bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detecting the persistence of drying trends under changing climate conditions using four meteorological drought indices
Authors: Khan Muhammad Imran , Liu Dong , Fu Qiang , Faiz Muhammad Abrar 
Published: November 2017

ABSTRACTNumerous drought indices based on single or multiple variables have been developed for the assessment of drought. This study aimed to detect the variability of droughts by applying four drought indices, the standardized precipitation index, the reconnaissance drought index, the standardized precipitation evaporative drought index and the effective drought index, at five meteorological stations in the Songhua River basin (SRB) in China during 1962–2013 and at two meteorological stations in the Indus River basin (IRB) during 1980–2013 using different timescales (3, 6, 9 and 12 months). Moreover, a Mann−Kendall trend test at the 5% significance level was used for the assessment of drought trends in the basins. The results indicated that the 12 month data series for the SRB and the 6 month data series for the IRB were appropriate for assessing dry conditions and for comparing the drought indices. Pearson's correlation analyses between the drought indices results and the meteorological variables revealed that the standardized precipitation index is a better drought index for the assessment of drought in the SRB (r = 0.99). The results also showed that the standardized precipitation evaporative drought index versus the reconnaissance drought index is better at identifying drought in the IRB with a Pearson's correlation value r of 0.98. Severe and extremely dry conditions prevailed between 1990 and 2001 in the SRB, and there were extreme drought conditions with an intensity of −2.00 in the IRB during 2001–2002. Overall, this study provides insights into choosing the appropriate time interval and drought index for a specific region to identify the severity of droughts.
Generative Recurrent Networks for De Novo Drug Design
Authors: Gupta Anvita , Müller Alex T. , Huisman Berend J. H. , Fuchs Jens A. , Schneider Petra , Schneider Gisbert 
Published: November 2017

AbstractGenerative artificial intelligence models present a fresh approach to chemogenomics and de novo drug design, as they provide researchers with the ability to narrow down their search of the chemical space and focus on regions of interest. We present a method for molecular de novo design that utilizes generative recurrent neural networks (RNN) containing long short‐term memory (LSTM) cells. This computational model captured the syntax of molecular representation in terms of SMILES strings with close to perfect accuracy. The learned pattern probabilities can be used for de novo SMILES generation. This molecular design concept eliminates the need for virtual compound library enumeration. By employing transfer learning, we fine‐tuned the RNN′s predictions for specific molecular targets. This approach enables virtual compound design without requiring secondary or external activity prediction, which could introduce error or unwanted bias. The results obtained advocate this generative RNN‐LSTM system for high‐impact use cases, such as low‐data drug discovery, fragment based molecular design, and hit‐to‐lead optimization for diverse drug targets.
Dynamic collimator trajectory algorithm for multiple metastases dynamic conformal arc treatment planning
Authors: MacDonald R. Lee , Thomas Christopher G. , Syme Alasdair 
Published: November 2017

PurposeTo develop an algorithm for dynamic collimator positioning to optimize beam's eye view (BEV) fitting of targets in dynamic conformal arc (DCA)‐based radiotherapy procedures, of particular use in multiple metastases stereotactic radiosurgery procedures.MethodsA trajectory algorithm was developed to dynamically modify the angle of the collimator as a function of arc‐based control point to provide optimized collimation of target volume(s). Central to this algorithm is a concept denoted herein as “whitespace” defined as any nontarget area in the BEV that is not covered by any collimation system and is open to exposure from the radiation beam. Calculating whitespace at all collimator angles and every control point, a two‐dimensional topographical map depicting the tightness‐of‐fit of the MLC was generated. A bidirectional gradient trajectory algorithm identified a number of candidate trajectories of continuous collimator motion. Minimization of integrated whitespace was used to identify an optimal solution for the navigation of the parameter space. Plans with dynamic collimator trajectories were designed for multiple metastases targets and were compared with fixed collimator angle dynamic conformal arc (DCA) plans and standard VMAT plans.ResultsAlgorithm validation was performed on simple test cases with known solutions. The whitespace metric showed a strong correlation (R2 = 0.90) with mean dose to proximal normal tissue. Seventeen cases were studied using our algorithm to generate dynamic conformal arc (DCA) plans with optimized collimator trajectories for three and four target SRS patients and comparing them to DCA plans generated with optimized fixed collimator angles per arc and standard VMAT plans generated via template. Optimized collimator trajectories were found to produce a reduction in monitor units of up to 49.7 ± 5.1% when compared to VMAT across 17 patients, and all organ‐at‐risk and normal brain metrics were found to be superior or comparable.ConclusionDynamic collimator trajectories have the potential to improve DCA deliveries through increased efficiency, especially in the treatment of multiple cranial metastases. Implementation of this technology should not be hindered by mechanical safety considerations as collimator motions do not modify or introduce any new risks of collisions with patients.
Comparison of ferumoxytol‐based cerebral blood volume estimates using quantitative R1 and relaxometry
Authors: Rivera‐Rivera Leonardo A. , Schubert Tilman , Knobloch Gesine , Turski Patrick A. , Wieben Oliver , Reeder Scott B. , Johnson Kevin M. 
Published: November 2017

PurposeCerebral perfusion is commonly assessed clinically with dynamic susceptibility contrast MRI using a bolus injection of gadolinium‐based contrast agents, resulting in semi‐quantitative values of cerebral blood volume (CBV). Steady‐state imaging with ferumoxytol allows estimation of CBV with the potential for higher precision and accuracy. Prior CBV studies have focused on the signal disrupting
effects, but ferumoxytol also has high signal‐enhancing T1 relaxivity. The purpose of this study was to investigate and compare CBV estimation using T1 and
, with the goal of understanding the contrast mechanisms and quantitative differences.MethodsChanges in R1 (1/T1) and
(1/
) were measured after the administration of ferumoxytol using high‐resolution quantitative approaches. Images were acquired at 3.0T and R1 was estimated from an ultrashort echo time variable flip angle approach, while
was estimated from a multiple gradient echo sequence. Twenty healthy volunteers were imaged at two doses. CBV was derived and compared from relaxometry in gray and white matter using different approaches.ResultsR1 measurements showed a linear dependence of blood R1 with respect to dose in large vessels, in contrast to the nonlinear dose‐dependence of blood
estimates. In the brain parenchyma,
showed linear dose‐dependency whereas R1 showed nonlinearity. CBV calculations based on
changes in tissue and ferumoxytol blood concentration estimates based on R1 relaxivity showed the lowest variability in our cohort.ConclusionsCBV measurements were successfully derived using a combined approach of R1 and
relaxometry. Magn Reson Med 79:3072–3081, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Daumenkino der Moleküle
Authors: Hayes Stuart A. , Epp Sascha W. , Miller R. J. Dwayne 
Published: November 2017

ZusammenfassungBewegungen auf atomarer Ebene und molekulare Strukturveränderungen sind Grundphänomene in Chemie und Physik. Schon lange träumt die Wissenschaft davon, diese Prozesse auf den fundamentalen Längen‐ und Zeitskalen direkt zu beobachten. Solche „Molekülfilme“ werden durch Methoden möglich, bei denen ein kurzer Laser‐Pumppuls eine Reaktion startet und nach einer gewissen Verzögerung ein zweiter kurzer Probepuls ihren momentanen Zustand festhält. Für atomare Auflösung benötigt der Probepuls sehr kurze Wellenlängen, etwa Röntgenstrahlung oder Elektronen. Unsere Methode nutzt ultraschnelle Elektronenbeugung mit dem Vorteil relativ kompakter Experimente im Vergleich zu Freie‐Elektronen‐Lasern für Röntgenstrahlung. Damit gelingen uns erste Molekülfilme, die den Ablauf von Reaktionen im atomaren Detail zeigen. Sie geben Einblick in die Auswahlmechanismen, nach denen chemische Reaktionen einen bestimmten Reaktionspfad unter vielen Pfaden wählen.
Fein und schnell
Authors: Kloth Philipp , Wenderoth Martin 
Published: November 2017

ZusammenfassungDie Verbindung von atomar auflösenden Techniken wie Rastertunnelmikroskopie mit optischen Pump‐Probe‐Methoden bietet neue Möglichkeiten, dynamische mikroskopische Prozesse zu erforschen. Unsere Untersuchungen der photogenerierten Ladungsdynamik an einer Galliumarsenid‐Oberfläche zeigen beispielhaft, wie bedeutend solche Charakterisierungen für eine weitere Miniaturisierung in der Mikroelektronik sein können. Das Forschungsfeld befindet sich aber erst im Anfangsstadium, neben optischen werden auch elektronische Pump‐Probe‐Methoden getestet. Es wird sicherlich noch einige Jahre dauern, bis diese Techniken reif für eine breitere Anwendung sind.
Brownian dynamic study of an enzyme metabolon in the TCA cycle: Substrate kinetics and channeling
Authors: Huang Yu‐ming M. , Huber Gary A. , Wang Nuo , Minteer Shelley D. , McCammon J. Andrew 
Published: November 2017

AbstractMalate dehydrogenase (MDH) and citrate synthase (CS) are two pacemaking enzymes involved in the tricarboxylic acid (TCA) cycle. Oxaloacetate (OAA) molecules are the intermediate substrates that are transferred from the MDH to CS to carry out sequential catalysis. It is known that, to achieve a high flux of intermediate transport and reduce the probability of substrate leaking, a MDH‐CS metabolon forms to enhance the OAA substrate channeling. In this study, we aim to understand the OAA channeling within possible MDH‐CS metabolons that have different structural orientations in their complexes. Three MDH‐CS metabolons from native bovine, wild‐type porcine, and recombinant sources, published in recent work, were selected to calculate OAA transfer efficiency by Brownian dynamics (BD) simulations and to study, through electrostatic potential calculations, a possible role of charges that drive the substrate channeling. Our results show that an electrostatic channel is formed in the metabolons of native bovine and recombinant porcine enzymes, which guides the oppositely charged OAA molecules passing through the channel and enhances the transfer efficiency. However, the channeling probability in a suggested wild‐type porcine metabolon conformation is reduced due to an extended diffusion length between the MDH and CS active sites, implying that the corresponding arrangements of MDH and CS result in the decrease of electrostatic steering between substrates and protein surface and then reduce the substrate transfer efficiency from one active site to another.
Trajectories of ethnic neighbourhood change: Spatial patterns of increasing ethnic diversity
Authors: Zwiers Merle , van Ham Maarten , Manley David 
Published: November 2017

AbstractWestern cities are increasingly ethnically diverse, and in most cities, the share of the population belonging to an ethnic minority is growing. Studies analysing changing ethnic geographies often limit their analysis to changes in ethnic concentrations in neighbourhoods between 2 points in time. Such a temporally limited approach limits our understanding of pathways of ethnic neighbourhood change and of the underlying factors contributing to change. This paper analyses full trajectories of neighbourhood change in the 4 largest cities in the Netherlands between 1999 and 2013. Our modelling strategy categorises neighbourhoods based on their unique growth trajectories of the ethnic population composition, providing insight in processes of ethnic segregation and its drivers. Our main conclusion is that the ethnic composition in neighbourhoods remains relatively stable over time. We however find evidence for a slow trend towards deconcentration of ethnic minorities and increased population mixing in most neighbourhoods. Spatial mixing appears to be driven by the selective mobility patterns of the native Dutch population as a result of urban restructuring programmes. However, these pathways towards deconcentration are mitigated by processes of ethnic natural growth that reinforce existing patterns of segregation. Despite an increasing inflow of the native Dutch into ethnic concentration neighbourhoods, segregation at the top and bottom ends of the distribution seems to be persistent: High concentrations of ethnic minorities in disadvantaged neighbourhoods versus high concentrations of the native population in more affluent neighbourhoods continue to be a feature of Dutch cities.
The potential for Assemblage thinking in population geography: Assembling population, space, and place
Authors: Duffy Paula , Stojanovic Tim 
Published: November 2017

AbstractThis study explores “Assemblage” thinking as an approach to population geography research. The paper highlights the recent prominence of Assemblage thinking in human geography, before exploring the potential opportunities for engagement by population geographers. In particular, we focus on the production of place as co‐constituted by the material (space) and the discursive (knowledge, process, and practice). Considering the Assemblage practice of “Rendering Technical,” we reflect on the role that population geography plays in authorising knowledge and supporting policy. This is investigated through a critical taxonomic analysis of recent Scottish demographic data. It is argued on the one hand that this captures key economic and population characteristics of “place,” while on the other hand, it offers a limited technical knowledge. We conclude that a reflexive approach to research using Assemblage thinking may challenge the intimate relationship between population geographers and the state.
Probability of Alzheimer's disease in breast cancer survivors based on gray‐matter structural network efficiency
Authors: Kesler Shelli R. , Rao Vikram , Ray William J. , Rao Arvind ,   Alzheimer's Disease Neuroimaging Initiative
Published: November 2017

AbstractIntroductionBreast cancer chemotherapy is associated with accelerated aging and potentially increased risk for Alzheimer's disease (AD).MethodsWe calculated the probability of AD diagnosis from brain network and demographic and genetic data obtained from 47 female AD converters and 47 matched healthy controls. We then applied this algorithm to data from 78 breast cancer survivors.ResultsThe classifier discriminated between AD and healthy controls with 86% accuracy (P < .0001). Chemotherapy‐treated breast cancer survivors demonstrated significantly higher probability of AD compared to healthy controls (P < .0001) and chemotherapy‐naïve survivors (P = .007), even after stratifying for apolipoprotein e4 genotype. Chemotherapy‐naïve survivors also showed higher AD probability compared to healthy controls (P = .014).DiscussionChemotherapy‐treated breast cancer survivors who have a particular profile of brain structure may have a higher risk for AD, especially those who are older and have lower cognitive reserve.
Square Pegs and Round Holes: The Free Movement of Persons Under EEA Law
Authors: FRANKLIN Christian NK 
Published: November 2017

AbstractWhilst the European Union’s aim of achieving an ‘ever closer Union’ is not an objective of EEA cooperation, homogeneity demands that we follow the same path: as the Union gets ever closer, so too does EEA cooperation, in light of the demands of the fundamental principle of homogeneity. This is particularly well demonstrated by looking at developments in the field of the free movement of persons. The case law of the Court of Justice of the European Free Trade Association (EFTA Court) in this field shows that in situations where homogeneity is put to the test, there seems little to suggest that a more national sovereignty-friendly approach has been adopted than under EU law. Notwithstanding the integral differences between the EU and EEA legal constructs, the EFTA Court has proven highly adept at keeping pace with EU developments in the field through a number of bold and creative interpretations of EEA law, and by using different tools to arrive at uniform conclusions.
The Duty of Mind: Ethical Capacity in a Time of Crisis
Authors: Ryus Caitlin , Baruch Jay 
Published: November 2017

AbstractIn a disaster, physicians are forced to make challenging and heartbreaking ethical decisions under conditions of physical and emotional exhaustion. Evidence shows that the conditions of stress that mark disasters can undermine the process of ethical decision-making. This results in biased allocation of scarce resources, fewer utilitarian and altruistic decisions, and a wider variation in decisions. Stress also predisposes clinicians to decision strategy errors, such as premature closure, that lead to poor outcomes. The very ability to make sound and ethical decisions is thus a scarce resource. Ethical frameworks underpinning disaster protocols enumerate many physician obligations, but seldom articulate the risk posed by having decisions made ad hoc by decision-makers who are compromised by the stress of the concurrent crisis. We propose, therefore, that a “duty of mind”—the obligation to make critical decisions under the clearest possible state of thought—be added to ethical frameworks for disaster response. Adding the duty of mind to the pillars on which planning is based would force attention to a moral imperative to include decision support tools in disaster planning. By moving the consideration of possible choices to a moment when time and consultation facilitate clear and considered thought, the duty of mind is upheld. (Disaster Med Public Health Preparedness. 2018;12:657–662)
Centreline and cross-glacier air temperature variability on an Alpine glacier: assessing temperature distribution methods and their influence on melt model calculations
Authors: SHAW THOMAS E. , BROCK BEN W. , AYALA ÁLVARO , RUTTER NICK , PELLICCIOTTI FRANCESCA 
Published: November 2017

ABSTRACTThe spatio-temporal distribution of air temperature over mountain glaciers can demonstrate complex patterns, yet it is often represented simplistically using linear vertical temperature gradients (VTGs) extrapolated from off-glacier locations. We analyse a network of centreline and lateral air temperature observations at Tsanteleina Glacier, Italy, during summer 2015. On average, VTGs are steep (<−0.0065 °C m−1), but they are shallow under warm ambient conditions when the correlation between air temperature and elevation becomes weaker. Published along-flowline temperature distribution methods explain centreline observations well, including warming on the lower glacier tongue, but cannot estimate lateral temperature variability. Application of temperature distribution methods improves simulation of melt rates (RMSE) in an energy-balance model by up to 36% compared to the environmental lapse rate extrapolated from an off-glacier station. However, results suggest that model parameters are not easily transferable to glaciers with a small fetch without recalibration. Such methods have potential to improve estimates of temperature across a glacier, but their parameter transferability should be further linked to the glacier and atmospheric characteristics. Furthermore, ‘cold spots’, which can be >2°C cooler than expected for their elevation, whose occurrence is not predicted by the temperature distribution models, are identified at one-quarter of the measurement sites.
ON THE COMPLEMENT OF THE ZERO-DIVISOR GRAPH OF A PARTIALLY ORDERED SET
Authors: DEVHARE SARIKA , JOSHI VINAYAK , LAGRANGE JOHN 
Published: November 2017

In this paper, it is proved that the complement of the zero-divisor graph of a partially ordered set is weakly perfect if it has finite clique number, completely answering the question raised by Joshi and Khiste [‘Complement of the zero divisor graph of a lattice’,Bull. Aust. Math. Soc. 89(2014), 177–190]. As a consequence, the intersection graph of an intersection-closed family of nonempty subsets of a set is weakly perfect if it has finite clique number. These results are applied to annihilating-ideal graphs and intersection graphs of submodules.
THE ROMAN KINGS IN OROSIUS’HISTORIAE ADVERSVM PAGANOS
Authors: Gassman Mattias 
Published: November 2017

We are ruled by judges whom we know, we enjoy the benefits | Of peace and war, as if the warrior Quirinus, | As if peaceful Numa were governing (Claud.IV Cons. Hon.491–3).With these words the poet Claudian lauds the Emperor Honorius on the occasion of his fourth consulship in 398 by comparing him to Rome's deified founder, Romulus-Quirinus, and to Numa Pompilius, its second king, who was proverbial for wisdom and piety. Claudian's panegyric stands in a long literary tradition in which the legendary Roman kings were depicted as models of statesmanship. This exemplary tradition left its mark on a broad array of late antique works, including historical compendia such as the pseudo-AurelianDe uiris illustribus, which narrates the kings’ deeds as soldiers and statesmen, and the writings of antiquarians such as Macrobius and Servius, who collected information on the kings’ invention of cults and calendars. Servius’ interest in the kings implies that they featured in the teaching provided by other late antiquegrammaticias well, and thus that most literate Latin-speakers would have had some knowledge of their deeds. Advanced education in rhetoric likewise drew on Virgil and other school texts for historicalexemplaincluding Romulus and Numa, who appear in panegyrics and in brief histories, such as Eutropius’Breviary, that probably served as reference texts for the political elite. The kings thus loomed large in Roman perceptions of the founding of their empire, which began with the heroic Romulus, was strengthened by Numa's establishment of the Roman cultic system, and was secured by the later kings’ political and military successes.