of tropical anvil clouds
Authors: Hartmann Dennis L. , Berry Sara E. 
Published: April 2017

AbstractCoincident instantaneous broadband radiation budget measurements from Clouds and Earth's Radiant Energy System and cloud vertical structure information from CloudSat‐Cloud‐Aerosol Lidar and Infrared Pathfinder Satellite Observations radar‐lidar observations are combined to study the relationship of cloud vertical structure to top‐of‐atmosphere energy balance fluctuations. Varying optical and physical thickness of high ice clouds produces most of the covariation between albedo and outgoing longwave radiation in regions of tropical convection. Rainy cores of tropical convective clouds have a negative impact on the radiation balance, while nonprecipitating anvil clouds have a positive effect. The effect of anvil clouds on the radiative heating profile is to warm near cloud base and cool near cloud top, and to reduce the radiative cooling rate in the clear air below the cloud. The cooling rate in the clear air below the anvil is reduced to small values for moderately thick anvils, and the driving of instability in the anvil itself also saturates for relatively thin clouds. It is hypothesized that the dependence of radiative heating on cloud thickness may be important in driving the distribution of tropical cloud structures toward one that produces net neutrality of the cloud radiative effect at the top‐of‐the‐atmosphere, as is found in regions of deep convection over ocean areas with high and relatively uniform surface temperatures. This idea is tested with a single‐column model, which indicates that cloud‐radiation interactions affect anvil cloud properties, encouraging further investigation of the hypothesis.
Measuring ionizing radiation in the atmosphere with a new balloon‐borne detector
Authors: Aplin K. L. , Briggs A. A. , Harrison R. G. , Marlton G. J. 
Published: April 2017

AbstractIncreasing interest in energetic particle effects on weather and climate has motivated development of a miniature scintillator‐based detector intended for deployment on meteorological radiosondes or unmanned airborne vehicles. The detector was calibrated with laboratory gamma sources up to 1.3 MeV and known gamma peaks from natural radioactivity of up to 2.6 MeV. The specifications of our device in combination with the performance of similar devices suggest that it will respond to up to 17 MeV gamma rays. Laboratory tests show that the detector can measure muons at the surface, and it is also expected to respond to other ionizing radiation including, for example, protons, electrons (>100 keV), and energetic helium nuclei from cosmic rays or during space weather events. Its estimated counting error is ±10%. Recent tests, when the detector was integrated with a meteorological radiosonde system and carried on a balloon to ~25 km altitude, identified the transition region between energetic particles near the surface, which are dominated by terrestrial gamma emissions, to higher‐energy particles in the free troposphere.
Physical activity predicts reduced plasma β amyloid in the Cardiovascular Health Study
Authors: Stillman Chelsea M. , Lopez Oscar L. , Becker James T. , Kuller Lewis H. , Mehta Pankaj D. , Tracy Russell P. , Erickson Kirk I. 
Published: April 2017

AbstractObjectiveHigher levels of physical activity (PA) reduce the risk of cognitive impairment, but the underlying mechanisms are unclear. Using longitudinal data from the Cardiovascular Health Study, we examined whether PA predicted plasma Aβ levels and risk for cognitive decline 9–13 years later.MethodsLinear and logistic regressions (controlling for APOE status, age, gender, body mass index, cardiovascular disease, brain white matter lesions, and cystatin C levels) tested associations between PA, Aβ, and cognitive impairment in a sample of 149 cognitively normal older adults (mean age 83 years).ResultsMore PA at baseline predicted lower levels of Aβ 9–13 years later. Higher Aβ levels at year 9 predicted greater risk for cognitive impairment at year 13. Levels of Aβ at year 9 mediated the relationship between PA and cognitive impairment.InterpretationGreater PA may reduce plasma levels of a neurotoxic peptide at an age when the risk for cognitive impairment is especially high.
Copper(I) Oxide/N,N′‐Bis[(2‐furyl)methyl]oxalamide‐Catalyzed Coupling of (Hetero)aryl Halides and Nitrogen Heterocycles at Low Catalytic Loading
Authors: Pawar Govind Goroba , Wu Haibo , De Subhadip , Ma Dawei 
Published: April 2017

AbstractAn easily prepared oxalic diamide is a powerful ligand for the copper‐catalyzed coupling of aryl halides with nitrogen heterocycles. Only 1–2 mol% each of copper(I) oxide and N,N′‐bis[(2‐furyl)methyl]oxalamide (BFMO) are needed to form N‐arylation products under mild conditions. More than 10 different types of nitrogen heterocycles are compatible with these conditions, thereby giving the corresponding N‐arylation products.magnified image
Global exosome transcriptome profiling reveals biomarkers for multiple sclerosis
Authors: Selmaj Igor , Cichalewska Maria , Namiecinska Magdalena , Galazka Grazyna , Horzelski Wojciech , Selmaj Krzysztof W. , Mycko Marcin P. 
Published: April 2017

ObjectiveAccumulating evidence supports a role for exosomes in immune regulation. In this study, we investigated the total circulating exosome transcriptome in relapsing–remitting multiple sclerosis (RRMS) patients and healthy controls (HC).MethodsNext generation sequencing (NGS) was used to define the global RNA profile of serum exosomes in 19 RRMS patients (9 in relapse, 10 in remission) and 10 HC. We analyzed 5 million reads and >50,000 transcripts per sample, including a detailed analysis of microRNAs (miRNAs) differentially expressed in RRMS. The discovery set data were validated by quantification using digital quantitative polymerase chain reaction with an independent cohort of 63 RRMS patients (33 in relapse, 30 in remission) and 32 HC.ResultsExosomal RNA NGS revealed that of 15 different classes of transcripts detected, 4 circulating exosomal sequences within the miRNA category were differentially expressed in RRMS patients versus HC: hsa‐miR‐122‐5p, hsa‐miR‐196b‐5p, hsa‐miR‐301a‐3p, and hsa‐miR‐532‐5p. Serum exosomal expression of these miRNAs was significantly decreased during relapse in RRMS. These miRNAs were also decreased in patients with a gadolinium enhancement on brain magnetic resonance imaging. In vitro secretion of these miRNAs by peripheral blood mononuclear cells was also significantly impaired in RRMS.InterpretationThese data show that circulating exosomes have a distinct RNA profile in RRMS. Because putative targets for these miRNAs include the signal transducer and activator of transcription 3 and the cell cycle regulator aryl hydrocarbon receptor, the data suggest a disturbed cell‐to‐cell communication in this disease. Thus, exosomal miRNAs might represent a useful biomarker to distinguish multiple sclerosis relapse. Ann Neurol 2017;81:703–717
Mechanical Constraints on the Hominin Pelvis and the “Obstetrical Dilemma”
Authors: Ruff Christopher 
Published: April 2017

ABSTRACTThe “obstetrical dilemma” posits that increases in birth canal dimensions during hominin evolution were constrained by mechanical factors associated with bipedal gait. This model has recently been challenged, in part on the basis of experimental data showing little association between pelvic and proximal femoral dimensions and locomotor costs among human experimental subjects. However, complete rejection of the model is premature, for two reasons: (1) it is difficult to extrapolate experimental results to naturalistic conditions and the much more varied body form and possibly locomotor style of early hominins. Relative pelvic breadth and femoral neck length in both australopiths and early Homo are at or beyond the limits observed among modern humans, and there is evidence that australopiths may have used an altered form of bipedal gait. (2) Other mechanical factors in addition to locomotor cost are important when assessing pelvic and proximal femoral morphology. Increasing biacetabular breadth increases the joint reaction force (JRF) on the femoral head. Increasing femoral neck length may reduce hip JRF, but also increases stress and fracture risk in the femoral neck. Increasing both biacetabular breadth and femoral neck length also increases mediolateral bending stress in the proximal femoral shaft, necessitating substantial buttressing of the diaphysis. Thus, there are mechanical consequences beyond simply locomotor costs that must be considered when evaluating variation in pelvic and femoral morphology among past and extant hominins. Anat Rec, 300:946–955, 2017. © 2017 Wiley Periodicals, Inc.
Ischial Form as an Indicator of Bipedal Kinematics in Early Hominins: A Test Using Extant Anthropoids
Authors: Lewton Kristi L. , Scott Jeremiah E. 
Published: April 2017

ABSTRACTHuman ischia contrast with those of great apes in being craniocaudally short and dorsally projecting. This configuration is thought to facilitate greater hip extension in humans during bipedal locomotion. This link has been used to infer kinematics in early hominins, but the consequences of variation in ischial configuration for gait remain uncertain. Kinematic data for a limited sample of extant nonhuman primates demonstrate that there is variation in hip extension in these taxa during bipedal behaviors—specifically, Hylobates and Ateles are capable of greater extension than Pan and Macaca. In this study, we tested the hypothesis that ischial length and orientation are functionally linked with hip extension during bipedalism among these taxa. As expected, humans have the shortest ischia, followed by gibbons, spider monkeys, chimpanzees, and macaques. Our predictions for ischial orientation are not supported, however: macaques, gibbons, and spider monkeys do not vary in this trait, and they have ischia that are less dorsally angled than that of the chimpanzee. The results for ischium length provide limited support for the idea that the early hominin Ardipithecus ramidus, with its long, caudally oriented ischium was not capable of humanlike extended‐hip bipedalism, and that the ischial shortening observed in post‐Ardipithecus hominins reflects a shift toward a more humanlike gait. In contrast, while our results do not necessarily refute a link between ischial orientation and hip extension in hominins, they do not provide comparative support, making changes in ischial orientation in this part of the fossil record more difficult to interpret. Anat Rec, 300:845–858, 2017. © 2017 Wiley Periodicals, Inc.
Lower Ilium Evolution in Apes and Hominins
Authors: Hammond Ashley S. , Almécija Sergio 
Published: April 2017

ABSTRACTElucidating the pelvic morphology of the Pan‐Homo last common ancestor (LCA) is crucial for understanding ape and human evolution. The pelvis of Ardipithecus ramidus has been the basis of controversial interpretations of the LCA pelvis. In particular, it was proposed that the lower ilium became elongate independently in the orangutan and chimpanzee clades, making these taxa poor analogues for the pelvis of the LCA. This study examines the variation in relative lower ilium height between and within living and fossil hominoid species (and other anthropoids), and models its evolution using available fossil hominoids as calibration points. We find nuanced differences in relative lower ilium height among living hominoids, particularly in regards to gorillas, which do not have elongate lower ilia (because they are likely to represent the plesiomorphic hominoid condition for this trait). We also show that differences in relative lower ilium height among hominoid taxa are not readily explained by differences in size between species. Our maximum likelihood ancestral state reconstructions support inferences that chimpanzees (Pan troglodytes in particular) and orangutans evolved their elongate lower ilia independently. We also find that the predicted lower ilium height of the Pan‐Homo LCA is shorter than all great apes except gorillas. This study adds to a growing body of evidence that finds different regions of the body show different evolutionary histories in different hominoids, and underscores that the unique combinations of morphologies of each modern and fossil hominoid species should be considered when reconstructing the mosaic nature of the Pan‐Homo LCA. Anat Rec, 300:828–844, 2017. © 2017 Wiley Periodicals, Inc.
Sacral Variability in Tailless Species: Homo sapiens and Ochotona princeps
Authors: Tague Robert G. 
Published: April 2017

ABSTRACTHomo sapiens is variable in number of sacral vertebrae, and this variability can lead to obstetrical complication. This study uses the comparative method to test the hypothesis that sacral variability in H. sapiens is associated with absence of a tail. Three species of lagomorphs are studied: Ochotona princeps (N = 271), which is tailless, and Lepus californicus (N = 212) and Sylvilagus audubonii (N = 206), which have tails. Results show that O. princeps has (1) higher diversity index for number of sacral vertebrae (0.49) compared to L. californicus (0.25) and S. audubonii (0.26) and (2) significantly higher percentage of individuals with the species‐specific nonmodal number of sacral vertebrae (43.9%) compared to L. californicus (14.2%) and S. audubonii (15.5%). Comparison of H. sapiens (N = 1,030; individuals of age 20–39 years) with O. princeps shows similarities between the species in diversity index (also 0.49 in H. sapiens) and percentage of individuals with nonmodal number of sacral vertebrae (37.3% in H. sapiens). Homeotic transformation best explains the results. H. sapiens and O. princeps show propensity for caudal shift at the sacral–caudal border (i.e., homeotic transformation of the first caudal vertebra to a sacral vertebra). Caudal and cranial shift among presacral vertebrae increases or decreases this propensity, respectively. Increase in number of sacral vertebrae in H. sapiens by homeotic transformation reduces pelvic outlet capacity and can be obstetrically hazardous. Anat Rec, 300:798–809, 2017. © 2017 Wiley Periodicals, Inc.
Development of Pelvic Sexual Dimorphism in Hylobatids: Testing the Obstetric Constraints Hypothesis
Authors: Zollikofer Christoph P.E. , Scherrer Marc , Ponce de León Marcia S. 
Published: April 2017

ABSTRACTPelvic sexual dimorphism in primates is typically seen as the result of female‐specific adaptations to obstetric constraints, which arise from the tight fit between the neonate head and the maternal pelvis. However, it remains debated to which extent pelvic dimorphism is a correlate of obstetric constraints, of body size dimorphism, and/or of other factors. Also, little is known on how pelvic dimorphism develops. Here we use methods of biomedical imaging and geometric morphometrics to address these questions in two hylobatid species,Hylobates larandSymphalangus syndactylus. These species differ markedly in body size, but within each species, there is only little body size dimorphism. Results show that the neonates ofH. larare large compared to the maternal pelvis, resulting in high cephalopelvic proportions and substantial obstetric constraints. Pelvic sexual dimorphism is moderate but significant: During puberty, females develop a more capacious pelvic inlet than males, while overall pelvic size is similar in both sexes.S. syndactylushas substantially larger pelves thanH. lar, but neonates are similar in size to those ofH. lar. Cephalopelvic proportions are thus low, and there are no obstetric constraints. Pelvic sexual dimorphism is absent. Overall, these data indicate that pelvic sexual dimorphism in hylobatids reflects obstetric constraints. Anat Rec, 300:859–869, 2017. © 2017 Wiley Periodicals, Inc.
Determinants of Iliac Blade Orientation in Anthropoid Primates
Authors: Middleton Emily R. , Winkler Zachariah J. , Hammond Ashley S. , Plavcan J. Michael , Ward Carol V. 
Published: April 2017

ABSTRACTOrientation of the iliac blades is a key feature that appears to distinguish extant apes from monkeys. Iliac morphology is hypothesized to reflect variation in thoracic shape that, in turn, reflects adaptations for shoulder and forearm function in anthropoids. Iliac orientation is traditionally measured relative to the acetabulum, whereas functional explanations pertain to its orientation relative to the cardinal anatomical planes. We investigated iliac orientation relative to a median plane using digital models of hipbones registered to landmark data from articulated pelves. We fit planes to the iliac surfaces, midline, and acetabulum, and investigated linear metrics that characterize geometric relationships of the iliac margins. Our results demonstrate that extant hominoid ilia are not rotated into a coronal plane from a more sagittal position in basal apes and monkeys but that the apparent rotation is the result of geometric changes within the ilia. The whole ilium and its gluteal surface are more coronally oriented in apes, but apes and monkeys do not differ in orientation of the iliac fossa. The angular differences in the whole blade and gluteal surface primarily reflect a narrower iliac tuberosity set closer to the midline in extant apes, reflecting a decrease in erector spinae muscle mass associated with stiffening of the lumbar spine. Mediolateral breadth across the ventral dorsal iliac spines is only slightly greater in extant apes than in monkeys. These results demonstrate that spinal musculature and mobility have a more significant effect on pelvic morphology than does shoulder orientation, as had been previously hypothesized. Anat Rec, 300:810–827, 2017. © 2017 Wiley Periodicals, Inc.
Hominin Hip Biomechanics: Changing Perspectives
Authors: Warrener Anna G. 
Published: April 2017

ABSTRACTThe shape of the human pelvis reflects the unique demands placed on the hip abductor muscles (gluteus medius and gluteus minimus), which stabilize the body in the frontal plane during bipedal locomotion. This morphological shift occurred early in hominin evolution, yet important shape differences between hominin species have led to significant disagreement about abductor function and locomotor capability in these extinct taxa. A static biomechanical model that relies on a close association between skeletal measurements of the pelvis and femur has traditionally been used to reconstruct hip biomechanics in these species. However, experimental biomechanical approaches have highlighted the dynamic nature of mediolateral balance in walking and running, challenging the assumptions of the static hip model. This article reviews traditional approaches for understanding hip abductor function, shows how they have been applied to the fossil hominin record, and discusses new techniques that integrate the dynamic nature of mediolateral balance during human locomotion. Anat Rec, 300:932–945, 2017. © 2017 Wiley Periodicals, Inc.
Evolution of Spinopelvic Alignment in Hominins
Authors: Been Ella , Gómez‐Olivencia Asier , Shefi Sara , Soudack Michalle , Bastir Markus , Barash Alon 
Published: April 2017

ABSTRACTSpinopelvic alignment refers to the interaction between pelvic orientation, spinal curvatures, and the line of gravity. In a healthy modern human, this alignment is characterized by reciprocal curves/orientation of the sacrum, lumbar lordosis, thoracic kyphosis, and cervical lordosis. In an economic sagittal posture, these curvatures keep the line of gravity close to the center of the acetabulum. The purpose of this study is to explore the spinopelvic alignment in extinct hominins. We examined spinopelvic alignment of a single representative from each of the following hominin groups: Australopithecus, Homo erectus (H. erectus), H. neanderthalensis, and early H. sapiens. Pelvic incidence, lumbar lordosis, thoracic kyphosis, and cervical lordosis for each representative was estimated and compared with that of modern humans. Three basic spinopelvic alignments were found: (1) the sinusoidal alignment with moderate to high spinal curvatures and pelvic incidence found in H. erectus and H. sapiens; (2) the straight alignment with small spinal curvatures and small pelvic incidence found in Neandertal lineage hominins; (3) the compound alignment found in Australopithecus, with moderate pelvic incidence and lumbar lordosis, and nearly straight cervical spine. Our results indicate that balanced upright posture can be achieved in different alignments. Each hominin group solved the requirements of erect posture in a slightly different way. Moreover, we propose the term “cranio‐spino‐pelvic balance” to substitute “spino‐pelvic balance.” From an evolutionary perspective, not only changes in the pelvis have conditioned the evolution of the spinal curvatures but also changes in the equilibrium of the head likely also affected this balance. Anat Rec, 300:900–911, 2017. © 2017 Wiley Periodicals, Inc.
Dimorphism in the Size and Shape of the Birth Canal Across Anthropoid Primates
Authors: Moffett Elizabeth A. 
Published: April 2017

ABSTRACTIt has long been noted that the human female birth canal is well adapted to giving birth to large‐brained neonates. However, several species of nonhuman primates give birth to large‐headed neonates compared to the maternal birth canal. The presence of such large cephalopelvic proportions in nonhuman primates presents the question of whether dimorphism in the birth canals of these other species is related to obstetric demand, as such dimorphism is presumed to be in humans. In this study, the hypothesis that either the presence or magnitude of dimorphism in the birth canal is related to large cephalopelvic proportions among anthropoid primates is directly tested. This study shows that birth canal dimorphism is common among anthropoids regardless of cephalopelvic proportions, but taxa with large cephalopelvic proportions have a higher magnitude of dimorphism than those that give birth to relatively small‐headed neonates. Furthermore, humans have exceptionally high levels of dimorphism that cannot be explained based on our large cephalopelvic proportions alone. Anat Rec, 300:870–889, 2017. © 2017 Wiley Periodicals, Inc.
Neonatal Shoulder Width Suggests a Semirotational, Oblique Birth Mechanism in Australopithecus afarensis
Authors: DeSilva Jeremy M. , Laudicina Natalie M. , Rosenberg Karen R. , Trevathan Wenda R. 
Published: April 2017

ABSTRACTBirth mechanics in early hominins are often reconstructed based on cephalopelvic proportions, with little attention paid to neonatal shoulders. Here, we find that neonatal biacromial breadth can be estimated from adult clavicular length (R2 = 0.80) in primates. Using this relationship and clavicular length from adult Australopithecus afarensis, we estimate biacromial breadth in neonatal australopiths. Combined with neonatal head dimensions, we reconstruct birth in A. afarensis (A.L. 288‐1 or Lucy) and find that the most likely mechanism of birth in this early hominin was a semi‐rotational oblique birth in which the head engaged and passed through the inlet transversely, but then rotated so that the head and shoulders remained perpendicular and progressed through the midplane and outlet oblique to the main axis of the female pelvis. Any other mechanism of birth, including asynclitic birth, would have resulted in either the head or the shoulders orthogonal to the short anteroposterior dimension of the A.L. 288‐1 pelvis, making birth untenable. There is a tight fit between the infant and all planes of the birth canal, perhaps suggesting a difficult labor in australopiths. However, the rotational birth mechanism of large‐brained humans today was likely not characteristic of A. afarensis. Thus, the evolution of rotational birth, usually associated with encephalization, may have occurred in two stages: the first appeared with the origin of the australopiths with their platypelloid pelves adapted for bipedalism and their broad‐shouldered neonates; the second which resulted in the modern mechanism of rotational birth may be associated with increasing brain size in the genus Homo. Anat Rec, 300:890–899, 2017. © 2017 Wiley Periodicals, Inc.