An Experiment with DDT against Pests of stored Products

1947 ◽  
Vol 38 (2) ◽  
pp. 347-352 ◽  
Author(s):  
B. M. Jones

(1) The experiment was carried out on a short term basis due mainly to the limited time available for stored food products work, but it does show the possibilities of giving to the carrier medium an “adhesive” quality for the purpose of retaining an external layer of DDT upon bagged commodities.(2) The increased activity at night of insects attacking stored food is interesting and the movement of insect densities in bags containing foodstuffs needs further detailed investigation. It does seem that a very high percentage of adult beetles will migrate to the surface of bags from inside the contained foodstuffs, and this makes it possible to achieve a fair measure of control by coating bags with a deposit of DDT.(3) When a concentrate mist of a DDT emulsion-gum arabic solution is allowed to settle upon a bag surface, there is no detectable penetration of DDT through the sacking texture and therefore no danger of contaminating the contained foodstuffs.(4) A deposit of such a DDT film, at a concentration rate of 50 mgm. DDT/sq.ft. upon a jute bag surface, remains appreciably toxic to Tribolium castaneum, Calandra oryzae, Rhizopertha dominica and Laemophloeus spp. for a period of approximately 60 days.

Author(s):  
Michael A. Cohn ◽  
Barbara L. Fredrickson

Positive emotions include pleasant or desirable situational responses, ranging from interest and contentment to love and joy, but are distinct from pleasurable sensation and undifferentiated positive affect. These emotions are markers of people's overall well-being or happiness, but they also enhance future growth and success. This has been demonstrated in work, school, relationships, mental and physical health, and longevity. The broaden-and-build theory of positive emotions suggests that all positive emotions lead to broadened repertoires of thoughts and actions and that broadening helps build resources that contribute to future success. Unlike negative emotions, which are adapted to provide a rapid response to a focal threat, positive emotions occur in safe or controllable situations and lead more diffusely to seeking new resources or consolidating gains. These resources outlast the temporary emotional state and contribute to later success and survival. This chapter discusses the nature of positive emotions both as evolutionary adaptations to build resources and as appraisals of a situation as desirable or rich in resources. We discuss the methodological challenges of evoking positive emotions for study both in the lab and in the field and issues in observing both short-term (“broaden”) and long-term (“build”) effects. We then review the evidence that positive emotions broaden perception, attention, motivation, reasoning, and social cognition and ways in which these may be linked to positive emotions' effects on important life outcomes. We also discuss and contextualize evidence that positive emotions may be detrimental at very high levels or in certain situations. We close by discussing ways in which positive emotions theory can be harnessed by both basic and applied positive psychology research.


Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1695
Author(s):  
Constantin-Octavian Andrei ◽  
Sonja Lahtinen ◽  
Markku Poutanen ◽  
Hannu Koivula ◽  
Jan Johansson

The tenth launch (L10) of the European Global Navigation Satellite System Galileo filled in all orbital slots in the constellation. The launch carried four Galileo satellites and took place in July 2018. The satellites were declared operational in February 2019. In this study, we report on the performance of the Galileo L10 satellites in terms of orbital inclination and repeat period parameters, broadcast satellite clocks and signal in space (SiS) performance indicators. We used all available broadcast navigation data from the IGS consolidated navigation files. These satellites have not been reported in the previous studies. First, the orbital inclination (56.7±0.15°) and repeat period (50680.7±0.22 s) for all four satellites are within the nominal values. The data analysis reveals also 13.5-, 27-, 177- and 354-days periodic signals. Second, the broadcast satellite clocks show different correction magnitude due to different trends in the bias component. One clock switch and several other minor correction jumps have occurred since the satellites were declared operational. Short-term discontinuities are within ±1 ps/s, whereas clock accuracy values are constantly below 0.20 m (root-mean-square—rms). Finally, the SiS performance has been very high in terms of availability and accuracy. Monthly SiS availability has been constantly above the target value of 87% and much higher in 2020 as compared to 2019. Monthly SiS accuracy has been below 0.20 m (95th percentile) and below 0.40 m (99th percentile). The performance figures depend on the content and quality of the consolidated navigation files as well as the precise reference products. Nevertheless, these levels of accuracy are well below the 7 m threshold (95th percentile) specified in the Galileo service definition document.


2013 ◽  
Vol 15 (2) ◽  
pp. 101-110
Author(s):  
Joana Sender ◽  
Weronika Maślanko

ABSTRACT The Łęczna-Włodawa Plain, known also as the Łęczna-Wlodawa Lakeland, lies within the territory of the largest subregion of the Polesie region, covering over 1,300 km2. The main interest of the Łęczna-Włodawa Lakeland is that it is the oldest in the Central European Lowlands group of about 68 lakes. Among such a large number of lakes there exist all trophic types. However, since the late 1950’s, enormous dynamics of change associated with the disappearance of oligo- and mesotrophic lakes and their transformation into eutrophic, even hypertrophic, lakes have been observed. One of the biocenotic elements of the lakes, which are indicators of these changes, is aquatic plants. The aim of this study was to determine the macrophyte structure of Piaseczno Lake and changes of land use in its surroundings. Piaseczno Lake still represents very high natural values. A reduction in the number of macrophyte communities, which occurred especially in 2008, was a consequence of the fast-growing recreation infrastructure. From 1976 until 2010 an area of recreation infrastructure in the studied area increased more than 3.5 times, and in the built-up area more than five times, as well as a doubling of the total length of the roads. Meanwhile the surface area of wetlands and peatbogs significantly decreased - more than 11 times. Long-term changes in the structure of the macrophyte communities show that the number of communities has varied in each year, probably as a consequence of changes in landuse. Analysis showed changes to the surfaces inhabited by macrophytes, which have decreased significantly over only four years, by more than 25%. However, the proportion of rush communities has increased.


2020 ◽  
Author(s):  
Eyal Peer ◽  
Yuval Feldman

A common dilemma in regulation is determining how much trust authorities can place in people’s self-reports, especially in regulatory contexts where the incentive to cheat is very high. In such contexts, regulators, who are typically risk averse, do not readily confer trust, resulting worldwide in excessive requirements when applying for permits, licenses, and the like. Studies in behavioral ethics have suggested that asking people to ex-ante pledge to behave ethically can reduce their level of dishonesty and noncompliance. However, pledges might also backfire by allowing more people to cheat with no real sanctions. Additionally, pledges’ effects have only been studied in one-shot decision making, and they may only have a short-term effect that could decay in the long run, leading to an overall erosion of trust. We explored the interaction of pledges with sanctions and the decay of their effects on people’s honesty by manipulating whether pledges were accompanied by sanctions (fines) and testing their impact on sequential, repeated ethical decisions. We found that pledges considerably and consistently reduced dishonesty, and this effect was not crowded out by the presence of fines. Furthermore, pledges seem to exert an effect on most people, including those who are relatively less inclined to follow rules and norms. We conclude that pledges could be an effective tool for the behavioral regulation of dishonesty, reduce the regulatory burden, and build a more trusting relationship between government and the public, even in areas where incentives and opportunities to cheat are high.


2021 ◽  
Author(s):  
Jung Woo Choi ◽  
Jin-Kyu Cho ◽  
Sang Soo Lee ◽  
Jae Heon Kim ◽  
Hankyu Jeon ◽  
...  

Abstract Background Acute-on-chronic liver failure (ACLF) is a widely recognized concept in which acute decompensation (AD) in patients with cirrhosis results in organ failures and high short-term mortality. However, few studies reflecting the various etiologies of cirrhosis are available. We aimed to investigate the clinical features of patients with hepatitis C virus (HCV)-related ACLF. Methods Between January 2005 and December 2018, 109 HCV-related cirrhosis patients who were hospitalized for AD (ascites, hepatic encephalopathy, gastrointestinal hemorrhage, and/or bacterial infection) were enrolled for ACLF defined by European Association for the Study of the Liver (EASL). Results ACLF developed in 35 patients (32.1%) on admission. Eight patients had ACLF grade 1, eight had ACLF grade 2, and 19 had ACLF grade 3. The 28-day and 90-day mortality rates were very low (2.7% and 5.4%, respectively) in patients without ACLF and very high (60.0% and 74.3%, respectively) in those with ACLF. In patients with HCV-related ACLF, the prevalence of liver failure was very low (17.1%), whereas that of kidney failure was very high (71.4%) compared to previous studies on hepatitis B virus-related ACLF and alcohol-related ACLF. Compared with all other prognostic scores, Chronic liver failure Consortium Organ Failure score most accurately predicted 90-day mortality, with an area under the receiver operator characteristic of 0.921. Conclusions HCV-related ACLF has unique clinical characteristics that are distinct from hepatitis B virus-related and alcohol-related ACLF. ACLF defined by EASL can be useful in predicting short-term mortality in HCV-related cirrhosis.


1996 ◽  
Vol 81 (3) ◽  
pp. 1379-1387 ◽  
Author(s):  
K. Chin ◽  
M. Ohi ◽  
M. Fukui ◽  
H. Kita ◽  
T. Tsuboi ◽  
...  

We investigated the effects of an intellectual task on posthyperventilation (PHV) breathing by using a video game. Eight normal subjects were placed in a supine positions. The game task by itself led to increase ventilation compared with the control tasks via an increase in the average inspiratory flow rate (P < 0.01) and the respiratory frequency (P < 0.001). After hypocapnic voluntary hyperventilation (VHV), the task led to a decrease in the 1-min PHV breathing level compared with the control tasks after VHV [after VHV, first 60 s average minute ventilation while watching television and while playing a video game are 5.54 +/- 2.91 (SD) and 2.05 +/- 1.40 l/min, respectively; P < 0.01]. Only one subject showed PHV apnea for at least 10 s during the control protocol, whereas seven of the same eight subjects showed PHV apnea while performing the task. After isocapnic VHV, the task still led to a decrease in PHV breathing compared with the control tasks. However, this decrease was smaller than in the hypocapnic studies and was only significant during the first 15 s of recovery. These results suggest that increased activity in the higher centers of the central nervous system has an inhibitory effect on PHV breathing at a time when the effects of short-term potentiation after VHV, hypocapnia, and perhaps other mechanisms would be expected to be acting on breathing.


2007 ◽  
Vol 201 ◽  
pp. 4-7
Author(s):  
Martin Weale

The July interest rate increase has taken the Bank of England's Base Rate to the highest value for six years. In figure 1 we show the forward estimates for the nominal short-term interest rate taken from the Bank of England's yield curve tables for both government debt and liabilities of commercial banks. These are in effect market forecasts of the short-term rate produced in the past. The graph shows that the market has been taken somewhat by surprise by rising short-term interest rates. Two years ago the market was forecasting a rate of around 4 per cent per annum for July 2007. Nor were the probabilities the market gave to an interest rate of 5.75 per cent per annum very high. Twelve months ago the market in financial options implied that the chance of the rate exceeding 5.66 per cent per annum was only 15 per cent. Even in January of this year the chance of it reaching its current level or higher was put at less than 25 per cent. The National Institute cannot claim a substantially better record at forecasting interest rates. We normally use market expectations, as calculated from the yield curve, to provide exogenous forecasts as input into our model in the short term.


1973 ◽  
Vol 24 (6) ◽  
pp. 913 ◽  
Author(s):  
RC Clark ◽  
OE Budtz-Olsen ◽  
RB Cross ◽  
P Finnamore ◽  
PA Bauert

Urinary and faecal phosphorus excretion were measured in five sheep for 4 days after acute intravenous infusion of 3.38 g of phosphorus as potassium dihydrogen phosphate. Urinary phosphorus excretion was increased for 12 hr after the infusion, but urinary phosphorus output was small compared with the marked increase in faecal phosphorus output. The increase in faecal phosphorus excretion coincided with and followed the appearance in the faeces of Cr-EDTA, which had been introduced into the rumen as a marker at the time of the phosphate infusion. This suggests that secretion of phosphorus into gut regions below the reticulo-rumen is not quantitatively altered in response to intravenous phosphorus loading, and that phosphorus absorption is also unaffected (at least not on a short-term basis). The additional phosphorus entered the alimentary canal at the level of the reticulo-rumen, and it was deduced that this occurred predominantly via the salivary glands. Persistence of the increase in faecal phosphorus excretion for some time after the Cr-EDTA marker had been cleared emphasizes the importance of the phosphorus recirculation system to ruminants like the sheep.


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