bluuebunny/crossref_metadata_2025_split huggingface dataset:
A three-dimensional-model inversion of methyl chloroform to constrain the atmospheric oxidative capacity
Authors: Naus Stijn , Montzka Stephen A. , Patra Prabir K. , Krol Maarten C. 
Published: March 2021

Abstract. Variations in the atmospheric oxidative capacity, largely determined by variations in the hydroxyl radical (OH), form a key uncertainty in many greenhouse and other pollutant budgets, such as that of methane (CH4). Methyl chloroform (MCF) is an often-adopted tracer to indirectly put observational constraints on large-scale variations in OH. We investigated the budget of MCF in a 4DVAR inversion using the atmospheric transport model TM5, for the period 1998–2018, with the objective to derive information on large-scale, interannual variations in atmospheric OH concentrations. While our main inversion did not fully converge, we did derive interannual variations in the global oxidation of MCF that bring simulated mole fractions of MCF within 1 %–2 % of the assimilated observations from the NOAA-GMD surface network at most sites. Additionally, the posterior simulations better reproduce aircraft observations used for independent validation compared to the prior simulations. The derived OH variations showed robustness with respect to the prior MCF emissions and the prior OH distribution over the 1998 to 2008 period. Although we find a rapid 8 % increase in global mean OH concentrations between 2010 and 2012 that quickly declines afterwards, the derived interannual variations were typically small (< 3 %/yr), with no significant long-term trend in global mean OH concentrations. The inverse system found strong adjustments to the latitudinal distribution of OH, relative to widely used prior distributions, with systematic increases in tropical and decreases in extra-tropical OH concentrations (both up to 30 %). These spatial adjustments were driven by intrahemispheric biases in simulated MCF mole fractions, which have not been identified in previous studies. Given the large amplitude of these adjustments, which exceeds spread between literature estimates, and a residual bias in the MCF intrahemispheric gradients, we suggest a reversal in the extratropical ocean sink of MCF in response to declining atmospheric MCF abundance (as hypothesized in Wennberg et al., 2004). This ocean source provides a more realistic explanation for the biases, possibly complementary to adjustments in the OH distribution. We identified significant added value in the use of a 3D transport model, since it implicitly accounts for variable transport and optimizes the observed spatial gradients of MCF, which is not possible in simpler models. However, we also found a trade-off in computational expense and convergence problems. Despite these convergence problems, the derived OH variations do result in an improved match with MCF observations relative to an interannually repeating prior for OH. Therefore, we consider that variations in OH derived from MCF inversions with 3D models can add value to budget studies of long-lived gases like CH4.
A long-term estimation of biogenic volatile organic compound (BVOC) emission in China from 2001–2016: the roles of land cover change and climate variability
Authors: Wang Hui , Wu Qizhong , Guenther Alex B. , Yang Xiaochun , Wang Lanning , Xiao Tang , Li Jie , Feng Jinming , Xu Qi , Cheng Huaqiong 
Published: March 2021

Abstract. Satellite observations reveal that China has been leading
the global greening trend in the past 2 decades. We assessed the impact of
land cover change as well as climate variability on total biogenic volatile organic compound (BVOC) emission in
China from 2001–2016. We found the greening trend in China is leading a
national-scale increase in BVOC emission. The BVOC emission level in 2016
could be 11.7 % higher than that in 2001 because of higher tree cover
fraction and vegetation biomass. On the regional scale, the BVOC
emission level from 2013–2016 could be 8.6 %–19.3 %
higher than that from 2001–2004 in hotspots including (1) northeastern
China, (2) Beijing and its surrounding areas, (3) the Qin Mountains, (4) Yunnan Province, (5) Guangxi–Guangdong provinces, and (6) Hainan island because
of the land cover change without considering the impact of climate
variability. The comparison among different scenarios showed that vegetation
changes resulting from land cover management are the main driver of BVOC
emission change in China. Climate variability contributed significantly to
interannual variations but not much to the changing trend during the study
period. In the standard scenario, which considers both land cover change and
climate variability, a statistically significant increasing trend can still be
found in regions including Beijing and its surroundings, Yunnan
Province, and Hainan island, and BVOC emission total amount in these regions
from 2013–2016 is 11.0 %–17.2 % higher that from 2001–2004. We
compared the long-term HCHO vertical columns (VC) from the satellite-based
Ozone Monitoring Instrument (OMI) with the estimation of isoprene emission
in summer. The results showed statistically significant positive correlation
coefficients over the regions with high vegetation cover fractions. In
addition, the isoprene emission and HCHO VC both showed statistically
significant increasing trends in the south of China where these two
variables have high positive correlation coefficients. This result may
support our estimation of the variability and trends of BVOC emission in
this region; however, the comparison still has large uncertainties since the
chemical and physical processes, including transportation, diffusion and
chemical reactions, were not considered. Our results suggest that the
continued increase in BVOC will enhance the importance of considering BVOC
when making policies for controlling ozone pollution in China along with
ongoing efforts to increase the forest cover fraction.
Two decades of distributed global radiation time series across a mountainous semiarid area (Sierra Nevada, Spain)
Authors: Aguilar Cristina , Pimentel Rafael , Polo María J. 
Published: March 2021

Abstract. The main drawback of the reconstruction of high-resolution
distributed global radiation (Rg) time series in mountainous semiarid
environments is the common lack of station-based solar radiation registers.
This work presents 19 years (2000–2018) of high-spatial-resolution (30 m) daily, monthly, and annual global radiation maps derived using the
GIS-based model proposed by Aguilar et al. (2010) in a mountainous area in
southern Europe: Sierra Nevada (SN) mountain range (Spain). The model was
driven by in situ daily global radiation measurements, from 16 weather
stations with historical records in the area; a 30 m digital elevation model;
and 240 cloud-free Landsat images. The applicability of the modeling scheme
was validated against daily global radiation records at the weather
stations. Mean RMSE values of 2.63 MJ m−2 d−1 and best
estimations on clear-sky days were obtained. Daily Rg at weather
stations revealed greater variations in the maximum values but no clear
trends with altitude in any of the statistics. However, at the monthly and
annual scales, there is an increase in the high extreme statistics with the
altitude of the weather station, especially above 1500 m a.s.l. Monthly
Rg maps showed significant spatial differences of up to 200 MJ m−2 per month that clearly followed the terrain configuration. July and
December were clearly the months with the highest and lowest values of
Rg received, and the highest scatter in the monthly Rg values was
found in the spring and fall months. The monthly Rg distribution was
highly variable along the study period (2000–2018). Such variability,
especially in the wet season (October–May), determined the interannual
differences of up to 800 MJ m−2 yr−1 in the incoming global
radiation in SN. The time series of the surface global radiation datasets
here provided can be used to analyze interannual and seasonal variation
characteristics of the global radiation received in SN with high spatial
detail (30 m). They can also be used as cross-validation reference data for
other global radiation distributed datasets generated in SN with different
spatiotemporal interpolation techniques. Daily, monthly, and annual
datasets in this study are available at https://doi.org/10.1594/PANGAEA.921012 (Aguilar et al., 2021).
Diets of the Barents Sea cod (Gadus morhua) from the 1930s to 2018
Authors: Townhill Bryony L. , Holt Rebecca E. , Bogstad Bjarte , Durant Joël M. , Pinnegar John K. , Dolgov Andrey V. , Yaragina Natalia A. , Johannesen Edda , Ottersen Geir 
Published: March 2021

Abstract. A new dataset on the diet of Atlantic cod in the Barents Sea from the 1930s
to the present day has been compiled to produce one of the largest fish
diet datasets available globally. Atlantic cod is one of the most
ecologically and commercially important fish species in the North Atlantic.
The stock in the Barents Sea is by far the largest, as a result of both
successful management and favourable environmental conditions since the
early 2000s. As a top predator, cod plays a key role in the Barents Sea
ecosystem. The species has a broad diet consisting mainly of crustaceans and
teleost fish, and both the amount and type of prey vary in space and time.
The data – from Russia, Norway and the United Kingdom – represent
quantitative stomach content records from more than 400 000 fish and
qualitative data from 2.5 million fish. Many of the data are from joint
collaborative surveys between Norway and Russia. The sampling was conducted
throughout each year, allowing for seasonal, annual and decadal comparisons
to be made. Visual analysis shows cod diets have changed considerably from
the start of the dataset in the 1930s to the present day. There was a large
proportion of herring in the diets in the 1930s, whereas in more recent
decades capelin, invertebrates and other fish dominate. There are also
significant interannual asynchronous fluctuations in prey, particularly
capelin and euphausiids. Combining these datasets can help us understand how
the environment and ecosystems are responding to climatic changes, and what
influences the diet and prey switching of cod. Trends in temperature and
variability indices can be tested against the occurrence of different prey
items, and the effects of fishing pressure on cod and prey stocks on diet
composition could be investigated. The dataset will also enable us to
improve parametrization of food web models and to forecast how Barents Sea
fisheries may respond in the future to management and to climate change.
The Russian data are available through joint projects with the Polar Branch of
the Russian Federal Research Institute of Fisheries and Oceanography (VNIRO). The UK and Norwegian data (Townhill et al., 2020) are being released
with this paper at https://doi.org/10.21335/NMDC-2139169383.
&lt;i&gt;Selenogonus narinoensis&lt;/i&gt; Stirton, 1947 (Tayassuidae, Cetartiodactyla, Mammalia): taxonomic status and paleobiogeographic implications
Authors: Gasparini Germán M. , Moreno-Mancilla Oscar F. , Cómbita José L. 
Published: March 2021

Abstract. The species Selenogonus narinoensis was described by Stirton (1947) based on a single specimen which comes from sediments cropping out in the Cocha Verde locality, Nariño Department (Colombia), tentatively referred to the late Pliocene–Pleistocene (MGN 931; IGM p002118, Museo Geológico Nacional, Servicio Geológico Colombiano, Bogotá). However, morphological studies and comparative morphometric observations of the specimen suggest that (1) no diagnostic character supports the validity of the species Selenogonus narinoensis (here considered species inquirenda); (2) a combination of features (e.g., the mandibular condyle located behind the posterior edge of the vertical mandibular ramus, the angular process which projects laterally outwards, a bunolophodont crown morphology, a mesodont crown height, and a simple crown morphology of the third lobe of m3) indicates it belongs to the genus Platygonus; (3) this specimen corresponds to one of the largest South American peccaries; (4) taking into account certain anatomical characters as well as its morphometric range, this specimen is assigned to Platygonus cf. marplatensis. Even though the stratigraphic provenance of the specimen is still doubtful, it can be proposed that (1) it could be one of the most ancient records of tayassuids in South America, as would be expected given its geographical position, and (2) considering the new taxonomic proposal, this specimen represents the first record of Platygonus cf. marplatensis in Colombia and represents one of the northernmost South American records of the genus. This new interpretation would be of great relevance in the Great American Biotic Interchange due to its strategic geographical proximity to the Isthmus of Panama.
The benefit of brightness temperature assimilation for the SMAP Level-4 surface and root-zone soil moisture analysis
Authors: Qiu Jianxiu , Dong Jianzhi , Crow Wade T. , Zhang Xiaohu , Reichle Rolf H. , De Lannoy Gabrielle J. M. 
Published: March 2021

Abstract. The Soil Moisture Active Passive (SMAP) Level-4 (L4) product provides global estimates of surface soil moisture (SSM) and root-zone soil moisture (RZSM) via the assimilation of SMAP brightness temperature (Tb) observations into the NASA Catchment Land Surface Model (CLSM). Here, using in situ measurements from 2474 sites in China, we evaluate the performance of soil moisture estimates from the L4 data assimilation (DA) system and from a baseline “open-loop” (OL) simulation of CLSM without Tb assimilation. Using random forest regression, the efficiency of the L4 DA system (i.e., the performance improvement in DA relative to OL) is attributed to eight control factors related to the CLSM as well as τ–ω radiative transfer model (RTM) components of the L4 system. Results show that the Spearman rank correlation (R) for L4 SSM with in situ measurements increases for 77 % of the in situ measurement locations (relative to that of OL), with an average R increase of approximately 14 % (ΔR=0.056). RZSM skill is improved for about 74 % of the in situ measurement locations, but the average R increase for RZSM is only 7 % (ΔR=0.034). Results further show that the SSM DA skill improvement is most strongly related to the difference between the
RTM-simulated Tb and the SMAP Tb observation, followed by the error in precipitation forcing data and estimated microwave soil roughness parameter h. For the RZSM DA skill improvement, these three dominant control factors remain the same, although the importance of soil roughness exceeds that of the Tb simulation error, as the soil roughness strongly affects the ingestion of DA increments and further propagation to the subsurface. For the skill of the L4 and OL estimates themselves, the top two control factors are the precipitation error and the SSM–RZSM coupling strength error, both of which are related to the CLSM component of the L4 system. Finally, we find that the L4 system can effectively filter out errors in precipitation. Therefore, future development of the L4 system should focus on improving the characterization of the SSM–RZSM coupling strength.
Improved NMR transfer of magnetization from protons to half-integer spin quadrupolar nuclei at moderate and high MAS frequencies
Authors: Gomez Jennifer S. , Rankin Andrew G. M. , Trebosc Julien , Pourpoint Frederique , Tsutsumi Yu , Nagashima Hiroki , Lafon Olivier , Amoureux Jean-Paul 
Published: March 2021

Abstract. Half-integer spin quadrupolar nuclei are the only magnetic isotopes for the majority of the chemical elements. Therefore, the transfer of polarization from protons to these isotopes under magic-angle spinning (MAS) can provide precious insights into the interatomic proximities in hydrogen-containing solids, including organic, hybrid, nanostructured and biological solids. Furthermore, this transfer has recently been combined with dynamic nuclear polarization (DNP) in order to enhance the NMR signal of half-integer quadrupolar isotope. Nevertheless, the cross-polarization transfer lacks of robustness in the case of quadrupolar nuclei and we have recently introduced as an alternative technique a through-space refocused insensitive nuclei enhancement by polarization transfer (D-RINEPT) scheme combining hetero-nuclear dipolar recoupling built from adiabatic pulses and continuous wave decoupling. This technique has been demonstrated at 9.4 T with moderate MAS frequencies, νR ≈ 10-15 kHz, in order to transfer the DNP-enhanced 1H polarization to quadrupolar nuclei. Nevertheless, polarization transfers from protons to quadrupolar nuclei are also required at higher MAS frequencies in order to improve the resolution of 1H spectra. We investigate how this transfer can be achieved at νR ≈ 20 and 60 kHz. We demonstrate that the D-RINEPT sequence using adiabatic pulses still produces efficient and robust transfer but requires large rf-fields, which may not be compatible with the specifications of commonly employed MAS NMR probes. As an alternative, we introduce robust and efficient variants of D-RINEPT and PRESTO (phase-shifted recoupling effects a smooth transfer of order) sequences using symmetry-based recoupling schemes built from single and composite π-pulses. Their performances are compared using the average Hamiltonians and experiments at B0 = 18.8 T on γ-alumina and isopropylamine templated microporous aluminophosphate AlPO4-14, featuring low and significant 1H-1H dipolar interactions, respectively. These experiments demonstrate that the 1H magnetization can be efficiently transferred to 27Al nuclei using D-RINEPT with SR412(270090180) recoupling, and PRESTO with R2227(1800) or R1672(270090180) schemes at νR = 20 or 62.5 kHz, respectively. The D-RINEPT and PRESTO recouplings complement each other since the latter is affected by dipolar truncation, whereas the former is not.
Entre uma consciência que recorta e um intelecto que totaliza
Authors: Teixeira Rafael Henrique 
Published: March 2021

O presente artigo apresenta uma reflexão comparativa entre as obras de Claude Lévi-Strauss e Henri Bergson. Tomo como ponto de partida os modos com os quais trabalham as noções de continuidade e descontinuidade, visando mostrar como essas noções se localizam no interior de uma problemática mais ampla, a qual julgo ser compartilhada por ambos: a questão da consciência e seu comércio com o real. Para tal, algo imprescindível é a operacionalidade que cada um confere ao elemento simbólico da experiência humana. É exatamente esse trato diferencial com o qual os signos são figurados em cada uma das obras, ora como impedimento, ora como condição de possibilidade de integração da experiência sensível, que nos permite vislumbrar os diferentes modos como esses autores prosseguem cada qual sua análise do comércio acima referido.
Efeitos da Ayahuasca em medidas psicométricas de pânico, ansiedade e desesperança
Authors: Dos Santos Rafael Guimarães 
Published: March 2021

A ayahuasca é utilizada como sacramento de religiões como o Santo Daime, a Barquinha, a União do Vegetal e as suas dissidências. Nesses contextos, é geralmente preparada utilizando talos de Banisteriopsis caapi e folhas de Psychotria viridis, sendo seus principais alcalóides as beta-carbolinas harmina, tetrahidroharmina (THH) e harmalina e a triptamina dimetiltriptamina (DMT) (Callaway, 2005; Callaway et al.,2005). Está bem estabelecido que sintomas relacionados à ansiedade, ao pânico e à depressão são atenuados de modo significativo por agonistas serotoninérgicos como inibidores da recaptação de serotonina e da MAO-A (Wikinski, 2004; Nash & Nutt, 2005; Starcevic, 2006). O fato de que os alcalóides presentes na ayahuasca inibem a recaptação de serotonina (THH) e a MAO-A (harmina, THH e harmalina) (McKenna, 2004) e exercem atividade agonista serotoninérgica direta (DMT) (Smith et al., 1998) sugere que a ayahuasca pode atenuar estados emocionais regulados pelo sistema serotoninérgico. Estudos anteriores sugerem que a ayahuasca exerce papel terapêutico em casos de depressão e ansiedade (Grob et al., 2004).
debate sobre o PCC
Authors: Manso Bruno Paes 
Published: March 2021

Em 24/01/2010, o Caderno Metrópole do jornal O Estado de São Paulo publicou parcialmente uma entrevista realizada pelo repórter – e doutorando em Ciência Política na USP – Bruno Paes Manso a quatro jovens pesquisadores sobre o Primeiro Comando da Capital. Embora esta entrevista fosse inicialmente destinada ao público leitor do jornal, o denso debate suscitado entre os pesquisadores teve como produto respostas com um forte teor teórico-metodológico, indissociável dos dados que cada um vem coletando. Por essa razão, propomos aos pesquisadores – que aceitaram prontamente – que a entrevista fosse publicada na íntegra nesta edição da r@u. Pretendemos, com isso, disponibilizar ao público acadêmico o debate em torno de um assunto tão presente na vida dos moradores de São Paulo: o Primeiro Comando da Capital.
Táticas táteis ou um certo tato tático:
Authors: Freire Bernardo Curvelano 
Published: March 2021

O presente trabalho tem como objetivo realizar uma descrição intensiva do filme Les Maîtres Fous de Jean Rouch, filmado em 1955, buscando explorar as táticas de filmagem e montagem com uma leitura lastrada por algumas dos horizontes do surrealismo enquanto projeto estético-político. Ao invés de discutir aspectos exógenos, contudo, o que viso é mostrar como o filme em questão se apresenta como um objeto experimental que apresenta um desafio, uma tentação, orientação própria de um projeto surrealista. Assim, espero apresentar alguns dos temas de Rouch segundo o conjunto de táticas indispensáveis para se considerar o filme como ação de etno-política pela qual a fórmula antropologia compartilhada se apresenta, em especial descrevendo a cadeia extensa entre os participantes cujo filme serve de nexo para a relação. Para tal discuto as noções de tátil e tático como elementos de tentação ao corpo e ao pensamento como preâmbulo de uma excursão decerto predatória no ambiente cinematográfico de Les Maîtres Fous, cuja descrição minuciosa da montagem permite compreender os tempos que constituem a forma de extensão e provocação do pensamento, orquestrados peloantropólogo e cineasta francês. Vale notar que o presente artigo tem como fundamentouma descrição por extenso, ela mesma problematização um tanto quanto surrealista, oque acarreta alguns riscos ao escritor e ao leitor.
Antropólogas gringas
Authors: Echazú Ana Gretel , Gutel Cécilia 
Published: March 2021

O presente trabalho tenta colocar em consideração, sob uma ótica reflexiva, as modificações na própria perspectiva de raça que duas jovens antropólogas (uma da Argentina, a outra da França) sofreram no decorrer das suas pesquisas no Brasil. Tais reflexões incluem uma análise do significado que o conceito de “raça” teve nos seus contextos antropológicos acadêmicos de origem, e o peso das noções corporais que apareceram nas interações nos seus próprios campos de pesquisa e nas universidades locais com as quais interagiram. Esse texto foi escrito à duas mãos, e com isso tenta resgatar a necessária polifonia da produção antropológica. Também coloca algumas divergências e conflitos no self representacional da antropologia, iluminando aspectos da sua diversidade focando especialmente a nacionalidade do antropólogo e a sua formação antropológica de origem.