bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pseudo‐tetrahedral Rhodium and Iridium Complexes: Catalytic Synthesis of E‐Enynes
Authors: Geer Ana M. , Julián Alejandro , López José A. , Ciriano Miguel A. , Tejel Cristina 
Published: September 2018

AbstractThe reactions of the rhodium(I) and iridium(I) complexes [M(PhBP3)(C2H4)(NCMe)] (PhBP3=PhB(CH2PPh2)3−) with alkynes have resulted in the synthesis of a new family of pseudo‐tetrahedral complexes, [M(PhBP3)(RC≡CR′)] (M=Rh, Ir), which contain the alkyne as a four‐electron donor. The reactions of these unusual compounds with two‐electron donors (L=PMe3, CNtBu) produced a change in the “donicity” of the alkyne from a 4e− to a 2e− donor to give five‐coordinate complexes. These were the final products with the iridium complexes, whereas further reactions took place with the rhodium complexes. In particular, C(sp)−H bond activation of the alkyne occurred leading to hydrido alkynyl complexes. This process is essential for the further reactivity of the alkynes, and if the alkyne itself was used as reagent, E‐enyne complexes were obtained. As a consequence of this chemistry, we show that the complex [Rh(PhBP3)(C2H4)(NCMe)] is a very efficient pre‐catalyst for the regioselective di‐ and trimerization of terminal alkynes to E‐enynes and benzene derivatives, respectively. Interestingly, acetonitrile significantly enhanced the catalytic activity by facilitating the C(sp)−H bond activation step. A hydrometalation mechanism to account for these experimental observations is proposed.
Effect of an equal‐access military health system on racial disparities in colorectal cancer screening
Authors: Changoor Navin R. , Pak Linda M. , Nguyen Louis L. , Bleday Ronald , Trinh Quoc‐Dien , Koehlmoos Tracey , Learn Peter A. , Haider Adil H. , Goldberg Joel E. 
Published: September 2018

BACKGROUNDRacial disparities in colorectal cancer (CRC) screening are frequently attributed to variations in insurance status. The objective of this study was to ascertain whether universal insurance would lead to more equitable utilization of CRC screening for black patients in comparison with white patients.METHODSClaims data from TRICARE (insurance coverage for active, reserve, and retired members of the US Armed Services and their dependents) for 2007‐2010 were queried for adults aged 50 years in 2007, and they were followed forward in time for 4 years (ages, 50‐53 years) to identify their first lower endoscopy and/or fecal occult blood test (FOBT). Variations in CRC screening were compared with descriptive statistics and multivariate logistic regression.RESULTSAmong the 24,944 patients studied, 69.2% were white, 20.3% were black, 4.9% were Asian, and 5.6% were other. Overall, 54.0% received any screening: 83.7% received endoscopy, and 16.3% received FOBT alone. Compared with whites, black patients had higher screening rates (56.5%) and had 20% higher risk‐adjusted odds of being screened (95% confidence interval [CI], 1.11‐1.29). Asian patients had a likelihood of screening similar to that of white patients (odds ratio [OR], 1.06; 95% CI, 0.92‐1.23). Females (OR, 1.20; 95% CI, 1.10‐1.33), active‐duty personnel (OR, 1.15; 95% CI, 1.06‐1.25), and officers (OR, 1.28; 95% CI, 1.18‐1.37) were also more likely to be screened.CONCLUSIONWithin an equal‐access, universal health care system, black patients had higher rates of CRC screening in comparison with prior reports and even in comparison with white patients within the population. These findings highlight the need to understand and develop meaningful approaches for promoting more equitable access to preventative care. Moreover, equal‐access, universal health insurance for both the military and civilian populations can be presumed to improve access for underserved minorities.
Pediatric melanoma in melanoma‐prone families
Authors: Goldstein Alisa M. , Stidd Kelsey C. , Yang Xiaohong R. , Fraser Mary C. , Tucker Margaret A. 
Published: September 2018

BACKGROUNDIn the United States, only approximately 0.4% of all melanomas are diagnosed in patients aged <20 years. To the authors' knowledge, melanoma in pediatric members of melanoma‐prone families has not been fully investigated to date. The objective of the current study was to evaluate pediatric patients with melanoma with extensive follow‐up in melanoma‐prone families with and without cyclin‐dependent kinase inhibitor 2A (CDKN2A) mutations.METHODSFor this non‐population‐based study, families were followed prospectively for up to 40 years. A total of 60 families with ≥ 3 patients with melanoma were included for analysis: 30 CDKN2A mutation‐positive (CDKN2A+) and 30 CDKN2A mutation‐negative (CDKN2A‐) families. Age at the time of first melanoma and number of melanomas were obtained for each patient and summarized by family or sets (CDKN2A + vs CDKN2A‐). For set comparisons and categorical variables (occurrence of melanoma in pediatric patients, number of melanomas, number of patients with single or multiple melanomas), the Pearson chi‐square or Fisher exact test was used.RESULTSRegardless of CDKN2A status, melanoma‐prone families were found to have 6‐fold to 28‐fold higher percentages of patients with pediatric melanoma compared with the general population of patients with melanoma in the United States. Within CDKN2A + families, pediatric patients with melanoma were significantly more likely to have multiple melanomas compared with their relatives who were diagnosed at age >20 years (71% vs 38%, respectively; P = .004). CDKN2A + families had significantly higher percentages of pediatric patients with melanoma compared with CDKN2A‐ families (11.1% vs 2.5%; P = .004).CONCLUSIONSThese observations have implications for the prevention of melanoma as well as clinical care for its early detection. Children in melanoma‐prone families should have careful sun protection from an early age and skin surveillance to reduce their risk of melanoma.
A Novel Assay Format as an Alternative to ELISA: MINA Test for Biotin
Authors: Piletsky Stanislav S. , Cass Anthony E. G. , Piletska Elena V. , Czulak Joanna , Piletsky Sergey A. 
Published: September 2018

AbstractA novel abiotic assay based on biotin‐specific fluorescent molecularly imprinted polymer nanoparticles (nanoMIPs) which acted as both reporter probes and binding agents, was developed. This is a first report of an assay which, unlike ELISA, required no washing steps or addition of enzyme substrates, making it more user‐friendly. The components of the molecularly imprinted polymer nanoparticles assay (MINA) were assembled in microtiter plates fitted with magnetic inserts. The fluorescent nanoMIPs were bound to biotin‐conjugated magnetic particles, which were attracted to the inserts. The addition of free biotin caused a displacement of the fluorescent nanoMIPs into solution, generating a signal proportional to the concentration of biotin. The nanoMIPs had a dissociation constant (Kd) of 14 nM, allowing the assay to detect biotin at nano‐molar concentrations. The pre‐assembled assay only required the addition of the sample and measurement of the fluorescence, and it functioned well after six weeks of storage without refrigeration. The assay did not show the susceptibility to several compounds which are known to interfere with avidin and streptavidin‐based assays, such as mercaptoethanol and sugars. The protocols optimized in this work could be used to develop the abiotic assays for any other compound of interest.
Protocol for Chromatin Immunoprecipitation of Meiotic‐Stage‐Specific Tomato Anthers
Authors: Chouaref Jihed , de Boer Esther , Fransz Paul , Stam Maike 
Published: September 2018

AbstractInteractions occurring between DNA and proteins across the nuclear genome regulate numerous processes, including meiosis. Meiosis ensures genetic variation and balanced segregation of homologous chromosomes. It involves complex DNA‐protein interactions across the entire genome to regulate a broad range of processes, including formation and repair of double‐strand DNA breaks (DSBs), chromosome compaction, homolog pairing, synapsis, and homologous recombination. The latter meiotic event, meiotic recombination, often occurs at discrete locations in a genome, within a tight time window. The identification of genomic binding sites of meiotic proteins is a major step toward understanding the molecular mechanisms underlying meiotic recombination and provides important information for plant breeding. Collecting meiotic cells from plants is challenging, tedious, and time consuming, since the meiocyte‐producing organs, the anthers, are generally small and limited to certain developmental stages of plants. Here we provide a protocol to isolate meiotic‐stage‐specific anthers and perform ChIP on this material. We have developed a ChIP protocol specifically suited to (1) small amounts of input material and (2) proteins that bind transiently to chromatin and at very low frequency. © 2018 by John Wiley & Sons, Inc.
Ordered Mesoporous LiFe5O8 Thin‐Film Photoanodes for Water Splitting
Authors: Waitz Stefanie , Suchomski Christian , Brezesinski Torsten , Marschall Roland 
Published: September 2018

AbstractThe optical and photoelectrochemical properties of ordered mesoporous α‐LiFe5O8 thin films have been investigated. These sol−gel thin films exhibit a complex band structure, indicating a band gap of 2.45 eV, with additional absorption in the visible region up to λ=600 nm. Mott−Schottky plots reveal their applicability as photoanodes for water splitting (as they are n‐type semiconductors) and photoelectrochemical tests show good performance for water oxidation.
Fabrication of a Mo‐Doped Strontium Cobaltite Perovskite Hybrid Supercapacitor Cell with High Energy Density and Excellent Cycling Life
Authors: Tomar Anuj Kumar , Singh Gurmeet , Sharma Raj Kishore 
Published: September 2018

AbstractEnriched with oxygen vacancies, Mo‐doped strontium cobaltite (SrCo0.9Mo0.1O3−δ, SCM) is synthesized as an oxygen anion‐intercalated charge‐storage material through the sol–gel method. The supplemented oxygen vacancies, good electrical conductivity, and high ion diffusion coefficient bestow the SCM electrode with excellent specific capacitance (1223.34 F g−1) and specific capacity (168.88 mAh g−1) at 1 A g−1. The decisive constant (b‐value) deduced for the charge storage mechanism (low scan‐rate region) is nearly 0.8, indicating a highly capacitive process. In the high scan‐rate region, however, the b‐value is almost 0.5, and a linear pattern of charge (q) versus the inverse of the square root of the scan rate (v−1/2) is obtained. The results reveal O2− diffusion as the rate‐limiting factor for charge storage. Furthermore, a hybrid cell (SCM∥LRGONR) is fabricated by using lacey, reduced graphene oxide nanoribbon (LRGONR) as the negative electrode, which exhibits a high energy density (74.8 Wh kg−1 at a power density of 734.5 W kg−1). With a charging time of only 20.7 s, the cell sustains a very high energy density (33 Wh kg−1) with a high power delivery rate (6600 W kg−1). The excellent cycling stability (165.1 % activated specific capacitance retention and 97.6 % of the maximum value attained) after 10 000 charge–discharge cycles, demonstrates SCM is a potential electrode material for supercapacitors.
Incidence and trend of type 1 diabetes and the underlying environmental determinants
Authors: Xia Ying , Xie Zhiguo , Huang Gan , Zhou Zhiguang 
Published: September 2018

SummaryA wealth of epidemiological studies concerning the distribution of type 1 diabetes (T1D) around the world have pointed to the appreciable variation in the incidence of T1D among disparate age groups, ethnicities, and geographical locations. On the whole, the incidence of childhood T1D has been on the rise, and a plausible inverse relationship between the initial incidence rate and the following annual increase in incidence has been raised. Countries that used to exhibit lower incidences tend to have steep annual increase whereas those with already‐established high incidences are more likely to show a modest increase or even stabilization in T1D incidence. Environmental agents considered responsible for the current evolving pattern of T1D incidence will be detailed, mainly including the increasing prevalence of childhood obesity, viral infections in a chronic manner, maternal‐child interaction such as breastfeeding, and latitude‐ultraviolet B‐vitamin D pathway. Certain rationale has been put forward in an attempt to explain the potential association between environmental agents and development of T1D. For instance, accelerator hypothesis regards insulin resistance as the promoter of earlier disease onset in obese children whereas the negative correlation of microbial infections in background populations with incidence of T1D represents the basic component of the hygiene hypothesis. Further investigations are still warranted to verify these theories across multiple ethnic groups and to identify additional contributors to the variation in T1D incidence.
A bioenergetics evaluation of temperature‐dependent selection for the spawning phenology by Snake River fall Chinook salmon
Authors: Plumb John M. 
Published: September 2018

AbstractHigh water temperatures can increase the energetic cost for salmon to migrate and spawn, which can be important for Snake River fall‐run Chinook salmon because they migrate great distances (>500 km) at a time when river temperatures (18–24°C) can be above their optimum temperatures (16.5°C). Average river temperatures and random combinations of migration and spawning dates were used to simulate fish travel times and determine the energetic consequences of different thermal experiences during migration. An energy threshold criterion (4 kJ/g) was also imposed on survival and spawning success, which was used to determine how prevailing temperatures might select against certain migration dates and thermal experiences, and in turn, explain the selection for the current spawning phenology of the population. Scenarios of tributary use for thermal refugia under increasing water temperatures (1, 2, and 3°C) were also run to determine which combinations of migration dates, travel rates, and resulting thermal experiences might be most affected by energy exhaustion. As expected, when compared to observations, the model under existing conditions and energy use could explain the onset, but not the end of the observed spawning migration. Simulations of early migrants had greater energy loss than late migrants regardless of the river temperature scenario, but higher temperatures disproportionately selected against a larger fraction of early‐migrating fish, although using cold‐water tributaries during migration provided a buffer against higher energy use at higher temperatures. The fraction of simulated fish that exceeded the threshold for migration success increased from 58% to 72% as average seasonal river temperatures over baseline temperatures increased. The model supports the conclusion that increases in average seasonal river temperatures as little as 1°C could impose greater thermal constraints on the fish, select against early migrants, and in turn, truncate the onset of the current spawning migration.
Habitat or temporal isolation: Unraveling herbivore–parasitoid speciation patterns using double digest RADseq
Authors: Zhang Y. Miles , Bass Amber I. H. , Fernández D. Catalina , Sharanowski Barbara J. 
Published: September 2018

AbstractEcological speciation is often observed in phytophagous insects and their parasitoids due to divergent selection caused by host‐associated or temporal differences. Most previous studies have utilized limited genetic markers or distantly related species to look for reproductive barriers of speciation. In our study, we focus on closely related species of Lygus bugs and two sister species of Peristenus parasitoid wasps. Using mitochondrial DNA COI and genomewide SNPs generated using ddRADseq, we tested for potential effects of host‐associated differentiation (HAD) or temporal isolation in this system. While three species of Lygus are clearly delineated with both COI and SNPs, no evidence of HAD or temporal differentiation was detected. Two Peristenus sister species were supported by both sets of markers and separated temporally, with P. mellipes emerging early in June and attacking the first generation of Lygus, while P. howardi emerging later in August and attacking the second generation of their hosts. This is one of the few studies to examine closely related hosts and parasitoids to examine drivers of diversification. Given the results of this study, the Lygus‐Peristenus system demonstrates temporal isolation as a potential barrier to reproductive isolation for parasitoids, which could indicate higher parasitoid diversity in regions of multivoltine hosts. This study also demonstrates that incorporating systematics improves studies of parasitoid speciation, particularly by obtaining accurate host records through rearing, carefully delimiting cryptic species and examining population‐level differences with genomic‐scale data among closely related taxa.
The effectiveness of journals as arbiters of scientific impact
Authors: Paine C. E. Timothy , Fox Charles W. 
Published: September 2018

AbstractAcademic publishers purport to be arbiters of knowledge, aiming to publish studies that advance the frontiers of their research domain. Yet the effectiveness of journal editors at identifying novel and important research is generally unknown, in part because of the confidential nature of the editorial and peer review process. Using questionnaires, we evaluated the degree to which journals are effective arbiters of scientific impact on the domain of Ecology, quantified by three key criteria. First, journals discriminated against low‐impact manuscripts: The probability of rejection increased as the number of citations gained by the published paper decreased. Second, journals were more likely to publish high‐impact manuscripts (those that obtained citations in 90th percentile for their journal) than run‐of‐the‐mill manuscripts; editors were only 23% and 41% as likely to reject an eventual high‐impact paper (pre‐ versus postreview rejection) compared to a run‐of‐the‐mill paper. Third, editors did occasionally reject papers that went on to be highly cited. Error rates were low, however: Only 3.8% of rejected papers gained more citations than the median article in the journal that rejected them, and only 9.2% of rejected manuscripts went on to be high‐impact papers in the (generally lower impact factor) publishing journal. The effectiveness of scientific arbitration increased with journal prominence, although some highly prominent journals were no more effective than much less prominent ones. We conclude that the academic publishing system, founded on peer review, appropriately recognizes the significance of research contained in manuscripts, as measured by the number of citations that manuscripts obtain after publication, even though some errors are made. We therefore recommend that authors reduce publication delays by choosing journals appropriate to the significance of their research.
Prevalence and diversity of haemosporidian parasites in the yellow‐rumped warbler hybrid zone
Authors: Cozzarolo Camille‐Sophie , Jenkins Tania , Toews David P. L. , Brelsford Alan , Christe Philippe 
Published: September 2018

AbstractParasites can play a role in speciation, by exerting different selection pressures on different host lineages, leading to reproductive barriers in regions of possible interbreeding. Hybrid zones therefore offer an ideal system to study the effect of parasites on speciation. Here, we study a hybrid zone in the foothills of the Rocky Mountains where two yellow‐rumped warbler subspecies, Setophaga coronata coronata and S. c. auduboni, interbreed. There is partial reproductive isolation between them, but no evidence of strong assortative mating within the hybrid zone, suggesting the existence of a postzygotic selection against hybrids. Here, we test whether haemosporidian parasites might play a role in selecting against hybrids between S. c. coronata and S. c. auduboni. We screened birds from five transects across the hybrid zone for three phylogenetic groupings of avian haemosporidians Plasmodium, Haemoproteus and Leucocytozoon parasites and quantified intensity of infection. Contrary to our prediction, hybrids did not have higher haemosporidian parasite prevalence. Variation in Haemoproteus prevalence was best explained by an interaction between a birds’ hybrid index and elevation, while the probability of infection with Leucocytozoon parasites was only influenced by elevation. We also found no significant difference in the diversity of haemosporidian lineages between the warbler subspecies and their hybrids. Finally, intensity of infection by Haemoproteus increased significantly with elevation, but was not significantly linked to birds’ hybrid index. In conclusion, our data suggest that haemosporidian parasites do not seem to play a major role in selecting against hybrids in this system.
Ontogenetic resource utilization and migration reconstruction with δ13C values of essential amino acids in the Cynoscion acoupa otolith
Authors: Vane Kim , Larsen Thomas , Scholz‐Böttcher Barbara M. , Kopke Bernd , Ekau Werner 
Published: September 2018

AbstractWith the increasing anthropogenic impacts on fish habitats, it has become more important to understand which primary resources sustain fish populations. This resource utilization can differ between fish life stages, and individuals can migrate between habitats in search of resources. Such lifetime information is difficult to obtain due to the large spatial and temporal scales of fish behavior. The otolith organic matrix has the potential to indicate this resource utilization and migration with δ13C values of essential amino acids (EAAs), which are a direct indication of the primary producers. In a proof‐of‐concept study, we selected the Acoupa weakfish, Cynoscion acoupa, as a model fish species with distinct ontogenetic migration patterns. While it inhabits the Brazilian mangrove estuaries during juvenile stages, it moves to the coastal shelf as an adult. Thus, we expected that lifetime resource utilization and migration would be reflected in δ13CEAA patterns and baseline values in C. acoupa otoliths. By analyzing the C. acoupa otolith edges across a size range of 12–119 cm, we found that baseline δ13CEAA values increased with size, which indicated an estuarine to coastal shelf distribution. This trend is highly correlated with inorganic δ13C values. The δ13CEAA patterns showed that estuarine algae rather than mangrove‐derived resources supported the juvenile C. acoupa populations. Around the juvenile size of 40 cm, resource utilization overlapped with those of adults and mean baseline δ13CEAA values increased. This trend was confirmed by comparing otolith core and edges, although with some individuals potentially migrating over longer distances than others. Hence, δ13CEAA patterns and baseline values in otoliths have great potential to reconstruct ontogenetic shifts in resource use and habitats. The insight could aid in predictions on how environmental changes affect fish populations by identifying the controlling factors at the base of the food web.