Does degradation from selective logging and illegal activities differently impact forest resources? A case study in Ghana

Degradation, a reduction of the ecosystem’s capacity to supply goods and services, is widespread in tropical forests and mainly caused by human disturbance. To maintain the full range of forest ecosystem services and support the development of effective conservation policies, we must understand the overall impact of degradation on different forest resources. This research investigates the response to disturbance of forest structure using several indicators: soil carbon content, arboreal richness and biodiversity, functional composition (guild and wood density), and productivity. We drew upon large field and remote sensing datasets from different forest types in Ghana, characterized by varied protection status, to investigate impacts of selective logging, and of illegal land use and resources extraction, which are the main disturbance causes in West Africa. Results indicate that functional composition and the overall number of species are less affected by degradation, while forest structure, soil carbon content and species abundance are seriously impacted, with resources distribution reflecting the protection level of the areas. Remote sensing analysis showed an increase in productivity in the last three decades, with higher resiliency to change in drier forest types, and stronger productivity correlation with solar radiation in the short dry season. The study region is affected by growing anthropogenic pressure on natural resources and by an increased climate variability: possible interactions of disturbance with climate are also discussed, together with the urgency to reduce degradation in order to preserve the full range of ecosystem functions

Early mapping of industrial tomato in Central and Southern Italy with Sentinel 2, aerial and RapidEye additional data

Timely crop information, i.e. well before harvesting time and at first stages of crop development, can benefit farmers and producer organizations. The current case study documents the procedure to deliver early data on planted tomato to users, showing the potential of Sentinel 2 to map tomato at the very beginning of the crop season, which is a challenging task. Using satellite data, integrated with ground and aerial data, an initial estimate of area planted with tomato and early tomato maps were generated in seven main production areas in Italy. Estimates of the amount of area planted with tomato provided similar results either when derived from field surveys or from remote sensing-based classification. Tomato early maps showed a producer accuracy > 80% in seven cases out of nine, and a user accuracy > 80% in five cases out of nine, with differences attributed to the varying agricultural characteristics and environmental heterogeneity of the study areas. The additional use of aerial data improved producer accuracy moderately. The ability to identify abrupt growth changes, such as those caused by natural hazards, was also analysed: Sentinel 2 detected significant changes in tomato growth between a hailstorm-affected area and a control area. The study suggests that Sentinel 2, with enhanced spectral capabilities and open data policy, represents very valuable data, allowing crop monitoring at an early development stage

Role of cardiac troponin I phosphorylation in cardiac function: From molecule to mouse

Abstract only availableThe regulation of cardiac muscle contraction involves the interplay between a variety of molecules on the thick and thin filaments. One important regulatory molecule is troponin, which consists of three subunits, troponin C (TnC) that binds calcium, troponin T (TnT) that binds tropomyosin, and troponin I (TnI) that binds actin and tends to inhibit contraction. Following muscle excitation, cytoplasmic calcium rises and binds TnC, which causes a conformational change in TnI that reduces its affinity for actin; this, in turn, allows TnT and tropomyosin to shift positions revealing myosin binding sites on actin, leading to muscle contraction. Interestingly, cardiac troponin I (cTnI) has several phosphorylation sites, which are known to modulate this regulatory process. For example, phosphorylation of serines 23 and 24 on cTnI by protein kinase A (PKA) is known to decrease the calcium binding affinity of cardiac TnC and, thus, thought to speed muscle relaxation. On the other hand, phosphorylation of cTnI on serines 43 and 45 and threonine 144 by protein kinase C (PKC) decreases both force production and calcium sensitivity of force and is thought to contribute to depressed ventricular function in failing hearts. In this study we investigated the effects of chronic cTnI phosphorylation on cardiac function from transgenic animals in which either PKA phosphorylation sites (Ser-23/Ser-24) (PP) or both the PKA and PKC phosphorylation sites (Ser-23/Ser-24/Ser-43/Ser-45/T-144) (All-P) were replaced with aspartic acid to mimic phosphorylation. Left ventricular cardiac myocytes from PP transgenic mice exhibited less calcium sensitivity of force while myocytes from All-P transgenic mice exhibited decreased maximal force, decreased calcium sensitivity of force, and decreased power output, implicating a dominate role of PKC phosphorylation sites on myofilament function. Consistent with these single myocyte studies, left ventricular power output also was depressed in All-P mice compared to both WT and PP transgenic ventricles. We next tested the hypothesis that PP transgenic mice would engage in greater voluntary running compared to WT and All-P transgenic animals. In contrast to this idea, WT and All-P mice ran ~3- and ~4-fold more than the PP transgenic mouse, respectively. Overall, these results indicate that PKC phosphorylation of cTnI plays a dominant role in depressing contractility and may contribute to the maladaptive behavior.NIH grant to K.S. McDonal

Structural Measures for Network Biology Using QuACN

Background: Structural measures for networks have been extensively developed, but many of them have not yet demonstrated their sustainably. That means, it remains often unclear whether a particular measure is useful and feasible to solve a particular problem in network biology. Exemplarily, the classification of complex biological networks can be named, for which structural measures are used leading to a minimal classification error. Hence, there is a strong need to provide freely available software packages to calculate and demonstrate the appropriate usage of structural graph measures in network biology. Results: Here, we discuss topological network descriptors that are implemented in the R-package QuACN and demonstrate their behavior and characteristics by applying them to a set of example graphs. Moreover, we show a representative application to illustrate their capabilities for classifying biological networks. In particular, we infer gene regulatory networks from microarray data and classify them by methods provided by QuACN. Note that QuACN is the first freely available software written in R containing a large number of structural graph measures. Conclusion: The R package QuACN is under ongoing development and we add promising groups of topological network descriptors continuously. The package can be used to answer intriguing research questions in network biology, e.g., classifying biological data or identifying meaningful biological features, by analyzing the topology o

Aboveground forest biomass estimation with Landsat and LiDAR data and uncertainty analysis of the estimates.

Landsat Thematic mapper (TM) image has long been the dominate data source, and recently LiDAR has offered an important new structural data stream for forest biomass estimations. On the other hand, forest biomass uncertainty analysis research has only recently obtained sufficient attention due to the difficulty in collecting reference data. This paper provides a brief overview of current forest biomass estimation methods using both TM and LiDAR data. A case study is then presented that demonstrates the forest biomass estimation methods and uncertainty analysis. Results indicate that Landsat TM data can provide adequate biomass estimates for secondary succession but are not suitable for mature forest biomass estimates due to data saturation problems. LiDAR can overcome TM?s shortcoming providing better biomass estimation performance but has not been extensively applied in practice due to data availability constraints. The uncertainty analysis indicates that various sources affect the performance of forest biomass/carbon estimation. With that said, the clear dominate sources of uncertainty are the variation of input sample plot data and data saturation problem related to optical sensors. A possible solution to increasing the confidence in forest biomass estimates is to integrate the strengths of multisensor data

COSMO-SkyMed potential to detect and monitor Mediterranean maquis fires and regrowth: a pilot study in Capo Figari, Sardinia, Italy

Mediterranean maquis is a complex and widespread ecosystem in the region, intrinsically prone to fire. Many species have developed specific adaptation traits to cope with fire, ensuring resistance and resilience. Due to the recent changes in socio-economy and land uses, fires are more and more frequent in the urban-rural fringe and in the coastlines, both now densely populated. The detection of fires and the monitoring of vegetation regrowth is thus of primary interest for local management and for understanding the ecosystem dynamics and processes, also in the light of the recurrent droughts induced by climate change. Among the main objectives of the COSMO-SkyMed radar constellation mission there is the monitoring of environmental hazards; the very high revisiting time of this mission is optimal for post-hazard response activities. However, very few studies exploited such data for fire and vegetation monitoring. In this research, Cosmo-SkyMed is used in a Mediterranean protected area covered by maquis to detect the burnt area extension and to conduct a mid-term assessment of vegetation regrowth. The positive results obtained in this research highlight the importance of the very high-resolution continuous acquisitions and the multi-polarization information provided by COSMO-SkyMed for monitoring fire impacts on vegetation

Variational nodal perturbation calculations using simplified spherical harmonics

The simplified spherical harmonics (SP{sub N}) method has been used as an approximation to the transport equation in a number of situations. Recently, the SP{sub N} method has been formulated within the framework of the variational nodal method (VNM). Implementation in the VARIANT code indicated that for many two and three dimensional problems, near P{sub N} accuracy can be obtained at a fraction of the Cost. Perturbation methods offer additional computational cost reduction for reactor core calculations and are indispensable for performing a variety of calculations including sensitivity studies and the breakdown by components of reactivity worths. Here, we extend the perturbation method developed for the VNM in the full P{sub N} approximation to treat simplified spherical harmonics. The change in reactivity predicted by both first order and exact perturbation theory using the SP{sub N} approximation is demonstrated for a benchmark problem and compared to diffusion and full P{sub N} estimates

Anti-series varactor network with improved linearity performances in the presence of inductive and capacitive parasitics

ABSTRACT: This paper proposes a varactor-based circuit technique intended for amplitude and phase control, with improved linearity in the presence of parasitic capacitances and parasitic inductances. The mechanism causing linearity degradation in an anti-series varactor network that includes significant parasitic elements - a key aspect that, to our knowledge, has never been reported - is first studied using an analytical approach based on multi-tone excitation. It is demonstrated that simply optimizing the ratio of diode sizes is insufficient to circumvent this linearity degradation. The underlying linearity degradation concept serves as the basis for the introduction of a modified anti-series controllable capacitance, followed by a design and practical implementation. Experimental validations with multi-tone and modulated signals demonstrate improved linearity performances with respect to the state-of-the-art when parasitic capacitances and inductances are significant. Moreover, it is shown that the complete varactor-based circuit topology proposed here, which uses the proposed modified anti-series controllable capacitance in conjunction with a second-harmonic trap filter, constitutes a very attractive alternative to the state-of-the-art anti-series/anti-parallel topology, since it reduces the required number of diodes by a factor of 2. Measurements on discrete-component designs operating at 3.6GHz, hence with significant parasitic effects, demonstrate that the proposed circuit topology improves the 3 rd order intermodulation distortion levels by 10.6dB and 6.6dB at output powers of 10dBm and 18dBm respectively, in comparison with the state-of-the-art topology. Measurements with a 16QAM modulated signal also show 3.9dB improvement in ACPR at 18dBm. These performances constitute improved state-of-the-art results in anti-series hyper-abrupt varactor-based electronic control

Geological relationships and laser ablation ICP-MS U-Pb geochronology of the Saint George Batholith, southwestern New Brunswick, Canada: implications for its tectonomagmatic evolution

  The Late Silurian to Late Devonian Saint George Batholith in southwestern New Brunswick is a large composite intrusion (2000 km2) emplaced into the continental margin of the peri-Gondwanan microcontinent of Ganderia. The batholith includes: (1) Bocabec Gabbro; (2) equigranular Utopia and Wellington Lake biotite granites; (3) Welsford, Jake Lee Mountain, and Parks Brook peralkaline granites; (4) two-mica John Lee Brook Granite; (6) Jimmy Hill and Magaguadavic megacrystic granites; and (6) rapakivi Mount Douglas Granite. New LA ICP-MS in situ analyses of six samples from the Saint George Batholith are as follows: (1) U-Pb monazite crystallization age of 425.5 ± 2.1 Ma for the Utopia Granite in the western part of the batholith (2) U-Pb zircon crystallization ages of 420.4 ± 2.4 Ma and 420.0 ± 3.5 Ma for two samples of the Utopia Granite from the central part of the batholith; (3) U-Pb zircon crystallization age of 418.0 ± 2.3 Ma for the Jake Lee Mountain Granite; (4) U-Pb zircon crystallization age of 415.5 ± 2.1 Ma for the Wellington Lake Granite; and (5) U-Pb monazite crystallization age of 413.3 ± 2.1 Ma for the John Lee Brook Granite. The new geochronological together with new and existing geochemical data suggest that the protracted magmatic evolution of the Late Silurian to Early Devonian plutonic rocks is related to the transition of the Silurian Kingston arc-Mascarene backarc system from an extensional to compressional tectonic environment during collision of the Avalonian microcontinent with Laurentia followed by slab break-off.