Fourth Week Of March Research Articles

Retaining the returnee migrant workers: Lessons learned from COVID-19

This paper presents facts and figures of returnee migrant workers in Nepal during the COVID-19 crisis. Nepal, affected by the coronavirus pandemic late after the fourth week of March 2020, the government decided to lockdown due to the appearance of two incidences of infection crossed over one million. Using secondary sources of literature, the paper mainly analyses the facts and figures concerning the COVID-19 crisis and migrant workers' issues. During this period, a severe crisis affected the country with a 75 per cent fall in remittance from the already counted 25 per cent of total gross domestic product. In the beginning, around 1.5 million migrant workers were expected to return by losing jobs in major destinations - India, the Middle East and Malaysia - which is over one-fifth of the total migrant workers abroad. This rate of return however was not recorded to that number. The growing tension of the virus was not limited to the state level only but basically, the individuals losing jobs, killing hopes of getting involved in new jobs and remaining unattended by the state authorities for a longer time amid confusion and dilemma of policies and programmes. Those involved in the informal sectors, particularly the women and other marginalised communities were severely affected when they could not collect food for their families, pay back rents or survive in the place. Reducing the impact of the pandemic, all the stakeholders needed to resume their work by getting proper knowledge and information on the impact of COVID-19. It necessitated concentrating on the immediate priorities such as current living conditions and utilising best practices available and possible in the local communities for reintegration by adopting the tight of the migrant workers. Although the government announced packages to retain nearly one million returnees, this could not properly happen and with dismay, the returned migrants opted to work and jobs abroad.

Occurrence of Aphid, <i>Aphis gossypii</i> Glover and Coccinellids on Isabgol

Aphid Aphis gossypii Glover was found to be the major pest of isabgol in the semi-arid regions of the Rajasthan. The infestation of aphid initiated from 2nd standard meteorological week (SMW) with 6 aphids/ plant and fluctuated till 13th SMW. The peak activity of aphids observed on 8th SMW which gradually reached to the level of 56.13 aphids/ plant and thereafter gradually decreased up to 7.87 aphids/plant in the fourth week of March when the crop matured. The activities of three coccinellid beetles viz. Brumoides suturalis Fabricius, Cheilomenes sexmaculata Fabricius and Coccinella septempunctata Fabricius were also studied, and their peak population was noticed from 8th to 10th SMW (19th February to 5th March, 2022). The significant positive correlation of aphid population was found with bright sunshine and all three species of coccinellids. C. sexmaculata and C. septempunctata have the significant positive correlation with bright sunshine, maximum temperature and average temperature while negative non-significant correlation with relative humidity.

Efficacy of Some Predators and Lecanicillium lecanii Fungus in Controlling of Aphis gossypii (Glover) and Myzus persicae (Sulzer) in Potato Crop

Lokma, N., A.A.A. Saleh, S.A.M. Amer and M F.M. Zawrah. 2023. Efficacy of Some Predators and Lecanicillium lecanii Fungus in Controlling of Aphis gossypii (Glover) and Myzus persicae (Sulzer) in Potato Crop. Arab Journal of Plant Protection, 41(2): 152-160. https://doi.org/10.22268/AJPP-041.2.152160 This study was conducted to evaluate the efficiency of predators and Lecanicillium lecanii suspension as bicontrol agents against Myzus persicae and Aphis gossypii in potato crop, whereas Aphis gossypii had two peaks in the third week of March and April in 2020 and 2021 seasons. In addition, M. persicae had two peaks for both seasons in the fourth week of March and third week of April in 2020 and in the third week of March during 2021. The common predators observed in potato fields were: Coccinella undecimpunctata L., Chrysoperla carnea Steph., Coccinella septumpunctata, Metasyrphus corollae F. and Cydonia vicina isis (Muls.). Regarding potato predators, one peak was found in the second week of March (60 predators/25 leaves) during the 2020 season, and two peaks were found in the third week of March and second week of April (53 and 38 predators/25 leaves, respectively), in 2021 season. On the 8th day after treatment, the entomopathogenic fungus L. Lecanii produced maximum aphid mortality at highest concentration of 108 conidia/ml and 50% concentration of fungal metabolites for both M. persicae and A. gossypii. Meanwhile, L. lecanii 50% metabolites solution had more latent effect by decreasing the longevity and the number of nymphs than when using the spore suspension of 108 conidial/ml. Keywords: A. gossypii, M. persicae, aphid predators, Lecanicillium lecanii, potato.

Effects of Time of Pruning and Plant Bio-Regulators on the Growth, Yield, Fruit Quality, and Post-Harvest Losses of Ber (Ziziphus mauritiana)

Indian jujube or ber (Ziziphus mauritiana Lam.) is a deciduous fruit tree typically cultivated in several semi-arid areas of Asia because of its adaptability to yield-limiting conditions. The present study aimed to assess the effect of four pruning times (i.e., the fourth week of March, second week of April, fourth week of April, and second week of May) and four treatments using stress-mitigating plant bio-regulators (thiourea at 500 ppm and 1000 ppm; salicylic acid at 100 ppm and 150 ppm) as a means to improve both fruit yield and quality post-harvest. To this end, a full factorial experiment lasting two growing seasons was carried out under field conditions in the representative semi-arid region of Rajasthan, the state with the largest production in India. We assessed the vegetative growth of the trees, the fruit size and yield, and some quality parameters (soluble content, acidity, ascorbic acid, and total sugars) as well as the main post-harvest traits (fruit weight loss and spoilage). Overall, pruning during the second week of April had the greatest positive influence on most of the variables studied. For instance, it induced the highest vegetative vigor, allowing the maintenance of relatively higher chlorophyll and relative water content in the leaves. The fruit parameters also responded most positively to the second week of April pruning, a treatment that, compared to the others, induced a higher diameter; a higher amount of TSS (19.6 °Brix), ascorbic acid (86.5 mg/100 g), and total sugar (10.4%); and a better post-harvest shelf-life. Among the plant bio-regulators, the application of thiourea at 1000 ppm had the highest positive influence on the growth parameters, yield, quality, and reduction in spoilage post-harvest. The differences between the doses of PBRs were limited.

From COVID-19 to Influenza-Real-Life Clinical Practice in a Pediatric Hospital.

The COVID-19 pandemic, through the restrictions and the non-pharmaceutical interventions implemented, has importantly impacted the circulation and epidemiology of respiratory viruses. Specifically, the 2020/21 season was entirely dominated by SARS-CoV-2, while influenza activity reached an all-time low, despite initial warnings that a double concurrent epidemic could be possible. The current season, 2021/22, started with the shift of circulating SARS-CoV-2 variants from delta to omicron, which then rapidly spread globally, as most countries, including Romania, removed all restrictions and compulsory non-pharmaceutical interventions. In this report we present the clinical reality observed in March 2022 in a tertiary paediatric hospital in Bucharest, Romania, where we observed a sudden surge in influenza cases, after two consecutive years (March 2020 to March 2022) when influenza had stopped circulating in our country. Thus, in March 2022 the positivity rate of rapid influenza antigen tests unexpectedly increased to 33.5%, paralleled by a decrease to 7.5% in the positivity rate of rapid SARS-CoV-2 antigen tests. This significant increase in the influenza attack rate was observed from the first week (14.9% positivity rate), through the fourth week of March (42.1% positivity rate, p < 0.001), while the COVID-19 attack rate displayed a significant decreasing trend (from 11.2% to 4.8%, p < 0.001). These data serve as a warning about relaxing restrictions in a precipitous approach with minimised vigilance. The evolution of these observations needs to be followed very carefully in all countries, particularly in settings where epidemiological interactions and non-pharmaceutical interventions have so far led to the extensive circulation of only one of these viruses, and we should now be prepared to perform a correct differential diagnosis between influenza and COVID-19, in order to ensure the best quality of care and personalized management of each case of respiratory infection. The results of active influenza surveillance studies for the whole 2021/22 season are awaited, in order to quantify the joint influenza—COVID-19 burden among children.

Timing and volume of information produced for the Otolaryngologist during the COVID-19 pandemic in the UK: A review of the volume of online literature.

BackgroundThe SARS‐CoV‐2 was first reported in December 2019 in Wuhan, China and has been declared a pandemic in March 2020. COVID‐19 has caused unprecedented and lasting biopsychosocial effects worldwide. All healthcare professionals have faced life‐threatening risks by attending their daily jobs. The daily emergence of advice and guidelines was necessary to ensure the safety of patients and staff. To this effect, all elective services came to a halt to preserve hospitals’ capacity for dealing with the sickest. This retrospective, descriptive review aims to assess the volume and timing of the advice released specifically relevant to UK ENT specialists.MethodsTwo separate searches were performed. One involved online advice published in English by international, national and ENT‐specific organisations between January 1 and May 31. The date, title, source, type of advice and link to the advice were recorded in Excel. The resources were analysed per week of publication. A second separate search for peer‐reviewed publications was conducted using PubMed Central and Cochrane databases.FindingsCOVID‐19‐related guidance was considered, of which 175 were identified. 52/175 (29.7%) articles were published by international organisations. 56/175 (32%) were produced by national organisations, and 67/175 (38.28%) were produced by ENT specific organisations. The peak guidance production took place in the third and fourth week of March (16/03/2020‐29/03/2020) with 72/175 publications. Of these, 27/70 came from the international category, 17/70 from national bodies and 26/70 from ENT‐specific organisations. 13 863 total publications relating to COVID‐19 were found using PubMed and Cochrane search strategies; 76% were relevant to ENT.ConclusionThe challenges faced by ENT relate to the unprecedented, sudden and daily changes to clinical practice. Multiple bodies interpreted the guidance, giving an opportunity for confusion and delay in treatments for patients. Implementing a system with clear lines of communication and dissemination of information will improve our response to future pandemic events whilst maintaining a commercial awareness to better use the human and financial resources of an already financially restricted NHS.

Letter: Implementation of a Neurosurgery Telehealth Program Amid the COVID-19 Crisis-Challenges, Lessons Learned, and a Way Forward.

Letter: Implementation of a Neurosurgery Telehealth Program Amid the COVID-19 Crisis-Challenges, Lessons Learned, and a Way Forward.

Knowledge and understanding among medical imaging professionals in India during the rapid rise of the covid-19 pandemic.

During the first week of March,2020 the surge of coronavirus disease (COVID-19) cases reached all over the globe with more than 100,000 cases. Healthcare national and international authorities have already initiated awareness and lockdown activities. A poor understanding of the disease among medical imaging professionals (MIPs) may result in rapid spread of infection. This study aimed to investigate the knowledge and understanding of MIPs about COVID-19. A cross-sectional, web-based study was conducted among MIPs about COVID- 19 during the fourth week of March 2020. An online sample of MIPs was successfully recruited via the authors’ networks in India using data collection tool – write google forms. A self-developed online KAP questionnaire was completed by the participants. The knowledge and understanding questionnaire consisted questions regarding the clinical characteristics and transmission routes of COVID-19. Assessment on practices towards COVID-19 included questions on techniques while imaging against COVID-19 suspected patients. Of 700 participants, a total of 550 MIPs completed the survey (response rate: 78.57%); 56.7% were males, 85.4.1% were aged 17–26 years, and most were undergraduates (77.6%) and postgraduates (17.1%). Regarding COVID-19, most of the participants answered correctly (95.5%) on symptoms, (84.4%) time interval for visible symptoms, (98.0%) transmission and (44%) airborne transmission respectively. A significant proportion of MIPs (36.4%) had poor knowledge about wearing multiple masks as an effective measure against coronavirus infection. Most of the respondents (48.5%) incorrectly considered X-ray as the reliable method of diagnosis for suspected COVID-19 patients. 44.6% of the respondents lacked knowledge about the steps involved in hand washing technique which is one of the most important safety practice methods in medical imaging to prevent spread of infection. Factors such as age and occupation were associated with inadequate knowledge and poor perception of COVID-19. As the current global threat of COVID-19 continues to emerge, it is crucial and critical to improve the knowledge and understanding of MIPs. Educational videos and live webinars are urgently needed to reach MIPs and further detailed studies are the need of the hour.Electronic supplementary materialThe online version of this article (10.1007/s12553-020-00437-2) contains supplementary material, which is available to authorized users.

Evaluating Dry Matter Production and Grain Yield of Dual-Purpose Winter Wheat Using Field Experiment and Modelling

The potential of a winter wheat (Triticum aestivum L.) cultivar Wedgetail to provide grazing and grain yield under different sowing times, grazing times, and watering regimes, under current and future climate, was investigated using field experiment and simulation modelling. For the field experiment, there were two watering treatments (unirrigated (D) and irrigated (I)) and four simulated grazing treatments (ungrazed, simulated grazed at growth stage (GS) 25, simulated grazed at growth stage (GS) 32, and grazed at both GS 25 and GS 32). These were designated as D0, D1, D2, and D3, respectively, for the unirrigated treatment and I0, I1, I2, and I3, respectively, for the irrigated treatment. It was found that the soil water depletion was significantly higher (p &lt; 0.05) for the irrigated/ungrazed treatment than that for the simulated grazed treatment. The crop simulated grazed at GS 25 recovered quicker than the crop grazed at GS 32, especially for the unirrigated treatment. As the sowing time is delayed, above-ground dry matter (AGDM) production decreases. For D2 and D3, the amount of simulated grazed AGDM was 3.46 t ha−1 and 3.55 t ha−1, respectively. For I2 and I3, the amount of simulated grazed AGDM was 4.73 t ha−1 and 4.34 t ha−1, respectively. For D1, simulated grazing increased grain yield by 7%, while for D2 and D3, it increased by 18% and 24%, respectively. For I1, simulated grazing reduced grain yield by 16%, while for I2 and I3, it decreased by 42% and 42%, respectively. Simulation using the Agricultural Production Systems sIMulator (APSIM) showed that, for winter wheat sown in the second week of March, the maximum AGDM expected one in two years at the ends of May, June, and July is 4.5 t ha−1, 5.8 t ha−1, and 6.8 t ha−1, respectively. If the crop is sown mid-April, these values are 0.8 t ha−1, 2.2 t ha−1, and 4.3 t ha−1, respectively. Yield did not show response to times of sowing from March to early April. The maximum value reached was about 4.5 t ha−1 when sown in the fourth week of March, after which it started decreasing and reached the lowest value of about 4.1 t ha−1 when sown by the end of May. The total above-ground dry matter (AGDM) obtained by grazing earlier during the feasible grazing period and again towards the end of this period was not significantly different from grazing only once towards the end of this period. The simulation results showed that winter wheat Wedgetail flowering date was less sensitive to sowing time and that yield did not show a significant response to times of sowing, with the maximum occurring for the fourth week of March sowing and the lowest for the fourth week of May sowing.

Relationship Between Gestational Age and Severity of Gingivitis

Increased levels of the hormones estrogen and progesterone in the blood during pregnancy can cause gingivitis due to vascular changes that cause the gingiva to become more sensitive especially to toxins and other irritants, such as plaques and calculus, which causes the gingiva to become easily inflamed. Pregnancy can also aggravate gingivitis due to the excessive inflammatory response of the gingiva to dental plaque and hormonal changes that occur during pregnancy. This study aims to determine the differences in the degree of gingivitis in pregnant women in each trimester of gestational age. This study was a cross-sectional study conducted in April 2019 on 80 pregnant women with gingivitis who examined their pregnancies at the Puskesmas Merdeka Palembang during the fourth week of March 2019. The relationship between the degree of gingivitis in each trimester of pregnancy was analyzed using Fisher's exact test with 95% confidence interval. The results showed that gingivitis was found most frequently in third trimester pregnancy (47.5%) and mild gingivitis, mostly experienced by pregnant women in trimester II pregnancy (52.6%), while moderate and severe gingivitis was more experienced by trimester pregnant women III (50% and 81.8%). The statistical test results showed a significant relationship between the gestational age and severity of gingivitis (p 0.05). It can be concluded that increasing gestational age is related to the increasing severity of gingivitis.

Spatial distribution of cabbage aphid, Brevicoryne brassicae (L.) and its parasitoid,Diaeretiella rapae (Mc Intosh) under sub-temperate conditions of Himachal Pradesh, India

Cabbage aphid, Brevicoryne brassicae (L) (Aphididae: Hemiptera) is one of the most serious pest of cauliflower throughout the world. Knowledge of spatial distribution is important for developing an effective sampling plan and ultimately for IPM strategies for a given pest. In the present study spatial distribution of B. brassicae and its parasitoid, Diaeretiella rapae (Mc lntosh) (Braconidae: Hymenoptera) was studied on cauliflower ( Brassica oleracea var botrytis ) under sub-temperate conditions of India during 2017. Both B. brassicae and D. rapae assumed activity in the fourth week of January and remained active till May end with peak activity during fourth week of March, 2017. Dispersion indices like variance to mean ratio (Iƒ 2 /X), David-Moore index (IDM = Iƒ 2 /X-1), mean crowding (X*), Lloyd’s mean crowding index (X*/X) and ‘k’ of negative binomial indicated that both the aphid and the parasitoid followed negative binomial distribution throughout the cropping season, Taylor’s power equation was Iƒ 2 = 1.7013X0.5314 for B. brassicae and Iƒ 2 = 2.2057X1.4467 for D. rapae , while Iwao’s patchiness regression equation was X*= 32.0099+1.7947X and X*= -2.0678+2.2746X for B. brassicae and D. rapae , respectively. Optimum number of samples required varied with the mean density and the desired precision level for both the aphid and the parasitoid.

Seasonal incidence of whitefly,Bemisia tabaci(Aleyrodidae: Hemiptera) on different genotypes of okra, correlated with ecological parameters

Studies revealed that the incidence of the whitefly started in the third week of February and persisted throughout the season, on all the varieties. The varieties Arka Abhay (V1) and VRO-5 (V4), showed minimum build-up of whitefly population. The incidence started from the second and fourth week of March and, reached its peak in the second and first week of April and continued to decline till the maturation of the crop on the varieties, Arka Abhay (V1) and VRO-5 (V4) respectively. The pest incidence was found to be maximum, when maximum and minimum temperature ranged from 41.10 to 20.70°C and 40.50 to 18.30°C and relative humidity ranged from 61 to 15% and 57 to 14% on the varieties, Arka Abhay (V1) and VRO-5 (V4) respectively. Positive and significant correlation with maximum temperature and negative and significant correlation with maximum relative humidity was observed with whitefly population on both the varieties.

SURVEY THE NEUROPTEROUS PREDATORS AND THE RELATIVE ABUNDANCE OF Chrysoperla carnea (STEPH.) AND Chrysopa septempunctata WESM. BY USING A LIGHT TRAP AT MANSOURA DISTRICT

A survey of certain neuropterous predators and the relative abundance of the important neuropterous predatory insects were studied by using a light trap during two successive years at Mansoura district. The obtained results recorded four neuropteruos predators trapped during the two years of study. These species belonging to two families : Chrysopidae and Myrmeleonidae. These predators were namely: Chrysoperla carnea (Steph.) ; Chrysopa septempunctata Wesm.; Cueta variegata Klug. and Palpares cephalotes Klug. The dominant species was C. carnea during the two years of investigation. The data showed that C. carnea had six peaks in the first year and five peaks in the second year of study. These peaks were recorded in the fourth week of March; fourth week of April; first week of June; third week of July; third week of August and second week of October; while in the second year these peaks were recorded in the first week of April; first week of June , first week of July, first week of August and fourth week of September, respectively. The obtained data revealed that C. septempunctata had four peaks in the first years and three peaks in the second years. These peaks were recorded in the first week of June, third week of July, fourth week of August and second week of October, respectively in the first year, Meanwhile, these peaks were found in the second year of study, in the first week June, first week of July and fourth week of August. The statistical analysis assured that, there was a highly positive significant correlations between the biweekly catch of C. carnea and C. septempunctata and temperature parameters during the two years of study. While, the relative humidity parameters had insignificant effect on the population density of the two predators during the two years of investigations.

Systematic Review of Controlled Clinical Trials on the Use of Ursodeoxycholic Acid for the Prevention of Hepatic Veno-occlusive Disease in Hematopoietic Stem Cell Transplantation

Hepatic veno-occlusive disease (HVOD) is a serious life-threatening complication of hematopoietic stem cell transplantation (HSCT). Currently, there is no optimal therapeutic strategy and preventive measures are ill-defined. Ursodeoxycholic acid (UA) is well-tolerated oral medication that has been associated with possible benefit as a prophylactic agent. We sought to summarize and quantify the clinical effects of prophylactic UA in the context of HSCT. We undertook a systematic review of studies addressing the use of UA as monotherapy or in combination with other agents in patients undergoing HSCT. The Search Strategy included MEDLINE (1966 to fourth week of March 2006), EMBASE (1980 to fourth week of March 2006), all EBM Reviews (fourth quarter of 2005), Ovid Healthstar (1966 to fourth week of March 2006), and Google Scholar on March 20, 2006. Six studies, 4 randomized clinical trials and 2 historically controlled studies, representing 824 patients were included in the review. Three randomized clinical trials comparing prophylactic UA with no treatment demonstrated reduced proportion of HVOD (relative risk [RR], 0.34; 95% confidence interval [CI], 0.17-0.66). When the analysis was limited to higher-quality studies, the beneficial effect of UA remained significant (RR, 0.36; 95% CI, 0.15-0.90). Transplant-related mortality was also reduced with the prophylactic use of UA (RR, 0.58; 95% CI, 0.35-0.95). UA did not significantly attenuate the outcomes of acute graft-versus-host disease (RR, 0.76; 95% CI, 0.53-1.09), relapse (RR, 0.77; 95% CI, 0.46-1.31), or overall survival (RR, 1.22; 95 % CI, 0.96-1.54). UA appears effective for HVOD prophylaxis in patients undergoing HSCT and should be considered as a prevention strategy by HSCT centers to reduce HVOD.

島原半島の春作ジャガイモ圃場におけるＰｏｔａｔｏ ｖｉｒｕｓ Ｙの感染時期および媒介虫の飛来時期について

Potato virus Y (PVY) causes serious yield loss to seed potato production in the world. We investigated the seasonal occurrence of four aphid vectors and the infection period of PVY in potato fields in the Shimabara peninsula. Aphis gossypii, Myzus persicae, and Aulacorhtum solani first appeared in the fourth week of March in 2003 and 2004 and in the first week of April in 2005. They were collected when the mean weekly temperature was above 12°C. Macrosiphum euphorbiae was not collected during the survey periods. Virus infection started with the emergence of these vectors in 2005, although it started two or three weeks later in 2003 and 2004. The PVY-infection ratio increased between the fourth week of April and the first week of May. These results suggested that harvesting tubers by the fourth week of April could reduce the PVY infection.

Time of Emergence of Eight Weed Species

Under irrigated field conditions at Prosser, WA, Russian thistle [Salsola kali(L.) var.tenuifoliaTausch. ♯3SASKR] began to emerge by mid-March each year and usually had completed its emergence by May 1. Common lambsquarters (Chenopodium albumL. ♯ CHEAL) was the next to appear, usually during the third or fourth week of March. Barnyardgrass [Echinochloa crus-galli(L.) Beauv. ♯ ECHCG], redroot pigweed (Amaranthus retroflexusL. ♯ AMARE), hairy nightshade (Solarium sarrachoidesSendt. ♯ SOLSA), black nightshade (5.nigrumL. ♯ SOLNI), eastern black nightshade (S. ptycanthumDun.), and cutleaf nightshade (S. triflorumNutt. ♯ SOLTR) generally began to emerge during the first 2 weeks of April and emergence generally peaked mid-April to mid-May. Russian thistle and cutleaf nightshade had the most restricted emergence patterns, whereas seedlings of common lambsquarters, redroot pigweed, hairy nightshade, and black nightshade emerged each month from April through September. Shallow tillage at monthly intervals increased the overall emergence of common lambsquarters, redroot pigweed, black nightshade, and eastern black nightshade; decreased the emergence of barnyardgrass; and had no effect on the emergence of Russian thistle, cutleaf nightshade, or hairy nightshade.

Microscopic spectral features in solar decametric bursts and coronal irregularities

A crossed Yagi antenna array at 35 MHz was employed in conjunction with a polarization switch so as to enable spectral observations of solar noise storm activity in R and L polarizations. Intense decametric solar noise storms were recorded during the third week of November 1975 and fourth week of March 1976 with the help of a high resolution spectroscope operating near 35 MHz. The paper describes some of the new microscopic spectral features observed during these two noise storms. Three sets of high resolution dynamic spectra of decametric solar bursts, two of which are explained in terms of induced scattering of Langmuir waves by thermal ions and the third in terms of additional propagation effects through dense coronal irregularities, are presented. The microscopic bursts, classified as ‘inverted U’ ‘U’ and ‘dots’, represent small-scale (∼104 km) phenomena with durations of less than a second. Some burst spectra appear as chain of ‘dots’ with individual bandwidths ∼40 kHz and durations ∼ 0.3 sec. It is suggested that the bandwidth of such ‘dot’ emissions (∼40 kHz) provides an evidence that they might indeed be generated by the process of induced scattering of plasma waves which predicts emission bandwidth ∼f × 10−3, where f is the center frequency. Some bursts are observed as a chain of ‘striations’ showing curvature along the frequency axis which is attributed to dispersion in propagation delays through the dense coronal irregularities.