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Beaulieu J, Yates MC, Astorg L, Trépanier-Leroux D, Jeon H, Rudko SP, Humphries S, Fraser DJ, Cristescu ME, Derry AM. 2024. Environmental DNA for assessing impact and recovery of aquatic communities in an invaded mountain lake. Lake Reserv Manage. 40:111–131. The eradication of invasive species and associated side effects that influence the reestablishment of biological communities is a major challenge for conservation management of invaded ecosystems. We present a before-and-after-disturbance whole lake manipulation study from a high-elevation mountain lake in which we applied a 2-pronged approach to environmental DNA (eDNA) for assessing (1) impact and recovery of aquatic communities to the chemical eradication of invasive brook trout (Salvelinus fontinalis) and (2) the success of chemical eradication of the invasive fish. Using 18S and cytochrome oxidase I (COI) eDNA metabarcoding, we contribute to a paucity of literature that has comprehensively addressed nontarget effects of rotenone for invasive fish eradication on aquatic communities. We found that key trophic groups (phytoplankton, fungi, zooplankton, and macroinvertebrates) changed in community composition in response to rotenone applications. Fungi and macroinvertebrates, but not zooplankton and phytoplankton, reverted back toward pre-rotenone communities over the time scale of 2 yr. However, COI failed to detect several key species for food web reestablishment that were detected using physical specimen collection, likely due to low primer efficiency. We also found that quantitative polymerase chain reaction (qPCR), using species-specific primers, was effective for detecting brook trout presence/absence, although strong eDNA signals likely produced from carcasses in the ecosystem limited the utility of eDNA immediately following rotenone treatment. We provide specific recommendations for lake managers for the future application of eDNA approaches to monitor invasive fish eradication efforts and nontarget community effects for lake ecosystem restoration. [ABSTRACT FROM AUTHOR]

Beaulieu J, Trépanier-Leroux D, Fischer JM, Olson MH, Thibodeau S, Humphries S, Fraser DJ, Derry AM. 2021. Rotenone for exotic trout eradication: nontarget impacts on aquatic communities in a mountain lake. Lake Reserv Manage. 37:323–338. Rotenone is widely used in lake and reservoir management for the eradication of exotic fish. However, nontarget effects of rotenone on freshwater organisms such as zooplankton and macroinvertebrates are of concern because of the ecological importance of these organisms in aquatic food webs as a resource base for fish, especially when rotenone is applied to lakes prior to native fish reintroduction. The objective of our study was to determine the effects of rotenone on nontarget zooplankton and macroinvertebrate species assemblages in a headwater mountain lake where rotenone was applied to remove exotic brook trout (Salvelinus fontinalis; Banff, AB Canada). We found strong negative rotenone impacts on the community structure and density of crustacean zooplankton, and to a lesser extent on macroinvertebrates, lasting for at least 1 yr after the rotenone treatment. Our study offers 2 unique insights that differentiate from rotenone studies on other lakes: (1) the persistent and almost complete eradication of crustacean zooplankton in the following summers, 11 months after rotenone treatment, and (2) a considerable shift in the macroinvertebrate community composition, likely resulting from combined effects of both nontarget rotenone effects on taxon density and trophic interactions associated with the eradication of brook trout from the lake. We advocate that assisted recolonization in the restoration of aquatic food webs could play an important role in facilitating nontarget aquatic community recovery following lake rotenone treatment. [ABSTRACT FROM AUTHOR]

Abstract: We conduct a novel comprehensive investigation that seeks to prove the connection between spatial scales and timescales in surface soil moisture (SM) within the satellite footprint (~50 km). Modeled and measured point series at Yanco and Little Washita in situ networks are first decomposed into anomalies at timescales ranging from 0.5 to 128 days, using wavelet transforms. Then, their degree of spatial representativeness is evaluated on a per‐timescale basis by comparison to large spatial scale data sets (the in situ spatial average, SMOS, AMSR2, and ECMWF). Four methods are used for this: temporal stability analysis (TStab), triple collocation (TC), percentage of correlated areas (CArea), and a new proposed approach that uses wavelet‐based correlations (WCor). We found that the mean of the spatial representativeness values tends to increase with the timescale but so does their dispersion. Locations exhibit poor spatial representativeness at scales below 4 days, while either very good or poor representativeness at seasonal scales. Regarding the methods, TStab cannot be applied to the anomaly series due to their multiple zero‐crossings, and TC is suitable for week and month scales but not for other scales where data set cross‐correlations are found low. In contrast, WCor and CArea give consistent results at all timescales. WCor is less sensitive to the spatial sampling density, so it is a robust method that can be applied to sparse networks (one station per footprint). These results are promising to improve the validation and downscaling of satellite SM series and the optimization of SM networks. [ABSTRACT FROM AUTHOR]

Background Constitutional mismatch repair deficiency (CMMRD) syndrome is a childhood cancer predisposition syndrome involving biallelic germline mutations of MMR genes, poorly recognised by clinicians so far. Methods Retrospective review of all 31 patients with CMMRD diagnosed in French genetics laboratories in order to describe the characteristics, treatment and outcome of the malignancies and biological diagnostic data. Results 67 tumours were diagnosed in 31 patients, 25 (37%) Lynch syndrome-associated malignancies, 22 (33%) brain tumours, 17 (25%) haematological malignancies and 3 (5%) sarcomas. The median age of onset of the first tumour was 6.9 years (1.2-33.5). Overall, 22 patients died, 9 (41%) due to the primary tumour. Median survival after the diagnosis of the primary tumour was 27 months (0.26-213.2). Failure rate seemed to be higher than expected especially for T-cell non-Hodgkin's lymphoma (progression/relapse in 6/12 patients). A familial history of Lynch syndrome was identified in 6/23 families, and consanguinity in 9/23 families. PMS2 mutations (n=18) were more frequent than other mutations (MSH6 (n=6), MLH1 (n=4) and MSH2 (n=3)). Conclusions In conclusion, this unselected series of patients confirms the extreme severity of this syndrome with a high mortality rate mostly related to multiple childhood cancers, and highlights the need for its early detection in order to adapt treatment and surveillance. [ABSTRACT FROM AUTHOR]

Introduction: Although a number of studies look at prevalence, incidence, treatment, mortality and morbidity in relation to hypertension, few have taken into account the effect of residential neighbourhood on these health indicators in the population diagnosed with hypertension. Objectives: The objective of this study was to measure and compare prevalence, mortality, morbidity, use of medical resources and treatments in relation to the level of material and social deprivation of the area of residence, in a population with a diagnosis of hypertension in primary prevention for cardiovascular disease (CVD) in Quebec in 2006-2007. Methods: This study is based on a secondary analysis of the medical administrative data of the Quebec health insurance board, the Régie de l'assurance maladie du Québec, for a cohort of 276 793 patients aged 30 years or older who had been diagnosed with hypertension in 2006 or 2007, but who did not have a known diagnosis of CVD. The health indicators adjusted for age and sex are prevalence, death, a cardiovascular event, physician visits, emergency department visits and use of antihypertensives. Twenty-five types of areas of residence were obtained by crossing the material and social deprivation quintiles. Results: Compared with patients living in materially and socially advantaged areas, those living in deprived areas were at 46% higher risk of a cardiovascular event, 47% higher risk of being frequent emergency department visitors and 31% higher risk of being frequent users of a general practitioner's services, but 25% lower risk of being frequent users of medical specialists' services. Little or no variation was observed in the use of antihypertensives. Conclusion: This study reveals the existence, in a CVD primary prevention context, of large variations in a number of health indicators among hypertensive patients owing to the material and social deprivation of residential neighbourhood. It is therefore important to take the socioeconomic context into account when planning interventions to prevent CVDs and their consequences. [ABSTRACT FROM AUTHOR]

The Soil Moisture and Ocean Salinity (SMOS) satellite has opened the era of soil moisture products from passive L-band observations. In this paper, validation of SMOS products over continental U.S. is done by using the Soil Climate Analysis Network (SCAN)/SNOwpack TELemetry (SNOTEL) soil moisture monitoring stations. The SMOS operational products and the SMOS reprocessing products are both used and compared over year 2010. First, a direct node-to-site comparison is performed by taking advantage of the oversampling of the SMOS product grid. The comparison is performed over several adjacent nodes to site, and several representative couples of site-node are identified. The impact of forest fraction is shown through the analysis of different cases across the U.S. Also, the impact of water fraction is shown through two examples in Florida and in Utah close to Great Salt Lake. A radiometric aggregation approach based on the antenna footprint and spatial description is used. A global comparison of the SCAN/SNOTEL versus SMOS is made. Statistics show an underestimation of the soil moisture from SMOS compared to the SCAN/SNOTEL local measurements. The results suggest that SMOS meets the mission requirement of 0.04 m3/m3 over specific nominal cases, but differences are observed over many sites and need to be addressed. [ABSTRACT FROM AUTHOR]

The Soil Moisture and Ocean Salinity (SMOS) mission is European Space Agency (ESA's) second Earth Explorer Opportunity mission, launched in November 2009. It is a joint program between ESA Centre National d'Etudes Spatiales (CNES) and Centro para el Desarrollo Tecnologico Industrial. SMOS carries a single payload, an L-Band 2-D interferometric radiometer in the 1400-1427 MHz protected band. This wavelength penetrates well through the atmosphere, and hence the instrument probes the earth surface emissivity. Surface emissivity can then be related to the moisture content in the first few centimeters of soil, and, after some surface roughness and temperature corrections, to the sea surface salinity over ocean. The goal of the level 2 algorithm is thus to deliver global soil moisture (SM) maps with a desired accuracy of 0.04 m3/m3. To reach this goal, a retrieval algorithm was developed and implemented in the ground segment which processes level 1 to level 2 data. Level 1 consists mainly of angular brightness temperatures (TB), while level 2 consists of geophysical products in swath mode, i.e., as acquired by the sensor during a half orbit from pole to pole. In this context, a group of institutes prepared the SMOS algorithm theoretical basis documents to be used to produce the operational algorithm. The principle of the SM retrieval algorithm is based on an iterative approach which aims at minimizing a cost function. The main component of the cost function is given by the sum of the squared weighted differences between measured and modeled TB data, for a variety of incidence angles. The algorithm finds the best set of the parameters, e.g., SM and vegetation characteristics, which drive the direct TB model and minimizes the cost function. The end user Level 2 SM product contains SM, vegetation opacity, and estimated dielectric constant of any surface, TB computed at 42.5°, flags and quality indices, and other parameters of interest. This paper gives an overview of the algorithm, discusses the caveats, and provides a glimpse of the Cal Val exercises. [ABSTRACT FROM AUTHOR]

Estimation of soil moisture at large scale has been performed using several satellite-based passive microwave sensors and a variety of retrieval methods over the past two decades. The most recent source of soil moisture is the European Space Agency Soil Moisture and Ocean Salinity (SMOS) mission. A thorough validation must be conducted to insure product quality that will, in turn, support the widespread utilization of the data. This is especially important since SMOS utilizes a new sensor technology and is the first passive L-band system in routine operation. In this paper, we contribute to the validation of SMOS using a set of four in situ soil moisture networks located in the U.S. These ground-based observations are combined with retrievals based on another satellite sensor, the Advanced Microwave Scanning Radiometer (AMSR-E). The watershed sites are highly reliable and address scaling with replicate sampling. Results of the validation analysis indicate that the SMOS soil moisture estimates are approaching the level of performance anticipated, based on comparisons with the in situ data and AMSR-E retrievals. The overall root-mean-square error of the SMOS soil moisture estimates is 0.043 m3/m3 for the watershed networks (ascending). There are bias issues at some sites that need to be addressed, as well as some outlier responses. Additional statistical metrics were also considered. Analyses indicated that active or recent rainfall can contribute to interpretation problems when assessing algorithm performance, which is related to the contributing depth of the satellite sensor. Using a precipitation flag can improve the performance. An investigation of the vegetation optical depth (tau) retrievals provided by the SMOS algorithm indicated that, for the watershed sites, these are not a reliable source of information about the vegetation canopy. The SMOS algorithms will continue to be refined as feedback from validation is evaluated, and it is expected that the SMOS estimates will improve. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which is about t-positive B-cell malignancy in atypical chronic lymphocytic leukemia.

A new space-time block code family for two transmitters, called the space-time error correcting codes (STECCs), is presented. As it is built from any linear forward error correcting code (FEC), a STECC is able to correct errors while achieving high spectral efficiencies. The key principle is the FEC linearity which is exploited to transmit linear combinations of FEC codewords to create a space-time redundancy. The proposed code exhibits interesting performance on an ISI-free block fading channel. This result is all the more true as the number of FEC codewords considered in the combination is high. [ABSTRACT FROM PUBLISHER]

Recently, we and others have described a novel class of chromosome aberrations that involves constitutive heterochromatin on human chromosome 1 (cytogenetic band 1q12). These anomalies are particularly frequent in B cell non-Hodgkins lymphoma (NHL) and multiple myeloma (MM) and, remarkably, almost invariably involve partial or total gain of chromosome 1q (including 1q12 heterochromatin) and the formation of novel heterochromatin/euchromatin junctions. This review discusses the pathological significance of these anomalies in light of i) recent integrated gene expression and array comparative genomic hybridisation (aCGH) profiling in MM and ii) increasing evidence of a key role for heterochromatin in the control of normal and pathological gene silencing. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

This paper deals with a low complexity receiver scheme where equalization and channel decoding are jointly optimized in an iterative process. We derive the theoretical transfer function of the infinite length linear minimum mean square error (MMSE) equalizer with a priori information. A practical implementation is exposed which employs the fast Fourier transform (FFT) to compute the equalizer coefficients, resulting in a low-complexity receiver structure. The performance of the proposed scheme is investigated for the enhanced general packet radio service (EGPRS) radio link. Simulation results show that significant power gains may be achieved with only a few (3-4) iterations. These results demonstrate that MMSE turbo equalization is an attractive candidate for single-carrier broadband wireless transmissions in long delay-spread environments. [ABSTRACT FROM PUBLISHER]

Fluorescence in situ hybridization (FISH) on interphase nuclei has been shown to be an efficient method for detecting aneuploidy in multiple myeloma (MM). The aim of this study was to test the feasibility of FISH techniques for detecting malignant cells in the harvests of MM patients submitted to autologous transplantation. As trisomy 9 (T9) is a frequent event in MM, we used it as a genetic marker of malignant plasma cells. T9 was detected in 45 out of 55 MM bone marrow samples (81.8%) using a chromosome 9 centromeric (C9C) probe. Twenty-four of the 55 MM patients were subjected to high-dose therapy followed by autologous unselected progenitor cell transplantation. Trisomy 9 was detected in 20 patients and was used as a marker of malignant cells. Upon karyotypic analysis, three of the four remaining patients without T9 showed an unbalanced translocation leading to a complete trisomy of the long arm of chromosome 1 (T1q). We thus used a 1q juxtacentromeric probe, pUC1.77, as another genetic marker of malignant plasma cells in these three further patients. FISH with C9C or pUC1.77 probes was performed on the harvests of these 23 patients and detected clonal cells in 11 transplants. The disease-free survival from graft was significantly longer for the patients who had no malignant cells in their transplant (P = 0.009). The median disease-free survival was 23 months in these patients, as compared to 12 months in the patients whose transplant was contaminated. As almost all MM are cytogenetically abnormal, FISH with adequate probes represents a simple, quantitative tool for rapid detection of malignant cells in the harvests. Our results also suggest that the presence of MM cells in the transplant may be predictive of poor outcome. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor about the the biosynthesis of human leukocyte antigen published in the 2004 issue of "Leukemia."