Introduction: Toward More Inclusive and Comparative Perspectives in the Histories of Geographical Knowledge

Over the past three decades, feminist historiography of geography has begun to situate women's contribution to the production of geographical knowledge within the histories of geography, at times against the conviction of skeptical colleagues. In this Focus Section introduction, we renew Domosh's (1991a Domosh, M. 1991a. Beyond the frontiers of geographical knowledge. Transactions of the Institute of British Geographers 16 (4): 488–90.[Crossref], [Web of Science ®] , [Google Scholar], 1991b ———. 1991b. Toward a feminist historiography of geography. Transactions of the Institute of British Geographers 16 (1): 95–104.[Crossref], [Web of Science ®] , [Google Scholar]) call for creating more inclusive feminist histories of geography by situating the three focus section articles on the careers and contributions of women in twentieth-century geographical practice and knowledge production in the United Kingdom and the United States within wider debates about diverse, unfamiliar, and previously hidden aspects of geographical knowledge production. We argue that feminist historiography of geography and feminist historical geography could benefit from continuously diversifying inclusive and comparative research perspectives, and from unlocking diverse archives, to enhance understanding of why and how some male and some female gatekeepers have been more supportive of women than others.     

Feminizing the University: The Mobilities,Careers, and Contributions of Early Female Academics in the University of Cambridge, 1926–1955

This article examines the role of early female academics at the University of Cambridge in the production and dissemination of knowledge between 1926 and 1955. A statistical comparison of women's use of academic leave of absence with that of their male colleagues reveals that, across disciplines, women were less integrated into (inter)national knowledge networks and thus less visible in their epistemic communities than men because women focused their academic leaves more on research, rarely attended conferences, traveled overseas less often than men, and went more frequently to destinations within Europe than the United States as the new economic hegemon. Biographical case studies of these early female academics demonstrate the importance, variously, of their upper middle-class background, academic excellence, and familial and nonfamilial patronage in developing their careers, overcoming multiple hurdles, and producing intellectual contributions of equal quality to that of their male peers. Conceptually, this article calls for the inclusion of academic travelers from disciplines other than geography into feminist histories of geographical knowledge and argues that rather than stereotyping gender differences, greater comparative research on the experiences of female and male academics is needed to understand the mechanisms of gender inequality within the university.     

附有长度约束的模糊度解算方法比较

整周模糊度解算方法的合理选择是GNSS定向处理中的关键问题,针对此问题,该文对GNSS定向中的LAMBDA_C和CLAMBDA两种附有基线长约束的模糊度固定方法的性能进行了详细的对比分析。结果显示,相对于经典的基于Ratio检验的LAMBDA算法,LAMBDA_C和CLAMBDA均可提高模糊度固定率和正确率,尤其是在单频单系统下提高效果更为显著;CLAMBD的总体固定效果略优于LAMBDA_C,但后者的解算效率更高。     

Effects of Tidal Flooding on Juvenile Willows

Tidal wetlands are affected by sea level rise. In the tidal freshwater stretches of estuaries in the temperate zone, willows (Salix spp.) form tidal freshwater forests above the mean high water level. Willows tolerance to prolonged periodic flooding in riverine systems is well documented, whereas effects of tidal flooding on willows are largely unknown. Flooding stress may play a major role in regeneration failure of willows in tidal forest stands along estuarine shores, and juvenile willows might be specifically affected by partial or total submergence. To assess the tolerance of juvenile willows to tidal flooding, we conducted a mesocosm experiment with cuttings from Salix alba and Salix viminalis, which are both characteristic species for tidal freshwater forests in Europe. Cuttings originating from either fresh or brackish tidal forest stands were grown under four tidal treatments with up to a tidal flooding of 60 cm. A general tolerance to a tidal flooding of 60 cm was observed in chlorophyll fluorescence, growth rates, and biomass production in both willow species. Overall, S. alba showed higher leaf and shoot growth, whereas S. viminalis produced more biomass. S. alba with brackish origin performed worst with increasing tidal flooding, suggesting a possible pre-weakening due to stressful site conditions in tidal wetlands at the estuarine brackish stretch. This study demonstrates that juvenile willows of S. alba and S. viminalis tolerate tidal flooding of up to 60 cm. It is concluded that tidal inundation acts as a stress by causing submergence and soil anaerobiosis, but may also act as a subsidy by reestablishing aerobic conditions and thus maintaining willows performance. Therefore, we suggest investigations on Salix tidal flooding tolerance and possible effects of willows on tidal wetland accretion under estuarine field conditions.     

非完整约束的OD/SINS自适应组合导航方法

在地面车载组合导航GNSS/OD/SINS中,全球导航卫星系统（GNSS）信号容易受到环境的干扰甚至发生中断,将非完整性约束（NHC）应用于里程计（OD）/捷联惯性导航系统（SINS）组合,可以有效抑制GNSS信号中断期间组合导航系统的误差发散。通常NHC的噪声设定基于固定的经验值,然而在实际运动过程中,车辆运行轨迹复杂多变,其运动状态不能完全满足NHC前提假设,经验给定的噪声无法准确反映车辆实际运动情况。为此,本文分析了NHC噪声与车辆运动状态的关系,构建了一种基于车辆运动状态的NHC噪声自适应方法。通过所选场景的实测数据验证表明：采用噪声自适应的NHC/OD/SINS组合导航结果相比于固定噪声的NHC/OD/SINS组合,在GNSS信号中断110 s、车辆连续转弯的情况下,最大水平位置误差减小了68.4%;在GNSS信号中断74 s、车辆直线行驶的情况下,最大水平位置误差减小了87.3%;能较好地抑制GNSS中断期间组合导航系统的误差发散。     

Can Jupiters be found by monitoring Galactic bulge microlensing events from northern sites?

In 1998 the EXPORT team monitored microlensing event light curves using a charge-coupled device (CCD) camera on the IAC 0.8-m telescope on Tenerife to evaluate the prospect of using northern telescopes to find microlens anomalies that reveal planets orbiting the lens stars. The high airmass and more limited time available for observations of Galactic bulge sources make a northern site less favourable for microlensing planet searches. However, there are potentially a large number of northern 1-m class telescopes that could devote a few hours per night to monitor ongoing microlensing events. Our IAC observations indicate that accuracies sufficient to detect planets can be achieved despite the higher airmass.     

Mapping the narrative positions of new political groups under the UNFCCC

Since the mid-1990s, the aim of keeping climate change within 2?°C has become firmly entrenched in policy discourses. In the past few years, the likelihood of achieving it has been increasingly called into question. The debate around what to do with a target that seems less and less achievable is, however, only just beginning. As the UN commences a two-year review of the 2?°C target, this article moves beyond the somewhat binary debates about whether or not it should or will be met, in order to analyse more fully some of the alternative options that have been identified but not fully explored in the existing literature. For the first time, uncertainties, risks, and opportunities associated with four such options are identified and synthesized from the literature. The analysis finds that the significant risks and uncertainties associated with some options may encourage decision makers to recommit to the 2?°C target as the least unattractive course of action.     

Solid state CPMAS C and N NMR spectroscopy in organic geochemistry and how spin dynamics can either aggravate or improve spectra interpretation

Because the ongoing discussion about the reliability of solid state cross polarization magic angle spinning (CPMAS) nuclear magnetic resonance (NMR) spectroscopy still leaves uncertainty with respect to its usefulness in organic geochemistry, the present work provides a brief introduction into the basic principles of this technique and gives some explanation about the potential source of non-quantitative results. In addition, relaxation data are supplied which are necessary for the correct adjustment of NMR acquisition parameters. High contents of paramagnetics or moisture indeed affect the CP dynamics, complicating quantification of solid state NMR data obtained with a standard protocol. Whereas the latter can be avoided by carefully drying the sample, the first is often circumvented by demineralization with hydrofluoric acid (HF). Although this can yield considerable organic matter loss, the given examples demonstrate that differences in the intensity distribution of the spectra before and after HF treatment are most likely due to a selective alteration of the relaxation kinetics of protons closely interacting with paramagnetics. It is further shown that single pulse excitation does not necessarily provide quantitative data, since some geopolymers (e.g. cellulose) relax extremely slowly. At high magnetic fields and low spinning speeds, spinning side bands can overlap with relevant signals and obscure the intensity distribution. At spinning speeds >6 kHz, the range of the correct Hartmann-Hahn match is reduced, resulting in a preferential intensity loss of weakly coupling carbons which can be avoided by the application of special pulse sequences. In principal, the acquisition of quantitative CPMAS NMR data from geochemical samples is possible, although this often requires an in depth analysis of the relaxation parameters. Further, the latter also represents a powerful tool for the identification of geochemical compounds by providing additional information about their physical status and their spatial relationships to each other.     

GOCE: precise orbit determination for the entire mission

The Gravity field and steady-state Ocean Circulation Explorer (GOCE) was the first Earth explorer core mission of the European Space Agency. It was launched on March 17, 2009 into a Sun-synchronous dusk-dawn orbit and re-entered into the Earth’s atmosphere on November 11, 2013. The satellite altitude was between 255 and 225 km for the measurement phases. The European GOCE Gravity consortium is responsible for the Level 1b to Level 2 data processing in the frame of the GOCE High-level processing facility (HPF). The Precise Science Orbit (PSO) is one Level 2 product, which was produced under the responsibility of the Astronomical Institute of the University of Bern within the HPF. This PSO product has been continuously delivered during the entire mission. Regular checks guaranteed a high consistency and quality of the orbits. A correlation between solar activity, GPS data availability and quality of the orbits was found. The accuracy of the kinematic orbit primarily suffers from this. Improvements in modeling the range corrections at the retro-reflector array for the SLR measurements were made and implemented in the independent SLR validation for the GOCE PSO products. The satellite laser ranging (SLR) validation finally states an orbit accuracy of 2.42 cm for the kinematic and 1.84 cm for the reduced-dynamic orbits over the entire mission. The common-mode accelerations from the GOCE gradiometer were not used for the official PSO product, but in addition to the operational HPF work a study was performed to investigate to which extent common-mode accelerations improve the reduced-dynamic orbit determination results. The accelerometer data may be used to derive realistic constraints for the empirical accelerations estimated for the reduced-dynamic orbit determination, which already improves the orbit quality. On top of that the accelerometer data may further improve the orbit quality if realistic constraints and state-of-the-art background models such as gravity field and ocean tide models are used for the reduced-dynamic orbit determination.     

Chemical pathway analysis of the Martian atmosphere: CO2-formation pathways

The chemical composition of a planetary atmosphere plays an important role for atmospheric structure, stability, and evolution. Potentially complex interactions between chemical species do not often allow for an easy understanding of the underlying chemical mechanisms governing the atmospheric composition. In particular, trace species can affect the abundance of major species by acting in catalytic cycles. On Mars, such cycles even control the abundance of its main atmospheric constituent CO₂. The identification of catalytic cycles (or more generally chemical pathways) by hand is quite demanding. Hence, the application of computer algorithms is beneficial in order to analyze complex chemical reaction networks. Here, we have performed the first automated quantified chemical pathways analysis of the Martian atmosphere with respect to CO₂-production in a given reaction system. For this, we applied the Pathway Analysis Program (PAP) to output data from the Caltech/JPL photochemical Mars model. All dominant chemical pathways directly related to the global CO₂-production have been quantified as a function of height up to 86 km. We quantitatively show that CO₂-production is dominated by chemical pathways involving HO_x and O_x. In addition, we find that NO_x in combination with HO_x and O_x exhibits a non-negligible contribution to CO₂-production, especially in Mars’ lower atmosphere. This study reveals that only a small number of chemical pathways contribute significantly to the atmospheric abundance of CO₂ on Mars; their contributions to CO₂-production vary considerably with altitude. This analysis also endorses the importance of transport processes in governing CO₂-stability in the Martian atmosphere. Lastly, we identify a previously unknown chemical pathway involving HO_x, O_x, and HO₂-photodissociation, contributing 8% towards global CO₂-production by chemical pathways using recommended up-to-date values for reaction rate coefficients.