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Scikit-learn is a Python module integrating a wide range of state-of-the-art machine learning algorithms for medium-scale supervised and unsupervised problems. This package focuses on bringing machine learning to non-specialists using a general-purpose high-level language. Emphasis is put on ease of use, performance, documentation, and API consistency. It has minimal dependencies and is distributed under the simplified BSD license, encouraging its use in both academic and commercial settings. Source code, binaries, and documentation can be downloaded from http://scikit-learn.org.

This paper presents a new approach to estimation and inference in panel data models with a general multifactor error structure. The unobserved factors and the individual-specific errors are allowed to follow arbitrary stationary processes, and the number of unobserved factors need not be estimated. The basic idea is to filter the individual-specific regressors by means of cross-section averages such that asymptotically as the cross-section dimension (N) tends to infinity, the differential effects of unobserved common factors are eliminated. The estimation procedure has the advantage that it can be computed by least squares applied to auxiliary regressions where the observed regressors are augmented with cross-sectional averages of the dependent variable and the individual-specific regressors. A number of estimators (referred to as common correlated effects (CCE) estimators) are proposed and their asymptotic distributions are derived. The small sample properties of mean group and pooled CCE estimators are investigated by Monte Carlo experiments, showing that the CCE estimators have satisfactory small sample properties even under a substantial degree of heterogeneity and dynamics, and for relatively small values of N and T.

Abstract Iterative inversion methods have been unsuccessful at inverting seismic data obtained from complicated earth models (e.g. the Marmousi model), the primary difficulty being the presence of numerous local minima in the objective function. The presence of local minima at all scales in the seismic inversion problem prevent iterative methods of inversion from attaining a reasonable degree of convergence to the neighborhood of the global minimum. The multigrid method is a technique that improves the performance of iterative inversion by decomposing the problem by scale. At long scales there are fewer local minima and those that remain are further apart from each other. Thus, at long scales iterative methods can get closer to the neighborhood of the global minimum. We apply the multigrid method to a subsampled, low-frequency version of the Marmousi data set. Although issues of source estimation, source bandwidth, and noise are not treated, results show that iterative inversion methods perform much better when employed with a decomposition by scale. Furthermore, the method greatly reduces the computational burden of the inversion that will be of importance for 3-D extensions to the method.

ABSTRACT Sequence stratigraphic concepts suggest that stratal geometries develop and are largely controlled by changes in relative sea level. On the shelf, lowstand deposits, which form during falls and subsequent stillstands of relative sea level, can be recognized by the presence of an unconformity at the base, the isolated and basinward position relative to the previous shoreline, and the abrupt seaward translation of shallow-water and shoreline facies into the basin across an unconformity surface. This seaward translation of facies and shoreline regression in response to relative sea level lowering is termed a “forced regression.” A forced regression is independent of variations of sediment flux and is in contrast with “normal” regressions that occur in response to excess sediment flux relative to space available on the shelf (i.e., accommodation). Forced regressions commonly are associated with a zone of sedimentary bypass, subaerial exposure, and possible fluvial erosion between the newly formed and preceding shorelines. Certain shelf sands, previously interpreted as offshore or mid-shelf sand bodies, thus can be reinterpreted as stranded lowstand shorelines associated with forced regressions. This alternative interpretation has economic significance insofar as it suggests different subsurface correlations and reservoir geometries with the potential for development of new play types and enhanced recovery in older fields. Examples of forced regression can be observed at a variety of scales and ages. Several such examples include the modern East Coulee fan delta and the Lower Cretaceous Viking Formation in Alberta, Canada, the Quaternary Rhône Delta, and the Quaternary Hudson Valley system.

We review synthetic, mechanistic and process aspects of the direct syngas conversion into higher alcohols to foster the identification of industrially-viable catalysts.

Molecular modeling is applied to a representative array of kerogens for the purpose of obtaining quantitative predictions of thermodynamic properties from quantum mechanics and volumetric properties from molecular dynamics. The kerogen model units (175–260 carbon atoms) have been built in the MedeA environment from the sole consideration of the elemental analysis and functional group analysis documented in the work of Exxon and IFP-EN scientists [Kelemen, S. R., et al., Energy Fuels, 2007, 21 (3), pp 1548–1561]. The density results are in good agreement with the well-documented trends of kerogen density with thermal maturity and organic type. The heat capacity in the ideal gas state is predicted to increase as a function of temperature, as obtained from quantum mechanics at the semiempirical level (MOPAC-PM7). This result is in quantitative agreement with experimental heat capacity data on type I kerogen and on coal. This behavior appears clearly as a nonclassical feature, because of the quantization of energy levels in molecular vibrations. Also, the residual heat capacity estimated from molecular dynamics appears subordinate, compared with the ideal heat capacity evaluated from quantum mechanics. The change from negative to positive standard enthalpy of formation when changing from low-maturity kerogen to high-maturity kerogen is also predicted in agreement with correlative methods based on numerous experimental data from coals and fossil fuels. Kerogen model units are available for download free of charge in .xyz or .sci formats from www.materialsdesign.com/science/structures/kerogens_and_coals.

Abstract The Gironde estuary was formed by the Holocene drowning of a fluvial valley incised during the Wurm global sea-level fall. A depositional sequence accumulated in the valley during the eustatic lowstand, the Holocene rise, and the post-Holocene highstand. The sequence comprises a diverse assemblage of lithofacies that can be grouped into lowstand, transgressive, and highstand systems tracts. The lowstand systems tract comprises a continuous unit of relatively thin fluvial gravel and coarse sand in the thalweg of the incised valley. The transgressive systems tract comprises the bulk of the incised valley fill and forms a landward-thinning wedge of tidal-estuarine sands and muds. In the estuary mouth these are overlain by a thick unit of coarse-grained, estuary-mouth tidal-inlet and tidal-delta sands. The highstand systems tract, initiated at about 4000 BP, forms a seaward-prograding, tide-dominated estuarine bayhead delta that has been gradually filling the estuary since the post-Holocene stillstand. Coeval with this filling of the estuary, the adjacent oceanic shoreline has been starved of sediment and is being eroded by waves, indicating that transgressive and highstand systems tracts locally can be synchronous. Several important stratigraphic surfaces punctuate the valley fill: the sequence boundary, the transgressive surface, the tidal ravinement surface, the wave ravinement surface, and the maximum flooding surface. The stratigraphic expression of the sequence boundary depends on its position within the valley. In the thalweg it separates lowstand fluvial deposits from underlying Tertiary carbonates; on the valley walls it is directly overlain by transgressive estuarine sediments. On the interfluves the unconformity continues to be enhanced by modern subaerial erosion. As the interfluves are progressively transgressed by the eroding shoreline, the sequence boundary is expressed as a wave ravinement surface with transgressive marine sediments unconformably overlying Pleistocene or Tertiary substrates. The stratigraphic expression of the transgressive surface in the valley thalweg is characterized by onlap of transgressive tidal-estuarine sediments onto lowstand fluvial deposits. On the valley walls the transgressive surface merges with the sequence boundary. Tidal scour at the estuary mouth forms a deeply erosional tidal ravinement surface overlain by thick estuary-mouth wave- and tide-reworked sands. Subsequently these tidal-inlet sands are eroded by waves associated with the passage of the transgressing shoreline to produce a wave ravinement surface. In the distal part of the estuary the maximum flooding surface is expressed as a downlap surface where the regressive highstand estuarine muds prograde over transgressive tidal-estuarine muddy sands or estuary-mouth sands. In the upstream or proximal end of the estuary the maximum flooding surface separates identical facies, i.e., transgressive and regressive tidal-estuarine point bars, and would be very difficult to identify.

The accurate evaluation of cardiovascular reactions to psychological challenge requires stable baselines against which change can be evaluated. When more than one challenge is employed, the recovery of this baseline becomes important in order to avoid carryover effects. Resting periods, even those of 20 min or more, do not guarantee baseline stability. We compared a 20-min resting condition and a new form of baseline condition in 48 college men using video tasks as the psychological challenges. The new form was a minimally demanding color detection task, termed the "vanilla" baseline condition. A 10-min version and a 20-min version of this condition were tested. Comparisons to 10-min resting baselines were made using our prior work and values from the literature. Vanilla baseline conditions were shown to be equal to or better than resting baseline conditions using criteria of between- and within-baseline stability, amplitude and significance of responsivity, and generalizability between sessions on separate days. Ten-minute resting baselines also showed acceptable stability, questioning the value of lengthy baselines. The good performance of the 10-min vanilla baseline in initial and replication samples supported its utility for estimating baselines for many purposes.

Abstract It is increasingly apparent that faults are typically not discrete planes but zones of deformed rock with a complex internal structure and three-dimensional geometry. In the last decade this has led to renewed interest in the consequences of this complexity for modelling the impact of fault zones on fluid flow and mechanical behaviour of the Earth's crust. A number of processes operate during the development of fault zones, both internally and in the surrounding host rock, which may encourage or inhibit continuing fault zone growth. The complexity of the evolution of a faulted system requires changes in the rheological properties of both the fault zone and the surrounding host rock volume, both of which impact on how the fault zone evolves with increasing displacement. Models of the permeability structure of fault zones emphasize the presence of two types of fault rock components: fractured conduits parallel to the fault and granular core zone barriers to flow. New data presented in this paper on porosity–permeability relationships of fault rocks during laboratory deformation tests support recently advancing concepts which have extended these models to show that poro-mechanical approaches (e.g., critical state soil mechanics, fracture dilatancy) may be applied to predict the fluid flow behaviour of complex fault zones during the active life of the fault. Predicting the three-dimensional heterogeneity of fault zone internal structure is important in the hydrocarbon industry for evaluating the retention capacity of faults in exploration contexts and the hydraulic behaviour in production contexts. Across-fault reservoir juxtaposition or non-juxtaposition, a key property in predicting retention or across-fault leakage, is strongly controlled by the three-dimensional complexity of the fault zone. Although algorithms such as shale gouge ratio greatly help predict capillary threshold pressures, quantification of the statistical variation in fault zone composition will allow estimations of uncertainty in fault retention capacity and hence prospect reserve estimations. Permeability structure in the fault zone is an important issue because bulk fluid flow rates through or along a fault zone are dependent on permeability variations, anisotropy and tortuosity of flow paths. A possible way forward is to compare numerical flow models using statistical variations of permeability in a complex fault zone in a given sandstone/shale context with field-scale estimates of fault zone permeability. Fault zone internal structure is equally important in understanding the seismogenic behaviour of faults. Both geometric and compositional complexities can control the nucleation, propagation and arrest of earthquakes. The presence and complex distribution of different fault zone materials of contrasting velocity-weakening and velocity-strengthening properties is an important factor in controlling earthquake nucleation and whether a fault slips seismogenically or creeps steadily, as illustrated by recent studies of the San Andreas Fault. A synthesis of laboratory experiments presented in this paper shows that fault zone materials which become stronger with increasing slip rate, typically then get weaker as slip rate continues to increase to seismogenic slip rates. Thus the probability that a nucleating rupture can propagate sufficiently to generate a large earthquake depends upon its success in propagating fast enough through these materials in order to give them the required velocity kick. This propagation success is hence controlled by the relative and absolute size distributions of velocity-weakening and velocity-strengthening rocks within the fault zone. Statistical characterisation of the distribution of such contrasting properties within complex fault zones may allow for better predictive models of rupture propagation in the future and provide an additional approach to earthquake size forecasting and early warnings.

STUDY DESIGN: Prospective cohort study. OBJECTIVES: To measure changes in muscle strength, range of motion, and function from 2 weeks before to 6 months after total knee arthroplasty (TKA) and compare outcomes with data from a control group consisting of healthy adults. BACKGROUND: Total knee arthroplasty successfully alleviates pain from knee osteoarthritis, but deficits in function can persist long term. How impairments and functional limitations change over the first 6 months after TKA, compared to data from healthy adults, has not been well reported in the literature. METHODS: Twenty-four patients who underwent a primary unilateral TKA were compared to healthy adults (n = 17). All patients participated in a standardized rehabilitation program following surgery. Isometric quadriceps torque was assessed using an electromechanical dynamometer. Range of motion was measured actively and passively. Functional performance was assessed using the stair-climbing test, timed up-and-go test, 6-minute walk test, and single-limb stance time. Patients underwent testing at 2 weeks preoperatively and at 1, 3, and 6 months postoperatively. RESULTS: Compared to healthy older adults, patients performed significantly worse at all times for all measures (P<.05), except for single-limb stance time at 6 months (P>.05). One month postoperatively, patients experienced significant losses from preoperative levels in all outcomes. Patients recovered to preoperative levels by 6 months postoperatively on all measures, except knee flexion range of motion, but still exhibited the same extent of limitation they did prior to surgery. CONCLUSION: The persistent impairments and functional limitations 6 months after TKA with standard rehabilitation suggest that more intensive therapeutic approaches may be necessary to restore function of patients following TKA to the levels of healthy adults.

ABSTRACT We investigate whether analyst behavior influenced banks' likelihood of winning underwriting mandates for a sample of 16,625 U.S. debt and equity offerings in 1993–2002. We control for the strength of the issuer's investment banking relationships with potential competitors for the mandate, prior lending relationships, and the endogeneity of analyst behavior and the bank's decision to provide analyst coverage. Although analyst behavior was influenced by economic incentives, we find no evidence that aggressive analyst behavior increased their bank's probability of winning an underwriting mandate. The main determinant of the lead‐bank choice is the strength of prior underwriting and lending relationships.

The ilioinguinal approach was developed in 1965 as an anterior approach to the pelvis and acetabulum. Before this date, the Smith-Petersen incision or a modification of it called the iliofemoral approach provided the only access to the upper part of the anterior column of the acetabulum. In the current study of 195 acetabular fractures, the ilioinguinal approach was used alone in 178 cases (90%) and in combination with the Kocker-Langenbeck as a double incision in 17 cases (10%). There were 39 simple and 156 complex associated fracture patterns. There were two large groups of associated fractures: anterior column posterior hemitransverse (39 fractures) and both column fractures (98 cases). Of these fracture patterns stabilized through the ilioinguinal approach, there was a rate of perfect reduction of 85% and 73%, respectively. Of 70 fractures involving the anterior column, anterior wall, and anterior column posterior hemitransverse, there were 61 perfect reductions (87%). The complication rate was extremely low, without any evidence of external iliac fossa heterotopic ossification. The ilioinguinal approach provides total and complete access to the anterior column from the sacroiliac joint to the pubic symphysis. An experienced acetabular surgeon may achieve excellent results even with complex fracture patterns.

ABSTRACT Private equity funds pay particular attention to capital structure when executing leveraged buyouts, creating an interesting setting for examining capital structure theories. Using a large, international sample of buyouts from 1980 to 2008, we find that buyout leverage is unrelated to the cross‐sectional factors, suggested by traditional capital structure theories, that drive public firm leverage. Instead, variation in economy‐wide credit conditions is the main determinant of leverage in buyouts. Higher deal leverage is associated with higher transaction prices and lower buyout fund returns, suggesting that acquirers overpay when access to credit is easier.

Multinational enterprises are often accused of having a preference for investing in countries in which the working populations' civil and political rights are largely disregarded. This article presents an empirical investigation of the popular “political repression boosts FDI” hypothesis and arrives at the conclusion that the hypothesis is not supported. On the contrary, multinational enterprises rather appear to be attracted by countries in which civil and political freedom is respected.

Abstract This article assesses convergence in output per head across regions in the European Community, for the period 1975–90. We use three alternative methodologies to measure convergence, which yield consistent results. We observe that there are strong differences in the pattern of convergence across sub‐periods and across subsets of regions. If the south of Europe seems to catch up in the early 1980s, it stagnates, at best, in the second part of the eighties. At the opposite end, the regions in the north of Europe tend to stagnate or diverge in the first part of the eighties but converge strongly thereafter. This pattern is consistent with the view that northern European countries have adjusted better to the main change in policy regime which occurred in the mid‐1980s, namely the implementation of the internal market programme and the entry of the Iberian peninsula in the Community in 1985. This evidence also lends support to the view that trade liberalization can exacerbate disparities. Finally, our evidence indicates that the distinction between the north and the south of the EC is likely to be more relevant in the analysis of growth patterns than the distinction between the centre and the periphery. Preliminary evidence on migration indicates that the population of the southern regions responds much more slowly to wage and unemployment differences. This may explain partly why southern regions have not converged after 1985.

This work establishes estimates of mass accumulation rates in 18 mostly offshore sedimentary basins in Asia since the beginning of the Cenozoic, ≈ 66 Ma. The estimates were derived from isopach maps, cross-sections and drill holes or stratigraphic columns assuming regional similarity of the strata. Average solid phase volumes and accumulation rates were calculated for nine epochs approximately corresponding to geological periods: Palaeocene (≈ 66–58 Ma), Eocene (≈ 58–37 Ma), Oligocene(≈ 37–30 and 30–24 Ma), Miocene (≈ 24–17, 17–11 and 11–5 Ma), Pliocene (≈ 5–2 Ma) and Quaternary (≈ 2–0 Ma). These rates shed new light on the geological history of Asia since the onset of the collision of India with Asia (≈ 50 Ma). The overall average accumulation rates curve for Asian sedimentary basins since the beginning of the Tertiary shows an exponential form with slow accumulation rates (less than 0.5 × 106km3Myr− 1) until the beginning of the Oligocene, more than 15 Myr after the onset of the collision. From the Oligocene onwards rates increase quickly in an exponential manner, reaching their maximum values in the Quaternary (more than 1.5 × 106km3Myr− 1). From these observations we suggest that extrusion and crustal shortening are complementary processes that have been successively dominant throughout the India–Eurasia collision history. At smaller scales one may distinguish between independent histories at the subcontinental and basin scales. This permits a comparison of the relative importance of tectonic and climatic erosion processes affecting the different mountain belts of Asia during the Cenozoic.

Along the northern border of Africa, Pangea breakup has been diachronic. During the Jurassic, the Alpine Tethys propagated northeastward from the Atlantic to the Alps. During the Permian, the Neo‐Tethys propagated westward from Oman to northwestern Arabia. Then a secondary and late branch of Neo‐Tethys gave birth to the East Mediterranean basin. Finally the two oceans connected at end of Jurassic times, achieving the development of Africa northern plate boundary. By the Late Cretaceous, convergence between Africa and Eurasia led to the progressive closure of the Tethys realm. The continental collision is not completely achieved, and the different segments of the confrontation zone (Maghreb, central and East Mediterranean, Zagros, and Oman) expose different stages of the process. However, we emphasize the existence of synchronous geodynamic events from one end of the system to the other, although they do not have the same meaning. Two of them are particularly important. The Campanian‐Santonian (C‐S) event corresponds to (1) obduction and exhumation of high‐pressure–low‐temperature metamorphic rocks around the Arabian promontory, (2) inversion along the margins of the East Mediterranean basins, and (3) lithosphere buckling in the Atlas system (Maghreb) and adjacent Sahara platform. The middle‐late Eocene (MLE) event corresponds to (1) the onset of collision at the northern corner of Arabia, (2) the onset of slab retreat in the Mediterranean, and (3) inversion along the margin of the East Mediterranean as well as in the Atlas. The C‐S event coincides with a change in plate kinematics resulting in an abrupt increase of convergence velocity. The MLE event coincides with a period of strong coupling between the Africa and Eurasia plates and an abrupt decrease of convergence velocity. In the middle of the system, the central Mediterranean seems to escape to the effects of convergence and is the site of quite permanent extensional movements since the Triassic.

Sea surface reservoir ages must be known to establish a common chronological framework for marine, continental, and cryospheric paleoproxies, and are crucial for understanding ocean-continent climatic relationships and the paleoventilation of the ocean. Radiocarbon dates of planktonic foraminifera and tephra contemporaneously deposited over Mediterranean marine and terrestrial regions reveal that the reservoir ages were similar to the modern one (approximately 400 years) during most of the past 18,000 carbon-14 years. However, reservoir ages increased by a factor of 2 at the beginning of the last deglaciation. This is attributed to changes of the North Atlantic thermohaline circulation during the massive ice discharge event Heinrich 1.

VOLUME I: Fundamentals, Operations and Catalysts FLUID DYNAMICS IN MICROCHANNELS Multiphase Flow Microfluidic Networks Boiling and Two-Phase Flow in Microchannels Microscale Flow Visualization Modeling of Microfluidic Devices MIXING IN MICROSYSTEMS Characterization of Mixing and Segregation in Homogeneous Flow Systems Passive and Active Micromixers Mixing and Contacting of Heterogeneous Systems HEAT/MASS TRANSFER Heat Transfer in Homogeneous Systems Transport Phenomena in Microscale Reacting Flows Fluid-Fluid and Fluid-Solid Mass Transfer MICROSTRUCTURED DEVICES FOR PURIFICATION AND SEPARATION PROCESSES Extraction Capillary Electrochromatography MICROSTRUCTURED REACTORS Homogeneous Reactions Heterogeneous Multiphase Reactions Photoreactors Microstructured Reactors for Electrochemical Synthesis VOLUME II: Devices, Reactions and Applications MICROREACTOR DESIGN, FABRICATION AND ASSEMBLY Silicon and Glass Microreactors Metallic, Steel, Ceramic and Plastic Microreactors BULK AND FINE CHEMISTRY Liquid- and Liquid-Liquid-Phase Reactions - Aliphatic Substitution Reactions Liquid- and Liquid-Liquid-Phase Reactions - Aromatic Substitution Reactions Liquid- and Liquid-Liquid-Phase Reactions - Addition and Elimination Liquid- and Liquid-Liquid-Phase Reactions - Coupling Reactions Liquid- and Liquid-Liquid-Phase Reactions - Oxidations and Reduction Gas-Liquid-Phase Reactions: Substitution Gas-Liquid-Phase Reactions: Addition Gas-Liquid-Phase Reactions: Reduction Gas-Liquid-Phase Reactions: Miscellaneous Reactions POLYMERIZATION Free Radical Polymerization Living Radical Polymerization Cationic Polymerization Polycondensation FUNCTIONAL MATERIALS Organic Particles and Pigments Inorganic Particles Polymer Particles Microencapsulates, Proteins and Lipids/Vesicles Oil-in-Water and Water-in-Oil Emulsions Double, Triple and Complex Multilayered Emulsions Microreactor Applications in the Consumer Goods Industry FUEL PROCESSING Application and Operation of Microreactors for Fuel Conversion Steam Reforming Partial Oxidation CO Clean-Up: Water Gas Shift and Methanation Reactions CO Clean-Up: Preferential Oxidation VOLUME III: System, Process and Plant Engineering MICROREACTOR SYSTEMS DESIGN AND SCALE-UP Structured Multi-Scale Process Systems Design and Engineering - The Role of Microreactor Technology in Chemical Process Design Reaction and Process System Analysis, Miniaturization and Intensification Strategies Principles and Guidelines for Selection of Microstructured Devices for Mixing and Reaction Catalyst Development, Screening and Optimization SENSING, ANALYSIS, AND CONTROL Microtechnology and Process Analytics Optical In-Line Spectroscopy in Microchemical Processes On-Line Monitoring of Reaction Kinetics in Microreactors Using Mass Spectrometry and Micro-NMR Spectroscopy Automation and Control of Microprocess Systems MICROREACTOR PLANTS: CASE STUDIES Industrial Microreactor Process Development up to Production Microreactor Plant for the Large-Scale Production of a Fine Chemical Intermediate: A Technical Case Study Development and Scale-Up of a Microreactor Pilot Plant Using the Concept of Numbering-Up Microstructures as a Tool for Production in the Tons per Hour Scale ECONOMICS AND ECO-EFFICIENCY ANALYSES The Economic Potential of Microreaction Technology Life Cycle Assessment of Microreaction Technology Versus Batch Technology - A Case Study Exergy Analysis of a Micro Fuel Processing System for Hydrogen ald Electricity Production - A Case Study

Abstract. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) U–Pb geochronology of carbonate minerals, calcite in particular, is rapidly gaining popularity as an absolute dating method. The high spatial resolution of LA-ICP-MS U–Pb carbonate geochronology has benefits over traditional isotope dilution methods, particularly for diagenetic and hydrothermal calcite, because uranium and lead are heterogeneously distributed on the sub-millimetre scale. At the same time, this can provide limitations to the method, as locating zones of radiogenic lead can be time-consuming and “hit or miss”. Here, we present strategies for dating carbonates with in situ techniques, through imaging and petrographic techniques to data interpretation; our examples are drawn from the dating of fracture-filling calcite, but our discussion is relevant to all carbonate applications. We review several limitations to the method, including open-system behaviour, variable initial-lead compositions, and U–daughter disequilibrium. We also discuss two approaches to data collection: traditional spot analyses guided by petrographic and elemental imaging and image-based dating that utilises LA-ICP-MS elemental and isotopic map data.