bluuebunny/crossref_metadata_2025 huggingface dataset:
Lokale praktiseringer af den styrkede pædagogiske læreplan
Authors: Aabro Christian , Thingstrup Signe Hvid
Published: October 2024

Artiklen undersøger praktiseringen af Den styrkede pædagogiske læreplan i to daginstitutioner. Indførelsen af læreplanen var bl.a. drevet af et politisk ønske om kvalitetssikring og harmonisering af pædagogikken i daginstitutioner gennem standardiserede, detaljerede mål. Gennem analyser af empiri fra to daginstitutioner vises det imidlertid, at læreplanen praktiseres meget forskelligt. Med Balls begreb om praktisering (enactment) viser vi, at praktiseringen af læreplanen bygger på lokale fortolkninger, der især formes af diskursive konstruktioner af børn og familiers behov. På den baggrund diskuterer vi læreplanens bidrag til institutionel produktion af ulighed. AbstractLocal enactments of Danish ECE-curriculumThis article examines how the Danish national curriculum for early childhood education (ECE) is enacted in two nurseries. The introduction of the curriculum was, a.o., driven by political aims of quality and harmonization of pedagogy in ECE through standardized educational goals. Research indicates that this increased governance leads to instrumentalization of pedagogy, shifts in pedagogical prioritizations, and limits pedagogues’ professional judgment and discretion. Through analyses of empirical material from two nurseries we show, however, that curriculum is practiced very differently. With Ball’s concept of enactment, we show that pedagogues’ enactments of the curriculum build on local interpretations that are shaped by discursive constructions of the needs of children and families. We discuss how this contributes to institutional production of inequity.
Численный метод определения несущей способности плоских вращающихся армированных дисков
Authors: Янковский Андрей Петрович
Published: October 2024

An extremal problem of determining the upper (kinematic) limit of the load-bearing capacity of a flat disk reinforced with continuous fibers and rotating in a quasi-steady state is formulated. At the inner edge, the disk blade is rigidly attached to the shaft (or hub), and reinforced vanes can be attached to its outer edge. The materials of the composition phases are assumed to be rigid-plastic, having different yield limits in tension and compression; the binder matrix material may be cylindrically orthotropic. Under conditions of a generalized plane stress state, the yield curves of the components of the composition in the principal stresses are piecewise linear. Reinforcement structures have radial and axial symmetry. The plastic deformation of the composition is calculated using the relations of the structural model of the mechanics of composites, which takes into account the plane stress state in all phase materials. The problem was discretized and a numerical algorithm for solving it was developed, based on the use of linear programming methods. Various variants of discretization of the problem under consideration have been studied. The convergence of the numerical solution and its good agreement with the previously obtained analytical solution are demonstrated. Numerical examples of calculating the maximum angular velocity of rotation of disks for different reinforcement structures of their fabric are analyzed. Cases of laying fibers along straight trajectories (geodesic lines), along logarithmic spirals, as well as along radial and circumferential directions are considered. In this case, the isotropic materials of the components of the composition obey the associated flow law corresponding to the yield criterion Hu. The influence of reinforcement parameters (directions and densities) on the bearing capacity of rotating disks has been studied. The comparison was carried out for composite disks of the same mass and with the same relative volume of reinforcement.
Сравнение динамических характеристик пьезокерамических актуаторов, применяемых в вибродиагностике крупномасштабных конструкций
Authors: Шардаков Игорь Николаевич , Шестаков Алексей Петрович , Глот Ирина Олеговна , Гусев Георгий Николаевич , Епин Валерий Валерьевич , Цветков Роман Валерьевич
Published: October 2024

One of the effective methods of non-destructive testing of large-scale structures is active vibration diagnostics. It involves local dynamic impact on the structure and recording structural vibration response. Analysis of a set of responses recorded at different points allows determining the mechanical condition of an object under study. According to the method of active vibration diagnostics, dynamic influences are realized by special devices – actuators. Today, most widely used are piezoceramic actuators. As a rule, they are a piezoceramic plate embedded in the structure or located on its surface. Previously, the authors have proposed a piezoceramic actuator with attached mass, which is able to create more intense impact on the structure. In this work, numerical modeling is applied to evaluate the effectiveness of a modified device in comparison with traditional devices using a concrete slab and a model 4-story building as examples. Based on the results obtained, it is concluded that the elastic waves, excited by the actuators of three types mentioned here, are of significantly different intensity. The piezoceramic plate placed on the surface of the structure provides the wave with the lowest amplitude. It is 1.9 times smaller than for the plate embedded in the structure and 12 times smaller than for the plate with attached mass. The numerical experiment, which demonstrates the propagation of an elastic wave in the components of the model building, made it possible to evaluate the intensity of vibrations at different distances from a vibration source. For the actuator with attached mass, the amplitude of acceleration at the point placed at a distance of 1.7 meters from the actuator is 20 m/s2; 5.2 meters – 5 m/s2; 8.7 meters – 2 m/s2. These accelerations can be reliably measured by most modern accelerometers. Thus, a piezoceramic actuator with attached mass is the most promising device for active vibration diagnostics of large-scale concrete structures. The use of such actuators in the monitoring system reduces the total number of actuators and sensors due to increasing the distance between them.
Solidification Process Modeling of Equiaxed Investment Castings with Transient Nonuniform Boundary Condition Definition
Authors: Olson Weston , Stemmler Michael , Fernandez Erik , Kapat Jayanta
Published: October 2024

The equiaxed investment casting process is a multi-physics problem which requires knowledge from engineers who have expertise in materials, metallurgy, fluid dynamics, thermodynamics, and heat transfer. Process modeling is a tool used by foundries to help predict casting defects such as shrinkage porosity, hot tears, and poor grain structure. The reliability of these predictions is strongly dependent on the accuracy of the thermal boundary conditions set in the model. In this work, a SGT5-2000E Vane 4 cast in Rene 80 nickel-based superalloy was modeled, using the FEA simulation package ProCAST, with two different methodologies. One methodology had very little effort invested into defining the thermal domain. The other methodology involved a thorough consideration of all heat transfer mechanisms acting on the mold. An extensive literature search was performed to define a unique natural convection heat transfer coefficient for each set of surfaces on the mold. The transient boundary layer development was also captured in the definition of the heat conditions. The shrinkage porosity predictions of the models were compared to real-world x-ray data and the transient nonuniform methodology predictions were much more representative than the low fidelity heat transfer methodology predictions. The low fidelity heat transfer model did predict some shrinkage, but not where it appeared in reality. The process modeler will be misdirected by the model results when deriving a solution to the casting process if the real-world physics are not appropriately accounted for in the model. This will be very counterproductive when the foundry is using the model to reduce developmental trials by running trials in model space. References and derived parameters are provided for material properties, emissivity of shell and insulation wraps, and external mold spatially varying heat transfer coefficients.
Human poses recognition based on Spiking Pulse Graph Neural Networks
Authors: Qu Shenming , Li He , Pang Zilong
Published: October 2024

The temporal dilated convolutional model usually requires a large amount of computing resources in the human pose recognition task, especially when the input image information is too complex, which will lead to the shortcomings of low accuracy and large model energy consumption. Addressing these issues, we designed a new human poses recognition Spiking Pulse Graph Neural Networks model. In this model, we increase the receptive field of the model by changing the expansion coefficient and activation function of the convolution in the model receptive field processing module, so as to make the extracted features more accurate. The transmission rate of feature information is controlled by the Spiking Pulse Graph Neural Networks model with the reward mechanism of human pose learning rate, which is used to improve the accuracy of the model and reduce the energy loss of the model. Compared with the temporal dilated convolutional model and the latest human pose recognition method, the accuracy of human pose recognition is improved and the energy consumption is reduced under the same test set data.
A retrospective analysis of a newly proposed imaging-etiologic classification for acute ischemic stroke with large vascular occlusion based on MRI and pathogenesis
Authors: Li Hao , Li Zhaoshuo , Xia Jinchao , Shen Lijun , Duan Guangming , Wang Ziliang
Published: October 2024

Background

Endovascular treatment (EVT) has emerged as the preferred initial therapeutic option for acute ischemic stroke (AIS) with large vascular occlusion (LVO). To facilitate more targeted EVT interventions, we propose a novel imaging-etiologic classification system derived from a comprehensive analysis of preoperative MRI and pathogenesis in AIS patients.

Methods

From June 2020 to December 2021, a retrospective analysis was conducted on 184 consecutive AIS patients who underwent preoperative MRI and subsequent EVT at the Henan Provincial Cerebrovascular Hospital Stroke Center. Patients’ medical histories were comprehensively reviewed. According to MRI, anterior circulation infarction (ACI) and posterior circulation infarction (PCI) were divided into four groups respectively (A-D & a-d). Three types (1–3) of etiology were identified based on pathogenesis. The types were respectively evaluated by screening test with intra-operative finding of EVT.

Results

Our imaging-etiologic classification achieved an overall positive rate of 90.2% (166/184) when compared to the gold standard. The screening test for each type demonstrated excellent validity (Youden’s index ≥ 0.75) and reliability (Kappa ≥ 0.80).

Conclusion

The imaging-etiologic classification represents a simple yet comprehensive approach that can be readily applied in the management of AIS with LVO. It can rapidly and effectively locate the vascular occlusion, and reveal the pathogenesis.
Ceciamaralia, a new genus of Dorvilleidae (Annelida) from deep waters of the Southwest Atlantic Ocean and an insight into its relationship within the family
Authors: Bonaldo Rafael de Oliveira , Steiner Tatiana Menchini , Garraffoni André Rinaldo Senna
Published: October 2024

Dorvilleidae Chamberlin, 1919 is a family of Annelida containing some of the smallest ‘polychaetes’ species, being poorly studied worldwide, and with little knowledge regarding its diversity and occurrence. Samples obtained in oceanographic campaigns performed in the Southwest Atlantic Ocean (Brazilian coast) revealed a high number of specimens of dorvilleids, adding to our knowledge of the family’s biodiversity. A detailed morphological analysis of these organisms has revealed a new genus, Ceciamaralia gen. nov., with two new species. The new genus differs from other Dorvilleidae genera in (i) the robust and enlarged pharynx which are frequently everted, (ii) unique composition of maxillae, with an elongated pair of serrated basal plates and one pair of anterior free maxillary plates with a long and thin anterior spine and (iii) ventral cirri present only in few first chaetigers. Ceciamaralia lanai gen. et sp. nov. is characterized by the presence of a broad and large dorsal cirrus on a few anterior parapodia and by furcate chaeta in supra-acicular fascicles. While Ceciamaralia nonatoi gen. et sp. nov. presents one geniculate chaeta instead of one furcate, the absence of dorsal cirri and, in some specimens, the absence of palps. A cladistic analysis supported the monophyly of Ceciamaralia gen. nov. by four synapomorphies related to the unique morphology of its maxillae, pharynx and appendages. This study is part of several recent taxonomic studies aiming to elucidate and increase the knowledge of Dorvilleidae, since it is part of a Ph.D project focused on the family.
Evaluating RET-Hb vs Hb in Predicting Early Response in Oral Iron Therapy: A Prospective Interventional Study
Authors: Mathew Benita Mary , Santhakumar Rati , Innah Susheela Jacob , Cherian Vinod Jacob , Rafi Aboobaker Mohamed
Published: October 2024

Introduction: Children are more vulnerable to anaemia due to their rapid growth, which requires an expanding erythroid mass and a high tissue iron demand. Anaemia can negatively impact psychomotor and cognitive development and can lead to a decline in immunity. Reticulocytes are precursors to erythrocytes and make up about 1% (ranging from 0.5% to 2.5%) of circulating erythrocytes. The reticulocyte content serves as a measurement of haemoglobin within the reticulocyte and correlates directly with the functional availability of iron in the bone marrow. Consequently, it is considered one of the strongest predictors of Iron Deficiency (ID). The Reticulocyte Haemoglobin Content (RET-Hb) level is useful for diagnosing anaemia before it clinically manifests in a patient. Aim: To assess the effectiveness of RET-Hb content as a predictor for early response to oral iron therapy in comparison to haemoglobin levels. Materials and Methods: This prospective interventional study was conducted in the Department of Paediatrics at a tertiary care Hospital in Thrissur, Central Kerala, India, over a period of 18 months, from December 2019 to June 2021. A total of 44 samples were included in the study, and socio-demographic details were collected using a semistructured proforma from patients with haemoglobin levels below the mean reference value. Baseline haemogram parameters {Mean Corpuscular Volume (MCV), Mean Corpuscular Haemoglobin (MCH), Mean Corpuscular Haemoglobin Concentration (MCHC), Red Cell Distribution Width (RDW), Haemtocrit (HCT)}, reticulocyte indices, and ferritin levels were measured before administering oral iron therapy (T0). These parameters were reassessed after seven days (T1) and 30 days (T2) following the initiation of therapy. The Chi-square test was used to assess the association between various factors, and Pearson’s correlation coefficient was utilised to find the correlation. Results: The mean age of the participants was 3.46±2.2 years, with 24 males and 20 females included in the study. The mean RET-Hb was 21.15±1.71 pg before the initiation of treatment, which significantly increased to 23.37±1.95 pg and 25.77±1.56 pg at days 7 and 30, respectively. The haemoglobin level increased from 8.37±1.25 g/L to 8.55±1.19 g/L and 9.72±0.98 g/L at T1 and T2, respectively, which was statistically significant. The Absolute Reticulocyte Count (RET#) also showed a significant early increase after initiating treatment. Conclusion: These findings indicate that RET-Hb and RET# are reliable early predictors of response to iron therapy, alongside haemoglobin levels, and can be used as effective alternatives.
A Review on Role of Beneficial Insects in Sustainable Crop Production Systems
Authors: Jarpla Mounika , Kumari Pooja , Pawar Priyanshu , Reddy N. Aswathanarayana , Bhargavi Chinnapogula , Samreen  , Aniket  , E Vasanthan
Published: October 2024

Beneficial insects are vital components of sustainable crop production systems, providing key ecosystem services such as biological pest control, pollination, and soil health enhancement. This review explores the diverse roles of beneficial insects, including predators, parasitoids, pollinators, and soil engineers, in promoting sustainable agriculture. Predators and parasitoids regulate pest populations, reducing the need for chemical pesticides, while pollinators, such as bees and butterflies, enhance crop yields and quality through effective pollination. Soil-dwelling insects contribute to nutrient cycling and soil structure, improving plant health and productivity. Despite their numerous benefits, the effective integration of beneficial insects is challenged by knowledge gaps in ecological interactions, high implementation costs, and environmental pressures such as habitat loss and pesticide exposure. Strategies to overcome these challenges include habitat management (e.g., establishing flower strips and hedgerows), conservation biological control, and augmentative releases of natural enemies. Sustainable practices like crop rotation and intercropping can increase habitat heterogeneity, supporting beneficial insect diversity. Should focus on Integrated Pest and Pollinator Management (IPPM) to optimize both pest suppression and pollination services. Advancements in digital technologies, such as remote sensing and precision agriculture, can improve monitoring and deployment strategies for beneficial insects. Supportive policies and educational initiatives are necessary to encourage farmers to adopt insect-friendly practices.
Disturbance Impacts on Thermal Hot Spots and Hot Moments at the Peatland‐Atmosphere Interface
Authors: Leonard R. M. , Kettridge N. , Devito K. J. , Petrone R. M. , Mendoza C. A. , Waddington J. M. , Krause S.
Published: December 2017

Soil‐surface temperature acts as a master variable driving nonlinear terrestrial ecohydrological, biogeochemical, and micrometeorological processes, inducing short‐lived or spatially isolated extremes across heterogeneous landscape surfaces. However, subcanopy soil‐surface temperatures have been, to date, characterized through isolated, spatially discrete measurements. Using spatially complex forested northern peatlands as an exemplar ecosystem, we explore the high‐resolution spatiotemporal thermal behavior of this critical interface and its response to disturbances by using Fiber‐Optic Distributed Temperature Sensing. Soil‐surface thermal patterning was identified from 1.9 million temperature measurements under undisturbed, trees removed and vascular subcanopy removed conditions. Removing layers of the structurally diverse vegetation canopy not only increased mean temperatures but it shifted the spatial and temporal distribution, range, and longevity of thermal hot spots and hot moments. We argue that linking hot spots and/or hot moments with spatially variable ecosystem processes and feedbacks is key for predicting ecosystem function and resilience.
An Adjoint Sensitivity Method Applied to Time Reverse Imaging of Tsunami Source for the 2009 Samoa Earthquake
Authors: Hossen M. Jakir , Gusman Aditya , Satake Kenji , Cummins Phil R.
Published: December 2017

We have previously developed a tsunami source inversion method based on “Time Reverse Imaging” and demonstrated that it is computationally very efficient and has the ability to reproduce the tsunami source model with good accuracy using tsunami data of the 2011 Tohoku earthquake tsunami. In this paper, we implemented this approach in the 2009 Samoa earthquake tsunami triggered by a doublet earthquake consisting of both normal and thrust faulting. Our result showed that the method is quite capable of recovering the source model associated with normal and thrust faulting. We found that the inversion result is highly sensitive to some stations that must be removed from the inversion. We applied an adjoint sensitivity method to find the optimal set of stations in order to estimate a realistic source model. We found that the inversion result is improved significantly once the optimal set of stations is used. In addition, from the reconstructed source model we estimated the slip distribution of the fault from which we successfully determined the dipping orientation of the fault plane for the normal fault earthquake. Our result suggests that the fault plane dip toward the northeast.
Dominant Role of Atlantic Multidecadal Oscillation in the Recent Decadal Changes in Western North Pacific Tropical Cyclone Activity
Authors: Zhang Wei , Vecchi Gabriel A. , Murakami Hiroyuki , Villarini Gabriele , Delworth Thomas L. , Yang Xiaosong , Jia Liwei
Published: December 2017

Over the 1997–2014 period, the mean frequency of western North Pacific (WNP) tropical cyclones (TCs) was markedly lower (~18%) than the period 1980–1996. Here we show that these changes were driven by an intensification of the vertical wind shear in the southeastern/eastern WNP tied to the changes in the Walker circulation, which arose primarily in response to the enhanced sea surface temperature (SST) warming in the North Atlantic, while the SST anomalies associated with the negative phase of the Pacific Decadal Oscillation in the tropical Pacific and the anthropogenic forcing play only secondary roles. These results are based on observations and experiments using the Geophysical Fluid Dynamics Laboratory Forecast‐oriented Low‐ocean Resolution Coupled Climate Model coupled climate model. The present study suggests a crucial role of the North Atlantic SST in causing decadal changes to WNP TC frequency.
Three‐Dimensional Sediment Dynamics in Well‐Mixed Estuaries: Importance of the Internally Generated Overtide, Spatial Settling Lag, and Gravitational Circulation
Authors: Wei Xiaoyan , Kumar Mohit , Schuttelaars Henk M.
Published: December 2017

To investigate the dominant sediment transport and trapping mechanisms, a semi‐analytical three‐dimensional model is developed resolving the dynamic effects of salt intrusion on sediment in well‐mixed estuaries in morphodynamic equilibrium. As a study case, a schematized estuary with a converging width and a channel‐shoal structure representative for the Delaware estuary is considered. When neglecting Coriolis effects, sediment downstream of the estuarine turbidity maximum (ETM) is imported into the estuary through the deeper channel and exported over the shoals. Within the ETM region, sediment is transported seaward through the deeper channel and transported landward over the shoals. The largest contribution to the cross‐sectionally integrated seaward residual sediment transport is attributed to the advection of tidally averaged sediment concentrations by river‐induced flow and tidal return flow. This contribution is mainly balanced by the residual landward sediment transport due to temporal correlations between the suspended sediment concentrations and velocities at the M2 tidal frequency. The M2 sediment concentration mainly results from spatial settling lag effects and asymmetric bed shear stresses due to interactions of M2 bottom velocities and the internally generated M4 tidal velocities, as well as the salinity‐induced residual currents. Residual advection of tidally averaged sediment concentrations also plays an important role in the landward sediment transport. Including Coriolis effects hardly changes the cross‐sectionally integrated sediment balance, but results in a landward (seaward) sediment transport on the right (left) side of the estuary looking seaward, consistent with observations from literature. The sediment transport/trapping mechanisms change significantly when varying the settling velocity and river discharge.
Brine Convection, Temperature Fluctuations, and Permeability in Winter Antarctic Land‐Fast Sea Ice
Authors: Wongpan P. , Hughes K. G. , Langhorne P. J. , Smith I. J.
Published: December 2017

Vertical temperature strings are used in sea ice research to study heat flow, ice growth rate, and ocean‐ice‐atmosphere interaction. We demonstrate the feasibility of using temperature fluctuations as a proxy for fluid movement, a key process for supplying nutrients to Antarctic sea ice algal communities. Four strings were deployed in growing, land‐fast sea ice in McMurdo Sound, Antarctica. By smoothing temperature data with the robust LOESS method, we obtain temperature fluctuations that cannot be explained by insolation or atmospheric heat loss. Statistical distributions of these temperature fluctuations are investigated with sensitivities to the distance from the ice‐ocean interface, average ice temperature, and sea ice structure. Fluctuations are greatest close to the base (<50 mm) at temperatures >−3°C, and are discrete events with an average active period of 43% compared to 11% when the ice is colder (–3°C to −5°C). Assuming fluctuations occur when the Rayleigh number, derived from mushy layer theory, exceeds a critical value of 10 we approximate the harmonic mean permeability of this thick (>1 m) sea ice in terms of distance from the ice‐ocean interface. Near the base, we obtain values in the same range as those measured by others in Arctic spring and summer. The permeability between the ice‐ocean interface and 0.05 ± 0.04 m above it is of order 10−9 m2. Columnar and incorporated platelet ice permeability distributions in the bottom 0.1 m of winter Antarctic sea ice are statistically significantly different although their arithmetic means are indistinguishable.
Storm Surge Reconstruction and Return Water Level Estimation in Southeast Asia for the 20th Century
Authors: Cid Alba , Wahl Thomas , Chambers Don P. , Muis Sanne
Published: December 2017

We present a methodology to reconstruct the daily maximum storm surge levels, obtained from tide gauges, based on the surrounding atmospheric conditions from an atmospheric reanalysis (20th Century Reanalysis—20CR). Tide gauge records in Southeast Asia are relatively short, so this area is often underrepresented in studies based on long observational records, and there are just a few studies that have analyzed storm surge trends, variability or return water levels (RWLs) from numerical models in this area. Here we develop, calibrate, and validate a multivariate linear regression model that relates the storm surge with the principal components of the local atmospheric conditions. This allows us to reconstruct storm surges for the 147 year 20CR period (1866–2012) and therefore to calculate more robust RWLs from the entire simulated data set and subsets thereof. RWLs are obtained by fitting the monthly maxima values to the Generalize Extreme Value (GEV) distribution. We find an increase in the 50 year RWL from the second half of the 19th century to the present unrelated to mean sea level; this increase is less noticeable when comparing only recent periods. Therefore, further research is needed since there is evidence that atmospheric reanalyses can include spurious trends in the late 19th and early 20th. RWLs obtained from the statistical reconstruction are validated against the ones obtained from observations and from a numerical model. Agreements are generally higher when using surge levels from the statistical model, even before its calibration.
Remote Sensing of Waves Propagating in the Marginal Ice Zone by SAR
Authors: Shen Hui , Perrie William , Hu Yongcun , He Yijun
Published: December 2017

Wave‐ice interactions are important in high sea state conditions, when waves propagate from the open ocean into the marginal ice zone (MIZ) and the pack ice. In situ observations of waves and wave‐ice interactions can be obtained at a small number of MIZ locations in costly and challenging experiments, whereas remote sensing using satellite RADARSAT‐2 SAR (synthetic aperture radar) images can observe waves throughout the MIZ, in all weather conditions. We present a methodology to retrieve MIZ wave parameters from polarimetric SAR data. As an application, we describe the characteristics of waves propagating from open water into the MIZ, as generated by a strong low pressure system that developed to the east of Greenland. As waves penetrate the MIZ, SAR remote sensing observations suggest increased dominant wavelengths, attenuated wave energy and shifted mean wave directions. The SAR observations and estimates for retrieved wave attenuation in the MIZ are shown to be consistent with wave attenuation theory and in situ field observations. Thus, valuable estimates of MIZ waves over large spatial scales at high‐resolution are provided by the SAR measurements.
Greater Role of Geostrophic Currents in Ekman Dynamics in the Western Arctic Ocean as a Mechanism for Beaufort Gyre Stabilization
Authors: Zhong Wenli , Steele Michael , Zhang Jinlun , Zhao Jinping
Published: December 2017

Seven different methods, with and without including geostrophic currents, were used to explore Ekman dynamics in the western Arctic Ocean for the period 1992–2014. Results show that surface geostrophic currents have been increasing and are much stronger than Ekman layer velocities in recent years (2003–2014) when the oceanic Beaufort Gyre (BG) is spinning up in the region. The new methods that include geostrophic currents result in more realistic Ekman pumping velocities than a previous iterative method that does not consider geostrophic currents and therefore overestimates Ekman pumping velocities by up to 52% in the central area of the BG over the period 2003–2014. When the BG is spinning up as seen in recent years, geostrophic currents become stronger, which tend to modify the ice‐ocean stress and moderate the wind‐driven Ekman convergence in the Canada Basin. This is a mechanism we have identified to play an important and growing role in stabilizing the Ekman convergence and therefore the BG in recent years. This mechanism may be used to explain three scenarios that describe the interplay of changes in wind forcing, sea ice motion, and geostrophic currents that control the variability of the Ekman dynamics in the central BG during 1992–2014. Results also reveal several upwelling regions in the southern and northern Canada Basin and the Chukchi Abyssal Plain which may play a significant role in physical and biological processes in these regions.
Spatial and Temporal Patterns of Chlorophyll Concentration in the Southern California Bight
Authors: Nezlin Nikolay P. , McLaughlin Karen , Booth J. Ashley T. , Cash Curtis L. , Diehl Dario W. , Davis Kristen A. , Feit Adriano , Goericke Ralf , Gully Joseph R. , Howard Meredith D. A. , Johnson Scott , Latker Ami , Mengel Michael J. , Robertson George L. , Steele Alex , Terriquez Laura , Washburn Libe , Weisberg Stephen B.
Published: December 2017

Distinguishing between local, anthropogenic nutrient inputs and large‐scale climatic forcing as drivers of coastal phytoplankton biomass is critical to developing effective nutrient management strategies. Here we assess the relative importance of these two drivers by comparing trends in chlorophyll‐a between shallow coastal (0.1–16.5 km) and deep offshore (17–700 km) areas, hypothesizing that coastal regions influenced by anthropogenic nutrient inputs may have different spatial and temporal patterns in chlorophyll‐a concentration from offshore regions where coastal inputs are less influential. Quarterly conductivity‐temperature‐depth (CTD) fluorescence measurements collected from three southern California continental shelf regions since 1998 were compared to chlorophyll‐a data from the more offshore California Cooperative Fisheries Investigations (CalCOFI) program. The trends in the coastal zone were similar to those offshore, with a gradual increase of chlorophyll‐a biomass and shallowing of its maximum layer since the beginning of observations, followed by chlorophyll‐a declining and deepening from 2010 to present. An exception was the northern coastal part of SCB, where chlorophyll‐a continued increasing after 2010. The long‐term increase in chlorophyll‐a prior to 2010 was correlated with increased nitrate concentrations in deep waters, while the recent decline was associated with deepening of the upper mixed layer, both linked to the low‐frequency climatic cycles of the Pacific Decadal Oscillation and North Pacific Gyre Oscillation. These large‐scale factors affecting the physical structure of the water column may also influence the delivery of nutrients from deep ocean outfalls to the euphotic zone, making it difficult to distinguish the effects of anthropogenic inputs on chlorophyll along the coast.
Uncertainties in Climatological Seawater Density Calculations
Authors: Dai Hao , Zhang Xining
Published: December 2017

In most applications, with seawater conductivity, temperature, and pressure data measured in situ by various observation instruments e.g., Conductivity‐Temperature‐Depth instruments (CTD), the density which has strong ties to ocean dynamics and so on is computed according to equations of state for seawater. This paper, based on density computational formulae in the Thermodynamic Equation of Seawater 2010 (TEOS‐10), follows the Guide of the expression of Uncertainty in Measurement (GUM) and assesses the main sources of uncertainties. By virtue of climatological decades‐average temperature/Practical Salinity/pressure data sets in the global ocean provided by the National Oceanic and Atmospheric Administration (NOAA), correlation coefficients between uncertainty sources are determined and the combined standard uncertainties
in seawater density calculations are evaluated. For grid points in the world ocean with 0.25° resolution, the standard deviations of
in vertical profiles cover the magnitude order of 10−4 kg m−3. The
means in vertical profiles of the Baltic Sea are about 0.028kg m−3 due to the larger scatter of Absolute Salinity anomaly. The distribution of the
means in vertical profiles of the world ocean except for the Baltic Sea, which covers the range of
kg m−3, is related to the correlation coefficient
between Absolute Salinity
and pressure
. The results in the paper are based on sensors' measuring uncertainties of high accuracy CTD. Larger uncertainties in density calculations may arise if connected with lower sensors' specifications. This work may provide valuable uncertainty information required for reliability considerations of ocean circulation and global climate models.
Emergent Behavior of Arctic Precipitation in Response to Enhanced Arctic Warming
Authors: Anderson Bruce T. , Feldl Nicole , Lintner Benjamin R.
Published: December 2017

Amplified warming of the high latitudes in response to human‐induced emissions of greenhouse gases has already been observed in the historical record and is a robust feature evident across a hierarchy of model systems, including the models of the Coupled Model Intercomparison Project Phase 5 (CMIP5). The main aims of this analysis are to quantify intermodel differences in the Arctic amplification (AA) of the global warming signal in CMIP5 RCP8.5 (Representative Concentration Pathway 8.5) simulations and to diagnose these differences in the context of the energy and water cycles of the region. This diagnosis reveals an emergent behavior between the energetic and hydrometeorological responses of the Arctic to warming: in particular, enhanced AA and its associated reduction in dry static energy convergence is balanced to first order by latent heating via enhanced precipitation. This balance necessitates increasing Arctic precipitation with increasing AA while at the same time constraining the magnitude of that precipitation increase. The sensitivity of the increase, ~1.25 (W/m2)/K (~240 (km3/yr)/K), is evident across a broad range of historical and projected AA values. Accounting for the energetic constraint on Arctic precipitation, as a function of AA, in turn informs understanding of both the sign and magnitude of hydrologic cycle changes that the Arctic may experience.
Evaluation of Real‐Time Convection‐Permitting Precipitation Forecasts in China During the 2013–2014 Summer Season
Authors: Zhu Kefeng , Xue Ming , Zhou Bowen , Zhao Kun , Sun Zhengqi , Fu Peiling , Zheng Yongguang , Zhang Xiaoling , Meng Qingtao
Published: December 2017

Forecasts at a 4 km convection‐permitting resolution over China during the summer season have been produced with the Weather Research and Forecasting model at Nanjing University since 2013. Precipitation forecasts from 2013 to 2014 are evaluated with dense rain gauge observations and compared with operational global model forecasts. Overall, the 4 km forecasts show very good agreement with observations over most parts of China, outperforming global forecasts in terms of spatial distribution, intensity, and diurnal variation. Quantitative evaluations with the Gilbert skill score further confirm the better performance of the 4 km forecasts over global forecasts for heavy precipitation, especially for the thresholds of 100 and 150 mm d−1. Besides bulk characteristics, the representations of some unique features of summer precipitation in China under the influence of the East Asian summer monsoon are further evaluated. These include the northward progression and southward retreat of the main rainband through the summer season, the diurnal variations of precipitation, and the meridional and zonal propagation of precipitation episodes associated with background synoptic flow and the embedded mesoscale convective systems. The 4 km forecast is able to faithfully reproduce most of the features while overprediction of afternoon convection near the southern China coast is found to be a main deficiency that requires further investigations.
Enhancement of PM2.5 Concentrations by Aerosol‐Meteorology Interactions Over China
Authors: Zhang Xin , Zhang Qiang , Hong Chaopeng , Zheng Yixuan , Geng Guannan , Tong Dan , Zhang Yuxuan , Zhang Xiaoye
Published: December 2017

Aerosol‐meteorology interactions can change surface aerosol concentrations via different mechanisms such as altering radiation budget or cloud microphysics. However, few studies investigated the impacts of different mechanisms on temporal and spatial distribution of PM2.5 concentrations over China. Here we used the fully coupled Weather Research and Forecasting model with online chemistry (WRF‐Chem) to quantify the enhancement of PM2.5 concentrations by aerosol‐meteorology feedback in China in 2014 for different seasons and separate the relative impacts of aerosol radiation interactions (ARIs) and aerosol‐cloud interactions (ACIs). We found that ARIs and ACIs could increase population‐weighted annual mean PM2.5 concentration over China by 4.0 μg/m3 and 1.6 μg/m3, respectively. We found that ARIs play a dominant role in aerosol‐meteorology interactions in winter, while the enhancement of PM2.5 concentration by ARIs and ACIs is comparable in other three seasons. ARIs reduced the wintertime monthly mean wind speed and planetary boundary layer (PBL) height by up to 0.1 m/s and 160 m, respectively, but increased the relative humidity by up to 4%, leading to accumulation of pollutants within PBL. Also, ARIs reduced dry deposition velocity of aerosols by up to 20%, resulting in an increase in PM2.5 lifetime and concentrations. ARIs can increase wintertime monthly mean surface PM2.5 concentration by a maximum of 30 μg/m3 in Sichuan Basin. ACIs can also increase PM2.5 concentration with more significant impacts in wet seasons via reduced wet scavenging and enhanced in‐cloud chemistry. Dominant processes in PM2.5 enhancement are also clarified in different seasons. Results show that physical process is more important than chemical processes in winter in ARIs, while chemical process of secondary inorganic aerosols production may be crucial in wet seasons via ACIs.
Diurnal Course of Evaporation From the Dead Sea in Summer: A Distinct Double Peak Induced by Solar Radiation and Night Sea Breeze
Authors: Lensky N. G. , Lensky I. M. , Peretz A. , Gertman I. , Tanny J. , Assouline S.
Published: December 2017

Partitioning between the relative effects of the radiative and aerodynamic components of the atmospheric forcing on evaporation is challenging since diurnal distributions of wind speed and solar radiation typically overlap. The Dead Sea is located about a 100 km off the Eastern Mediterranean coast, where and the Mediterranean Sea breeze front reaches it after sunset. Therefore, in the Dead Sea the peaks of solar radiation and wind speed diurnal cycles in the Dead Sea are distinctly separated in time, offering a unique opportunity to distinguish between their relative impacts on evaporation. We present mid‐summer eddy covariance and meteorological measurements of evaporation rate and surface energy fluxes over the Dead Sea. The evaporation rate is characterized by a clear diurnal cycle with a daytime peak, few hours after solar radiation peak, and a nighttime peak coincident with wind speed peak. Evaporation rate is minimum during sunrise and sunset. Measurements of evaporation rate from two other water bodies that are closer to the Mediterranean coast, Eshkol Reservoir, and Lake Kinneret, present a single afternoon peak, synchronous with the sea breeze. The inland diurnal evaporation rate cycle varies with the distance from the Mediterranean coast, following the propagation of sea breeze front: near the coast, wind speed, and radiation peaks are close and consequently a single daily evaporation peak appears in the afternoon; at the Dead Sea, about a 100 km inland, the sea breeze front arrives at sunset, resulting in a diurnal evaporation cycle characterized by a distinct double peak.
Rapamycin prevents cerebral stroke by modulating apoptosis and autophagy in penumbra in rats
Authors: Wu Meiling , Zhang Huadan , Kai Jiejing , Zhu Feng , Dong Jingyin , Xu Ziwei , Wong Michael , Zeng Ling‐Hui
Published: December 2017

Objective

Whether activation or inhibition of the mTOR pathway is beneficial to ischemic injury remains controversial. It may result from the different reaction of ischemic penumbra and core to modulation of mTOR pathway after cerebral ischemia–reperfusion injury in rats.

Methods

Longa's middle cerebral artery occlusion (MCAO) method was conducted to induce the focal cerebral ischemia–reperfusion. Western blot analysis was used to examine the protein expression involving mTOR pathway, apoptosis, and autophagy‐related proteins. TTC staining and Fluoro‐Jade B staining was conducted to detect the infarct volume and cell apoptosis, respectively. Neurological function was measured by modified neurological severity score and left‐biased swing.

Results

mTOR signaling pathway was activated in ischemic penumbra and decreased in ischemic core after ischemia and ischemia–reperfusion. Ischemia–reperfusion injury induced the increase in cleaved caspase 9 and caspase 3 both in ischemic penumbra and in ischemic core, whereas the expression of phosphorylated ULK1, Beclin 1 and LC3‐II was decreased. Rapamycin pre or postadministration inhibited the overactivation of mTOR pathway in ischemic penumbra. Ameliorated neurological function and reduced infarct volume were observed after pre or postrapamycin treatment. Rapamycin markedly decreased the number of FJB‐positive cells and the expression of cleaved caspase‐3 and cleaved caspase‐9 proteins as well as increased the activation of autophagy reflected by ULK1, Beclin‐1 and LC3.

Interpretation

mTOR signaling pathway was activated in ischemic penumbra after cerebral ischemia–reperfusion injury in rats. mTOR inhibitor rapamycin significantly decreased the mTOR activation and infarct volume and subsequently improved neurological function. These results may relate to inhibition of neuron apoptosis and activation of autophagy.
Biomimetic Tissue‐Engineered Bone Substitutes for Maxillofacial and Craniofacial Repair: The Potential of Cell Sheet Technologies
Authors: Kawecki Fabien , Clafshenkel William P. , Fortin Michel , Auger François A. , Fradette Julie
Published: December 2017

Maxillofacial defects are complex lesions stemming from various etiologies: accidental, congenital, pathological, or surgical. A bone graft may be required when the normal regenerative capacity of the bone is exceeded or insufficient. Surgeons have many options available for bone grafting including the “gold standard” autologous bone graft. However, this approach is not without drawbacks such as the morbidity associated with harvesting bone from a donor site, pain, infection, or a poor quantity and quality of bone in some patient populations. This review discusses the various bone graft substitutes used for maxillofacial and craniofacial repair: allografts, xenografts, synthetic biomaterials, and tissue‐engineered substitutes. A brief overview of bone tissue engineering evolution including the use of mesenchymal stem cells is exposed, highlighting the first clinical applications of adipose‐derived stem/stromal cells in craniofacial reconstruction. The importance of prevascularization strategies for bone tissue engineering is also discussed, with an emphasis on recent work describing substitutes produced using cell sheet‐based technologies, including the use of thermo‐responsive plates and the self‐assembly approach of tissue engineering. Indeed, considering their entirely cell‐based design, these natural bone‐like substitutes have the potential to closely mimic the osteogenicity, osteoconductivity, osteoinduction, and osseointegration properties of autogenous bone for maxillofacial and craniofacial reconstruction.
Design and Structure–Function Characterization of 3D Printed Synthetic Porous Biomaterials for Tissue Engineering
Authors: Kelly Cambre N. , Miller Andrew T. , Hollister Scott J. , Guldberg Robert E. , Gall Ken
Published: December 2017

3D printing is now adopted for use in a variety of industries and functions. In biomedical engineering, 3D printing has prevailed over more traditional manufacturing methods in tissue engineering due to its high degree of control over both macro‐ and microarchitecture of porous tissue scaffolds. However, with the improved flexibility in design come new challenges in characterizing the structure–function relationships between various architectures and both mechanical and biological properties in an assortment of clinical applications. Presently, the field of tissue engineering lacks a comprehensive body of literature that is capable of drawing meaningful relationships between the designed structure and resulting function of 3D printed porous biomaterial scaffolds. This work first discusses the role of design on 3D printed porous scaffold function and then reviews characterization of these structure–function relationships for 3D printed synthetic metallic, polymeric, and ceramic biomaterials.
2D MoS2 Nanostructures for Biomedical Applications
Authors: Liu Teng , Liu Zhuang
Published: December 2017

MoS2 nanosheets, a typical kind of layered transition metal dichalcogenides with the 2D structure and many unique physical and chemical properties, have attracted a lot of research interests in various fields. Typically, MoS2 nanosheets present similarities to graphene in terms of their large surface area and strong absorbance in near‐infrared region, which in combination with their easily functionalized surface make them promising nanoplatforms in biomedical applications. Herein, the progress of MoS2 nanosheets and their composites in the area of nanomedicine, with the emphasis on their synthesis and modification strategies, their biomedical applications in biosensing, imaging and therapy, as well as evaluations of their in vivo behaviors and toxicology profiles are summarized. Finally, the challenges and opportunities of applying MoS2‐based nanomaterials in the biomedicine areas will be discussed.