Studies on isolated rat adrenal cells

Research during the past few decades has resulted in detailed knowledge on the production of steroid hormones in the adrenal gland, but the picture is still far from complete. Hardly anything is known about the function of the human fetal adrenal gland which contains a specific fetal zone present only in man and some higher primates. The biochemistry of the inborn errors occurring in adrenal steroidogenesis is also poorly understood. A very intriguing step in the biosynthesis of steroids is the conversion of cholesterol into pregnenolone. This cholesterol side-chain cleaving process is common to the biDsynthetic pathways for all steroid hormones. Furthermore, hormonal regulation of steroid production almost exclusively takes place at this site. The exact mechanism of the sideqhain cleaving process is still uncertain

Study of Z → llγ decays at √s = 8 TeV with the ATLAS detector

This paper presents a study of Z → llγ decays with the ATLAS detector at the Large Hadron Collider. The analysis uses a proton–proton data sample corresponding to an integrated luminosity of 20.2 fb−1 collected at a centre-ofmass energy √s = 8 TeV. Integrated fiducial cross-sections together with normalised differential fiducial cross-sections, sensitive to the kinematics of final-state QED radiation, are obtained. The results are found to be in agreement with stateof-the-art predictions for final-state QED radiation. First measurements of Z → llγ γ decays are also reported

Deep generative models for fast photon shower simulation in ATLAS

The need for large-scale production of highly accurate simulated event samples for the extensive physics programme of the ATLAS experiment at the Large Hadron Collider motivates the development of new simulation techniques. Building on the recent success of deep learning algorithms, variational autoencoders and generative adversarial networks are investigated for modelling the response of the central region of the ATLAS electromagnetic calorimeter to photons of various energies. The properties of synthesised showers are compared with showers from a full detector simulation using geant4. Both variational autoencoders and generative adversarial networks are capable of quickly simulating electromagnetic showers with correct total energies and stochasticity, though the modelling of some shower shape distributions requires more refinement. This feasibility study demonstrates the potential of using such algorithms for ATLAS fast calorimeter simulation in the future and shows a possible way to complement current simulation techniques

Search for doubly charged Higgs boson production in multi-lepton final states using 139 fb−1 of proton–proton collisions at s√ = 13 TeV with the ATLAS detector

A search for pair production of doubly charged Higgs bosons (H±± ), each decaying into a pair of prompt, isolated, and highly energetic leptons with the same electric charge, is presented. The search uses a proton–proton collision data sample at a centre-of-mass energy of 13 TeV corresponding to an integrated luminosity of 139 fb−1 recorded by the ATLAS detector during Run 2 of the Large Hadron Collider (LHC). This analysis focuses on same-charge leptonic decays, H±±→ℓ±ℓ′± where ℓ,ℓ′=e,μ,τ, in two-, three-, and four-lepton channels, but only considers final states which include electrons or muons. No evidence of a signal is observed. Corresponding upper limits on the production cross-section of a doubly charged Higgs boson are derived, as a function of its mass m(H±±), at 95% confidence level. Assuming that the branching ratios to each of the possible leptonic final states are equal, B(H±±→e±e±)=B(H±±→e±μ±)=B(H±±→μ±μ±)=B(H±±→e±τ±)=B(H±±→μ±τ±)=B(H±±→τ±τ±)=1/6, the observed (expected) lower limit on the mass of a doubly charged Higgs boson is 1080 GeV (1065 GeV) within the left-right symmetric type-II seesaw model, which is the strongest limit to date produced by the ATLAS Collaboration. Additionally, this paper provides the first direct test of the Zee–Babu neutrino mass model at the LHC, yielding an observed (expected) lower limit of m(H±±) = 900 GeV (880 GeV)

Search for heavy Majorana or Dirac neutrinos and right-handed W gauge bosons in final states with charged leptons and jets in pp collisions at √s = 13 TeV with the ATLAS detector

A search for heavy right-handed Majorana or Dirac neutrinos NR and heavy right-handed gauge bosons WR is performed in events with energetic electrons or muons, with the same or opposite electric charge, and energetic jets. The search is carried out separately for topologies of clearly separated final-state products (“resolved” channel) and topologies with boosted final states with hadronic and/or leptonic products partially overlapping and reconstructed as a large-radius jet (“boosted” channel). The events are selected from pp collision data at the LHC with an integrated luminosity of 139 fb−1 collected by the ATLAS detector at √s = 13 TeV. No significant deviations from the Standard Model predictions are observed. The results are interpreted within the theoretical framework of a left-right symmetric model, and lower limits are set on masses in the heavy righthanded WR boson and NR plane. The excluded region extends to about m(WR) = 6.4 TeV for both Majorana and Dirac NR neutrinos at m(NR) < 1 TeV. NR with masses of less than 3.5 (3.6) TeV are excluded in the electron (muon) channel at m(WR) = 4.8 TeV for the Majorana neutrinos, and limits of m(NR) up to 3.6 TeV for m(WR) = 5.2 (5.0) TeV in the electron (muon) channel are set for the Dirac neutrinos. These constitute the most stringent exclusion limits to date for the model considered

Software performance of the ATLAS track reconstruction for LHC run 3

Charged particle reconstruction in the presence of many simultaneous proton–proton (pp) collisions in the LHC is a challenging task for the ATLAS experiment’s reconstruction software due to the combinatorial complexity. This paper describes the major changes made to adapt the software to reconstruct high-activity collisions with an average of 50 or more simultaneous pp interactions per bunch crossing (pileup) promptly using the available computing resources. The performance of the key components of the track reconstruction chain and its dependence on pile-up are evaluated, and the improvement achieved compared to the previous software version is quantified. For events with an average of 60 pp collisions per bunch crossing, the updated track reconstruction is twice as fast as the previous version, without significant reduction in reconstruction efficiency and while reducing the rate of combinatorial fake tracks by more than a factor two

Observation of four-top-quark production in the multilepton final state with the ATLAS detector

This paper presents the observation of four-top-quark (tt¯tt¯) production in proton-proton collisions at the LHC. The analysis is performed using an integrated luminosity of 140 fb−1 at a centre-of-mass energy of 13 TeV collected using the ATLAS detector. Events containing two leptons with the same electric charge or at least three leptons (electrons or muons) are selected. Event kinematics are used to separate signal from background through a multivariate discriminant, and dedicated control regions are used to constrain the dominant backgrounds. The observed (expected) significance of the measured tt¯tt¯ signal with respect to the standard model (SM) background-only hypothesis is 6.1 (4.3) standard deviations. The tt¯tt¯ production cross section is measured to be 22.5+6.6−5.5 fb, consistent with the SM prediction of 12.0±2.4 fb within 1.8 standard deviations. Data are also used to set limits on the three-top-quark production cross section, being an irreducible background not measured previously, and to constrain the top-Higgs Yukawa coupling and effective field theory operator coefficients that affect tt¯tt¯ production

Subchronic oral toxicity studies with erythritol in mice and rats

Erythritol is a sugar alcohol (polyol) with potential applications as a low-calorie, bulk sweetener. Ingested erythritol is efficiently absorbed and excreted unchanged via the urine since it is not metabolized systemically by the animal or human body. Erythritol was administered to four groups of 10 male and 10 female Swiss CD-1 mice and four groups of 15 male Wistar Crl:(WI) WU BR rats at dietary levels of 0, 5, 10, or 20% for 90 days. A fifth group of rats received a diet containing 20% erythritol on a time restricted basis (6 hr/day), and a sixth group received a diet containing 20% mannitol for comparison. There were no treatment related mortalities in either mice or rats. Soft stools and occasional diarrhea were observed in rats fed diets with 20% erythritol or mannitol but not in mice. Body weights were slightly yet significantly reduced in rats fed 20% erythritol or mannitol. and in male mice of the 20% dose group. Erythritol intake in the high dose group was approximately 12 g/kg body wt in rats and 44 and 45 g/kg body wt in male and female mice, respectively. Hematological and clinicochemical examinations of blood and plasma did not reveal any treatment related effects. Urine output increased with increasing erythritol dose. In male and female mice of the 20% erythritol group, the creatinine normalized urinary excretion of protein, K-glutamyltransferase (GGT), and electrolytes (Na+, K+, Ca2+, P(i), citrate) was significantly increased while urinary N-acetylglucosaminidase (NAG) remained unchanged. At the 10% level, significantly increased urinary protein (both sexes) and GGT (males only) excretion were seen. In rats, the creatinine-normalized urinary excretion of GGT, NAG, and some electrolytes (Na+, K+, and Ca2+) was increased in some erythritol groups but a clear dose-response relationship was evident only for calcium. On termination of the study, cecal enlargement was seen in rats of the 10 and 20% dose groups and in mice of the 20% dose group. Increased relative and absolute kidney weights were observed in both sexes of mice in the 20% erythritol group, in male mice of the 5 and 10% groups, and in rats of the 10 and 20% erythritol groups. Histopathological examination did not reveal any treatment-related abnormalities in either mice or rats. In conclusion, the ingestion of erythritol for 90 days at dietary levels of up to 20% did not produce signs of toxicity in mice or rats. In particular, the morphological integrity of the kidneys was not adversely affected by the treatment in either species. The increases in urinary excretion of protein, GGT, NAG, and electrolytes were considered to result from extensive osmotic diuresis and a potential overload of the renal excretory system at the high dose levels employed

Consumer and farmer safety evaluation of application of botanical pesticides in black pepper crop protection

This study presents a consumer and farmer safety evaluation on the use of four botanical pesticides in pepper berry crop protection. The pesticides evaluated include preparations from clove, tuba root, sweet flag and pyrethrum. Their safety evaluation was based on their active ingredients being eugenol, rotenone, ß-asarone and pyrethrins, respectively. Botanical pesticides from Acorus calamus are of possible concern because of the genotoxic and carcinogenic ingredient ß-asarone although estimated margins of exposure (MOE) for consumers indicate a low priority for risk management. For the other three botanical pesticides the margin of safety (MOS) between established acute reference doses and/or acceptable daily intake values and intake estimates for the consumer, resulting from their use as a botanical pesticide are not of safety concern, with the exception for levels of rotenone upon use of tuba root extracts on stored berries. Used levels of clove and pyrethrum as botanical pesticides in pepper berry crop production is not of safety concern for consumers or farmers, whereas for use of tuba root and sweet flag some risk factors were defined requiring further evaluation and/or risk management. It seems prudent to look for alternatives for use of sweet flag extracts containing ß-asaron