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11.
Recent advances in sensor development and miniaturization offer new possibilities to monitor and control bioprocesses. Specific requirements for anaerobic processes in terms of low costs and high robustness against insoluble fractions and impurities in media led to a decelerated penetration of new technology in this field. Since no regulatory framework demands for process monitoring and documentation like in the pharmaceutical industry, the implementation of new sensors beyond long-established methods is not conducted as intensively.Nevertheless, many attempts have been made in recent years to adopt sensors and show their applicability in anaerobic fermentation processes. New possibilities arise for improved monitoring, control and faster process development through digitalization. This review aims to provide an overview over these recent attempts with the focus on the liquid phase in the upstream part of pure culture bioprocesses for anaerobic bulk compound, food, and beverage production. In particular, methods that monitor the viability, metabolic activity or related parameters are discussed, like electrochemical, impedance and spectroscopy probes, and methods related to fluid flow and gradient formation, like acoustic and mobile sensors.  相似文献   
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许多长距离迁徙的雀形目鸟类的种群数量正在持续下降,田鹀(Emberiza rustica)种群数量下降趋势更为突出。通过对田鹀种群数量长期监测和迁徙动态分析,可为此物种保护提供科学依据。从2001年开始,陆续在黑龙江省高峰、青峰、帽儿山、新青和大沾河,吉林省珲春和吉林市,辽宁省的辽宁鸟类研究中心(大连)和旅顺老铁山,以及内蒙古乌尔其汗鸟类栖息的临水林缘处布网环志。截至2018年,累计环志田鹀184181只,其中春季88571只,秋季95610只;各年度环志数量波动较大,总体呈现急速下降趋势。幼鸟的越冬损失率高达41.3%。田鹀106只次的回收信息表明,自然条件下田鹀寿命可达11年以上;日迁飞距离最快可达到300 km,飞行速度可达30 km/h。中国东北地区是田鹀等鸟类的重要迁徙途经地;田鹀的迁徙路线相对稳定,在瑞典北部繁殖的种群经中国东北地区迁徙到天津以南越冬。通过环志发现,近些年田鹀种群数量急速下降。通过比对,发现中国东北地区田鹀的环志数量变化趋势与瑞典的田鹀环志数量变化趋势相似;相对于环志数量最多的年份,环志数量下降95%以上,值得关注。栖息地破碎化、非法猎捕等是影响田鹀生存的主要受威胁因素。建议依据田鹀等鸟类生物学习性,加强鸟类栖息地的保护,坚持长期标准化的鸟类环志监测,进一步探索鸟类迁徙规律,以助于鸟类种群的恢复。  相似文献   
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Background:

Least Significant Change (LSC) assists in determining whether observed bone change is beyond measurement precision. Monitoring Time Interval (MTI) estimates time required to reliably detect skeletal changes. MTIs have not been defined for bone outcomes provided by high resolution peripheral quantitative computed tomography (HR-pQCT). The purpose of this study was to determine the LSCs and MTIs for HR-pQCT derived bone area, density and micro-architecture with postmenopausal women.

Methods:

Distal radius and tibia of 33 postmenopausal women (mean age: 77, SD: ±7 years), from the Saskatoon cohort of the Canadian Multicentre Osteoporosis Study (CaMos), were measured using HR-pQCT at baseline and 1-year later. We determined LSC from precision errors and divided them by the median annual percent changes to define MTIs for bone area, density, and micro-architecture.

Results:

Distal radius: HR-pQCT LSCs indicated a 1-8% observed change was needed for reliable monitoring of bone area and density while a 3-18% change was needed for micro-architectural measures. The longest MTIs (>3 years) pertained to cortical and trabecular area and density measures, cortical thickness and bone volume fraction; the shortest MTIs (~2 years) pertained to bone micro-architectural measures (trabecular number, thickness, separation and heterogeneity). Distal tibia: LSCs indicated a <1-5% observed change was needed for reliable monitoring of bone area and density, while a 3-19% change was needed for micro-architectural measures. The longest MTIs (>3 years) pertained to trabecular density, bone volume fraction, number, separation and heterogeneity; the shortest MTIs (~1 year) pertained to cortical and trabecular area, cortical density and thickness.

Conclusion:

MTIs suggest that performing HR-pQCT follow-up measures in postmenopausal women every 2 years at the distal radius and every 1 year at the distal tibia to monitor true skeletal changes as indicated by the LSCs.  相似文献   
15.
Within the scope of a seagrass monitoring program in the Novigrad Sea, Central Croatian Adriatic, we predicted that the annual variability in coverage of seagrasses (Zostera marina, Zostera noltii, and Cymodocea nodosa) can be partially explained by the annual variability in sediment translocation. From 23 fixed DGPS-referenced monitoring video transects followed over three years (June 2007-2009), we calculated annual (i) changes in interior bed seagrass coverage, (ii) gain in seagrass at the lower edge of the bed and seagrass bed expansion, and (iii) accumulation of sediment, its depth dependence, and the associated changes in transect slope. We found that in 2007 to 2008, the year with net sediment accumulation, seagrass coverage increased and the bed expanded. In both years seagrass cover within the seagrass bed increased with increasing sediment accumulation, while seagrass bed expansion was highest under intermediate sedimentation rates. Boat-based videographic monitoring can document both natural sediment movement along the depth gradient, and species-specific responses necessary for informed management of submerged aquatic vegetation in the Adriatic Sea.  相似文献   
16.
Differences in the accumulation of seven metallic elements, including micronutrients (Cu, Fe, Mn, Ni and Zn) and non-essential elements (Cd and Pb) among plant organs (leaves, roots and rhizomes) were examined in the seagrass Cymodocea nodosa. Samples were taken from two coastal bays (Catalonia, Western Mediterranean), with a total of nine sampling sites encompassing different levels of metal availability. Metal content was generally higher in uptake organs (leaves and roots) than in rhizomes. However, accumulation in leaves and roots varied between elements. While Cd, Mn and Zn preferentially accumulate in leaves, Fe and Pb accumulate in roots and Cu and Ni in both. There were common spatial (between sites) trends in Cd, Mn, Cu and Zn accumulation in the three organs. However, these spatial trends varied according to the organ considered in the case of Fe, Pb, and Ni. Therefore, assessment of within-plant variability is strongly recommended prior to the use of C. nodosa for biomonitoring purposes, at least for Fe, Pb, and Ni.  相似文献   
17.
Road ecology, the study of the impacts of roads and their traffic on wildlife, including birds, is a rapidly growing field, with research showing effects on local avian population densities up to several kilometres from a road. However, in most studies, the effects of roads on the detectability of birds by surveyors are not accounted for. This could be a significant source of error in estimates of the impacts of roads on birds and could also affect other studies of bird populations. Using road density, traffic volume and bird count data from across Great Britain, we assess the relationships between roads and detectability of a range of bird species. Of 51 species analysed, the detectability of 36 was significantly associated with road exposure, in most cases inversely. Across the range of road exposure recorded for each species, the mean positive change in detectability was 52% and the mean negative change was 36%, with the strongest negative associations found in smaller-bodied species and those for which aural cues are more important in detection. These associations between road exposure and detectability could be caused by a reduction in surveyors’ abilities to hear birds or by changes in birds’ behaviour, making them harder or easier to detect. We suggest that future studies of the impacts of roads on populations of birds or other taxa, and other studies using survey data from road-exposed areas, should account for the potential impacts of roads on detectability.  相似文献   
18.
A sound monitoring of appropriate biodiversity indicators is necessary in order to assess the progress towards the internationally agreed target of halting the loss of biodiversity by 2010. However, existing monitoring schemes often do not address species richness as a key component of biodiversity directly or do so with insufficient methods. I provide an overview and assessment of the large variety of different sampling approaches for small-scale plant species richness. Major shortcomings of many of these are (i) non-uniform plot sizes or shapes; (ii) analysis of only one spatial scale despite the scale dependence of nearly all biodiversity parameters; (iii) lack of replication of smaller subplots; and (iv) exclusion of bryophytes and lichens despite their often large contribution to total plant diversity. Based on this review, I propose a new standardised sampling approach for plant diversity patterns at small scales that is applicable for a multitude of purposes and in any biome. In its basic variant, species composition is recorded on nested squares of 0.01 m2, 0.1 m2, 1 m2, 10 m2, and 100 m2, with all smaller subplots being replicated at least 3-fold and evenly spaced within the next larger plot. Not only terricolous vascular plants, but also bryophytes, lichens, macro-algae as well as non-terricolous taxa should be recorded with the any-part system, i.e. those plants are counted within a plot whose superficial parts reach over it. This approach can be used to assess plant diversity patterns (i) of individual plots of interest, (ii) along environmental gradients, (iii) within specific vegetation types, or (iv) for landscape sectors. In the latter case, the series of nested plots must be placed randomly or systematically, but irrespective of plot homogeneity. The proposed approach allows the calculation of many meaningful biodiversity indicators, while being well compatible with a range of other sampling schemes, but avoiding their shortcomings. As this approach is not very time-consuming in its basic variant, but can easily be extended for specific purposes, I suggest its use for any kind of biodiversity studies and particularly for monitoring.  相似文献   
19.
The case of the Northern spotted owl (Strix occidentalis caurina) has now become a classic case study in conservation biology, characterized by a harsh social battle but also by the quantity and quality of the research performed. Based on this example, I study the way the research-management interface was organized. The main lessons I have learned were: 1. laws that involve science in management are crucial but should be more precise; 2. scientific ad-hoc groups are useful reviewers of management plans and interpreters of the best scientific data available, even if more transparent scientific argumentation is needed on some points; 3. in such applied cases, even science that has not been strongly integrated with management can produce results that are useful for management; 4. stronger links between science and management appear necessary, but difficult to implement. This last point makes me wonder whether environmental laws should not more frequently target the incorporation of science into the management process itself rather than “only” basing management on the best scientific data available. On a more ecological level, perhaps the habitat issue has been underrated during the last few years compared to other emerging threats such as the invasion of the spotted owl range by barred owls.  相似文献   
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