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Author(s):  
S. Yu. Babenkova

The Qatar National Vision 2030 program is based on two principles — modernization and preservation of traditions. Blockade of the country in 2017–2020 and the coronavirus pandemic became a serious test for the economy of Qatar, but the government and residents of the country do not consider themselves defeated by these circumstances, but on the contrary, these circumstances helped the country’s economy to survive the above crises. In 2019, the International Monetary Fund said that Qatar’s economy was resilient in the face of the blockade and shocks caused, including by the fall in hydrocarbon prices in 2014–2016. The events of the global economic crisis caused by the pandemic have posed another challenge to the financial and banking system of Qatar. Thanks to the measures of the country’s government aimed at ensuring business continuity, maintaining liquidity and providing support to the sectors of the economy affected by the pandemic, it was possible to mitigate the impact of this shock, support cash flows, and achieve financial and banking stability in the country. However, according to fund analysts, COVID–19 and a sharp drop in hydrocarbon revenues will lead to a reduction in real GDP growth by 2% in 2020. At the same time, future profits from hosting the FIFA World Cup in 2022, continued expansion of capacities in production of liquefied gas and competent fiscal and monetary policy will contribute to economic growth in the country in the medium term.


2022 ◽  
Vol 2152 (1) ◽  
pp. 012035
Author(s):  
Jiaqi Zuo

Abstract Currently, the magic-angle graphene has given a tremendous boost to the study of unconventional superconductors. On the other hand, there were still limited experimental studies on superconductivity in one-dimensional (1D) carbon nanotube systems. The study of experimental systems in demonstrating superconductivity was therefore scientifically important. In this review, we have shown strategies toward demonstrating the superconductivity for the single double-wall carbon nanotube (DWCNT). In general, there have been two directions to analyse superconducting properties of one-dimensional materials: (i) strong correlated states (ii) anomalous electron transport operations. We introduced the transmission electron microscope (TEM) and Rayleigh scattering spectroscopy to describe the strong correlation. The theoretical foundations of moiré physics have also been described. Given all the methods, we concluded that the most intuitive way to demonstrate the superconductivity of single double-walled carbon nanotubes is the critical temperature. The sharp drop of the resistance could be directly observed, and the Tc could be obtained from the electrical transport data. In the last section, we also summarized the challenges that need to be addressed in future superconductivity studies of 1D carbon nanotubes.


2022 ◽  
pp. 252-269
Author(s):  
Temitope Teniola Onileowo ◽  
Farrah Merlinda Muharam ◽  
Mohd Khairuddin Ramliy

This chapter addressed Coronavirus disease 2019 (COVID-19) impact on tertiary institutions in Nigeria, its effect on the economy, and possible coping strategies in a time of global pandemic and national disaster. COVID-19 was reported as a pandemic by the World Health Organization (WHO) on March 11, 2020, discovered in Wuhan, China, in December 2019, spread to several nations, forcing the closure of tertiary institutions all over the world. The effect has also disrupted the school academic calendar at tertiary institutions, decreased international education, Suspension of local and international conferences, etc. And the economy, leading to job losses, revenue loss in the informal sector, business closure, agricultural production and food insecurity, a sharp drop in oil revenues, and economic uncertainties. Which, thus, harms the economy. This chapter makes recommendations to assist Nigeria's government and the educational institutions in coping with the effect of the outbreak and similar pandemics soon.


2021 ◽  
Author(s):  
Nilce Maria Soares ◽  
Edna Clara Tucci ◽  
Gustavo Perdoncini ◽  
Ricardo Della Matta Junior

Abstract BackgroundMite infestations in laying hens can cause losses to producers due to stress, reduced egg production and even death of birds. A new species of mite, Allopsoroptoides galli (A. galli), Analgoidea: Psoroptoididae, was recently identified in commercial laying farms in Brazil, causing damage due to its highly aggressive infestation that results in a sharp drop in egg production and culling. The present study evaluated the acaricidal action of a formulation containing fluralaner (Exzolt®) against A. galli.Methods The study was carried out from November 2019 to January 2020. Thirty-four laying hens naturally infested with A. galli were equally divided into a fluralaner-treated group and an untreated control group. The fluralaner-treated group received Exzolt® in drinking water at a dose of 0.05 mL/kg body weight (equivalent to 0.5 mg fluralaner/kg body weight), twice, seven days apart. Both groups were followed for 70 days evaluating the level of infestation by counting mites in skin scrapings and assessment of skin lesions.Results The average mite count of the treated group decreased significantly, dropping from 61.6 to 3.8 mites (D+7 to D+70). The efficacy progressively increased on subsequent days, reaching 98.8% on day +56 post-treatment and 96.9% on day +70. Recovery of skin lesions was observed after administration of Exzolt®, showing a marked remission in the degree of lesions (2.5 on day -14 to 0.2 on day +70). The mean number of mites in the untreated control group ranged from 79.3 to 124.1 and the lesion score from 2.6 to 2.9, thus remaining stable throughout the study.Conclusion The results obtained in the present study demonstrated that Exzolt® administered at a dose of 0.05 mL of product/kg body weight (equivalent to 0.5 mg of fluralaner/kg body weight), twice at a seven-day interval, in drinking water was effective in the treatment of the mite Allopsoroptoides galli in naturally infested laying hens.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Na Hyun Jo ◽  
Yun Wu ◽  
Thaís V. Trevisan ◽  
Lin-Lin Wang ◽  
Kyungchan Lee ◽  
...  

AbstractElectrons navigate more easily in a background of ordered magnetic moments than around randomly oriented ones. This fundamental quantum mechanical principle is due to their Bloch wave nature and also underlies ballistic electronic motion in a perfect crystal. As a result, a paramagnetic metal that develops ferromagnetic order often experiences a sharp drop in the resistivity. Despite the universality of this phenomenon, a direct observation of the impact of ferromagnetic order on the electronic quasiparticles in a magnetic metal is still lacking. Here we demonstrate that quasiparticles experience a significant enhancement of their lifetime in the ferromagnetic state of the low-density magnetic semimetal EuCd2As2, but this occurs only in selected bands and specific energy ranges. This is a direct consequence of the magnetically induced band splitting and the multi-orbital nature of the material. Our detailed study allows to disentangle different electronic scattering mechanisms due to non-magnetic disorder and magnon exchange. Such high momentum and energy dependence quasiparticle lifetime enhancement can lead to spin selective transport and potential spintronic applications.


2021 ◽  
Vol 922 (2) ◽  
pp. 192
Author(s):  
Axel Brandenburg ◽  
Yutong He ◽  
Ramkishor Sharma

Abstract Using numerical simulations of helical inflationary magnetogenesis in a low reheating temperature scenario, we show that the magnetic energy spectrum is strongly peaked at a particular wavenumber that depends on the reheating temperature. Gravitational waves (GWs) are produced at frequencies between 3 nHz and 50 mHz for reheating temperatures between 150 MeV and 3 × 105 GeV, respectively. At and below the peak frequency, the stress spectrum is always found to be that of white noise. This implies a linear increase of GW energy per logarithmic wavenumber interval, instead of a cubic one. Both in the helical and nonhelical cases, the GW spectrum is followed by a sharp drop for frequencies above the respective peak frequency. In this magnetogenesis scenario, the presence of a helical term extends the peak of the GW spectrum and therefore also the position of the aforementioned drop toward larger frequencies compared to the case without helicity. This might make a difference in it being detectable with space interferometers. The efficiency of GW production is found to be almost the same as in the nonhelical case, and independent of the reheating temperature, provided the electromagnetic energy at the end of reheating is fixed to be a certain fraction of the radiation energy density. Also, contrary to the case without helicity, the electric energy is now less than the magnetic energy during reheating. The fractional circular polarization is found to be nearly 100% in a certain range below the peak frequency range.


2021 ◽  
Author(s):  
Robert Joseph Kosinski

This paper simulates an ideal COVID-19 vaccine that confers immediate sterilizing immunity against all SARS-CoV-2 variants. The purpose was to explore how well this ideal vaccine could protect a population against common conditions (such as vaccine hesitancy) that might impair vaccine effectiveness. Simulations were done with an SEIRS spreadsheet model that ran two parallel subpopulations: one that accepted vaccination, and another that refused it. The two subpopulations could transmit infections to one another. Success was judged by the rate of new cases in the period from 1-5 years after the introduction of the vaccine. Under good conditions, including a small subpopulation that refused vaccination, rapid distribution of the vaccine, duration of vaccinal immunity longer than 12 months, good retention of interest in getting vaccinated after the first year, strict maintenance of nonpharmaceutical interventions (NPIs) such as masking, and new variants with R0s less than 4.0, the vaccine was able to end the epidemic. With violation of these conditions, the post-vaccine era futures ranged from endemic COVID at a low or medium level to rates of COVID cases worse than anything seen in the US up to late 2021. The most important conditions for keeping case rates low were a fast speed of vaccine distribution, a low percentage of the population that refuses vaccination, a long duration of vaccinal immunity, and continuing maintenance of NPIs after vaccination began. On the other hand, a short duration of vaccinal immunity, abandonment of NPIs, and new variants with a high R0 were powerful barriers to disease control. New variants with high R0s were particularly damaging, producing high case rates except when vaccination speed was unrealistically rapid. A recurring finding was that most disease afflicting the vaccinated population in these simulations originated in the unvaccinated population, and cutting off interaction with the unvaccinated population caused a sharp drop in the case rate of the vaccinated population. In conclusion, multiple common conditions can compromise the effectiveness of even an ideal vaccine.


Forests ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1596
Author(s):  
Xiaobo Yang ◽  
Long Li ◽  
Xiaobo Lv ◽  
Wenqi Luo ◽  
Donghai Li ◽  
...  

The successful establishment of many plants in tropical forests often depends on species-specific adaptations related to light availability and forest successional stage. Species that are present in early successional stages generally do not occur in later successional stages. In this study, we documented the diversity, distribution, and abundance of terrestrial invasive plants across the (sub)tropical island of Hainan, China, and tested the germination of specific invasive plants in forested environments. In 97 transects positioned randomly across the island, we found nine invasive herb and shrub species were present in all human-modified habitats but not in intact forest interiors. In separate forest-specific transects, we documented a sharp drop in the abundance of invasive plants >5 m into the forest. High numbers of invasive plant seeds germinated from the soil seed bank sampled at the forest edge, but very few seeds germinated from soil sampled any distance into the forest. Finally, in experiments with four focal invasive plant species, overall germination rates were low; and much lower in shaded sites compared to full gap sites. In conclusion, our findings demonstrated that invasive herbs and shrubs do not yet form a serious threat to native species in the closed-canopy forests of Hainan.


2021 ◽  
Vol 2 (4) ◽  
pp. 18-25
Author(s):  
D. A. Rozenko ◽  
N. D. Ushakova ◽  
S. N. Tikhonova ◽  
Yu. N. Lazutin ◽  
N. N. Popova ◽  
...  

This clinical observation demonstrates a method of a motivated use of a transdermal therapeutic system (TTS) based on fentanyl for chemical pleurodesis in a patient with prolonged air leakage after lung resection for cancer. The most common complication after elective lung resections is an alveolar-pleural fistula or prolonged air leakage. This clinical phenomenon occurs as a result of communication between the alveoli of the lung parenchyma distal to the segmental bronchus and the pleural cavity. In most cases, air leakage through the drains is eliminated spontaneously, but the frequency of prolonged pneumostasis absence in the postoperative period can reach 25 %, which has a negative effect on the outcomes of surgical interventions due to the development of pneumonia and empyema. Long-term drainage of the pleural cavity does not always end with aerostasis and requires repeated invasive interventions. One of the ways to achieve the tightness of the lung tissue involves various methods of chemical pleurodesis, which is a surgical manipulation – the introduction of a sclerosing chemical substance into the pleural cavity by spraying medical talc through a trocar or a injecting tetracycline solution into the pleural drains. The chemical causes aseptic inflammation and adhesions between the visceral and parietal pleura, followed by obliteration of the pleural cavity. The sclerosant introduction is accompanied by severe pain that can provoke respiratory and/or hemodynamic deficits, up to apnea and life-threatening heart rhythm disturbances. Pain relief during chemical pleurodesis is obviously an important factor in the prevention of a number of complications in patients undergoing surgery for lung cancer. Bolus intravenous injections of narcotic analgesics lead to an analgesic effect, but a short-term one due to the absence of a depot in the body and a sharp drop in the drug concentration in the blood serum. Unfortunately, this method of introducing narcotic drugs can cause various complications in weakened and elderly cancer patients, such as respiratory depression and cardiac arrest. The TTS action is characterized with continuous dosing and the creation of a constant concentration of the narcotic drug over a certain period of time. This method provides a multilevel and systematic approach to pain relief, reduces toxicity and minimizes the inhibition of the central mechanisms of external respiration regulation without causing respiratory and cardiac disorders in patients who underwent lung resection.


Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 3698-3698
Author(s):  
Yael Haring ◽  
Nitzan Cohen Sagy ◽  
Shaimaa Taha ◽  
Albert Kolomansky ◽  
Howard S. Oster ◽  
...  

Abstract Background: Quality of life (QoL) is impaired in MDS. Aims: 1) To study QoL for various levels of anemia in MDS patients at diagnosis, 2) Compare with non-MDS controls. 3) Compare at MDS diagnosis to 1 year later. Methods: Patients in The Israel MDS registry fill out the EQ-5D QoL questionnaire. The evaluated parameters are: mobility, self-care, daily activities, pain/discomfort and anxiety/depression, each scored 0(normal), 1(mild/moderate), or 2(poor). They also evaluate their general health using a visual analogue scale (VAS), scoring from 0 (poor) to 100(excellent). Anemia was classified as none/normal (Hb≥12.5 g/dl), mild (10≤Hb<12.5), moderate (9≤Hb<10), severe (8≤Hb<9) or very severe (Hb<8). To assess QoL dynamics, MDS patients repeat this every 6 months . For controls, we used VAS to assess QoL of patients admitted to the Department of Medicine. Results: In total, 126 MDS patients participated: 19, 40, 17, 21 and 29, from normal to very severe anemia, respectively. Fig.1 shows mean QoL of the 5-parameters for all patients (A), and for each individual (B), as well as the mean VAS score for all patients (C) and for each individual (D). Anemic MDS patients show a wide QoL variability (patients with the same Hb behave differently, Fig.1, B, D). Also, note the drop in QoL from moderate to severe anemia (below 9 g/dl, p=0.06, for 5-parameter; p=0.01, for VAS). In the non-MDS controls (n=141), there was impaired QoL in anemic patients as compared to those without anemia (VAS, Figure 2; p=0.02). However, there was no significant difference in QoL among patients with various degrees of anemia. Follow-up QoL data (1 year) were available for 61 MDS patients (Figure 3). 27 (44%) increased Hb. 32 (52%) decreased, and 2 (3%), had no change. Of the 32 who decreased Hb, average QoL deteriorated by -11.88 [95%CI: -17.96, -5.79]; 24 patients (75%, Figure 3, left-lower quadrant) had decreased VAS score; some still had improved QoL (16%), or stayed the same (9%). Of the 27 who increased Hb, average VAS still reduced by -6.48 [-14.08, 1.12]. The minority increased QoL (26%), or stayed the same (19%). Most (56%) still deteriorated in QoL (right-lower). The QoL results using the 5 parameters was consistent. Conclusions: In this preliminary study: 1) Poor QoL in anemic MDS is variable and not linear, suggesting that other factors, in addition to Hb, affect QoL. 2) The sharp drop in QoL with Hb<9 g/dl (Figure 1, A and C from blue to pink), might lead to a therapeutic paradigm shift, with transfusion recommendations for patients with Hb<9. 3) QoL in anemic MDS patients might differ from non-MDS. 4) Anemia treatment and Hb rise are not necessarily associated with improved QoL. Larger studies will help determine QoL in MDS and other anemias and when and how to treat. Figure 1 Figure 1. Disclosures Mittelman: Janssen · Roche · Novartis · Takeda · Medison / Amgen · Neopharm / Celgene / BMS · Abbvie · Gilead: Research Funding; Novartis · Takeda · Fibrogen · Celgene / BMS · Onconova · Geron: Other: Clini; Onconova · Novartis · Takeda · Silence: Membership on an entity's Board of Directors or advisory committees; MDS HUB: Consultancy; Celgene / BMS · Novartis: Speakers Bureau.


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