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2021 ◽  
Vol 8 ◽  
Author(s):  
Waltraud C. Schrottmaier ◽  
Anita Pirabe ◽  
David Pereyra ◽  
Stefan Heber ◽  
Hubert Hackl ◽  
...  

Thromboembolic complications are frequently observed in Coronavirus disease 2019 (COVID-19). While COVID-19 is linked to platelet dysregulation, the association between disease outcome and platelet function is less clear. We prospectively monitored platelet activation and reactivity in 97 patients during the first week of hospitalization and determined plasma markers of platelet degranulation and inflammation. Adverse outcome in COVID-19 was associated with increased basal platelet activation and diminished platelet responses, which aggravated over time. Especially GPIIb/IIIa responses were abrogated, pointing toward impeded platelet aggregation. Moreover, platelet-leukocyte aggregate formation was diminished, pointing toward abrogated platelet-mediated immune responses in COVID-19. No general increase in plasma levels of platelet-derived granule components could be detected, arguing against platelet exhaustion. However, studies on platelets from healthy donors showed that plasma components in COVID-19 patients with unfavorable outcome were at least partly responsible for diminished platelet responses.Taken together this study shows that unfavorable outcome in COVID-19 is associated with a hypo-responsive platelet phenotype that aggravates with disease progression and may impact platelet-mediated immunoregulation.


2021 ◽  
Vol 82 (3) ◽  
pp. 76-78
Author(s):  
Tzvetomila Vladinova ◽  
Milena Georgieva

The P-T evolution of carbonate-bearing metasedimentary rocks from the Sakar unit (Sakar-Strandzha Zone, SE Bulgaria) has been obtained using Perple_X modelling and conventional geothermometry. The metamorphic conditions vary from greenschist facies (250–350 °C/2–4 kbar) in the Klokotnitsa village area to amphibolite facies (550–650 °C/4.5–6.5 kbar) in the Topolovgrad town area, confirming a general increase of the metamorphic grade at east-west direction.


2021 ◽  
Vol 124 (4) ◽  
pp. 977-994
Author(s):  
E. Norström ◽  
M.E. Kylander ◽  
S.R. Sitoe ◽  
J.M. Finch

Abstract This paper aims to identify chronostratigraphic palaeo-climatic boundaries based on proxy indications from mountain- and coastal wetlands in eastern South Africa and Lesotho. Phase boundaries were identified from timing of climate change inferred by proxies, as well as regime shifts in climate variability. Sometimes magnitude and/or frequency of change was also considered. Summarizing the common palaeo-climatic indications suggest the following chronostratigraphic climate phases: 25 to 18 ka, 18 to 15 ka, 15 to 11.5, 11.5 to 8 ka, 8 to 5.5 ka, 5.5 to 2 ka and 2 to 0 ka. The most robust boundaries were identified at 18 ka, 15 ka and 2 ka, i.e. these boundaries were supported by several proxies/sites. The other boundaries were less clearly detected from available proxies/sites and should be regarded tentative. The timing of a climate shift often coincides at coast and mountain sites. However, the climate conditions within each chronostratigraphic phase sometimes vary between coast and inland sites. The 25 to 18 ka phase was cool and dry with strong and frequent storms, followed by the ca. 18 to 15 ka period when conditions were less severe but still generally cool and dry. At ca. 15 to 11.5 ka several proxies infer warmer climate, with less winter rains. During 11.5 to 8 ka a general increase in wetness is inferred, followed by warming over the 8 to 5.5 ka phase. Between 5.5 and 2 ka a successive change towards wetter is indicated, although timing differ between sites. After 2 ka generally a more variable climate is seen, often with high magnitude shifts between dry and wet. The data resolution, i.e. the number of available wetland records, increases with time from very low during glacial times, to highest resolution during late Holocene. Geographically, sites in the mountain region are overrepresented compared to coastal sites. A comparison with coastal lake records suggests a more variable climate at coastal sites compared to mountain sites during mid- and late Holocene, although different proxy resolution and methodology cannot be ruled out as an explanation. A case study compares multiproxy records from Drakensberg (Sekhokong, Ntsikeni) and the coast (Mfabeni), discussing advantages and problems associated with proxy-comparisons within and between sites.


2021 ◽  
Vol 20 (1) ◽  
pp. 57-71
Author(s):  
Fred Wanda Masifwa ◽  
Peter Beine ◽  
James Ogwang ◽  
Moureen Matuha ◽  
Brenda Amondito ◽  
...  

The objective of this study was to quantify the coverage of Kariba weed (Salvinia molesta) on lakes Kyoga and Kwania and document the environmental and socio-economic impacts associated with its infestation. Data on weed infestation status was collected in 2017 and compared with pre-infestation period of 2013. Weed infestations were approximately 15,643 and 13,688 ha on lakes Kyoga and Kwania respectively. The infestation impaired fishing activities, water quality, water abstraction and water transport. They also led to 20.4, 60.1, 7.7, 17.6 and 5.7 kg reduction in catches per day for Tilapia, Mukene, Catfish, Nile perch and Mudfish respectively. The infestations were also associated with a general increase in the prices of the fish. Individual fishermen registered losses in fish revenue. Household spent approximately UGX 108,523 annually as treatment costs for diseases associated with weed infestation. While 32% of the respondents tried to manually control the waterweed at approximately UGX 83,988/year, the mobile nature of the weed rendered these efforts unsuccessful. A strategy to sustainably control the waterweed using specific bio-control agents (Cyrtobagous salviniae) is recommended.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Juan Luis Lechuga-Crespo ◽  
Sabine Sauvage ◽  
Estilita Ruiz-Romera ◽  
Michelle T. H. van Vliet ◽  
Jean-Luc Probst ◽  
...  

AbstractThis study simulates carbon dioxide (CO2) sequestration in 300 major world river basins (about 70% of global surface area) through carbonates dissolution and silicate hydrolysis. For each river basin, the daily timescale impacts under the RCP 2.6 and RCP 8.5 climate scenarios were assessed relative to a historical baseline (1969–1999) using a cascade of models accounting for the hydrological evolution under climate change scenarios. Here we show that the global temporal evolution of the CO2 uptake presents a general increase in the annual amount of CO2 consumed from 0.247 ± 0.045 Pg C year−1 to 0.261 and 0.273 ± 0.054 Pg C year−1, respectively for RCP 2.6 and RCP 8.5. Despite showing a general increase in the global daily carbon sequestration, both climate scenarios show a decrease between June and August. Such projected changes have been mapped and evaluated against changes in hydrology, identifying hot spots and moments for the annual and seasonal periods.


Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7154
Author(s):  
Fauzi Handoko ◽  
Yusril Yusuf

The purpose of this study was to utilize cellulose from tea waste as nanocrystalline cellulose (NCC), which is used as a filler in poly(vinyl) alcohol (PVA) nanocomposites. To obtain the NCC, a chemical process was conducted in the form of alkali treatment, followed by bleaching and hydrolysis. Nanocomposites were formed by mixing PVA with various NCC suspensions. With chemical treatment, lignin and hemicellulose can be removed from the tea waste to obtain NCC. This can be seen in the functional groups of cellulose and the increase in crystallinity. The NCC had a mean diameter of 6.99 ± 0.50 nm. Furthermore, the addition of NCC to the PVA nanocomposite influenced the properties of the nanocomposites. This can be seen in the general increase in opacity value, thermal and mechanical properties, and crystallinity, as well as the decrease in the value of the swelling ratio after adding NCC. This study has revealed that NCC from tea waste can be used to improve the physicochemical properties of PVA film.


Significance The closing of internal and external borders in response to COVID-19 has heightened a longstanding skills deficit in key industries, with implications for wage levels, prices and broader economic growth. However, a general increase in immigrant numbers may not provide the skills that are needed. Impacts Labour shortfalls may delay government infrastructure projects that were designed to lead the post-pandemic economic recovery. Foreign investment may be affected by skills shortages in key areas such as mining and metallurgy. Debate on immigration levels could influence voting in the general election that is now likely to be held in April.


Water ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3171
Author(s):  
Micah Lourdes Felix ◽  
Young-kyu Kim ◽  
Mikyoung Choi ◽  
Joo-Cheol Kim ◽  
Xuan Khanh Do ◽  
...  

To investigate the recent effects of climate change in the upper Geum River basin in South Korea, a detailed trend analysis of 17 extreme climate indices based on 33 years (1988–2020) of daily precipitation, and daily (minimum and maximum) temperature data has been analyzed in this study. Out of the 17 extreme climate indices, nine (eight) indices were based on temperature (precipitation) data. Trend analysis based on detailed temporal scales (annual, seasonal, monthly) were performed through the Mann–Kendall trend test and the Theil–Sen slope method. Furthermore, the Mann–Whitney–Pettit test was also applied in this study, to detect abrupt changes in the extreme climate indices. Based on the results of this study, the climate conditions at the upper Geum River basin for the past three decades can be summarized as follows: general increase in temperature intensity, decrease in cold duration, increased heat duration, increased precipitation intensity, and increased consecutive wet and dry durations. Furthermore, a prolonged summer season (shorter spring, and autumn periods) and precipitation shifts, were detected based on trend analysis results of seasonal, and monthly time scales. The results presented in this study can provide supplementary data for improving watershed management strategies in the upper Geum River basin.


2021 ◽  
Vol 107 (3) ◽  
pp. 213-228
Author(s):  
Gina E. Morimoto ◽  
Anae B. Otto ◽  
Laura L. Burkholder

Concrete-lined water conveyance canals can be a significant source of mortality for ungulates and other wildlife, which can drown or become entrapped. Various types of wildlife escape structures have been deployed in canals with limited success. From 2011 to 2018, we used camera traps to monitor mule deer (Odocoileus hemionus) use of three different temporary wildlife escape structure designs with the goal of developing an effective escape structure for fawns. We monitored three to five locations at a hydroelectric water conveyance canal, operated by Pacific Gas and Electric Company in the foothills of Central California on the Sierra National Forest, in which trapped fawns had been detected previously during the maintenance period when the canal was dry. Mule deer activity and ramp use varied by year. During the monitoring period, deer were detected in the canal in all years except 2016 and 2017. Fawns and adults used the temporary escape structures to exit the canal in four of these years and 50% of mule deer detections showed ramp use overall. No deer were detected using the escape structures until jute netting and debris were added to the surface of the escape ramps in the third monitoring year. Prior to this modification, fawns were detected trapped in the canal investigating the ramps, but not using them to exit the canal. Deer may be more likely to utilize ramps covered with materials that mimic native ground cover. Seven other wildlife species were detected entering and exiting using the ramps with a general increase in use over years. Our temporary escape ramp design for small canals, when dry, appears to be novel and may be applicable in other areas. When compared to fencing or covering the canal, it is a relatively low-cost solution to reduce animal entrapment.


Author(s):  
Т.Л. Визило ◽  
Т.В. Попонникова ◽  
И.Ф. Федосеева ◽  
Е.Д. Васенина

На современном этапе в России наблюдается тенденция к увеличению регистрации случаев нейросифилиса на фоне снижения заболеваемости сифилитической инфекцией в целом. Рост заболеваемости нейросифилисом отражает ситуацию с повышением частоты первичных форм сифилиса в конце 90-х – начале 2000-х годов, когда в нашей стране разразилась эпидемия этого заболевания. По мнению большинства специалистов, бледная трепонема всегда попадает в нервную систему, причем в одних случаях ее присутствие является транзиторным, а в других наблюдается асимптомное персистирование, в третьих манифестирует нейросифилис. В настоящее время лечение сифилиса проводится чаще всего амбулаторно дюрантными формами (бензатинбензилпенициллины), которые создают длительную (в течение нескольких суток и вплоть до 18‑21 дня после однократного введения), но низкую концентрацию пенициллина в организме. Препараты плохо преодолевают гематоэнцефалический барьер, следовательно, при недиагностированном скрытом сифилитическом менингите не достигается санация ликвора и сохраняется возможность развития поздних манифестных форм нейросифилиса. Авторы описывают трудности диагностики нейросифилиса и приводят клинический случай ишемического инсульта у молодого больного с нейросифилисом. Лабораторные данные подтвердили наличие сифилиса, а ликворологическое обследование и клинические данные позволили установить диагноз менинговаскулярного сифилиса. Авторы отмечают, что особого внимания требует соблюдение алгоритма клинико-лабораторного обследования пациентов при наличии у них нарушений функции центральной и периферической нервной системы, органов зрения и слуха независимо от давности предполагаемого заражения и предполагаемой серорезистентности. Поскольку нейросифилис является междисциплинарной проблемой, необходимо комплексное клинико-лабораторное и клинико-инструментальное обследование пациентов с участием врачей разного профиля. At the modern stage in Russia, we can observe the tendency of increase in recording cases of neurosyphilis against the background of reduction of morbidity rate of syphilitic infection in general. Increase of neurosyphilis morbidity reflects the situation of frequency increase of primary forms of syphilis in the end of the 90s – beginning of the 2000s, when our country faced with epidemic of this disease. Most experts assume that treponema pallidum always penetrates in the nervous system, in some cases its presence being transitory, in other cases, we observe asymptomatic persistence, and in some, neurosyphilis manifests. Currently, most often syphilis therapy takes place on outpatient basis with repository forms ((Benzathine benzylpenicillins) which create long (during several days and up to 18-21 days after one-time administration), but low concentration of penicillin in the body. These drugs badly overcome blood-brain barrier, consequently, if syphilitic meningitis is latent and not diagnosed, liquor sanation is not achieved, and potential development of neurosyphilis manifest forms is retained. The authors describe the difficulties of diagnosis of neurosyphilis and a clinical case of ischemic stroke in a young patient with neurosyphilis. Diagnosis of syphilis was confirmed by laboratory studies; liquor tests and clinical data allowed to diagnose meningovascular syphilis. The authors highlight that special attention should be paid to observance of algorithm of clinical-laboratory examination of patients if they have disorders in functions of central and peripheral nervous systems, organs of vision and hearing, regardless of remoteness of supposed infection and supposed seroresistance. As neurosyphilis is interdisciplinary problem, complex clinical-laboratory and clinical-instrumental examination of patients is required, involving medical specialists of different profiles.


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