bluuebunny/crossref_metadata_2025 huggingface dataset:
Mapping and assessment of urban ecosystem condition and services using integrated index of spatial structure
Authors: Nedkov Stoyan , Zhiyanski Miglena , Dimitrov Stelian , Borisova Bilyana , Popov Anton , Ihtimanski Ivo , Yaneva Rositsa , Nikolov Petar , Bratanova-Doncheva Svetla
Published: December 2017

Urban ecosystems are the areas where built infrastructure covers a large proportion of the land surface but the main source of ecosystem services provision is the green infrastructure. This provision is very much dependent on the particular combination of green spaces such as parks or vegetation belts and paved areas such as buildings and streets. The spatial arrangement of these elements is an important parameter which could be used for the assessment of the ecosystem condition in the urban areas. An integrated index of spatial structure is proposed which incorporates built types and land cover from the Local Climate Zones (LCZ) concept with urban ecosystems' classes developed on the basis of MAES typology. An algorithm has been developed for index generation using an urban ecosystems' database and remote sensing data. The index is used to define vegetation cover in urban ecosystems and assess their condition as a part of the assessment framework. It is also applied in the assessment of several ecosystem services through quantification of ecosystem services' indicators or as an indicator in a complex assessment. The results show that, although most urban ecosystems in Bulgaria are assessed as moderate and good condition, very few of them have very good condition and about 3.5% have very bad condition. The highest scores are defined for urban green areas while the lowest are for transport networks. The use of an integrated index in urban ecosystem services' assessment is represented by examples for global and local climate regulation. The results are used to develop maps of ecosystem services supply capacity for selected cities. The overall analysis indicates that the urban ecosystems in Bulgaria have a moderate to good capacity for local climate regulation and moderate to low capacity for global climate regulation. The integrated index of spatial structure provides an appropriate basis for characterisation and assessment of the urban ecosystems condition and ecosystem services following the requirements of the EU Biodiversity Strategy and the MAES process. The proposed approach enables the internal heterogeneity of the urban ecosystems at national level to be defined, this being one of the main challenges in studying urban ecological systems.
Probabilistic Seismic Hazard Analysis and Synthetic Ground Motion Generation for Seismic Risk Assessment of Structures in the Northeast India
Authors: Ghosh Swarup , Chakraborty Subrata
Published: December 2017

This article outlines the performance-based seismic risk assessment (PBSRA) of structures requiring probabilistic seismic hazard analysis (PSHA) to obtain hazard curves and an evaluation of the demand model by a nonlinear structural response analysis under properly selected ground motion records. Unfortunately, such site-specific information is not readily available for Northeast region of India. The present study focuses on these two aspects to supplement the PBSRA. The estimations of hazard curves are demonstrated by considering the seismicity within 300 km radius around the considered locations and specified exposure period. Due to limited availability of natural records in this region, synthetic accelerograms are generated using stochastic point source models by identifying the most contributing magnitude distance combinations from disaggregation of the PSHA results. The significant variabilities observed in the estimated hazard, synthetic accelerograms and nonlinear building responses in the various locations indicate the need of explicit site-specific analysis for PBRSA of structures in the region.
Optimum Performance of Bridge Isolation System under Parameter Uncertainty
Authors: Roy Bijan Kumar
Published: December 2017

This article deals with the study of optimum performance of isolated bridge systems under stochastic earthquake load considering uncertain system parameters. The conditional stochastic response quantities are obtained in random vibration framework using the state space formulation. Subsequently, with the aid of matrix perturbation theory using first order Taylor series expansion of dynamic response function and its interval extension, the vibration control problem is transformed to appropriate deterministic optimization problems. This requires two separate objective functions correspond to a lower and upper bound optimum solutions. A lead rubber bearing system for isolating a bridge deck from a pier is considered for numerical study to elucidate the optimum performance of isolated bridge deck system. Then a numerical study is performed to observe the effect of parameter uncertainty on the optimization of the isolator parameters and the response reduction efficiency. It is seen that neglecting the effect of system parameter uncertainty may overestimate the system performance.
The Dawn of Paternal HR
Authors: Abdullah Muhammad , Iqbal Salman
Published: December 2017

The purpose of this article is to explore and investigate the effects of paternal HR practices on the employee behavior outcomes. There is dearth of knowledge research on paternal HR practices in Pakistan, its effect on employee outcomes and organizational performance. The authors have applied a system dynamic approach to explore the interactive effects of paternal HR practices on employee behavior. The paternal HR practices effect the employee job quitting intentions. The paternal HR practices improve the employee loyalty and commitment towards the manager and organization. It induces selfless employee behavior, enhances leader identification, increases social exchange, and fosters the trust. Trust and loyalty bonds an employee in psychological relation with an organization and a manager, leading to employee commitment. The better role identification leads to improved employee performance. Nonetheless, the proposed system of paternal HR practices helps the organizations influence employee behavior strategically, which can help reduce employee turnover. The value of this article lies in the understanding gained about the interactive effects of paternal HR practices on employee resignation with the help of system modeling and learning from the simulation outcomes.
Food Security Indicators for Subsistence Farmers Sustainability
Authors: Guma Isdore Paterson , Rwashana Agnes Semwanga , Oyo Benedict
Published: December 2017

Food security concepts are extensively used in households as a measure of welfare, to conceptualise operational usefulness in the design, implementation, and evaluation of policies. Most research is focused on improving food security and sustainability and the patterns still remain tenuous. This article explores food security indicators for sustainability by using system dynamics to understand the interconnectedness of the food security system. This is done by analysing quantitative and qualitative concepts of food security indicators. The simulation result shows dynamics of cropland decreasing with increasing population as they need food, energy and space to survive.
Collaboration in Virtual Worlds
Authors: Nah Fiona Fui-Hoon , Schiller Shu Z. , Mennecke Brian E. , Siau Keng , Eschenbrenner Brenda , Sattayanuwat Parichart
Published: December 2017

Virtual worlds are three-dimensional, computer-generated worlds in which team collaboration can be facilitated through the use of shared virtual space and mediated using avatars. This article examines the effect of task complexity on team collaboration. A puzzle game in Second Life was used as the collaborative task and task complexity was manipulated by varying the number of pieces in the puzzle. The hypotheses are that task complexity influences team trust, and team trust influences team process satisfaction in virtual team collaboration. The experimental results indicate that task complexity has significant effects on team trust and team process satisfaction, and team trust fully mediates the relationship between task complexity and team process satisfaction.
IL-3 Differentially Regulates Membrane and Soluble RANKL in Osteoblasts through Metalloproteases and the JAK2/STAT5 Pathway and Improves the RANKL/OPG Ratio in Adult Mice
Authors: Singh Kanupriya , Piprode Vikrant , Mhaske Suhas T. , Barhanpurkar-Naik Amruta , Wani Mohan R.
Published: December 2017

Bone remodeling comprises balanced activities between osteoclasts and osteoblasts, which is regulated by various factors, including hormones and cytokines. We previously reported that IL-3 inhibits osteoclast differentiation and pathological bone loss. IL-3 also enhances osteoblast differentiation and bone formation from mesenchymal stem cells. However, the role of IL-3 in regulation of osteoblast–osteoclast interactions and underlying mechanisms is not yet delineated. In this study, we investigated the role of IL-3 on the regulation of osteoblast-specific molecules, receptor activator of NF-κB ligand (RANKL), and osteoprotegerin (OPG) that modulate bone homeostasis. We found that IL-3 increases RANKL expression at both the transcriptional and translational levels, and it showed no effect on OPG expression in calvarial osteoblasts. The increased RANKL expression by IL-3 induces mononuclear osteoclasts; however, it does not induce multinuclear osteoclasts. Interestingly, IL-3 decreases soluble RANKL by reducing ectodomain shedding of membrane RANKL through downregulation of metalloproteases mainly a disintegrin and metalloproteinase (ADAM)10, ADAM17, ADAM19, and MMP3. Moreover, IL-3 increases membrane RANKL by activating the JAK2/STAT5 pathway. Furthermore, IL-3 enhances RANKL expression in mesenchymal stem cells of wild-type mice but not in STAT5a knockout mice. Interestingly, IL-3 restores RANKL expression in adult mice by enhancing bone-specific RANKL and decreasing serum RANKL. Furthermore, IL-3 increases the serum OPG level in adult mice. Thus, our results reveal, to our knowledge for the first time, that IL-3 differentially regulates two functional forms of RANKL through metalloproteases and the JAK2/STAT5 pathway, and it helps in restoring the decreased RANKL/OPG ratio in adult mice. Notably, our studies indicate the novel role of IL-3 in regulating bone homeostasis in important skeletal disorders.
Terminal chords in connected chord diagrams
Authors: Courtiel Julien , Yeats Karen
Published: December 2017

Rooted connected chord diagrams form a nice class of combinatorial objects. Recently they were shown to index solutions to certain Dyson–Schwinger equations in quantum field theory. Key to this indexing role are certain special chords which are called terminal chords. Terminal chords provide a number of combinatorially interesting parameters on rooted connected chord diagrams which have not been studied previously. Understanding these parameters better has implications for quantum field theory.

Specically, we show that the distributions of the number of terminal chords and the number of adjacent terminal chords are asymptotically Gaussian with logarithmic means, and we prove that the average index of the first terminal chord is

2n/3

. Furthermore, we obtain a method to determine any next-to

^i

leading log expansion of the solution to these Dyson–Schwinger equations, and have asymptotic information about the coecients of the log expansions.
Научное наследие Л. Д. Фаддеева. Обзор работ
Authors: Takhtadzhyan Leon Armenovich , Alekseev Anton Yur'evich , Aref'eva Irina Yaroslavna , Semenov-Tian-Shansky Michael Arsen'evich , Sklyanin Evgeny Konstantinovich , Smirnov Fedor Aleksandrovich , Shatashvili Samson Lulievich
Published: December 2017

Обзор написан учениками Л. Д. Фаддеева под редакцией Л. А. Тахтаджяна. Разделы статьи написаны: разделы 1.1, 1.2, 2-4 и 6 - Л. А. Тахтаджяном, разделы 1.3 и 1.4 - Ф. А. Смирновым, разделы 5.1 и 5.2 - Е. К. Скляниным, разделы 5.3-5.6 - Е. К. Скляниным, Ф. А. Смирновым и Л. А. Тахтаджяном, раздел 7.1 - М. А. Семеновым-Тян-Шанским, разделы 7.2-7.6 - Л. А. Тахтаджяном и С. Л. Шаташвили, раздел 7.7 - А. Ю. Алексеевым и С. Л. Шаташвили, раздел 8 - И. Я. Арефьевой.
Библиография: 130 названий.
Динамическая магнитная восприимчивость в спин-фермионной модели купратных сверхпроводников
Authors: Val'kov Valerii Vladimirovich , Dzebisashvili Dmitrii Mikhailovich
Published: December 2017

В рамках $SU(2)$-инвариантной спин-фермионной модели электронного строения CuO$_2$-плоскости оксидов меди методом диаграммных техник для спиновых и фермиевских операторов получено точное представление для мацубаровской функции Грина подсистемы локализованных спинов $D_\perp(k,i\omega_m)$. Это представление включает массовый оператор Ларкина $\Sigma_{\mathrm L}(k,i\omega_m)$, силовой $P(k,i\omega_m)$ и поляризационный $\Pi(k,i\omega_m)$ операторы. Вычисление в однопетлевом приближении массового и силового операторов для гейзенберговской системы спинов, находящейся в состоянии квантовой спиновой жидкости, позволило в явном виде записать функцию Грина $D_\perp(k,i\omega_m)$ и установить соответствие с результатом Шимахары и Такады. Существенным моментом развитого подхода явился учет спин-поляронной природы фермиевских квазичастиц спин-фермионной модели при нахождении вкладов кислородных дырок в спиновую восприимчивость через поляризационный оператор $\Pi(k,i\omega_m)$.
$q$-Деформированные $su(1, 1)$-когерентные состояния Барута-Жирарделло и состояния кота Шредингера
Authors: Zhao Yuefeng , Zeng Yan , Liu Honggang , Song Qi , Wang Gangcheng , Xue Kang
Published: December 2017

Состояния кота Шредингера определены как суперпозиции $q$-деформированных $su(1,1)$-когерентных состояний Барута-Жирарделло с регулируемым углом $\varphi$ в $q$-деформированном пространстве Фока. Изучены статистические свойства $q$-деформированных $su(1,1)$-когерентных состояний Барута-Жирарделло и квантовых состояний кота Шредингера. Как оказалось, в случае $q$-деформированных $su(1,1)$-когерентных состояний Барута-Жирарделло статистические свойства фотонов всегда являются субпуассоновскими. В случае состояний кота Шредингера при $\varphi=0,\pi/2,\pi$ статистические свойства фотонов всегда являются субпуассоновскими, если $\varphi=\pi/2$, а в других ситуациях их трудно охарактеризовать, поскольку они зависят от параметров $q$ и $k$. Более того, найдены некоторые интересные свойства состояний кота Шредингера в пределе при $|z|\rightarrow0$, где $z$ - параметр этих состояний. Также сделан вывод, что статистические свойства фотонов являются субпуассоновскими в недеформированном случае, когда $\pi/2\leq \varphi\leq3\pi/2$.
Процесс установления системы плоских волн на ледовом покрове над диполем, равномерно движущимся в толще идеальной жидкости
Authors: Il'ichev Andrej Teimurazovich , Savin Aleksandr Sergeevich
Published: December 2017

Рассматривается плоская задача об эволюции возмущений ледового покрова диполем, начинающим равномерное и прямолинейное движение по горизонтали в толще изначально неподвижной жидкости. При помощи асимптотического фурье-анализа показано, что для сверхкритических скоростей формируются волны двух типов на поверхности раздела вода-лед. Описан процесс установления этих волн в процессе движения диполя. Жидкость предполагается идеальной и несжимаемой, а ее движение - потенциальным. Ледовый покров моделируется пластиной Кирхгоффа-Лява.
О возможности описания неабелевых массивных калибровочных полей в рамках перенормируемой теории
Authors: Slavnov Andrei Alekseevich
Published: December 2017

Предложена перенормируемая теория массивных неабелевых калибровочных полей, которая не требует существования наблюдаемых скалярных полей.
Квазилинейная формулировка $\sigma$-модели пространства флагов
Authors: Bykov Dmitrii Vladimirovich
Published: December 2017

$\sigma$-Модели пространства флагов, обладающие представлением нулевой кривизны, формулируются в виде теории линейных "полей материи", взаимодействующих со вспомогательными калибровочными полями.
El proyecto cultural: hacia una revisión del concepto en la perspectiva de un marco referencial
Authors: Figueroa Miranda Gustavo Alejandro
Published: December 2017

La metodología de proyectos constituye en la actualidad una de las herramientas técnicas de actuación más utilizadas en Gestión Cultural, en el presente artículo se propone una revisión del concepto de proyecto cultural intentando investigar más allá de sus ventajas funcionales. A partir de un análisis de algunos de los problemas y críticas que cuestionan la metodología en algún sentido, se postula que es posible un estudio desde una perspectiva de comprensión más adecuada, completa y profunda del concepto. La perspectiva que se propone es la Gestión Cultural entendida como una nueva manera de comprender y trabajar en torno a los problemas del sector cultural en función del desarrollo, en este sentido, la Gestión Cultural puede entenderse como un marco referencial anterior y más amplio que puede revelar dimensiones de comprensión que van más allá de lo puramente técnico o instrumental, que es como en general se tiende a pensar el concepto de proyecto.
Las instituciones frente a la declaratoria de la pirekua, canto tradicional de los p’urhépecha
Authors: Flores Mercado Georgina
Published: December 2017

El presente artículo analiza el proceso de la patrimonialización de la pirekua, canto tradicional del pueblo indígena p’urhépecha (México). La declaración de la pirekua, Patrimonio Cultural Inmaterial de la Humanidad por la UNESCO, fue una declaratoria controvertida en tanto que las comunidades p’urhépecha no fueron ni informadas ni consultadas para ello, lo que devino en un conflicto. Para comprender este proceso de patrimonialización identificamos a distintos agentes sociales, así como sus posiciones frente a este proceso. En este sentido nos focalizamos en analizar la actuación de las instituciones gubernamentales mexicanas tanto de nivel federal como estatal. Utilizando los conceptos de la teoría de campo de Pierre Bourdieu, realizamos un análisis discursivo que nos permitió tanto dar cuenta de los discursos y posiciones de los funcionarios como de la producción y reproducción de las relaciones de poder y/o dominación en el campo patrimonial mexicano.
Laparoscopic Ovarian Drilling in Clomiphene-resistant Polycystic Ovarian Syndrome Women: A Retrospective Analysis
Authors: Kamath Mohan S , Thomas Sumi , Vithayathil Vivek P , Chandy Achamma , Aleyamma Thaiparambil K
Published: December 2017

Introduction

Ovulation induction in women with polycystic ovarian syndrome (PCOS) can be carried out with drugs, such as clomiphene citrate (CC), which remains the first-line treatment option, and surgery, such as laparoscopic ovarian drilling (LOD), which is usually recommended as one of the second-line treatment options. Laparoscopic ovarian drilling may avoid or reduce the need for gonadotropins and at the same time reduce ovarian hyperstimulation syndrome (OHSS) and multiple pregnancy.

Aim

We aimed to evaluate the effectiveness of LOD in clomiphene-resistant women and to identify the clinical factors that might predict its success.

Study design

Retrospective analysis in a tertiary level infertility unit.

Materials and methods

All CC-resistant PCOS women who underwent LOD over a 10-year period were included. Polycystic ovarian syndrome was defined as per the Rotterdam criteria. The follow-up period was up to 3 years post-LOD. Outcomes, such as onset of regular cycles, spontaneous pregnancies, and live births were recorded.

Results

A total of 59 PCOS women who underwent LOD and were available for follow-up were included in the study. Majority of the patients were less than 30 years of age with a body mass index (BMI) > 24 kg/m2. Out of those, 12 conceived (20.3%) spontaneously and 14 (23.7%) had regular menstrual cycles after the procedure. The live birth rate was 16.9% (10/59). We did not find any association of clinical factors, such as age, BMI, type of infertility, and history of irregular cycles with LOD success.

Conclusion

Laparoscopic ovarian drilling can be offered as a treatment option in select group of CC-resistant women with reasonable success. Post-LOD, for those who do not have resumption of regular cycles, alternate method of ovulation induction can be initiated.

How to cite this article

Thomas S, Vithayathil VP, Chandy A, Aleyamma TK, Kamath MS. Laparoscopic Ovarian Drilling in Clomiphene-resistant Polycystic Ovarian Syndrome Women: A Retrospective Analysis. Int J Infertil Fetal Med 2017;8(3):93-96.
Study on Infertility—Etiology, Medication Therapy Management, and Outcomes at a Tertiary Care Hospital
Authors: Khanuja Purvi K , Sunny Juby A , Pawar Sunita B
Published: December 2017

Aim

The aim of the article is to study infertility—etiology, medication therapy management, and outcomes in a tertiary care hospital.

Objectives

The purpose of this study was to compare the outcomes of standard aetiology wise treatment protocols of infertility and the various causes which may be a contributing factor to infertility.

Materials and methods

A prospective observational study was conducted for 6 months at a tertiary care hospital. Couples diagnosed with infertility, aged 18 to 49 years were enrolled in the study. Details like couple's sociodemographic data, etiology, risk factors associated with infertility, management with current medications, procedures, and outcomes were documented using predesigned infertility proforma.

Results

Females had an age group of 19 to 38 years with an average age and standard deviation (SD) of 25.64 ± 4.07 years, whereas male patients had an age of 24 to 43 years with a mean age and SD of 30.59 ± 4.17 years. Primary infertility was 59.13% and secondary infertility 40.86%. In women with infertility, ovulatory disorders were the chief cause, followed by unexplained factor, uterine tubal, and more than one cause, whereas in males semen abnormalities were the major cause of both primary and secondary infertility, followed by unexplained, anatomical, more than one cause. Medical therapy involving drugs like clomiphene, gonadotropins, and a combination was administered to females. Males received lycopene, L-carnitine, ubidecarenone, zinc, and astaxanthin. Intrauterine insemination (IUI) was performed in 28 patients. From the available data of 100 couples undergoing management for infertility in the 6 months study period, 19 patients conceived, i.e., 19% showed conception.

Conclusion

The present study shows etiological and pathological causes of infertility. The study highlights positive results with standard treatments.

Clinical significance

To identify hidden social, medical, pathological, and other confounding causes leading to infertility.

How to cite this article

Khanuja PK, Sunny JA, Pawar SB, Nimbargi V. Study on Infertility—Etiology, Medication Therapy Management, and Outcomes at a Tertiary Care Hospital. Int J Infertil Fetal Med 2017;8(3):106-112.
Curriculum-Level Strategies That U.S. Occupational Therapy Programs Use to Address Occupation: A Qualitative Study
Authors: Hooper Barb , Krishnagiri Sheama , Price Pollie , Taff Steven D. , Bilics Andrea
Published: December 2017

OBJECTIVE. This study’s objective was to describe curriculum-level strategies used to convey occupation to occupational therapy students.

METHOD. The study used a descriptive qualitative research design. Fifteen occupational therapy and 10 occupational therapy assistant programs participated in interviews, submitted curriculum artifacts such as syllabi and assignments, and recorded teaching sessions. Data were coded both inductively and deductively and then categorized into themes.

RESULTS. Occupational therapy programs designed strategies on two levels of the curriculum, infrastructure and implementation, to convey knowledge of occupation to students. The degree to which strategies explicitly highlighted occupation and steered instruction fluctuated depending on how differentiated occupation was from other concepts and skills.

CONCLUSION. Two arguments are presented about the degree to which occupation needs to be infused in all curricular elements. To guide curriculum design, it is critical for educators to discuss beliefs about how ubiquitous occupation is in a curriculum and whether curricular elements portray occupation to the extent preferred.
Investigation of the Relationship Between Sensory Processing and Motor Development in Preterm Infants
Authors: Celik Halil Ibrahim , Elbasan Bulent , Gucuyener Kivilcim , Kayihan Hulya , Huri Meral
Published: December 2017

OBJECTIVE. The aim of this study was to analyze the correlation between sensory processing and motor development in preterm infants.

METHOD. We included 30 preterm and 30 term infants with corrected and chronological ages between 10 and 12 mo. We used the Test of Sensory Functions in Infants to evaluate sensory processing and the Alberta Infant Motor Scale to evaluate motor development.

RESULTS. The Spearman correlation test indicated a strong positive relationship between sensory processing and motor development in preterm infants (r = .63, p < .001).

CONCLUSION. Given the relationship between sensory processing and motor development in the preterm group, the evaluation of sensory processing and motor development in preterm infants was considered necessary for the effective implementation of physiotherapy assessment and interventions.
Sky radiance at a coastline and effects of land and ocean reflectivities
Authors: Kreuter Axel , Blumthaler Mario , Tiefengraber Martin , Kift Richard , Webb Ann R.
Published: December 2017

Abstract. We present a unique case study of the spectral sky radiance distribution above a coastline. Results are shown from a measurement campaign in Italy involving three diode array spectroradiometers which are compared to 3-D model simulations from the Monte Carlo model MYSTIC. On the coast, the surrounding is split into two regions, a diffusely reflecting land surface and a water surface which features a highly anisotropic reflectance function. The reflectivities and hence the resulting radiances are a nontrivial function of solar zenith and azimuth angle and wavelength. We show that for low solar zenith angles (SZAs) around noon, the higher land albedo causes the sky radiance at 20° above the horizon to increase by 50 % in the near infrared at 850 nm for viewing directions towards the land with respect to the ocean. Comparing morning and afternoon radiances highlights the effect of the ocean's sun glint at high SZA, which contributes around 10 % to the measured radiance ratios. The model simulations generally agree with the measurements to better than 10 %. We investigate the individual effects of model input parameters representing land and ocean albedo and aerosols. Different land and ocean bi-directional reflectance functions (BRDFs) do not generally improve the model agreement. However, consideration of the uncertainties in the diurnal variation of aerosol optical depth can explain the remaining discrepancies between measurements and model. We further investigate the anisotropy effect of the ocean BRDF which is featured in the zenith radiances. Again, the uncertainty of the aerosol loading is dominant and obscures the modelled sun glint effect of 7 % at 650 nm. Finally, we show that the effect on the zenith radiance is restricted to a few kilometres from the coastline by model simulations along a perpendicular transect and by comparing the radiances at the coast to those measured at a site 15 km inland. Our findings are relevant to, for example, ground-based remote sensing of aerosol characteristics, since a common technique is based on sky radiance measurements along the solar almucantar.
Cloud heterogeneity effects on cloud and aerosol above cloud properties retrieved from simulated total and polarized reflectances
Authors: Cornet Céline , C-Labonnote Laurent , Szczap Frédéric , Deaconu Lucia , Waquet Fabien , Parol Frédéric , Vanbauce Claudine , Thieuleux François , Riédi Jérôme
Published: December 2017

Abstract. Simulations of total and polarized cloud reflectance angular signatures such as the ones measured by the multi-angular and polarized radiometer POLDER3/PARASOL are used to evaluate cloud heterogeneity effects on cloud parameter retrievals. Effects on optical thickness, cloud albedo, effective radius and variance of the cloud droplet size distribution and aerosol above cloud optical thickness are analyzed. Three different clouds having the same mean optical thicknesses were generated: the first one with a flat top, the second one with a bumpy top and the last one with a fractional cloud cover. At small scale (50 m), for oblique solar incidence, the illumination effects lead to higher total but also polarized reflectances. The polarized reflectances even reach values that cannot be predicted by the 1D homogeneous cloud assumption. At the POLDER scale (7 km × 7 km), the angular signature is modified by a combination of the plane-parallel bias and the shadowing and illumination effects. In order to quantify effects of cloud heterogeneity on operational products, we ran the POLDER operational algorithms on the simulated reflectances to retrieve the cloud optical thickness and albedo. Results show that the cloud optical thickness is greatly affected: biases can reach up to −70 %, −50 % or +40 % for backward, nadir and forward viewing directions respectively. Concerning the cloud albedo, the errors are smaller, between −4.7 % for solar incidence angle of 20° and up to about 8 % for solar incidence angle of 60°. We also tested the heterogeneity effects on new algorithms that allow retrieving cloud droplet size distribution and cloud top pressures and also aerosol above clouds. Contrarily to the bi-spectral method, the retrieved cloud droplet size parameters are not significantly affected by the cloud heterogeneity, which proves to be a great advantage of using polarized measurements. However the cloud top pressure obtained from molecular scattering in the forward direction can be biased up to 120 hPa (around 1 km). Concerning the aerosol optical thickness (AOT) above cloud, the results are different depending on the available angular information. Above the fractional cloud, when only side scattering angles are available, the AOT can be underestimated because of the plane-parallel bias. For solar zenith angle of 60°, on contrary, it is overestimated because the polarized reflectances are increased in forward directions.
Improving global paleogeography since the late Paleozoic using paleobiology
Authors: Cao Wenchao , Zahirovic Sabin , Flament Nicolas , Williams Simon , Golonka Jan , Müller R. Dietmar
Published: December 2017

Abstract. Paleogeographic reconstructions are important to understand Earth's tectonic evolution, past eustatic and regional sea level change, paleoclimate and ocean circulation, deep Earth resources and to constrain and interpret the dynamic topography predicted by mantle convection models. Global paleogeographic maps have been compiled and published, but they are generally presented as static maps with varying map projections, different time intervals represented by the maps and different plate motion models that underlie the paleogeographic reconstructions. This makes it difficult to convert the maps into a digital form and link them to alternative digital plate tectonic reconstructions. To address this limitation, we develop a workflow to restore global paleogeographic maps to their present-day coordinates and enable them to be linked to a different tectonic reconstruction. We use marine fossil collections from the Paleobiology Database to identify inconsistencies between their indicative paleoenvironments and published paleogeographic maps, and revise the locations of inferred paleo-coastlines that represent the estimated maximum transgression surfaces by resolving these inconsistencies. As a result, the consistency ratio between the paleogeography and the paleoenvironments indicated by the marine fossil collections is increased from an average of 75 % to nearly full consistency (100 %). The paleogeography in the main regions of North America, South America, Europe and Africa is significantly revised, especially in the Late Carboniferous, Middle Permian, Triassic, Jurassic, Late Cretaceous and most of the Cenozoic. The global flooded continental areas since the Early Devonian calculated from the revised paleogeography in this study are generally consistent with results derived from other paleoenvironment and paleo-lithofacies data and with the strontium isotope record in marine carbonates. We also estimate the terrestrial areal change over time associated with transferring reconstruction, filling gaps and modifying the paleogeographic geometries based on the paleobiology test. This indicates that the variation of the underlying plate reconstruction is the main factor that contributes to the terrestrial areal change, and the effect of revising paleogeographic geometries based on paleobiology is secondary.
Modeling impacts of climate change and grazing effects on plant biomass and soil organic carbon in the Qinghai–Tibetan grasslands
Authors: Zhang Wenjuan , Zhang Feng , Qi Jiaguo , Hou Fujiang
Published: December 2017

Abstract. The Qinghai Province supports over 40 % of the human population of the Qinghai–Tibetan Plateau (QTP) but occupies about 29 % of its land area, and thus it plays an important role in the plateau. The dominant land cover is grassland, which has been severely degraded over the last decade due to a combination of increased human activities and climate change. Numerous studies indicate that the plateau is sensitive to recent global climate change, but the drivers and consequences of grassland ecosystem change are controversial, especially the effects of climate change and grazing patterns on the grassland biomass and soil organic carbon (SOC) storage in this region. In this study, we used the DeNitrification-DeComposition (DNDC) model and two climate change scenarios (representative concentration pathways: RCP4.5 and RCP8.5) to understand how the grassland biomass and SOC pools might respond to different grazing intensities under future climate change scenarios. More than 1400 grassland biomass sampling points and 46 SOC points were used to validate the simulated results. The simulated above-ground biomass and SOC concentrations were in good agreement with the measured data (R2 0.71 and 0.73 for above-ground biomass and SOC, respectively). The results showed that climate change may be the major factor that leads to fluctuations in the grassland biomass and SOC, and it explained 26.4 and 47.7 % of biomass and SOC variation, respectively. Meanwhile, the grazing intensity explained 6.4 and 2.3 % variation in biomass and SOC, respectively. The project average biomass and SOC between 2015 and 2044 was significantly smaller than past 30 years (1985–2014), and it was 191.17 g C m−2, 63.44 g C kg−1 and 183.62 g C m−2, 63.37 g C kg−1 for biomass and SOC under RCP4.5 and RCP8.5, respectively. The RCP8.5 showed the more negative effect on the biomass and SOC compared with RCP4.5. Grazing intensity had a negative relationship with biomass and positive relationship with SOC. Compared with the baseline, the biomass and SOC changed by 12.56 and −0.19 % for G0, 7.23 and 0.23 for G−50, and −5.17 and 1.19 % for G+50. In the future, more human activity and management practices should be coupled into the model simulation.
Three distinct Holocene intervals of stalagmite deposition and nondeposition revealed in NW Madagascar, and their paleoclimate implications
Authors: Voarintsoa Ny Riavo Gilbertinie , Railsback Loren Bruce , Brook George Albert , Wang Lixin , Kathayat Gayatri , Cheng Hai , Li Xianglei , Edwards Richard Lawrence , Rakotondrazafy Amos Fety Michel , Madison Razanatseheno Marie Olga
Published: December 2017

Abstract. Petrographic features, mineralogy, and stable isotopes from two stalagmites, ANJB-2 and MAJ-5, respectively from Anjohibe and Anjokipoty caves, allow distinction of three intervals of the Holocene in NW Madagascar. The Malagasy early Holocene (between ca. 9.8 and 7.8 ka) and late Holocene (after ca. 1.6 ka) intervals (MEHI and MLHI, respectively) record evidence of stalagmite deposition. The Malagasy middle Holocene interval (MMHI, between ca. 7.8 and 1.6 ka) is marked by a depositional hiatus of ca. 6500 years. Deposition of these stalagmites indicates that the two caves were sufficiently supplied with water to allow stalagmite formation. This suggests that the MEHI and MLHI intervals may have been comparatively wet in NW Madagascar. In contrast, the long-term depositional hiatus during the MMHI implies it was relatively drier than the MEHI and the MLHI. The alternating wet–dry–wet conditions during the Holocene may have been linked to the long-term migrations of the Intertropical Convergence Zone (ITCZ). When the ITCZ's mean position is farther south, NW Madagascar experiences wetter conditions, such as during the MEHI and MLHI, and when it moves north, NW Madagascar climate becomes drier, such as during the MMHI. A similar wet–dry–wet succession during the Holocene has been reported in neighboring locations, such as southeastern Africa. Beyond these three subdivisions, the records also suggest wet conditions around the cold 8.2 ka event, suggesting a causal relationship. However, additional Southern Hemisphere high-resolution data will be needed to confirm this.
A JavaScript API for the Ice Sheet System Model (ISSM) 4.11: towards an online interactive model for the cryosphere community
Authors: Larour Eric , Cheng Daniel , Perez Gilberto , Quinn Justin , Morlighem Mathieu , Duong Bao , Nguyen Lan , Petrie Kit , Harounian Silva , Halkides Daria , Hayes Wayne
Published: December 2017

Abstract. Earth system models (ESMs) are becoming increasingly complex, requiring extensive knowledge and experience to deploy and use in an efficient manner. They run on high-performance architectures that are significantly different from the everyday environments that scientists use to pre- and post-process results (i.e., MATLAB, Python). This results in models that are hard to use for non-specialists and are increasingly specific in their application. It also makes them relatively inaccessible to the wider science community, not to mention to the general public. Here, we present a new software/model paradigm that attempts to bridge the gap between the science community and the complexity of ESMs by developing a new JavaScript application program interface (API) for the Ice Sheet System Model (ISSM). The aforementioned API allows cryosphere scientists to run ISSM on the client side of a web page within the JavaScript environment. When combined with a web server running ISSM (using a Python API), it enables the serving of ISSM computations in an easy and straightforward way. The deep integration and similarities between all the APIs in ISSM (MATLAB, Python, and now JavaScript) significantly shortens and simplifies the turnaround of state-of-the-art science runs and their use by the larger community. We demonstrate our approach via a new Virtual Earth System Laboratory (VESL) website (http://vesl.jpl.nasa.gov, VESL(2017)).
Impact of asymmetric uncertainties in ice sheet dynamics on regional sea level projections
Authors: de Winter Renske C. , Reerink Thomas J. , Slangen Aimée B. A. , de Vries Hylke , Edwards Tamsin , van de Wal Roderik S. W.
Published: December 2017

Abstract. Currently a paradigm shift is made from global averaged to spatially variable sea level change (SLC) projections. Traditionally, the contribution from ice sheet mass loss to SLC is considered to be symmetrically distributed. However, several assessments suggest that the probability distribution of dynamical ice sheet mass loss is asymmetrically distributed towards higher SLC values. Here we show how asymmetric probability distributions of dynamical ice sheet mass loss impact the high-end uncertainties of regional SLC projections across the globe. For this purpose we use distributions of dynamical ice sheet mass loss presented by Church et al. (2013), De Vries and Van de Wal (2015) and Ritz et al. (2015). The global average median can be 0.18 m higher compared to symmetric distributions based on IPCC-AR5, but the change in the global average 95th percentile SLC is considerably larger with a shift of 0.32 m. Locally the 90th, 95th and 97.5th SLC percentiles exceed +1.4, +1.6 and +1.8 m. The high-end percentiles of SLC projections are highly sensitive to the precise shape of the probability distributions of dynamical ice sheet mass loss. The shift towards higher values is of importance for coastal safety strategies as they are based on the high-end percentiles of projections.
Dynamical properties and extremes of Northern Hemisphere climate fields over the past 60 years
Authors: Faranda Davide , Messori Gabriele , Alvarez-Castro M. Carmen , Yiou Pascal
Published: December 2017

Abstract. Atmospheric dynamics are described by a set of partial differential equations yielding an infinite-dimensional phase space. However, the actual trajectories followed by the system appear to be constrained to a finite-dimensional phase space, i.e. a strange attractor. The dynamical properties of this attractor are difficult to determine due to the complex nature of atmospheric motions. A first step to simplify the problem is to focus on observables which affect – or are linked to phenomena which affect – human welfare and activities, such as sea-level pressure, 2 m temperature, and precipitation frequency. We make use of recent advances in dynamical systems theory to estimate two instantaneous dynamical properties of the above fields for the Northern Hemisphere: local dimension and persistence. We then use these metrics to characterize the seasonality of the different fields and their interplay. We further analyse the large-scale anomaly patterns corresponding to phase-space extremes – namely time steps at which the fields display extremes in their instantaneous dynamical properties. The analysis is based on the NCEP/NCAR reanalysis data, over the period 1948–2013. The results show that (i) despite the high dimensionality of atmospheric dynamics, the Northern Hemisphere sea-level pressure and temperature fields can on average be described by roughly 20 degrees of freedom; (ii) the precipitation field has a higher dimensionality; and (iii) the seasonal forcing modulates the variability of the dynamical indicators and affects the occurrence of phase-space extremes. We further identify a number of robust correlations between the dynamical properties of the different variables.
Submesoscale CO2 variability across an upwelling front off Peru
Authors: Köhn Eike E. , Thomsen Sören , Arévalo-Martínez Damian L. , Kanzow Torsten
Published: December 2017

Abstract. As a major source for atmospheric CO2, the Peruvian upwelling region exhibits strong variability in surface fCO2 on short spatial and temporal scales. Understanding the physical processes driving the strong variability is of fundamental importance for constraining the effect of marine emissions from upwelling regions on the global CO2 budget. In this study, a frontal decay on length scales of 𝒪(10 km) was observed off the Peruvian coast following a pronounced decrease in down-frontal (equatorward) wind speed with a time lag of 9 h. Simultaneously, the sea-to-air flux of CO2 on the inshore (cold) side of the front dropped from up to 80 to 10 mmol m−2 day−1, while the offshore (warm) side of the front was constantly outgassing at a rate of 10–20 mmol m−2 day−1. Based on repeated ship transects the decay of the front was observed to occur in two phases. The first phase was characterized by a development of coherent surface temperature anomalies which gained in amplitude over 6–9 h. The second phase was characterized by a disappearance of the surface temperature front within 6 h. Submesoscale mixed-layer instabilities were present but seem too slow to completely remove the temperature gradient in this short time period. Dynamics such as a pressure-driven gravity current appear to be a likely mechanism behind the evolution of the front.
Dispositivos institucionales y gestión del fracaso escolar: las paradojas de la atención a la diversidad en la ESO
Authors: Rujas Martínez-Novillo Javier
Published: December 2017

Este artículo analiza, a partir de un trabajo etnográfico, uno de los principales modos de gestión del “fracaso escolar” en la enseñanza secundaria obligatoria: los dispositivos institucionales conocidos como “medidas de atención a la diversidad” (MAD). Analizando la lógica práctica de estos programas en un contexto concreto, muestra cómo se construye a los alumnos para cada dispositivo en las prácticas de clasificación y asignación a estas medidas, cómo estas formas de clasificación afectan a las expectativas y a las prácticas pedagógicas de los docentes, y cómo las MAD se encuentran atravesadas en su organización pedagógica por diversas tensiones y ambivalencias. Estos dispositivos han modificado la estructura de la educación obligatoria y los procesos de selección escolar, afectando a la construcción de los juicios escolares, las jerarquías de alumnos y las trayectorias escolares de los estudiantes.
"Big Data", saber-poder y pastoreo digital: sobre el fundamento mitológico de la autoridad
Authors: Cigüela Sola Javier
Published: December 2017

Partiendo del intenso impacto que está teniendo el big data y el resto de tecnologías conexas en nuestra existencia personal y social, el presente artículo busca, en primer lugar, realizar una aproximación a la naturaleza del conocimiento que los datos masivos generan desde el concepto foucaultiano de saber-poder, como también desentrañar el modo en que dicho conocimiento es utilizado para legitimar decisiones que se toman en la incertidumbre. En segundo lugar, intentará analizar qué novedad supone dicho saber en relación a su más inmediato precedente: la estadística y, por último, tendrá como fin examinar el tipo de poder que surge de dicho saber, en relación especialmente con las ideas, de nuevo en la estela de Michel Foucault (1926-1984), acerca del poder pastoral y la conducción a través de la verdad confesada.
“Shadowy Objects in Test Tubes”: The Ethics of Grievance in Kazuo Ishiguro'sNever Let Me Go
Authors: Schwetman John David
Published: December 2017

Every community demands sacrifices from individuals within it, and sometimes such sacrifices can be extreme. To experience harm related to this sort of sacrifice is to be in a state of grievance. Kazuo Ishiguro's 2005 novel Never Let Me Go offers readers a compelling fictional account of severe grievance experienced by its narrator-protagonist and other clones destined to die young when donating their organs to non-clone, or “normal,” members of their community. By presenting radically aggrieved clones as visibly indistinguishable from the “normals,” Ishiguro dramatically challenges traditional understandings of the state of grievance and compels readers to re-examine their own reactions when confronting the spectacle of grievance.
“A Good and Necessary Thing”: Genre and Justice in Octavia Butler'sBloodchild and Other Stories
Authors: Humann Heather Duerre
Published: December 2017

Widely recognized as a science fiction writer, and one of a number of prominent black science fiction writers publishing in English, Octavia Butler's “work needs to be understood within the context of the traditions of the genre” of science fiction, a point Patricia Melzer makes in her book, Alien Constructions: Science Fiction and Feminist Thought. Discussing Octavia Butler's fiction and its genre, however, means going beyond simply using the term science fiction to describe the many literary works she wrote over her prolific and decades-long career.