upper limits
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2022 ◽  
Vol 924 (2) ◽  
pp. 51
Author(s):  
Zara Abdurashidova ◽  
James E. Aguirre ◽  
Paul Alexander ◽  
Zaki S. Ali ◽  
Yanga Balfour ◽  
...  

Abstract Recently, the Hydrogen Epoch of Reionization Array (HERA) has produced the experiment’s first upper limits on the power spectrum of 21 cm fluctuations at z ∼ 8 and 10. Here, we use several independent theoretical models to infer constraints on the intergalactic medium (IGM) and galaxies during the epoch of reionization from these limits. We find that the IGM must have been heated above the adiabatic-cooling threshold by z ∼ 8, independent of uncertainties about IGM ionization and the radio background. Combining HERA limits with complementary observations constrains the spin temperature of the z ∼ 8 neutral IGM to 27 K 〈 T ¯ S 〉 630 K (2.3 K 〈 T ¯ S 〉 640 K) at 68% (95%) confidence. They therefore also place a lower bound on X-ray heating, a previously unconstrained aspects of early galaxies. For example, if the cosmic microwave background dominates the z ∼ 8 radio background, the new HERA limits imply that the first galaxies produced X-rays more efficiently than local ones. The z ∼ 10 limits require even earlier heating if dark-matter interactions cool the hydrogen gas. If an extra radio background is produced by galaxies, we rule out (at 95% confidence) the combination of high radio and low X-ray luminosities of L r,ν /SFR > 4 × 1024 W Hz−1 M ⊙ − 1 yr and L X /SFR < 7.6 × 1039 erg s−1 M ⊙ − 1 yr. The new HERA upper limits neither support nor disfavor a cosmological interpretation of the recent Experiment to Detect the Global EOR Signature (EDGES) measurement. The framework described here provides a foundation for the interpretation of future HERA results.


2022 ◽  
Vol 21 (12) ◽  
pp. 309
Author(s):  
Armine Amekhyan ◽  
Seda Sargsyan ◽  
Arman Stepanian

Abstract We consider different observational effects to test a modified gravity approach involving the cosmological constant in the common description of dark matter and dark energy.We obtain upper limits for the cosmological constant by studying the scaling relations for 12 nearby galaxy clusters, the radiated power from gravitational waves and the Tully-Fisher relation for super spiral galaxies. Our estimations reveal that, for all these cases, the upper limits for Λ are consistent with its actual value predicted by cosmological observations.


2022 ◽  
Vol 924 (1) ◽  
pp. 21
Author(s):  
Mark A. Siebert ◽  
Kin Long Kelvin Lee ◽  
Anthony J. Remijan ◽  
Andrew M. Burkhardt ◽  
Ryan A. Loomis ◽  
...  

Abstract We report a systematic study of all known methyl carbon chains toward TMC-1 using the second data release of the GOTHAM survey, as well as a search for larger species. Using Markov Chain Monte Carlo simulations and spectral line stacking of over 30 rotational transitions, we report statistically significant emission from methylcyanotriacetylene (CH3C7N) at a confidence level of 4.6σ, and use it to derive a column density of ∼1011 cm−2. We also searched for the related species, methyltetraacetylene (CH3C8H), and place upper limits on the column density of this molecule. By carrying out the above statistical analyses for all other previously detected methyl-terminated carbon chains that have emission lines in our survey, we assess the abundances, excitation conditions, and formation chemistry of methylpolyynes (CH3C2n H) and methylcyanopolyynes (CH3C2n-1N) in TMC-1, and compare those with predictions from a chemical model. Based on our observed trends in column density and relative populations of the A and E nuclear spin isomers, we find that the methylpolyyne and methylcyanopolyyne families exhibit stark differences from one another, pointing to separate interstellar formation pathways, which is confirmed through gas–grain chemical modeling with nautilus.


2022 ◽  
Vol 82 (1) ◽  
Author(s):  
Sai Wang ◽  
Zhi-Chao Zhao

AbstractTwo gravitational wave events, i.e. GW200105 and GW200115, were observed by the Advanced LIGO and Virgo detectors recently. In this work, we show that they can be explained by a scenario of primordial black hole binaries that are formed in the early Universe. The merger rate predicted by such a scenario could be consistent with the one estimated from LIGO and Virgo, even if primordial black holes constitute a fraction of cold dark matter. The required abundance of primordial black holes is compatible with the existing upper limits from microlensing, caustic crossing and cosmic microwave background observations.


Children ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 29
Author(s):  
Ahmad Kantar ◽  
Manuela Seminara ◽  
Marta Odoni ◽  
Ilaria Dalla Verde

A 17-year-old male was referred to the emergency room with sharp abdominal pain, pallor, sweating, and vomiting 12 h after the administration of his first Pfizer-BioNTech vaccine for coronavirus disease 2019 (COVID-19). He had abdominal pain, an increase in serum lipase value of > 3 times the upper limits of normal, and magnetic resonance imaging (MRI) findings consistent with acute mild pancreatitis (AP). He was started on treatment with fluid therapy and non-steroidal anti-inflammatory drugs for pain management, after which he recovered rapidly and was discharged on the fourth day after hospitalization. The available data are difficult to interpret as AP is a relatively frequent disease, but its occurrence after vaccination seems extremely rare. Although it is a rare event, AP should be considered after COVID-19 vaccination, especially in those exhibiting abdominal tenderness and vomiting, which should be promptly treated and adequately investigated.


Mathematics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 108
Author(s):  
Olha Chernukha ◽  
Yurii Bilushchak ◽  
Natalya Shakhovska ◽  
Rastislav Kulhánek

We propose and justify a numerical method for computing the double integral with variable upper limits that leads to the variableness of the region of integration. Imposition of simple variables as functions for upper limits provides the form of triangles of integration region and variable in the external limit of integral leads to a continuous set of similar triangles. A variable grid is overlaid on the integration region. We consider three cases of changes of the grid for the division of the integration region into elementary volumes. The first is only the size of the imposed grid changes with the change of variable of the external upper limit. The second case is the number of division elements changes with the change of the external upper limit variable. In the third case, the grid size and the number of division elements change after fixing their multiplication. In these cases, the formulas for computing double integrals are obtained based on the application of cubatures in the internal region of integration and performing triangulation division along the variable boundary. The error of the method is determined by expanding the double integral into the Taylor series using Barrow’s theorem. Test of efficiency and reliability of the obtained formulas of the numerical method for three cases of ways of the division of integration region is carried out on examples of the double integration of sufficiently simple functions. Analysis of the obtained results shows that the smallest absolute and relative errors are obtained in the case of an increase of the number of division elements changes when the increase of variable of the external upper limit and the grid size is fixed.


Nutrients ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 43
Author(s):  
Masayuki Okuda ◽  
Aya Fujiwara ◽  
Satoshi Sasaki

The Japanese Food Guide Spinning Top (JFGST) indicates optimal intake of five food groups (grain, fish and meat, vegetables, milk, and fruits) and sugar and confectionaries. We aimed to investigate whether adherence to the JFGST in 8th grade junior high school students (n = 3162) was associated with cardiometabolic risks and how different scorings of the JFGST influenced the associations. Metabolic risks were assessed from anthropometrics, blood pressure measurements, and blood glucose and lipid profile measurements. Three types of scoring adherent to the JFGST were analyzed (10 points were given for each item with optimal intake; range: 0–60): the original scoring (ORG scoring); first modified scoring, which had no upper limits for vegetables and fruits (MOD1 scoring); and MOD2 scoring without upper limits for five dishes (MOD2 scoring). The MOD2 scoring was positively associated with dietary fiber, potassium, calcium, and vitamins. All types of scorings were associated with low glucose levels (p ≤ 0.001); the MOD2 scoring was associated with low systolic blood pressure (p = 0.001) and low cardiometabolic risk (p = 0.003). Our findings suggest that Japanese adolescents adherent to the JFGST had low cardiometabolic risks and should not fall below lower limits for intake of the abovementioned five food groups.


Lex Russica ◽  
2021 ◽  
pp. 58-65
Author(s):  
A. F. Meshcheryakova

The paper examines some aspects of theoretical views on administrative punishment. The author analyzes the concept of administrative punishment as a measure of responsibility for an administrative offense, its essence and objectives. The study highlights a number of topical problems in the field of legal regulation of the system of administrative punishments that cause difficulties in the correct choice and appointment of administrative punishments. Attention is drawn to the lack of a unified approach for the legislator to establish a system of administrative penalties in terms of their alternative or non-alternative nature. It is shown that some sanctions are incompatible with the nature of the offense; there is a significant gap between the lower and upper limits of penalties in alternative sanctions, a significant difference exists in the sanctions applied to different subjects of the same offense. As a result, the commission of a more socially dangerous act in practice entails infliction of a less severe punishment, which does not meet the goals of prevention. It is noted that in some cases, when deciding on the infliction of an administrative penalty, jurisdictional authorities do not take into account mitigating or aggravating circumstances. Some proposals are made to improve the current legislation on administrative offenses. In particular, the author suggests that it is necessary to correlate all administrative offenses with each other according to the degree of public danger and, on this basis, introduce a system of punishment for administrative offences. It is also proposed to toughen the liability in relation to individuals, since the amount of the fine in relation to individuals and legal entities in some cases differs 50 times. At the same time, the author substantiates the necessity of involving the population in the development of legislative initiatives in this area.


2021 ◽  
Vol 16 (4) ◽  
pp. 273-276
Author(s):  
Bernard F. Lamond ◽  
Luckny Zephyr

Simple estimators were given in (Kachiashvili & Topchishvili, 2016) for the lower and upper limits of an irregular right-angled triangular distribution together with convenient formulas for removing their bias. We argue here that the smallest observation is not a maximum likelihood estimator (MLE) of the lower limit and we present a procedure for computing an MLE of this parameter. We show that the MLE is strictly smaller than the smallest observation and we give some bounds that are useful in a numerical solution procedure. We also present simulation results to assess the bias and variance of the MLE.


Cancers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 6337
Author(s):  
Marco Biolato ◽  
Tiziano Galasso ◽  
Giuseppe Marrone ◽  
Luca Miele ◽  
Antonio Grieco

In Europe and the United States, approximately 1100 and 1800 liver transplantations, respectively, are performed every year for hepatocellular carcinoma (HCC), compared with an annual incidence of 65,000 and 39,000 new cases, respectively. Because of organ shortages, proper patient selection is crucial, especially for those exceeding the Milan criteria. Downstaging is the reduction of the HCC burden to meet the eligibility criteria for liver transplantation. Many techniques can be used in downstaging, including ablation, chemoembolisation, radioembolisation and systemic treatments, with a reported success rate of 60–70%. In recent years, an increasing number of patient responders to downstaging procedures has been included in the waitlist, generally with a comparable five-year post-transplant survival but with a higher probability of dropout than HCC patients within the Milan criteria. While the Milan criteria are generally accepted as the endpoint of downstaging, the upper limits of tumour burden for downstaging HCC for liver transplantation are controversial. Very challenging situations involve HCC patients with large nodules, macrovascular invasion or even extrahepatic metastasis at baseline who respond to increasingly more effective downstaging procedures and who aspire to be placed on the waitlist for transplantation. This narrative review analyses the most important evidence available on cohorts subjected to “extended” downstaging, including HCC patients over the up-to-seven criteria and over the University of California San Francisco downstaging criteria. We also address surrogate markers of biological aggressiveness, such as alpha-fetoprotein and the response stability to locoregional treatments, which are very useful in selecting responders to downstaging procedures for waitlisting inclusion.


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