Abstract
Risk management has reduced vulnerability to floods and droughts globally
1,2
, yet their impacts are still increasing
3
. An improved understanding of the causes of changing impacts is ...therefore needed, but has been hampered by a lack of empirical data
4,5
. On the basis of a global dataset of 45 pairs of events that occurred within the same area, we show that risk management generally reduces the impacts of floods and droughts but faces difficulties in reducing the impacts of unprecedented events of a magnitude not previously experienced. If the second event was much more hazardous than the first, its impact was almost always higher. This is because management was not designed to deal with such extreme events: for example, they exceeded the design levels of levees and reservoirs. In two success stories, the impact of the second, more hazardous, event was lower, as a result of improved risk management governance and high investment in integrated management. The observed difficulty of managing unprecedented events is alarming, given that more extreme hydrological events are projected owing to climate change
3
.
Micro Air Vehicles (MAVs) have the potential to revolutionize our capabilities in gathering information, monitoring situations, and surveillance. They are required to maneuver in and around obstacles ...as well as negotiate atmospheric disturbances whilst holding accurate trajectories and minimizing rotation which can blur imagery. A study of existing literature on MAV control challenges found that current turbulence mitigation systems and control surface configurations lack the speed of response and control authority required to maintain steady flight in turbulence. Improved control response may come from unconventional designs, bio-inspired systems, or from careful manipulation of the flow mechanics. As such, in this paper, key unsteady aerodynamic parameters are also reviewed and considered prior to deriving potential control solutions that could help MAVs fly well in turbulence.
OCTOPUS database (v.2) Codilean, Alexandru T; Munack, Henry; Saktura, Wanchese M ...
Earth system science data,
08/2022, Letnik:
14, Številka:
8
Journal Article
Recenzirano
Odprti dostop
OCTOPUS v.2 is an Open Geospatial Consortium (OGC) compliant web-enabled database that allows users to visualise, query, and download cosmogenic radionuclide, luminescence, and radiocarbon ages and ...denudation rates associated with erosional landscapes, Quaternary depositional landforms, and archaeological records, along with ancillary geospatial (vector and raster) data layers. The database follows the FAIR (Findability, Accessibility, Interoperability, and Reuse) data principles and is based on open-source software deployed on the Google Cloud Platform. Data stored in the database can be accessed via a custom-built web interface and via desktop geographic information system (GIS) applications that support OGC data access protocols. OCTOPUS v.2 hosts five major data collections. CRN Denudation and ExpAge consist of published cosmogenic 10Be and 26Al measurements in modern fluvial sediment and glacial samples respectively. Both collections have a global extent; however, in addition to geospatial vector layers, CRN Denudation also incorporates raster layers, including a digital elevation model, gradient raster, flow direction and flow accumulation rasters, atmospheric pressure raster, and CRN production scaling and topographic shielding factor rasters. SahulSed consists of published optically stimulated luminescence (OSL) and thermoluminescence (TL) ages for fluvial, aeolian, and lacustrine sedimentary records across the Australian mainland and Tasmania. SahulArch consists of published OSL, TL, and radiocarbon ages for archaeological records, and FosSahul consists of published late-Quaternary records of direct and indirect non-human vertebrate (mega)fauna fossil ages that have been systematically quality rated. Supporting data are comprehensive and include bibliographic, contextual, and sample-preparation- and measurement-related information. In the case of cosmogenic radionuclide data, OCTOPUS also includes all necessary information and input files for the recalculation of denudation rates using the open-source program CAIRN. OCTOPUS v.2 and its associated data curation framework allow for valuable legacy data to be harnessed that would otherwise be lost to the research community. The database can be accessed at https://octopusdata.org (last access: 1 July 2022). The individual data collections can also be accessed via their respective digital object
identifiers (DOIs) (see Table 1).
Cryobanks are a secure, efficient and low cost method for the long-term conservation of plant genetic resources for theoretically centuries or millennia with minimal maintenance.
The present ...manuscript describes CIP's modified protocol for potato cryopreservation, its large-scale application, and the establishment of quality and operational standards, which included a viability reassessment of material entering the cryobank.
In 2013, CIP established stricter quality and operational standards under which 1,028 potato accessions were cryopreserved with an improved PVS2-droplet protocol. In 2014 the viability of 114 accessions cryopreserved in 2013 accessions were reassessed.
The average recovery rate (full plant recovery after LN exposure) of 1028 cryopreserved Solanum species ranged from 34 to 59%, and 70% of the processed accessions showed a minimum recovery rate of ≥20% and were considered as successfully cryopreserved.
CIP has established a new high quality management system for cryobanking. Periodic viability reassessment, strict and clear recovery criteria and the monitoring of the percent of successful accessions meeting the criteria as well as contamination rates are metrics that need to be considered in cryobanks.
Dust emission fluxes during wind soil erosion are usually estimated using a dust concentration vertical gradient, by assuming a constant dust flux layer between the surface and the dust measurement ...levels. Here, we investigate the existence of this layer during erosion events recorded in Iceland and Jordan. Size‐resolved dust fluxes were estimated at three levels between 2 and 4 m using the eddy‐covariance method. Dust fluxes were found mainly constant only between the two upper levels in Iceland, the lower dust flux being often stronger and richer in coarse particles, while dust fluxes in Jordan were nearly constant across all levels. The wind dynamics could not explain the absence of a constant dust flux layer in Iceland. We show that the presence of stationary dust source patches in Iceland, related to surface humidity, created a non‐uniform dust layer near the surface, named dust roughness sublayer (DRSL), where individual plumes behind each patch interact but do not fully mix. The lowest dust measurement level was probably located within this sublayer while the upper ones were located above, such that there the emitted dust became spatially well‐mixed. This explains near the surface in Iceland, the more intermittent dust concentration, its low correlation with the dust concentrations above, and the richer dust flux in coarse particles due to their lower deposition contribution. Our findings highlight the importance of estimating dust fluxes above a dust blending height whose characteristics depend on the dust source patchiness caused by surface humidity or the presence of sparse non‐erosive elements.
Plain Language Summary
During soil erosion by wind, dust flux from the surface is estimated at a few meters height, by assuming the existence of a constant dust flux layer between the surface and the dust measurement levels. Here, we investigated for the first time the existence of this layer during erosion events in Iceland and Jordan, by estimating the dust fluxes at three levels between 2 and 4 m height. In Iceland, the dust fluxes were constant only between the two upper levels. In Jordan, the dust fluxes remained constant across all levels. We demonstrates that the absence of a constant dust flux layer in Iceland is due to patches of stationary dust sources, which are related to surface humidity. These patches created a non‐uniform dust layer near the surface, known as the dust roughness sublayer. In this layer, individual plumes behind each patch interact but do not fully mix. The lowest dust measurement level was likely within this sublayer, while the upper measurements were located above it. Our findings highlight the importance of estimating dust fluxes above a dust blending height, which depends on the patchiness of the dust source caused by surface humidity or the presence of sparse non‐erosive elements.
Key Points
Size‐resolved dust emission fluxes have been estimated for the first time at different heights during erosion events in Iceland and Jordan
Unlike in Jordan, the absence of a constant dust flux layer in Iceland is due to the dust source patchiness related to surface humidity
Our results highlight the importance of estimating dust fluxes above a dust blending height that depends on the dust source patchiness
The effect of shoot tip pre-culture on media with varying sucrose levels (0.0-0.6 M) followed by treatment with Plant Vitrification Solution 2 PVS2 (15, 30, 45, 60 min) was evaluated with six sweet ...potato accessions Ipomoea batatas (L.) Lam., using the "PVS2-droplet vitrification" cryopreservation method. No significant differences in the percent of shoot regeneration were observed when shoot tips were pre-cultured on sucrose concentrations ranging from 0.1 to 0.4 M. The highest mean shoot regeneration rate of 57.7 ± 5.5% after rewarming from cryopreservation (+LN) was obtained with a sucrose concentration of 0.35 M. Intermediate exposure times in PVS2 of 30 and 45 min showed statistically better results than shorter or longer exposure, with a maximum mean shoot regeneration (+LN) of 68.5 ± 4.5% with a 30 min exposure. Screening a separate larger group of 24 sweet potato accessions with a 0.35 M sucrose pre-culture and 30 min PVS2 treatment (+LN) resulted in shoot formation rates ranging from 1.7 to 66%.
Bone marrow examination in cases of pancytopenia Jha, A; Sayami, G; Adhikari, R C ...
Journal of Nepal Medical Association,
2008 Jan-Mar, 2008-01-01, 20080101, Letnik:
47, Številka:
169
Journal Article
Recenzirano
Odprti dostop
This study was carried to identify the causes of pancytopenia and to find out the bone marrow morphology in cases of pancytopenia. It was a cross sectional study conducted over a period of two years ...in the Department of Pathology, Tribhuvan University Teaching Hospital. Bone marrow aspiration smears of patients fulfilling the criteria of pancytopenia were examined. The data obtained were analyzed using measures of central tendency. One hundred and forty eight cases underwent bone marrow aspiration and it constituted 15.74% of total cases. Mean age was 30 years (range, 1-79 years). 42 cases were children (28.37%). Male: female ratio was 1.5:1. The commonest cause was hypoplastic bone marrow seen in 43 cases (29%) followed by megaloblastic anemia in 35 cases (23.64%), and hematological malignancy in 32 cases (21.62%). Erythroid hyperplasia was seen in 29 cases (19.6%) and normal bone marrow was seen in 5 cases (3.38%). There was one case each of Niemann-Pick disease and metastatic neuroblastoma in children and chronic pure red cell aplasia and leishmaniasis in adults. Acute leukemia was the commonest hematological malignancy. In children, commonest finding was hypoplastic bone marrow (38.1%) while in adults megaloblastic anemia (30.18%) was commonest finding followed by hypoplastic anemia (25.47%). In present study bone marrow examination was able to establish diagnosis in 77% of cases. Hypoplastic marrow was the commonest diagnosis, followed by megaloblastic anemia, and hematological malignancies.
Using the PVS2 droplet vitrification cryopreservation technique for long-term potato conservation, it was found that some surviving shoot tips turned brown followed by necrosis during the recovery ...stage, suggesting that oxidation processes are involved in the viability decline. With this hypothesis, we investigated the effect of two antioxidants, ascorbic acid and glutathione, on tissue survival and plantlet recovery. Apical shoot tips from 3-week-old in vitro plantlets of S. tuberosum subsp. andigenum ‘Ccompis’ and ‘Tacna’, a multiple hybrid from cultivated and wild species, were subjected to the cryopreservation protocol using the PVS2 droplet vitrification method. One experiment was executed using three doses of ascorbic acid (50, 100 and 150 mg/L) and another with glutathione (5, 10, 15 mg/L), added to the post-thaw medium. Ascorbic acid showed a significant negative effect on the survival and recovery of shoot tips of both cultivars, without any genotype differences. In case of glutathione, ‘Ccompis’ plantlets showed superior survival and recovery rates compared to ‘Tacna’ plantlets, but the differences were not statistically significant.
The stability of the atmosphere plays a major role in the dispersion of pollutants. The meteorological conditions favoring a high-pressure situation resulting in the formation of inversion layer ...inhibits pollutant dispersion. The aim of the study was to obtain vertical profiles of meteorological parameters and air pollutants in order to investigate the impact of inversion on the air quality of this city. Vertical profiles help to understand the behaviour of temperature inversion, pollutants and their relationship to each other. The tethered balloon was equipped with in-situ instruments to measure Particulate Matter (PM), Black Carbon (BC), Ultra Fine Particles (UFP) as well as meteorological parameters such as air temperature, relative humidity, wind speed and wind direction of the lower troposphere. The measurements were carried out in “Schlossgarten”, a park area near the city center of Stuttgart. Vertical profiles were obtained by ascending the balloon from ground up to a height of a maximum of 470 m and then descending it back to the ground. One complete sounding (ascent and descent) took around 30–40 min. The measurement campaign took place on 8th and July 9, 2018. 43 soundings were performed during that period. During the measurement campaign, a distinct inversion was observed at nighttime, which trapped the pollutants, hence increasing the pollutant concentration near the ground within the inversion layer. PM, UFP and BC concentrations showed a decreasing trend with increasing altitude but during noon, when the atmosphere was well mixed, the concentrations were relatively constant along with increasing altitude.
•Strong temperature inversions during the night.•Higher pollutant concentrations within the inversion layer.•Decrease in pollutant concentration with increasing altitude.•Lower wind speeds near the ground due to friction and obstruction.
Ulluco (Ullucus tuberosus Cal.) and oca (Oxalis tuberosa Mol.) are Andean tuber crops of significant importance for the nutrition and subsistence of the Andean people. The world’s largest germplasm ...collections of these crops, comprised of 544 and 628 accessions of ulluco and oca, respectively, are maintained at the International Potato Center (CIP). For their long-term conservation, CIP is currently developing cryopreservation techniques. Post-thaw survival and recovery resulting from shoot cryopreservation using plants cultured under different temperature regimes were investigated with 4 accessions each of ulluco and oca. Apical shoot tips from 3-week-old in vitro ulluco and oca plantlets were cryopreserved using the droplet-vitrification protocol. Shoot tips of 2 mm size were exposed to a loading solution for 20 min, dehydrated with PVS2 for 0, 15, 30, 45, 60 and 75 min, at 0°C, transferred to aluminium foil strips and plunged into liquid nitrogen. The highest recovery after cryopreservation was 35 and 15% for ulluco and oca, respectively, using 60 min of exposure to PVS2. In a second assay, in vitro donor plants of ulluco and oca were cultured at a constant temperature of 6°C, or alternating temperatures of 18°C in week 1 and 6°C in week 2. Shoot tips were cryopreserved following the protocol described above with 60 min exposition of exposure to PVS2. A constant low temperature did not increase the recovery percentage after cryopreservation. It did increase, however, with 5% in ulluco and 4% in oca plantlets when alternating temperatures were applied. These results showed that cryopreservation could be applied for long-term conservation of ulluco and oca germplasm collections.
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