19 research outputs found
Unnatural Origin of Fermion Masses for Technicolor
We explore the scenario in which the breaking of the electroweak symmetry is
due to the simultaneous presence and interplay of a dynamical sector and an
unnatural elementary Higgs. We introduce a low energy effective Lagrangian and
constrain the various couplings via direct search limits and electroweak and
flavor precision tests. We find that the model we study is a viable model of
dynamical breaking of the electroweak symmetry.Comment: 20 pages, 7 eps figure
Changing trends in mortality among solid organ transplant recipients hospitalized for COVID-19 during the course of the pandemic
Mortality among patients hospitalized for COVID-19 has declined over the course of the pandemic. Mortality trends specifically in solid organ transplant recipients (SOTR) are unknown. Using data from a multicenter registry of SOTR hospitalized for COVID-19, we compared 28-day mortality between early 2020 (March 1, 2020–June 19, 2020) and late 2020 (June 20, 2020–December 31, 2020). Multivariable logistic regression was used to assess comorbidity-adjusted mortality. Time period of diagnosis was available for 1435/1616 (88.8%) SOTR and 971/1435 (67.7%) were hospitalized: 571/753 (75.8%) in early 2020 and 402/682 (58.9%) in late 2020 (p <.001). Crude 28-day mortality decreased between the early and late periods (112/571 [19.6%] vs. 55/402 [13.7%]) and remained lower in the late period even after adjusting for baseline comorbidities (aOR 0.67, 95% CI 0.46–0.98, p =.016). Between the early and late periods, the use of corticosteroids (≥6 mg dexamethasone/day) and remdesivir increased (62/571 [10.9%] vs. 243/402 [61.5%], p <.001 and 50/571 [8.8%] vs. 213/402 [52.2%], p <.001, respectively), and the use of hydroxychloroquine and IL-6/IL-6 receptor inhibitor decreased (329/571 [60.0%] vs. 4/492 [1.0%], p <.001 and 73/571 [12.8%] vs. 5/402 [1.2%], p <.001, respectively). Mortality among SOTR hospitalized for COVID-19 declined between early and late 2020, consistent with trends reported in the general population. The mechanism(s) underlying improved survival require further study
COVID-19 in hospitalized lung and non-lung solid organ transplant recipients: A comparative analysis from a multicenter study
Lung transplant recipients (LTR) with coronavirus disease 2019 (COVID-19) may have higher mortality than non-lung solid organ transplant recipients (SOTR), but direct comparisons are limited. Risk factors for mortality specifically in LTR have not been explored. We performed a multicenter cohort study of adult SOTR with COVID-19 to compare mortality by 28 days between hospitalized LTR and non-lung SOTR. Multivariable logistic regression models were used to assess comorbidity-adjusted mortality among LTR vs. non-lung SOTR and to determine risk factors for death in LTR. Of 1,616 SOTR with COVID-19, 1,081 (66%) were hospitalized including 120/159 (75%) LTR and 961/1457 (66%) non-lung SOTR (p =.02). Mortality was higher among LTR compared to non-lung SOTR (24% vs. 16%, respectively, p =.032), and lung transplant was independently associated with death after adjusting for age and comorbidities (aOR 1.7, 95% CI 1.0–2.6, p =.04). Among LTR, chronic lung allograft dysfunction (aOR 3.3, 95% CI 1.0–11.3, p =.05) was the only independent risk factor for mortality and age >65 years, heart failure and obesity were not independently associated with death. Among SOTR hospitalized for COVID-19, LTR had higher mortality than non-lung SOTR. In LTR, chronic allograft dysfunction was independently associated with mortality
The complex relationship between CD4 count, HIV viral load, trimethoprim-sulfamethoxazole prophylaxis, and skin-and-soft-tissue infection risk in patients with HIV: insights from a causal diagram and simulation study
A chalcone showing positional disorder, two related diarylcyclohexenones showing enantiomeric disorder and a related hydroxyterphenyl, all derived from simple carbonyl precursors
Four compounds are reported, all of which lie along a versatile reaction pathway which leads from simple carbonyl compounds to terphenyls. (2E)-1-(2,4- Dichlorophenyl)-3-[4-(prop-1-en-2-yl)phenyl]prop-2-en-1-one, C18H14Cl2O, (I), prepared from 4-(prop-1-en-2-yl)benzaldehyde and 2,4-dichloroacetophenone, exhibits disorder over two sets of atomic sites having occupancies of 0.664 (6) and 0.336 (6). The related chalcone (2E)-3-(4-chlorophenyl)-1-(4-fluorophenyl)-prop-2-en-1-one reacts with acetone to produce (5RS)-3-(4-chlorophenyl)-5-[4-(propan-2-yl)phenyl]cyclohex-2-en-1-one, C21H21ClO, (II), which exhibits enantiomeric disorder with occupancies at the reference site of 0.662 (4) and 0.338 (4) for the (5R) and (5S) forms; the same chalcone reacts with methyl 3-oxobutanoate to give methyl (1RS, 6SR)-4-(4-chlorophenyl)-6-[4-(propan-2-yl)phenyl]-2-oxocyclohex-3-ene-1-carboxylate, C23H23ClO3, (III), where the reference site contains both (1R,6S) and (1S,6R) forms with occupancies of 0.923 (3) and 0.077 (3), respectively. Oxidation, using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, of ethyl (1RS, 6SR)-6-(4-bromophenyl)-4-(4-fluorophenyl)-2-oxocyclohex-3-ene-1-carboxylate, prepared in a similar manner to (II) and (III), produces ethyl 4 ''-bromo-4-fluoro-5'-hydroxy-1,1':3',1 ''-terphenyl-4'-carboxylate, C21H16BrFO3, (IV), which crystallizes with Z' = 2 in the space group P (1) over bar. There are no significant intermolecular interactions in the structures of compounds (I) and (II), but for the major disorder component of compound (III), the molecules are linked into sheets by a combination of C-H center dot center dot center dot O and C-H center dot center dot center dot pi(arene) hydrogen bonds. The two independent molecules of compound (IV) form two different centrosymmetric dimers, one built from inversion-related pairs of C-H center dot center dot center dot O hydrogen bonds and the other from inversion-related pairs of C-H center dot center dot center dot pi(arene) hydrogen bonds. Comparisons are made with related compounds.</p
Crystal structures of five (2-chloro-quinolin-3-yl)methyl ethers : supra-molecular assembly in one and two dimensions mediated by hydrogen bonding and π-π stacking
In the molecules of the title compounds, methyl 5-bromo-2-[(2-chloroquinolin-3-yl)methoxy]benzoate, C18H13BrClNO3, (I), methyl 5-bromo-2-[(2-chloro-6-methylquinolin-3-yl)methoxy]benzoate, C19H15BrClNO3, (II), methyl 2-[(2-chloro-6-methylquinolin-3-yl)methoxy]benzoate, C19H16ClNO3, (III), which crystallizes with Z' = 4 in space group P212121, and 2-chloro-3-[(naphthalen-1-yloxy)methyl]quinoline, C20H14ClNO, (IV), the non-H atoms are nearly coplanar, but in {5-[(2-chloroquinolin-3-yl)methoxy]-4-(hydroxymethyl)-6-methylpyridin-3-yl}methanol, C18H17ClN2O3, (V), the planes of the quinoline unit and of the unfused pyridine ring are almost parallel, although not coplanar. The molecules of (I) are linked by two independent [pi]-[pi] stacking interactions to form chains, but there are no hydrogen bonds present in the structure. In (II), the molecules are weakly linked into chains by a single type of [pi]-[pi] stacking interaction. In (III), three of the four independent molecules are linked by [pi]-[pi] stacking interactions but the other molecule does not participate in such interactions. Weak C-H...O hydrogen bonds link the molecules into three types of chains, two of which contain just one type of independent molecule while the third type of chain contains two types of molecule. The molecules of (IV) are linked into chains by a C-H...π(arene) hydrogen bond, but [pi]-[pi] stacking interactions are absent. In (V), there is an intramolecular O-H...O hydrogen bond, and molecules are linked into sheets by a combination of O-H...N hydrogen bonds and π-π stacking interactions.Publisher PDFPeer reviewe