•Wine grape clusters can be successfully detected, segmented and tracked using CNNs.•Mask R-CNN has reached a 0.91 F1-score for grape segmentation in our dataset.•Grape clusters can be successfully ...detected and tracked in on-field video sequences.•A new public dataset for grape cluster detection and segmentation is introduced.
Agricultural applications such as yield prediction, precision agriculture and automated harvesting need systems able to infer the crop state from low-cost sensing devices. Proximal sensing using affordable cameras combined with computer vision has seen a promising alternative, strengthened after the advent of convolutional neural networks (CNNs) as an alternative for challenging pattern recognition problems in natural images. Considering fruit growing monitoring and automation, a fundamental problem is the detection, segmentation and counting of individual fruits in orchards. Here we show that for wine grapes, a crop presenting large variability in shape, color, size and compactness, grape clusters can be successfully detected, segmented and tracked using state-of-the-art CNNs. In a test set containing 408 grape clusters from images taken on a trellis-system based vineyard, we have reached an F1-score up to 0.91 for instance segmentation, a fine separation of each cluster from other structures in the image that allows a more accurate assessment of fruit size and shape. We have also shown as clusters can be identified and tracked along video sequences recording orchard rows. We also present a public dataset containing grape clusters properly annotated in 300 images and a novel annotation methodology for segmentation of complex objects in natural images. The presented pipeline for annotation, training, evaluation and tracking of agricultural patterns in images can be replicated for different crops and production systems. It can be employed in the development of sensing components for several agricultural and environmental applications.
Collectively, reservoirs created by dams are thought to be an important source of greenhouse gases (GHGs) to the atmosphere. So far, efforts to quantify, model, and manage these emissions have been ...limited by data availability and inconsistencies in methodological approach. Here, we synthesize reservoir CH4, CO2, and N2O emission data with three main objectives: (1) to generate a global estimate of GHG emissions from reservoirs, (2) to identify the best predictors of these emissions, and (3) to consider the effect of methodology on emission estimates. We estimate that GHG emissions from reservoir water surfaces account for 0.8 (0.5–1.2) Pg CO2 equivalents per year, with the majority of this forcing due to CH4. We then discuss the potential for several alternative pathways such as dam degassing and downstream emissions to contribute significantly to overall emissions. Although prior studies have linked reservoir GHG emissions to reservoir age and latitude, we find that factors related to reservoir productivity are better predictors of emission.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The number of biological therapeutic agents in the clinic and development pipeline has increased dramatically over the last decade and the number will undoubtedly continue to increase in the coming ...years. Despite this fact, there are considerable challenges in the development, production and formulation of such biologics particularly with respect to their physical stabilities. There are many cases where self-association to form either amorphous aggregates or highly structured fibrillar species limits their use. Here, we review the numerous factors that influence the physical stability of peptides including both intrinsic and external factors, wherever possible illustrating these with examples that are of therapeutic interest. The effects of sequence, concentration, pH, net charge, excipients, chemical degradation and modification, surfaces and interfaces, and impurities are all discussed. In addition, the effects of physical parameters such as pressure, temperature, agitation and lyophilization are described. We provide an overview of the structures of aggregates formed, as well as our current knowledge of the mechanisms for their formation.
Lactococcus lactis
subsp.
cremoris
MG1363 is a paradigm strain for lactococci used in industrial dairy fermentations. However, despite of its importance for process development, no genome-scale ...metabolic model has been reported thus far. Moreover, current models for other lactococci only focus on growth and sugar degradation. A metabolic model that includes nitrogen metabolism and flavor-forming pathways is instrumental for the understanding and designing new industrial applications of these lactic acid bacteria. A genome-scale, constraint-based model of the metabolism and transport in
L
.
lactis
MG1363, accounting for 518 genes, 754 reactions, and 650 metabolites, was developed and experimentally validated. Fifty-nine reactions are directly or indirectly involved in flavor formation. Flux Balance Analysis and Flux Variability Analysis were used to investigate flux distributions within the whole metabolic network. Anaerobic carbon-limited continuous cultures were used for estimating the energetic parameters. A thorough model-driven analysis showing a highly flexible nitrogen metabolism, e.g., branched-chain amino acid catabolism which coupled with the redox balance, is pivotal for the prediction of the formation of different flavor compounds. Furthermore, the model predicted the formation of volatile sulfur compounds as a result of the fermentation. These products were subsequently identified in the experimental fermentations carried out. Thus, the genome-scale metabolic model couples the carbon and nitrogen metabolism in
L
.
lactis
MG1363 with complete known catabolic pathways leading to flavor formation. The model provided valuable insights into the metabolic networks underlying flavor formation and has the potential to contribute to new developments in dairy industries and cheese-flavor research.
Celotno besedilo
Dostopno za:
CEKLJ, DOBA, EMUNI, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK
Drosophila suzukii (Matsumura) is a species native to Western Asia that is able to pierce intact fruit during egg laying, causing it to be considered a fruit crop pest in many countries. Drosophila ...suzukii have a rapid expansion worldwide; occurrences were recorded in North America and Europe in 2008, and South America in 2013. Due to this rapid expansion, we modeled the potential distribution of this species using the Maximum Entropy Modeling (MaxEnt) algorithm and the Genetic Algorithm for Ruleset Production (GARP) using 407 sites with known occurrences worldwide and 11 predictor variables. After 1000 replicates, the value of the average area under the curve (AUC) of the model predictions with 1000 replicates was 0.97 for MaxEnt and 0.87 for GARP, indicating that both models had optimal performances. The environmental variables that most influenced the prediction of the MaxEnt model were the annual mean temperature, the maximum temperature of the warmest month, the mean temperature of the coldest quarter and the annual precipitation. The models indicated high environmental suitability, mainly in temperate and subtropical areas in the continents of Asia, Europe and North and South America, where the species has already been recorded. The potential for further invasions of the African and Australian continents is predicted due to the environmental suitability of these areas for this species.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In D=2+1 dimensions, elementary particles of a given helicity can be described by local Lagrangians (parity singlets). By means of a “soldering” procedure, two opposite helicities can be joined ...together and give rise to massive spin-s particles carrying both helicities ±s (parity doublets), and such Lagrangians can also be used in D=3+1 to describe massive spin-s particles. From this point of view the parity singlets (self-dual models) in D=2+1 are the building blocks of real massive elementary particles in D=3+1. In the three cases s=1, 3/2, 2 there are 2s self-dual models of order 1,2,…,2s in derivatives. In the spin-3 case the fifth order model is missing in the literature. Here we deduce a fifth order spin-3 self-dual model and fill up this gap. It is shown to be ghost free by means of a master action which relates it with the top model of sixth order. We believe that our approach can be generalized to arbitrary integer spin-s in order to obtain the models of order 2s and 2s−1. We also comment on the difficulties in relating the fifth order model with their lower order duals.
Zika virus (ZIKV) is an emergent threat provoking a worldwide explosive outbreak. Since January 2015, 41 countries reported autochthonous cases. In Brazil, an increase in Guillain-Barré syndrome and ...microcephaly cases was linked to ZIKV infections. A recent report describing low experimental transmission efficiency of its main putative vector, Ae. aegypti, in conjunction with apparent sexual transmission notifications, prompted the investigation of other potential sources of viral dissemination. Urine and saliva have been previously established as useful tools in ZIKV diagnosis. Here, we described the presence and isolation of infectious ZIKV particles from saliva and urine of acute phase patients in the Rio de Janeiro state, Brazil.
Nine urine and five saliva samples from nine patients from Rio de Janeiro presenting rash and other typical Zika acute phase symptoms were inoculated in Vero cell culture and submitted to specific ZIKV RNA detection and quantification through, respectively, NAT-Zika, RT-PCR and RT-qPCR. Two ZIKV isolates were achieved, one from urine and one from saliva specimens. ZIKV nucleic acid was identified by all methods in four patients. Whenever both urine and saliva samples were available from the same patient, urine viral loads were higher, corroborating the general sense that it is a better source for ZIKV molecular diagnostic. In spite of this, from the two isolated strains, each from one patient, only one derived from urine, suggesting that other factors, like the acidic nature of this fluid, might interfere with virion infectivity. The complete genome of both ZIKV isolates was obtained. Phylogenetic analysis revealed similarity with strains previously isolated during the South America outbreak.
The detection of infectious ZIKV particles in urine and saliva of patients during the acute phase may represent a critical factor in the spread of virus. The epidemiological relevance of this finding, regarding the contribution of alternative non-vectorial ZIKV transmission routes, needs further investigation.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background and Purpose
Ayahuasca (AYA) is a botanical psychedelic with promising results in observational and small clinical trials for depression, trauma and drug use disorders. Its psychoactive ...effects primarily stem from N,N‐dimethyltryptamine (DMT). However, there is a lack of research on how and where AYA acts in the brain. This study addressed these questions by examining the extinction of aversive memories in AYA‐treated rats.
Experimental Approach
We focused on the 5‐HT1A and 5‐HT2A receptors, as DMT exhibits a high affinity for both of them, along with the infralimbic cortex in which activity and plasticity play crucial roles in regulating the mnemonic process under analysis.
Key Results
A single oral treatment with AYA containing 0.3 mg·kg−1 of DMT increased the within‐session extinction of contextual freezing behaviour without affecting its recall. This protocol, when repeated twice on consecutive days, enhanced extinction recall. These effects were consistent for both 1‐ and 21‐day‐old memories in males and females. AYA effects on fear extinction were independent of changes in anxiety and general exploratory activity: AYA‐ and vehicle‐treated animals showed no differences when tested in the elevated plus‐maze. The 5‐HT2A receptor antagonist MDL‐11,939 and the 5‐HT1A receptor antagonist WAY‐100635 infused into the infralimbic cortex respectively blocked within‐ and between‐session fear extinction effects resulting from repeated oral administration of AYA.
Conclusion and Implications
Our findings highlight complementary mechanisms by which AYA facilitates the behavioural suppression of aversive memories in the rat infralimbic cortex. These results suggest potential beneficial effects of AYA or DMT in stress‐related disorders.
We suggest a new spin-4 self-dual model (parity singlet) and a new spin-4 parity doublet in D = 2 + 1. They are of higher order in derivatives and are described by a totally symmetric rank-4 tensor ...without extra auxiliary fields. Despite the higher derivatives they are ghost free. We find gauge invariant field combinations which allow us to show that the canonical structure of the spin-4 (spin-3) models follows the same pattern of its spin-2 (spin-1) counterpart after field redefinitions. For s = 1, 2, 3, 4, the spin- s self-dual models of order 2s−1 and the doublet models of order 2s can be written in terms of three gauge invariants. The cases s = 3 and s = 4 suggest a restricted conformal higher spin symmetry as a principle for defining linearized topologically massive gravity and linearized "new massive gravity" for arbitrary integer spins. A key role in our approach is played by the fact that the Cotton tensor in D = 2 + 1 has only two independent components for any integer spin.
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