Intermolecular N-H...O=C hydrogen bonding in the crystal structure of 6-amino-1,3-dimethyluracil

The 6-amino- 1,3-dimethyluracil molecule [6-amino- 1,3- dimethyl-2,4(1H,3H)-pyrimidinedione], C6H9N302 (I), lies on a crystallographic mirror plane and participates in an extensive two-dimensional hydrogen-bonding network in the solid state. Each molecule is involved in N-- H...O=C hydrogen bonding involving the amino and carbonyl gr. oups, with O...N separations of 2.894 (3) and 2.904 (3) A

Extracting the time-dependent transmission rate from infection data via solution of an inverse ODE problem

The transmission rate of many acute infectious diseases varies significantly in time, but the underlying mechanisms are usually uncertain. They may include seasonal changes in the environment, contact rate, immune system response, etc. The transmission rate has been thought difficult to measure directly. We present a new algorithm to compute the time-dependent transmission rate directly from prevalence data, which makes no assumptions about the number of susceptible or vital rates. The algorithm follows our complete and explicit solution of a mathematical inverse problem for SIR-type transmission models. We prove that almost any infection profile can be perfectly fitted by an SIR model with variable transmission rate. This clearly shows a serious danger of overfitting such transmission models. We illustrate the algorithm with historic UK measles data and our observations support the common belief that measles transmission was predominantly driven by school contacts

Intra-individual movement variability during skill transitions: A useful marker?

Applied research suggests athletes and coaches need to be challenged in knowing when and how much a movement should be consciously attended to. This is exacerbated when the skill is in transition between two more stable states, such as when an already well learnt skill is being refined. Using existing theory and research, this paper highlights the potential application of movement variability as a tool to inform a coach’s decision-making process when implementing a systematic approach to technical refinement. Of particular interest is the structure of co-variability between mechanical degrees-of-freedom (e.g., joints) within the movement system’s entirety when undergoing a skill transition. Exemplar data from golf are presented, demonstrating the link between movement variability and mental effort as an important feature of automaticity, and thus intervention design throughout the different stages of refinement. Movement variability was shown to reduce when mental effort directed towards an individual aspect of the skill was high (target variable). The opposite pattern was apparent for variables unrelated to the technical refinement. Therefore, two related indicators, movement variability and mental effort, are offered as a basis through which the evaluation of automaticity during technical refinements may be made

Ideals and finiteness conditions for subsemigroups

In this paper we consider a number of finiteness conditions for semigroups related to their ideal structure, and ask whether such conditions are preserved by sub- or supersemigroups with finite Rees or Green index. Specific properties under consideration include stability, D=J and minimal conditions on ideals.Comment: 25 pages, revised according to referee's comments, to appear in Glasgow Mathematical Journa

Alcohol Consumption and Risk of All-Cause and Cardiovascular Disease Mortality in Men

This study examined the association between consumption of alcoholic beverages and all-cause and cardiovascular disease (CVD) mortality in a cohort of men (n = 31,367). In the Cox proportional hazards model adjusted for age, year of examination, body mass index (BMI), smoking, family history of CVD, and aerobic fitness, there were no significant differences in risk of all-cause mortality across alcohol intake groups. Risk of CVD mortality was reduced 29% in quartile 1 (HR = 0.71, 95% confidence interval (CI): 0.53, 0.95) and 25% in quartile 2 (HR = 0.75, 95% CI: 0.58, 0.98). The amount of alcohol consumed to achieve this risk reduction was <6 drinks/week; less than the amount currently recommended. The addition of other potential confounders and effect modifiers including blood pressure, insulin sensitivity, lipid levels, and psychological variables did not affect the magnitude of association. Future research is needed to validate the current public health recommendations for alcohol consumption

7-Chloro-4-[(E)-(3-chloro­benzyl­idene)hydrazinyl]-1λ4-quinolinium 3-chloro­benzoate

The title salt, C16H12Cl2N3 +·C7H4ClO2 −, features a non-planar cation, the dihedral angle between the quinolinium and benzene residues being 18.98 (10)°. The cation adopts an E conformation about the C—N bond, and the amine group is oriented towards the quinolinium residue. In the crystal, N—H⋯O hydrogen bonds link two cations with two anions, forming a 20-membered {⋯OCO⋯HNC3NH}2 synthon. The dimeric units are connected into a linear supra­molecular chain along [100] via π–π inter­actions [centroid–centroid distance = 3.5625 (13) Å]

The safety of paediatric surgery between COVID-19 surges:an observational study

Despite the ongoing coronavirus disease 2019 (COVID-19) pandemic, elective paediatric surgery must continue safely through the first, second and subsequent waves of disease. This study presents outcome data from a children's hospital in north-west England, the region with the highest prevalence of COVID-19 in England. Children and young people undergoing elective surgery isolated within their household for 14 days, then presented for real-time reverse transcriptase polymerase chain reaction testing for severe acute respiratory syndrome coronavirus disease-2 (SARS-CoV-2) within 72 h of their procedure (or rapid testing within 24 h in high-risk cases), and completed a screening questionnaire on admission. Planned surgery resumed on 26 May 2020; in the four subsequent weeks, there were 197 patients for emergency and 501 for elective procedures. A total of 488 out of 501 (97.4%) elective admissions proceeded, representing a 2.6% COVID-19-related cancellation rate. There was no difference in the incidence of SARS-CoV-2 among children and young people who had or had not isolated for 14 days (p > 0.99). One out of 685 (0.1%) children who had surgery re-presented to the hospital with symptoms potentially consistent with SARS-CoV-2 within 14 days of surgery. Outcomes were similar to those in the same time period in 2019 for length of stay (p = 1.0); unplanned critical care admissions (p = 0.59); and 14-day hospital re-admission (p = 0.17). However, the current cohort were younger (p = 0.037); of increased complexity (

3-[(E)-(7-Chloro-4-quinol­yl)hydrazono­meth­yl]benzonitrile monohydrate

The title monohydrate, C17H11ClN4·H2O, features an essentially planar organic mol­ecule, as seen in the dihedral angle of 2.42 (8)° formed between the quinoline and benzene planes. The conformation about the imine bond is E, and the N—H group is oriented towards the quinoline residue. The major feature of the crystal packing is the formation of supra­molecular chains along [100], whereby the water mol­ecule accepts one N—H⋯O hydrogen bond and makes two O—H⋯N hydrogen bonds. A C—H⋯O link is also present

7-Chloro-4-[(E)-2-(4-methoxy­benzyl­idene)hydrazin-1-yl]quinoline monohydrate

The organic mol­ecule in the title hydrate, C17H14ClN3O·H2O, has a small but significant twist from planarity, as seen in the dihedral angle of 12.10 (17)° between the quinoline and benzene rings. The conformation about the C=N bond is E. Chains along the b axis are formed in the crystal structure aided by water–quinoline O—H⋯N (× 2) and hydrazone–water N—H⋯O hydrogen bonds. Layers of these chains stack along the a axis via C—H⋯π and π–π inter­actions [ring centroid–ring centroid distance = 3.674 (2) Å]. C—H⋯O inter­actions are also present