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The streamwise effective slope ( ES x ), which is the mean absolute streamwise gradient of the roughness, is considered to be a key parameter in predicting the drag penalty of rough-wall turbulent boundary-layers. However, many real-world rough surfaces are multi-scaled. For such surfaces, ES x can be unbounded and its value can be dominated by scales of the topography that are invisible to the flow. To illustrate this, a campaign of drag balance measurements was conducted with a set of machined surfaces. A baseline surface is prepared with fine machining parameters. By coarsening the machining precision, artefacts called 'scallops' are introduced which increases the 'measured' ES x without changing other geometrical statistics. The drag of the 'scalloped' surfaces is higher than the baseline surface, with the relative drag increase scaling with the viscous scaled scallop height, but only when their height exceeds 2 ∼ 3 times the viscous length scale. Further, the drag of one of the 'scalloped' cases, even when the scallop height is O (10) viscous units, is seen to be much lower ( ∼ 28 %) than a case with matched ES x , but where the ES x results from larger scale features. These findings confirm that for multi-scaled surfaces, ES x may be a misleading topographical metric for drag (or k s ) prediction and one must consider which scales contribute to the average slope of a surface. [ABSTRACT FROM AUTHOR]

In 1643, a manuscript was sent from Batavia to Amsterdam. It described in vivid detail a world virtually unknown to the West, that of South-Indian Hinduism, taken from the words of local Brahmins and drawn up by VOC minister Abraham Rogerius. It was not until 1651 that De Open-Deure tot het Verborgen Heydendom appeared from the presses of the Leiden printing house of François Hackius. By then, its author had died, and circumstances regarding the actual publication are shrouded in mystery. This is also true about the life of Abraham Rogerius and the identity of the Open-Deure's anonymous editor, A.W. JCtus. Traditionally associated with the Polish Socinian theologian Andreas Wissowatius, A.W's annotations added a wealth of scholarly detail to Rogerius plain narrative. In this paper, I greatly expand upon the existing biographies of Rogerius and draw lines between the various actors involved with the eventual publication of his writings. I provide a fresh insight into the editorial history and afterlife of the Open-Deure, showing that there are in fact two different editions that diverge at key points. Moreover, I demonstrate that the elusive A.W. JCtus is most certainly not Wissowatius, but instead the Leiden lawyer and politician Arnoldus Wittens. [ABSTRACT FROM AUTHOR]

First‐generation, low‐income (FGLI) students attend college at historically high rates in the United States. However, FGLI students continue to struggle in transitioning to college, particularly in elite universities. In this article, we engage with interview and supplemental survey data from 40 FGLI students at an elite university to demonstrate how self‐advocacy skills—conceptualized as a form of cultural capital—can support FGLI students' transition into college. We do this through the case of pre‐orientation programs, which are increasingly offered across universities, where half of the sample participated in pre‐orientation and half did not. We interviewed both subsets at the start of their first academic year, as well as during their COVID‐19‐induced departure from campus residences. In response, we argue that students who participated in pre‐orientation more often demonstrate self‐advocacy skills, both in‐person and online, especially in comparison with those who did not participate. We show that forming relationships with peers, as well as faculty and staff, during pre‐orientation is key to enacting self‐advocacy. Lastly, we also respond to previous studies that typically associate self‐advocacy skills with the cultural competencies of higher‐income and continuing‐generation students, while making clear how these skills can benefit FGLI students in transitioning into school. [ABSTRACT FROM AUTHOR]

Air pollution is still a major public health issue, which makes monitoring air quality a necessity. Mobile, low-cost air quality measurement devices can potentially deliver more coherent data for a region or municipality than stationary measurement stations are capable of due to their improved spatial coverage. In this study, air quality measurements obtained during field tests of our low-cost air quality sensor node (sensor-box) are presented and compared to measurements from the regional air quality monitoring network. The sensor-box can acquire geo-tagged measurements of several important pollutants, as well as other environmental quantities such as light and sound. The field test consists of sensor-boxes mounted on utility vehicles operated by municipalities located in Central Switzerland. Validation is performed against a measurement station that is part of the air quality monitoring network of Central Switzerland. Often not discussed in similar studies, this study tests and discusses several data filtering methods for the removal of outliers and unfeasible values prior to further analysis. The results show a coherent measurement pattern during the field tests and good agreement to the reference station during the side-by-side validation test. [ABSTRACT FROM AUTHOR]

At present, the distribution of plastic debris in the ocean water column remains largely unknown. Such information, however, is required to assess the exposure of marine organisms to plastic pollution as well as to calculate the ocean plastic mass balance. Here, we provide water column profiles (0–300 m water depth) of plastic (0.05–5 cm in size) concentration and key planktonic species from the eastern North Atlantic Ocean. The amount of plastic decreases rapidly in the upper few meters, from ~ 1 item/m3 (~ 1000 µg/m3) at the sea surface to values of ~ 0.001–0.01 items/m3 (~ 0.1–10 µg/m3) at 300 m depth. Ratios of plastic to plankton varied between ~ 10–5 and 1 plastic particles per individual with highest ratios typically found in the surface waters. We further observed that pelagic ratios were generally higher in the water column below the subtropical gyre compared to those in more coastal ecosystems. Lastly, we show plastic to (non-gelatinous) plankton ratios could be as high as ~ 102–107 plastic particles per individual when considering reported concentrations of small microplastics < 100 μm. Plastic pollution in our oceans may therefore soon exceed estimated safe concentrations for many pelagic species. [ABSTRACT FROM AUTHOR]

Illicit supply chains for products like counterfeit Personal Protective Equipment (PPE) are characterized by sparse data and great uncertainty about the operational and logistical structure, making criminal activities largely invisible to law enforcement and challenging to intervene in. Simulation is a way to get insight into the behavior of complex systems, using calibration to tune model parameters to match its real-world counterpart. Calibration methods for simulation models of illicit supply chains should work with sparse data, while also tuning the structure of the simulation model. Thus, this study addresses the question: "To what extent can various model calibration techniques reconstruct the underlying structure of an illicit supply chain when varying the degree of data sparseness?" We evaluate the quality-of-fit of a reference technique, Powell's Method, and three model calibration techniques that have shown promise for sparse data: Approximate Bayesian Computing, Bayesian Optimization, and Genetic Algorithms. For this, we use a simulation model of a stylized counterfeit PPE supply chain as ground truth. We extract data from this ground truth and systematically vary its sparseness. We parameterize structural uncertainty using System Entity Structure. The results demonstrate that Bayesian Optimization and Genetic Algorithms are suitable for reconstructing the underlying structure of an illicit supply chain for a varying degree of data sparseness. Both techniques identify a diverse set of optimal solutions that fit with the sparse data. For a comprehensive understanding of illicit supply chain structures, we propose to combine the results of the two techniques. Future research should focus on developing a combined algorithm and incorporating solution diversity. [ABSTRACT FROM AUTHOR]

Background: There is no consensus about the optimal treatment of anterior inferior ligament avulsion fractures of the ankle. The aim of this study is to provide insights regarding the incidence of anterior inferior ligament avulsion fractures, the association with fracture type, and correlation with treatment.Methods: This study is a retrospective analysis in a level-1 trauma center of adult patients with an ankle fracture operated between the dates 01-01-2009 and 01-09-2017 who had a pre- and postoperative CT-scan. Within the study population, the incidence of AITFL avulsion fracture was defined. Primary outcome was the type of avulsion fracture and related treatment. Secondary outcome was additional surgery in relation to the initial treatment.Results: In total, 65 of 252 (25.8%) patients were diagnosed with an anterior inferior ligament avulsion fracture. Zero patients had a Wagstaffe type 1 fracture, 28 (43.1%) had a type 2, 32 (49.2%) had a type 3, and 5 (7.7%) had a type 4. There was a correlation between Wagstaffe type 2 and Weber B fractures, p < 0.0001, and Wagstaffe type 3 avulsions were correlated with a Weber C fracture, p < 0.0001. Thirty-five of the avulsed fragments (53.8%) were smaller than 5 mm. In 13 (20%) of patients with anterior inferior ligament avulsion fracture, the avulsed fragments were directly fixated during initial surgery. Size and direct fixation of the fragment were significantly correlated (p < 0.0001). Within the anterior inferior ligament avulsion fracture group, only a total of four patients (6.2%) underwent a revision.Conclusion: In the current study, an incidence of 25.8% of anterior inferior ligament avulsion fracture in surgically treated ankle fractures is reported. A correlation between the type of Wagstaffe injury and Weber classification was showed. Most fragments smaller than 5 mm were not fixated; however, not all injuries needed syndesmotic screws due to syndesmotic instability.Level Of Evidence: Level IV. [ABSTRACT FROM AUTHOR]

Aims/Purpose: To assess the clinical outcomes subsequent to the implantation of a Baerveldt 350 drainage device, utilizing different restrictive methodologies to prevent sudden postoperative hypotony (HT) (IOP <6 mmHg), and their subsequent impact on the incidence of a Hypertensive phase (HP). Methods: A retrospective observational analysis of 71 consecutive eyes that had a Baerveldt 350 implanted. 50 eyes had 6 or 7/0 polyglactin tube ligation (ligature group = LG) and 21 eyes had a 3/0 polypropylene intraluminal tear cord 3/0 added to the ligation (ripcord‐ligature group = RLG), which was manually removed at the surgeon's discretion after spontaneous opening of the polyglactin. Intraocular pressure (IOP) and ocular hypotensive medication (OHM) lowering, failure rate, complete and partial success (CS and PS) and presence of HP were analysed. Results: The mean preoperative IOP was 26.14 (11.34) mmHg with 2.98 OHM for the LG and 28 (8.76) mmHg with 3.35 OHM for the RLG (p = 0.545 and p = 0.397). At the end of the follow‐up, the mean postoperative IOP was 13.35 (3.87) mmHg for the LG and 10.81(2.66) mmHg for the RLG (p = 0.01). The mean reduction of OHM was 2.25 (1.38) for the LG and 2.81 (1.6) for the RLG (p = 0.168). HP was noted in 26 patients (37.14%), 25 of them took place in the LG (50%); however, only 1 took place in the RLG (5%) (p = 0.00023). 35% of the patients who exhibited HP achieved CS, compared to 67.7% of the patients that did not show HP (p = 0.022). The survival analysis for a 12 months follow‐up period, showed that the estimate survival time for the LG was 10.97 (±0.521), and 11.64 (±0.342) for the RLG (p = 0.216). Two predictors were identified for risk of failure and CS: age of the patient before surgery (OR 0.157; 95% CI 0.029–0.865; p = 0.033) and the presence of HP (OR 3.90; 95% CI 1.189–12.794; p = 0.025). Lastly, HT was noted in 55 patients (80.9%), 45 of them took place in the LG (81.8%); however, only 10 took place in the RLG (18.2%) (Pearson Chi‐S p = 0.000225). Conclusions: Baerveldt 350 drainage device implantation has proven to be an effective procedure for glaucoma control. The use of the ripcord added to the absorbable ligature was associated with less risk of HP, and with better IOP results at the 12‐months follow‐up. Nevertheless, further research with larger population and larger follow‐up is needed to obtain robust results. [ABSTRACT FROM AUTHOR]

Aims/Purpose: To investigate prospectively macular microvascular changes in patients with glaucoma and identify common characteristics among the progressive eyes. Methods: A 12‐month prospective longitudinal study was performed with 124 open‐angle‐glaucoma‐eyes (GE). Glaucomatous progression was defined as a decrease of ≥5 μm in average or ≥7 μm in a sector of RNFL thickness. OMAG OCT microangiography (Angioplex, HD OCT, Cirrus 5000, Zeiss) was used to analyse the macular region. The statistical analysis was performed using the SPSS version 23.0 statistical package (SPSS Inc., IL). Results: Among the GE group, 22.36% of eyes showed progression, being the decrease of the Complete Region Macular Vessel Density (MVD) and Macular Capillary Perfusion Density (MPD) greater (−1.14 mm/mm2 and −3.18%) compared to non‐progressive eyes (−0.42 mm/mm2 and −1.02%) [p = 0.123 and 0.057], being the temporal and superior sectors for both MVD and MPD, the ones that showed greater differences (−1.44 mm/mm2, −1.11 mm/mm2, −3.6% and −2.95% respectively) [p > 0.05 for all]. Characteristics as elevated intraocular pressure (IOP) (17.29 vs 14.87 mmHg), thinner central corneal thickness (CCT) (521.53 vs 538.65 μm) and lower ocular perfusion pressure (OPP) (45.88 vs 49.21 mmHg) were significantly different in those progressive GE [p < 0′05 for all]. Nevertheless, increased vertical cup to disc ratio (CDV) (0.64 vs 0.63) and minimum ganglion cell layer thickness (GCLM) (58,82 vs 56.51 μm) were not significantly different in progressive GE [p = 0.768 and 0.249]. Conclusions: Data showed that when glaucomatous progression took place, stronger vascular changes occurred in the macular area, as greater decrease of MVD and MPD specially in the temporal and superior sectors. In addition, common characteristics as elevated intraocular pressure, thinner central corneal thickness and lower ocular perfusion pressure were identified in progressive GE. Nevertheless, further research with larger population and larger follow‐up is needed to obtain stronger results. [ABSTRACT FROM AUTHOR]

This paper describes the lithic aggregates from Sitwe 23 (SW23), a Stone Age locality in a previously unstudied region of the northern Luangwa Valley, Zambia. This area yielded two surface lithic scatters containing abundant artifacts derived from Pleistocene sediments on uplifted terrain and exposed by recent erosion on two adjacent terraces. The scatters are time-averaged palimpsests formed by deflation, but most of the lithics lack evidence of significant fluvial transport or post-depositional damage, indicating minimal horizontal displacement. Typological and attribute analyses of samples from both spurs reveal predominantly simple and expedient core and flake technologies, as well as sophisticated biface manufacture and Levallois technique producing flakes and points that are differentially distributed between the terraces. The artifacts identified in this analysis include types conventionally considered diagnostic of the Acheulean, Sangoan, and Middle Stone Age, suggesting that the collections may document one or more temporal windows during the Chibanian age (770–126 ka). Whether artifacts in these samples were originally deposited sequentially or concurrently is not yet known and alternative hypotheses are presented and discussed. The collections are compared to sites in Zambia and the northern Lake Malawi basin and found to be similar technologically but typologically different. Given the paucity of previously known Ston Age archaeological sites in the region, our work now demonstrates that northern Luangwa has significant archaeological potential and deserves further study. [ABSTRACT FROM AUTHOR]

Drawing on 48 interviews with science, technology, engineering and mathematics (STEM) doctoral students at a private research university in the United States (US), we examine how students make sense of the preponderance of men at the faculty level despite increasing gender parity among students. Students' primary explanatory frame, historical bias, suggests that the gender gap will disappear when enough women attain their doctorates (PhDs). Competing frames include innate and constructed gender difference and the perceived incompatibility between a woman's body clock and an academic tenure clock. We argue that the frames that students use to explain the gender gap shed light on the cultural context of STEM, which is characterized by a tension between the belief in a meritocratic system and the acknowledgement of structural inequality. We suggest that men and women's preference for explanations that preclude bias, in light of women students' own experiences with sexism in graduate school, contributes to the reproduction of inequality by rendering invisible structural barriers to gender equality. [ABSTRACT FROM AUTHOR]

The field of transgender studies has grown exponentially in sociology over the last decade. In this review, we track the development of this field through a critical overview of the sociological scholarship from the last 50 years. We identify two major paradigms that have characterized this research: a focus on gender deviance (1960s-1990s) and a focus on gender difference (1990s-present). We then examine three major areas of study that represent the current state of the field: research that explores the diversity of transgender people's identities and social locations, research that examines transgender people's experiences within institutional and organizational contexts, and research that presents quantitative approaches to transgender people's identities and experiences. We conclude with an agenda for future areas of inquiry. [ABSTRACT FROM AUTHOR]

This study deals with the thermodynamic modeling of biomass Gasifier–SOFC (Solid Oxide Fuel Cell)–GT (Gas Turbine) systems on a small scale (100 kW e ). Evaluation of an existing biomass Gasifier–SOFC–GT system shows highest exergy losses in the gasifier, gas turbine and as waste heat. In order to reduce the exergy losses and increase the system's efficiency, improvements are suggested and the effects are analyzed. Changing the gasifying agent for air to anode gas gave the largest increase in the electrical efficiency. However, heat is required for an allothermal gasification to take place. A new and simple strategy for heat pipe integration is proposed, with heat pipes placed in between stacks in series, rather than the widely considered approach of integrating the heat pipes within the SOFC stacks. The developed system based on a Gasifier–SOFC–GT combination improved with heat pipes and anode gas recirculation, increases the electrical efficiency from approximately 55%–72%, mainly due to reduced exergy losses in the gasifier. Analysis of the improved system shows that operating the system at possibly higher operating pressures, yield higher efficiencies within the range of the operating pressures studied. Further the system was scaled up with an additional bottoming cycle achieved electrical efficiency of 73.61%. [ABSTRACT FROM AUTHOR]

Harold Garfinkel's 1950s case study of 'Agnes' is broadly understood as the locus classicus of sociological research about transgender people. Drawing on an analysis of unpublished archival materials from Garfinkel and Robert J. Stoller, the lead psychiatrist on Agnes's case, I locate Agnes' experiences at UCLA within a larger history of theorizing about gender and sexuality within the social sciences, and within the emerging field of transgender studies. [ABSTRACT FROM AUTHOR]

Purpose: To investigate prospectively macular and peripapillary microvascular changes in patients with glaucoma and ocular hypertension. Methods: A 12‐month prospective longitudinal study was performed with 124 open‐angle‐glaucoma‐eyes (GE), 111 ocular‐hypertension‐eyes (OHE) and 98 gender and age matched control‐eyes (CE). Glaucomatous progression was defined as a decrease of ≥5 μm in average or ≥7 μm in a sector of RNFL thickness. OMAG OCT microangiography (Angioplex, HD OCT, Cirrus 5000, Zeiss) was used to analyse optic disc and macular regions. The statistical analysis was performed using Mann–Whitney‐Test with the SPSS version 23.0 statistical package (SPSS Inc., IL). Results: Among OHE and GE groups, 21.7% of eyes showed progression, being the decrease of Peripapillary Flux Index (PFI), Macular Vessel Density (MVD) and Macular Capillary Perfusion Density (MPD) greater (−0.0067; −0.696 mm/mm2 and −1.56%) compared to non‐progressive eyes (+0.0038; 0.527 mm/mm2 and 1.55%) being the nasal and inferior sectors for PFI, and the superior and temporal sectors for both MVD and MPD, the ones that showed greater differences [p = 0.015 and p < 0.001 for the last two]. Furthermore, Peripapillary Perfusion Density (PPD) showed non‐significant greater decrease (−0.347) compared to non‐progressive eyes (−0.324) [p = 0.775]. Characteristics as increased vertical cup to disc ratio (CDV) (0.64 vs. 0.57), elevated intraocular pressure (IOP) (18.25 vs. 15.40 mmHg), thinner central corneal thickness (CCT) (520.18 vs. 541.67 μm) and lower ocular perfusion pressure (OPP) (47.81 vs. 48.95 mmHg) were significantly different in those progressive OHE and GE [p < 0.05 for all]. Nevertheless, minimum ganglion cell layer thickness (GCLM) was only significantly lower in progressive GE (58.51 vs. 73.98 μm) [p = 0.036]. Conclusions: Data showed that when glaucomatous progression took place, stronger microvascular changes occurred in the macular and peripapillary areas, as greater decrease of MVD, MPD and PFI, especially in superior and temporal sectors for the macular area, and in nasal and inferior sectors for the peripapillary area. Nevertheless, further research with larger population and larger follow‐up is needed to obtain stronger results. [ABSTRACT FROM AUTHOR]

Background Among nanodrugs, PEGylated nanoliposomes loaded with an active agent are of major importance. In this paper we studied the structures and morphology of PEGylated nanoliposomes before and after remote loading with doxorubicin. Methods High-resolution structures were obtained by solution X-ray scattering combined with our advanced analysis tools. We studied the PEGylated liposomal doxorubicin (PLD) product Doxil ® , and its generics, where remote doxorubicin loading is performed by a gradient of ammonium sulfate, and LC100, a novel PLD under development, where remote loading was done by a gradient of ammonium methanesulfonate. The PLD structures were compared with drug-free nanoliposomes having identical composition. Results We determined the membrane electron density profiles of the empty and loaded PLDs, the thickness and density of the PEG layers, and the structure of the drug inside the liposomes. Conclusions The liposomal membranes had the same structure for both ammonium salts. We found that the drug formed crystals inside PLDs loaded by ammonium sulfate, whereas it had an amorphous morphology in the PLD loaded by ammonium methanesulfonate. The variations of the drug's structural parameters between the generics of Doxil ® are similar to the variations between batches of the same product, suggesting that all these products were structurally similar. General significance This paper demonstrates that solution X-ray scattering, when combined with our powerful analysis tools, can determine the high-resolution structure of complex non-crystallized nanoparticle dispersions used in nanomedicine, thereby providing useful physical insights into their functions. [ABSTRACT FROM AUTHOR]

We present an experimental study of noise in mid-infrared quantum cascade lasers (QCLs) of different designs. By quantifying the high degree of correlation occurring between fluctuations of the optical frequency and voltage between the QCL terminals, we show that electrical noise is a powerful and simple mean to study noise in QCLs. Based on this outcome, we investigated the electrical noise in a large set of 22 QCLs emitting in the range of 7.6-8 μm and consisting of both ridge-waveguide and buried-heterostructure (BH) lasers with different geometrical designs and operation parameters. From a statistical data processing based on an analysis of variance, we assessed that ridge-waveguide lasers have a lower noise than BH lasers. Our physical interpretation is that additional current leakages or spare injection channels occur at the interface between the active region and the lateral insulator in the BH geometry, which induces some extra noise. In addition, Schottky-type contacts occurring at the interface between the n-doped regions and the lateral insulator, i.e., iron-doped InP, are also believed to be a potential source of additional noise in some BH lasers, as observed from the slight reduction in the integrated voltage noise observed at the laser threshold in several BH-QCLs. [ABSTRACT FROM AUTHOR]

Mwanganda's Village (MGD) and Bruce (BRU) are two open-air site complexes in northern Malawi with deposits dating to between 15 and 58 thousand years ago (ka) and containing Middle Stone Age (MSA) lithic assemblages. The sites have been known since 1966 and 1965, respectively, but lacked chronometric and site formation data necessary for their interpretation. The area hosts a rich stone artifact record, eroding from and found within alluvial fan deposits exhibiting poor preservation of organic materials. Although this generally limits opportunities for site-based environmental reconstructions, MGD and BRU are located at the distal margins of the alluvial fan, where lacustrine lagoonal deposits were overprinted by a calcrete paleosol. This has created locally improved organic preservation and allowed us to obtain ecological data from pollen, phytoliths, and pedogenic carbonates, producing a regional- to site-scale environmental context for periods of site use and abandonment. Here, we integrate the ecological data into a detailed site formation history, based on field observations and micromorphology, supplemented by cathodoluminescence microscopy and μ-XRF. By comparing local, on-site environmental proxies with more regional indicators, we can better evaluate how MSA hunter-gatherers made decisions about the use of resources across the landscape. Our data indicate that while tree cover similar to modern miombo woodland and evergreen gallery forest prevailed at most times, MSA hunter-gatherers chose more locally open environments for activities that resulted in a lithic artifact record at multiple locations between 51 and 15 ka. • MSA foragers in a forested landscape in Malawi chose locally more open environments. • Micromorphology tackles complex formation histories at open-air sites. • Calcrete paleosols at the margins of Lake Malawi preserve environmental proxies. • Combining multi-scale proxies increases understanding of human activity in the landscape. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N2O) is an important greenhouse gas and ozone-depleting substance that has anthropogenic as well as natural marine and terrestrial sources. The tropospheric N2O concentrations have varied substantially in the past in concert with changing climate on glacial-interglacial and millennial timescales. It is not well understood, however, how N2O emissions from marine and terrestrial sources change in response to varying environmental conditions. The distinct isotopic compositions of marine and terrestrial N2O sources can help disentangle the relative changes in marine and terrestrial N2O emissions during past climate variations. Here we present N2O concentration and isotopic data for the last deglaciation, from 16,000 to 10,000 years before present, retrieved from air bubbles trapped in polar ice at Taylor Glacier, Antarctica. With the help of our data and a box model of the N2O cycle, we find a 30 per cent increase in total N2O emissions from the late glacial to the interglacial, with terrestrial and marine emissions contributing equally to the overall increase and generally evolving in parallel over the last deglaciation, even though there is no a priori connection between the drivers of the two sources. However, we find that terrestrial emissions dominated on centennial timescales, consistent with a state-of-the-art dynamic global vegetation and land surface process model that suggests that during the last deglaciation emission changes were strongly influenced by temperature and precipitation patterns over land surfaces. The results improve our understanding of the drivers of natural N2O emissions and are consistent with the idea that natural N2O emissions will probably increase in response to anthropogenic warming. [ABSTRACT FROM AUTHOR]

We demonstrate the first ultra-stable microwave generation based on a 1.5-μm diode-pumped solid-state laser (DPSSL) frequency comb. Our system relies on optical-to-microwave frequency division from a planar-waveguide external cavity laser referenced to an ultra-stable Fabry-Perot cavity. The evaluation of the microwave signal at ~10 GHz uses the transportable ultra-low-instability signal source ULISS, which employs a cryo-cooled sapphire oscillator. With the DPSSL comb, we measured −125 dBc/Hz phase noise at 1 kHz offset frequency, likely limited by the photo-detection shot-noise or by the noise floor of the reference cryo-cooled sapphire oscillator. For comparison, we also generated low-noise microwave using a commercial Er:fiber comb stabilized in similar conditions and observed >20 dB lower phase noise in the microwave generated from the DPSSL comb. Our results confirm the high potential of the DPSSL technology for low-noise comb applications. [ABSTRACT FROM AUTHOR]

Background: Radiosurgical treatment of brain lesions near motor or language eloquent areas requires careful planning to achieve the optimal balance between effective dose prescription and preservation of function. Navigated brain stimulation (NBS) is the only non-invasive modality that allows the identification of functionally essential areas by electrical stimulation or inhibition of cortical neurons analogous to the gold-standard of intraoperative electrical mapping. Objective: To evaluate the feasibility of NBS data integration into the radiosurgical environment, and to analyze the influence of NBS data on the radiosurgical treatment planning for lesions near or within motor or language eloquent areas of the brain. Methods: Eleven consecutive patients with brain lesions in presumed motor or language eloquent locations eligible for radiosurgical treatment were mapped with NBS. The radiosurgical team prospectively analyzed the data transfer and classified the influence of the functional NBS information on the radiosurgical treatment planning using a standardized questionnaire. Results: The semi-automatized data transfer to the radiosurgical planning workstation was flawless in all cases. The NBS data influenced the radiosurgical treatment planning procedure as follows: improved risk-benefit balancing in all cases, target contouring in 0 %, dose plan modification in 81.9 %, reduction of radiation dosage in 72.7 % and treatment indication in 63.7 % of the cases. Conclusions: NBS data integration into radiosurgical treatment planning is feasible. By mapping the spatial relationship between the lesion and functionally essential areas, NBS has the potential to improve radiosurgical planning safety for eloquently located lesions. [ABSTRACT FROM AUTHOR]

Background: Intracranial arteriovenous malformations (AVM) are known to be potent inductors of functional plasticity, and their vasculature makes standard functional imaging difficult. Here we conducted functional mapping of both primary motor cortex and speech related areas in patients with AVM using navigated transcranial magnetic stimulation (nTMS), which has been recently proven as a reliable noninvasive modality of preoperative functional brain mapping. Method: nTMS mapping was performed in ten patients with unruptured intracranial AVMs located in or near eloquent areas. Motor mapping was conducted for six patients with AVMs near the rolandic region, and speech mapping was performed for four patients with left perisylvian AVMs. After the examination, all patients were treated with surgery, radiosurgery or observed with best medical treatment on case-by-case basis. Results: Motor mapping allowed for delineation of the primary motor cortex, even if the anatomy was severely obscured by the AVM in all cases with rolandic AVMs. No plastic relocation of the primary motor cortex was observed. Repetitive stimulation of the left ventral precentral gyrus led to speech impairments in all four cases that underwent speech mapping. Right hemispheric involvement was observed in one out of four cases and potentially indicated plastic changes. No side effects were observed. Conclusion: nTMS allowed for detailed delineation of eloquent areas even within hypervascularized cortical areas. Our observations indicate that nTMS functional mapping is feasible not only in tumorous brain lesions, but also in AVMs. [ABSTRACT FROM AUTHOR]

An interview with Aline Kominsky-Crumb is presented. Topics covered include how her artistic self started to emerge at the age of 8 and how her secret artistic life sustained her, her notebooks where she drew humorous pictures of people that she knew and about her life and how she was called a camp follower because of her involvement with Robert Crumb.

We report on the measurement of the frequency noise properties of a 4.6-μm distributed-feedback quantum-cascade laser (QCL) operating in continuous wave near room temperature using a spectroscopic set-up. The flank of the R(14) ro-vibrational absorption line of carbon monoxide at 2196.6 cm is used to convert the frequency fluctuations of the laser into intensity fluctuations that are spectrally analyzed. We evaluate the influence of the laser driver on the observed QCL frequency noise and show how only a low-noise driver with a current noise density below ${\approx} 1~\mbox{nA/}\sqrt{}\mbox{Hz}$ allows observing the frequency noise of the laser itself, without any degradation induced by the current source. We also show how the laser FWHM linewidth, extracted from the frequency noise spectrum using a simple formula, can be drastically broadened at a rate of ${\approx} 1.6~\mbox{MHz/}(\mbox{nA/}\sqrt{}\mbox{Hz})$ for higher current noise densities of the driver. The current noise of commercial QCL drivers can reach several $\mbox{nA/}\sqrt{}\mbox{Hz}$, leading to a broadening of the linewidth of our QCL of up to several megahertz. To remedy this limitation, we present a low-noise QCL driver with only $350~\mbox{pA/}\sqrt{}\mbox{Hz}$ current noise, which is suitable to observe the ≈550 kHz linewidth of our QCL. [ABSTRACT FROM AUTHOR]

We present a detailed investigation of the noise properties of an optical frequency comb generated from a femtosecond diode-pumped solid-state laser operating in the 1.5-μm spectral region. The stabilization of the passively mode-locked Er:Yb:glass laser oscillator, referred to as ERGO, is achieved using pump power modulation for the control of the carrier envelope offset (CEO) frequency and by adjusting the laser cavity length for the control of the repetition rate. The stability and the noise of the ERGO comb are characterized in free-running and in phase-locked operation by measuring the noise properties of the CEO, of the repetition rate, and of a comb line at 1558 nm. The comb line is analyzed from the heterodyne beat signal with a cavity-stabilized ultra-narrow-linewidth laser using a frequency discriminator. Two different schemes to stabilize the comb to a radio-frequency (RF) reference are compared. The comb properties (phase noise, frequency stability) are limited in both cases by the RF oscillator used to stabilize the repetition rate, while the contribution of the CEO is negligible at all Fourier frequencies, as a consequence of the low-noise characteristics of the CEO-beat. A linewidth of ≈150 kHz and a fractional frequency instability of 4.2×10 at 1 s are obtained for an optical comb line at 1558 nm. Improved performance is obtained by stabilizing the comb to an optical reference, which is a cavity-stabilized ultra-narrow linewidth laser at 1558 nm. The fractional frequency stability of 8×10 at 1 s, measured in preliminary experiments, is limited by the reference oscillator used in the frequency comparison. [ABSTRACT FROM AUTHOR]

We apply a means to probe, stabilize, and control the size of lipid raft-like domains in vitro. In biomembranes the size of lipid rafts is ca. 10–30 nm.In vitro, mixing saturated and unsaturated lipids results in microdomains, which are unstable and coalesce. This inconsistency is puzzling. It has been hypothesized that biological line-active surfactants reduce the line tension between saturated and unsaturated lipids and stabilize small domains in vivo. Using solution X-ray scattering, we studied the structure of binary and ternary lipid mixtures in the presence of calcium ions. Three lipids were used: saturated, unsaturated, and a hybrid (1-saturated–2-unsaturated) lipid that is predominant in the phospholipids of cellular membranes. Only membranes composed of the saturated lipid can adsorb calcium ions, become charged, and therefore considerably swell. The selective calcium affinity was used to show that binary mixtures, containing the saturated lipid, phase separated into large-scale domains. Our data suggests that by introducing the hybrid lipid to a mixture of the saturated and unsaturated lipids, the size of the domains decreased with the concentration of the hybrid lipid, until the three lipids could completely mix. We attribute this behavior to the tendency of the hybrid lipid to act as a line-active cosurfactant that can easily reside at the interface between the saturated and the unsaturated lipids and reduce the line tension between them. These findings are consistent with a recent theory and provide insight into the self-organization of lipid rafts, their stabilization, and size regulation in biomembranes. [ABSTRACT FROM AUTHOR]

We describe a radio-frequency (RF) discriminator, or frequency-to-voltage converter, based on a voltage-controlled oscillator phase-locked to the signal under test, which has been developed to analyze the frequency noise properties of an RF signal, e.g., a heterodyne optical beat signal between two lasers or between a laser and an optical frequency comb. We present a detailed characterization of the properties of this discriminator and we compare it to three other commercially available discriminators. Owing to its large linear frequency range of 7 MHz, its bandwidth of 200 kHz and its noise floor below 0.01 Hz2/Hz in a significant part of the spectrum, our frequency discriminator is able to fully characterize the frequency noise of a beat signal with a linewidth ranging from a couple of megahertz down to a few hertz. As an example of application, we present measurements of the frequency noise of the carrier envelope offset beat in a low-noise optical frequency comb. [ABSTRACT FROM AUTHOR]

Abstract: Reconstructions of past atmospheric concentrations of greenhouse gases provide unique insight into the biogeochemical cycles and the past radiative forcing in the Earth''s climate system. We present new measurements of atmospheric nitrous oxide along the ice cores of the North Greenland Ice Core Project and Talos Dome sites. Using records of several other ice cores, we are now able to establish the first complete composite nitrous oxide record reaching back to the beginning of the previous interglacial about 140,000yr ago. On the basis of such composite ice core records, we further calculate the radiative forcing of the three most important greenhouse gases carbon dioxide, methane and nitrous oxide during more than a full glacial–interglacial cycle. Nitrous oxide varies in line with climate, reaching very low concentrations of about 200 parts per billion by volume during Marine Isotope Stages 4 and 2, and showing substantial responses to millennial time scale climate variations during the last glacial. A large part of these millennial time scale variations can be explained by parallel changes in the sources of methane and nitrous oxide. However, as revealed by high-resolution measurements covering the Dansgaard/Oeschger events 17 to 15, the evolution of these two greenhouse gases may be decoupled on the centennial time scale. Carbon dioxide and methane concentrations do not reach interglacial levels in the course of millennial time scale climate variations during the last glacial. In contrast, nitrous oxide often reaches interglacial concentrations in response to both, glacial terminations and Dansgaard/Oeschger events. This indicates, from a biogeochemical point of view, similar drivers in both temporal cases. While carbon dioxide and methane concentrations are more strongly controlled by climate changes in high latitudes, nitrous oxide emissions changes may mainly stem from the ocean and/or from soils located at low latitudes. Accordingly, we speculate that high latitudes could play the leading role to trigger glacial terminations. [Copyright &y& Elsevier]

Water-vapor-induced pressure broadening is reported for two NH3 absorption features at 6612.7 and 6596.4 cm−1 that are exploitable for gas sensing applications at atmospheric pressure. Absorption spectra of different NH3–H2O–N2 mixtures were measured at an elevated temperature of 70°C to enable high H2O concentrations to be reached. Line parameters were determined from a fitting procedure. The significantly greater values obtained for the H2O-broadening coefficients of the two lines compared to N2-broadening leads to cross-sensitivity effects in NH3 trace gas sensors based on spectroscopic techniques that are sensitive to the width of the analyzed absorption line, as is the case in a simple implementation of wavelength modulation spectroscopy or in photoacoustic spectroscopy. In such a case, cross-sensitivity results in inaccurate gas concentration retrieval when the composition of the diluting gas changes. H2O represents a potentially significant cross-sensitivity source as its concentration may be subject to large variations, especially in high-temperature applications where concentrations up to a couple of tens of percent may be encountered. In contrast to interference which can be minimized by an appropriate choice of the analyzed transitions, cross-sensitivity affects the entire spectrum of the analyte and is thus unavoidable in the mentioned type of gas sensors. [ABSTRACT FROM AUTHOR]

An extensive characterization of the spectral properties of a largely tunable laser in the 1.56-μm spectral range is reported. This device combines a vertical-cavity surface-emitting laser (VCSEL) with a micro-machined (MEMS) Bragg mirror in a very compact arrangement. The large tunability obtained by an electro-thermal actuation of the MEMS mirror makes this device very attractive for high-resolution spectroscopy. Relevant laser parameters for the implementation of wavelength modulation spectroscopy techniques in gas sensing, such as tuning and modulation properties, are presented. A preliminary gas spectroscopy experiment performed with this laser is also shown. [ABSTRACT FROM AUTHOR]

Rationale Studies reporting ecstasy-induced serotonintoxicity and (neuro)psychological dysfunctions have been conducted in young adults. Little is known about ecstasy effects later in life, when serotonin levels and cognition decrease as a consequence of normal ageing. Objective This study aimed to assess whether harmful effects of ecstasy only add to or also interact with agerelated neuropsychological decline. Methods Attention, verbal and visual memory, visuospatial ability, self-reported depression, sensation-seeking and impulsivity were assessed in middle-aged moderate to heavy ecstasy/polydrug users (n=17) and compared with none or very mild ecstasy using polydrug users (matched for age, gender, intelligence and other drugs; n=16) and a group of drug-naive controls (n=20). Results Moderate to heavy ecstasy/polydrug users performed significantly worse on a verbal memory task than none or very mild ecstasy using polydrug users and drug naives. Moderate and heavy ecstasy/polydrug users also differed significantly from drug-naives on measures of depression, sensation-seeking and impulsivity but not from none or very mild ecstasy-using polydrug users. Conclusion This study in middle-aged ecstasy/polydrug users replicated findings of studies in younger ecstasy users, showing a harmful effect of ecstasy on verbal memory. There was no clear support for an interaction between harmful effects of ecstasy use and age-related memory decline or mid-life depression. [ABSTRACT FROM AUTHOR]

Abstract: We present records of atmospheric nitrous oxide obtained from the ice cores of the European Project for Ice Coring in Antarctica (EPICA) Dome C and Dronning Maud Land sites shedding light on the concentration of this greenhouse gas on glacial–interglacial and millennial time scales. The extended EPICA Dome C record covers now all interglacials of the last 800,000 years and reveals nitrous oxide variations in concert with climate. Highest mean interglacial nitrous oxide concentrations of 280 parts per billion by volume are observed during the interglacial corresponding to Marine Isotope Stage 11 around 400,000 years before present, at the same time when carbon dioxide and methane reach maximum mean interglacial concentrations. The temperature reconstruction at Dome C indicates colder interglacials between 800,000 and 440,000 years before present compared to the interglacials of the last 440,000 years. In contrast to carbon dioxide and methane, which both respond with lower concentrations at lower temperatures, nitrous oxide shows mean interglacial concentrations of 4–19 parts per billion by volume higher than the preindustrial Holocene value during the interglacials corresponding to Marine Isotope Stage 9–19. At the end of most interglacials, nitrous oxide remains substantially longer on interglacial levels than methane. Nevertheless, nitrous oxide shows millennial-scale variations at the same time as methane throughout the last 800,000 years. We suggest that these millennial-scale variations have been driven by a similar mechanism as the Dansgaard/Oeschger events known from the last glacial. Our data lead to the hypothesis that emissions from the low latitudes drive past variations of the atmospheric nitrous oxide concentration. [Copyright &y& Elsevier]

A sensor based on quartz-enhanced photoacoustic spectroscopy (QEPAS) was evaluated for the detection of trace levels of ethylene at atmospheric pressure using a fiber coupled DFB diode laser emitting in the 1.62 µm spectral range. A noise-equivalent QEPAS signal of ∼4 ppm C2H4 was achieved for a 0.7 s data acquisition time using wavelength-modulation with a second-harmonic detection scheme on the strongest C2H4 absorption peak at 6177.14 cm−1 with an average optical power of ∼15 mW. Improved detection sensitivity of 0.5 and 0.3 ppm C2H4 (1 σ) was demonstrated using longer averaging time of 70 and 700 s, respectively. Important characteristics for the QEPAS based sensor operation in real-world conditions are presented, particularly the influence of external temperature variations. Furthermore, the response time of the ethylene sensor was measured in different configurations and it is shown that the QEPAS technique can provide a response time in a few seconds range even without active gas flow. [ABSTRACT FROM AUTHOR]

Ecstasy (±3,4-methylenedioxymethamphetamine) is a widely used recreational drug that may damage the serotonin system and may entail neuropsychological dysfunctions. Few studies investigated predictors for ecstasy use. Self-reported impulsivity does not predict the initiation of ecstasy use; the question is if neuropsychological indicators of impulsivity can predict first ecstasy use. This study tested the hypothesis that a neuropsychological indicator of impulsivity predicts initiation of ecstasy use. Decision-making strategy and decision-making reaction times were examined with the Iowa Gambling Task in 149 ecstasy-naive subjects. The performance of 59 subjects who initiated ecstasy use during a mean follow-up period of 18 months (range, 11–26) was compared with the performance of 90 subjects that remained ecstasy-naive. Significant differences in decision-making strategy between female future ecstasy users and female persistent ecstasy-naive subjects were found. In addition, the gap between decision-making reaction time after advantageous choices and reaction time after disadvantageous choices was smaller in future ecstasy users than in persistent ecstasy-naives. Decision-making strategy on a gambling task was predictive for future use of ecstasy in female subjects. Differences in decision-making time between future ecstasy users and persistent ecstasy-naives may point to lower punishment sensitivity or higher impulsivity in future ecstasy users. Because differences were small, the clinical relevance is questionable. [ABSTRACT FROM AUTHOR]

Abstract: There is ample evidence for decreased verbal memory in heavy Ecstasy users. However, findings on the presence of a dose–response relation are inconsistent, possibly due to individual differences in genetic vulnerability. Catechol-O-methyltransferase (COMT) is involved in the catabolism of Ecstasy. Therefore, COMT gene polymorphisms may moderate this vulnerability. We prospectively assessed verbal memory in subjects with a high risk for future Ecstasy use, and compared 59 subjects after first Ecstasy use with 60 subjects that remained Ecstasy-naive. In addition, we tested the interaction effect of Ecstasy and the functional val 158met polymorphism on verbal memory. Met-allele carriers were somewhat more sensitive to the effects of Ecstasy on verbal learning than homozygous val-subjects. After correction for the use of other substances this effect was no longer statistically significant. The findings suggest that the COMT gene moderates the negative effect of Ecstasy on memory, but also other drug use seems to play a role. [Copyright &y& Elsevier]

Stress triggers crucial responses, including elevated blood pressure and heart rate (HR), to handle the emergency and restore homeostasis. However, continuation of these effects following cessation of the stress is implicated with many stress-related disorders. Here, we examine the kinetics and persistence of cardiovascular and locomotor responses to single and repeated immobilization stress (IMO), with and without prior treatment with adrenocorticotropic hormone (ACTH). Radiotelemetry probes were implanted into male Sprague-Dawley rats to continually monitor mean arterial pressure (MAP), HR and locomotor activity. Rats were subjected to IMO for 2 h daily (10 a.m. to noon, 6 consecutive days). The first IMO induced the greatest change in MAP (about 30 mm Hg) and HR (about 200 bpm). Following each IMO, MAP and HR were elevated during the remaining light phase and in the subsequent dark phase, HR was lower than prior to IMO. We further examined whether elevation of ACTH to a level similar to IMO will elicit similar effects, and if it will alter subsequent responses to IMO. Injection of ACTH (13 IU/kg, s.c.) triggered a short-lived rise in MAP, and decreased HR. After six daily injections of ACTH and recovery time (8 days), rats were immobilized as above. The cardiovascular responses were similar during the IMO, but the ACTH-pretreated group displayed differences following cessation of the IMO. In addition, IMO led to a large reduction of locomotor activity during the dark (normally active) phase to levels similar to the light phase. Following the IMOs, locomotor activity recovered more slowly in the ACTH-pretreated group. The study revealed that IMO-triggered cardiovascular and locomotor responses are evident after termination of the stress. In addition, prior exposure to ACTH delayed recovery in cardiovascular and locomotor functions following cessation of stress. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The article discusses the conundrum focusing on the barriers of men researching women. It says that views of gender have been widely debunked in the social sciences. It also says that stereotypical beliefs that all women think alike and have universal interests in common have been successfully challenged by feminists who embrace postmodernist, third wave, and queer theory perspectives. However, today, equipped with concepts such as intersectionality and reflexivity, any topic should be open to any researcher, regardless of gender, or race, or sexuality, or any other group identification.

BACKGROUND: A large number of studies, reviews and meta-analyses have reported cognitive deficits in ecstasy users. However most ecstasy users are polydrug users, and therefore it cannot be excluded that these deficits are (partly) the result of drugs other than ecstasy. The current study, part of the Netherlands XTC Toxicity (NeXT) study, investigates the specific sustained effects of ecstasy relative to amphetamine, cocaine and cannabis on the brain using neuropsychological examination. Method: A stratified sample of 67 subjects with such a variation in type and amount of drug use was included that correlations between the consumption of the various drugs were relatively low allowing stepwise linear multiple regression analyses to differentiate between the effects of ecstasy and those of other substances. Subjects were assessed with neuropsychological tests measuring attention, working memory, verbal and visuospatial memory, and visuospatial ability. RESULTS: Ecstasy use [mean 327 (S.D.=364) tablets in lifetime] had a specific significant dose-related negative effect on verbal delayed recall after adjusting for the use of other drugs. CONCLUSIONS: These findings strongly suggest a specific sustained negative effect of ecstasy use on verbal memory. The clinical relevance is not immediately clear, because test performance generally remained within the normal range. However the magnitude of the effect is substantial (d>0.5) and long-term consequences cannot be excluded. [ABSTRACT FROM AUTHOR]

BackgroundA large number of studies, reviews and meta-analyses have reported cognitive deficits in ecstasy users. However most ecstasy users are polydrug users, and therefore it cannot be excluded that these deficits are (partly) the result of drugs other than ecstasy. The current study, part of the Netherlands XTC Toxicity (NeXT) study, investigates the specific sustained effects of ecstasy relative to amphetamine, cocaine and cannabis on the brain using neuropsychological examination.MethodA stratified sample of 67 subjects with such a variation in type and amount of drug use was included that correlations between the consumption of the various drugs were relatively low allowing stepwise linear multiple regression analyses to differentiate between the effects of ecstasy and those of other substances. Subjects were assessed with neuropsychological tests measuring attention, working memory, verbal and visuospatial memory, and visuospatial ability.ResultsEcstasy use [mean 327 (s.d.=364) tablets in lifetime] had a specific significant dose-related negative effect on verbal delayed recall after adjusting for the use of other drugs.ConclusionsThese findings strongly suggest a specific sustained negative effect of ecstasy use on verbal memory. The clinical relevance is not immediately clear, because test performance generally remained within the normal range. However the magnitude of the effect is substantial (d>0.5) and long-term consequences cannot be excluded. [ABSTRACT FROM AUTHOR]

Atmospheric methane is an important greenhouse gas and a sensitive indicator of climate change and millennial-scale temperature variability. Its concentrations over the past 650,000 years have varied between ∼350 and ∼800 parts per 109 by volume (p.p.b.v.) during glacial and interglacial periods, respectively. In comparison, present-day methane levels of ∼1,770 p.p.b.v. have been reported. Insights into the external forcing factors and internal feedbacks controlling atmospheric methane are essential for predicting the methane budget in a warmer world. Here we present a detailed atmospheric methane record from the EPICA Dome C ice core that extends the history of this greenhouse gas to 800,000 yr before present. The average time resolution of the new data is ∼380 yr and permits the identification of orbital and millennial-scale features. Spectral analyses indicate that the long-term variability in atmospheric methane levels is dominated by ∼100,000 yr glacial–interglacial cycles up to ∼400,000 yr ago with an increasing contribution of the precessional component during the four more recent climatic cycles. We suggest that changes in the strength of tropical methane sources and sinks (wetlands, atmospheric oxidation), possibly influenced by changes in monsoon systems and the position of the intertropical convergence zone, controlled the atmospheric methane budget, with an additional source input during major terminations as the retreat of the northern ice sheet allowed higher methane emissions from extending periglacial wetlands. Millennial-scale changes in methane levels identified in our record as being associated with Antarctic isotope maxima events are indicative of ubiquitous millennial-scale temperature variability during the past eight glacial cycles. [ABSTRACT FROM AUTHOR]

A photoacoustic (PA) sensor has been developed to monitor hydrogen chloride at sub-ppm level in the 1740-nm region. The system was designed to control the process in the novel low-water-peak optical fiber manufacturing process. Relaxation effects in hydrogen chloride PA detection in oxygen–helium and nitrogen–helium gas mixtures are presented, showing that the generation of the PA signal is strongly affected by the ratio of these substances. In addition, the role of water vapor in the PA signal is investigated. [ABSTRACT FROM AUTHOR]

This article examines what happens when an employee makes the transition from one recognized gender category to another and remains in the same job. Drawing on in-depth interviews with transmen and transwomen in Texas and California, we illustrate how a new social gender identity is interactionally achieved in these open workplace transitions. While transgender people often are represented as purposefully adopting hyper-feminine or masculine gender identities post-transition, we find that our respondents strive to craft alternative femininities and masculinities. However, regardless of their personal gender ideologies, their men and women co-workers often enlist their transitioning colleague into gender rituals designed to repatriate them into a rigid gender binary. This enlistment limits the political possibilities of making gender trouble in the workplace, as transgender people have little leeway for resistance if they wish to maintain job security and friendly workplace relationships. [ABSTRACT FROM AUTHOR]

The article reviews the film "Drôle de Félix," directed by Jacques Martineau.

Abstract: The development of waterways, for hydropower and other industrial uses, has substantially altered many of the freshwater habitats of the planet and this has had considerable impact upon aquatic organisms. Industrial changes in aquatic ecosystems, including hydropower development, can restrict or delay fish migration, increase predation, affect water quantity and quality, and subject fish to direct damage and stress. This review will focus on the consequences for fish welfare and the progress towards developing the means to pass and protect fish at hydropower dams, at water withdrawal facilities, and in other engineered aquatic environments. It primarily concerns the large mainstem hydropower dams in the Columbia-Snake River Basin in the northwestern United States. Some methods for improving fish passage and protection at hydropower dams involve modifications and additions to engineered structures and occasionally use sensory stimuli such as light, sound, turbulence, or electric fields to influence fish distributions. Measures to improve fish survival, like spilling water at a dam to provide non-turbine passage, can cause other problems for fish, for example higher dissolved gas concentrations downstream. Reducing losses of fish in industrial environments is desirable in both the industrialized world, where many fish-related problems currently exist, and in the developing world, where lessons already learned may make future development more cost-effective and benign. [Copyright &y& Elsevier]

Law faculty in the 21st century present new challenges for law librarians. Traditional services such as document delivery and interlibrary loan are improved. New services are developed to meet the needs of law faculty researching in disciplines other than law and facing a changing environment of publication of legal scholarship. Faculty services in 2000 and 2006 are compared and trends for the future analyzed. [ABSTRACT FROM AUTHOR]

We describe a low-power continuous-wave laser system for water-vapour sensing applications in the 935-nm region. The system is based on extended-cavity diode lasers and distributed-feedback lasers and delivers four single-mode frequency-stabilised optical signals. Three lasers are locked to three water-vapour absorption lines of different strengths, whereas the fourth lies outside any absorption line. On-line stabilisation is performed by wavelength-modulation spectroscopy using compact water-vapour reference cells. An offset-locking technique implemented around an electrical filter is applied for the stabilisation of the off-line slave laser to an on-line master laser at a frequency detuning of 18.8 GHz. Stabilities in the order of 15 MHz over one day were observed for the strongest lines, at the detection limit of the measurement instrumentation. The developed techniques and schemes can be applied to other wavelength ranges and molecular species. Differential absorption lidar instrumentation can in particular benefit from such a system when the stabilised lasers serve as injection seeders to pulsed power oscillators. [ABSTRACT FROM AUTHOR]

Sub-ppm hydrogen chloride (HCl) and water vapour (H2O) monitoring using photoacoustic spectroscopy in optical fibre manufacturing is reported. The development and performance of a sensor based on an acoustic resonant configuration is described, and on-site measurements are presented. Two DFB lasers emitting in the 1370 nm and 1740 nm range were used for the detection of H2O and HCl, respectively. A detection limit (defined for a SNR=3) of 60 ppb for HCl and 40 ppb for H2O was achieved. Contamination sources of the carrier gas used for the fibre preform manufacturing are identified and discussed. [ABSTRACT FROM AUTHOR]

A photoacoustic sensor using a laser diode emitting near 1532 nm in combination with an erbium-doped fibre amplifier has been developed for ammonia trace gas analysis at atmospheric pressure. NH3 concentration measurements down to 6 ppb and a noise-equivalent detection limit below 3 ppb in dry air are demonstrated. Two wavelength-modulation schemes with 1f and 2f detection using a lock-in amplifier were investigated and compared to maximise the signal-to-noise ratio. A quantitative analysis of CO2 and H2O interference with NH3 is presented. Typical concentrations present in ambient air of 400 ppm CO2 and 1.15% H2O (50% relative humidity at 20 °C) result in a NH3 equivalent concentration of 36 ppb and 100 ppb, respectively. [ABSTRACT FROM AUTHOR]