Tobacco pack display at hospitality venues after the introduction of standardised tobacco packaging in New Zealand: a field observation study.

OBJECTIVES: In March 2018, New Zealand (NZ) introduced standardised tobacco packaging that also featured new pictorial warnings, with implementation completed by early June 2018. We evaluated how the new packaging affected tobacco pack displays in outdoor areas of hospitality venues. DESIGN: Before-and-after descriptive field observation study. SETTING: Central city area of the capital city of NZ (Wellington). PARTICIPANTS: Observations of people smoking and tobacco packs were made at 56 hospitality venues with outdoor tables (2422 separate venue observations), after the introduction of standardised tobacco packaging. Comparisons were made with a prior study in the same setting, from a time when tobacco packaging still featured brand imagery. RESULTS: A total of 8191 patrons, 1113 active smokers and 889 packs and pouches (522 of known orientation) were observed over 2422 venue observations. There were 0.80 visible packs per active smoker in 2018, compared with 1.26 in 2014 (risk ratio (RR)=0.64, 95% CI 0.60 to 0.67, p<0.0001). The new packs in 2018 were also less likely to be displayed face-up, compared with packs in 2014, which had brand imagery on the front face (RR=0.77, 95% CI 0.72 to 0.83, p<0.0001). Pack and pouch display (RR=3.09 in 2014 and 3.10 in 2018) and active smoking (RR=3.16 in 2014 compared with 3.32 in 2018) were higher at venues without children present, compared with venues with children present (this finding was consistent over time). CONCLUSIONS: The reduction in the number of visible packs per active smoker, along with the reduction in face-up positioning of packs, suggests that smokers found the new standardised packs less attractive. Countries introducing standardised packaging should consider evaluating social display of tobacco packaging.

Rotary and linear molecular motors driven by pulses of a chemical fuel.

Many biomolecular motors catalyze the hydrolysis of chemical fuels, such as adenosine triphosphate, and use the energy released to direct motion through information ratchet mechanisms. Here we describe chemically-driven artificial rotary and linear molecular motors that operate through a fundamentally different type of mechanism. The directional rotation of [2]- and [3]catenane rotary molecular motors and the transport of substrates away from equilibrium by a linear molecular pump are induced by acid-base oscillations. The changes simultaneously switch the binding site affinities and the labilities of barriers on the track, creating an energy ratchet. The linear and rotary molecular motors are driven by aliquots of a chemical fuel, trichloroacetic acid. A single fuel pulse generates 360° unidirectional rotation of up to 87% of crown ethers in a [2]catenane rotary motor.

Enantioselective carbohydrate recognition by synthetic lectins in water.

Carbohydrate receptors with a chiral framework have been generated by combining a tetra-aminopyrene and a C3-symmetrical triamine via isophthalamide spacers bearing water-solubilising groups. These "synthetic lectins" are the first to show enantiodiscrimination in aqueous solution, binding N-acetylglucosamine (GlcNAc) with 16 : 1 enantioselectivity. They also show exceptional affinities. GlcNAc is bound with Ka up to 1280 M-1, more than twice that measured for previous synthetic lectins, and three times the value for wheat germ agglutinin, the lectin traditionally employed to bind GlcNAc in glycobiological research. Glucose is bound with Ka = 250 M-1, again higher than previous synthetic lectins. The results suggest that chirality can improve complementarity to carbohydrate substrates and may thus be advantageous in synthetic lectin design.

Artificial molecular motors.

Motor proteins are nature's solution for directing movement at the molecular level. The field of artificial molecular motors takes inspiration from these tiny but powerful machines. Although directional motion on the nanoscale performed by synthetic molecular machines is a relatively new development, significant advances have been made. In this review an overview is given of the principal designs of artificial molecular motors and their modes of operation. Although synthetic molecular motors have also found widespread application as (multistate) switches, we focus on the control of directional movement, both at the molecular scale and at larger magnitudes. We identify some key challenges remaining in the field.

An autonomous chemically fuelled small-molecule motor.

Molecular machines are among the most complex of all functional molecules and lie at the heart of nearly every biological process. A number of synthetic small-molecule machines have been developed, including molecular muscles, synthesizers, pumps, walkers, transporters and light-driven and electrically driven rotary motors. However, although biological molecular motors are powered by chemical gradients or the hydrolysis of adenosine triphosphate (ATP), so far there are no synthetic small-molecule motors that can operate autonomously using chemical energy (that is, the components move with net directionality as long as a chemical fuel is present). Here we describe a system in which a small molecular ring (macrocycle) is continuously transported directionally around a cyclic molecular track when powered by irreversible reactions of a chemical fuel, 9-fluorenylmethoxycarbonyl chloride. Key to the design is that the rate of reaction of this fuel with reactive sites on the cyclic track is faster when the macrocycle is far from the reactive site than when it is near to it. We find that a bulky pyridine-based catalyst promotes carbonate-forming reactions that ratchet the displacement of the macrocycle away from the reactive sites on the track. Under reaction conditions where both attachment and cleavage of the 9-fluorenylmethoxycarbonyl groups occur through different processes, and the cleavage reaction occurs at a rate independent of macrocycle location, net directional rotation of the molecular motor continues for as long as unreacted fuel remains. We anticipate that autonomous chemically fuelled molecular motors will find application as engines in molecular nanotechnology.

Synthetic molecular walkers.

In biological systems, molecular motors have been developed to harness Brownian motion and perform specific tasks. Among the cytoskeletal motor proteins, kinesins ensure directional transport of cargoes to the periphery of the cell by taking discrete steps along microtubular tracks. In the past decade there has been an increasing interest in the development of molecules that mimic aspects of the dynamics of biological systems and can became a starting point for the creation of artificial transport systems.To date, both DNA-based and small-molecule walkers have been developed, each taking advantage of the different chemistries available to them. DNA strollers exploit orthogonal base pairing and utilize strand-displacement reactions to control the relative association of the component parts. Small-molecule walkers take advantage of the reversibility of weak noncovalent interactions as well as the robustness of dynamic covalent bonds in order to transport molecular fragments along surfaces and molecular tracks using both diffusional processes and ratchet mechanisms. Here we review both types of synthetic systems, including their designs, dynamics, and how they are being used to perform functions by controlled mechanical motion at the molecular level.

Testicular microlithiasis in patients with Down syndrome.

OBJECTIVES: Testicular microlithiasis (TM) occurs with benign as well as with pathological conditions, such as testicular cancer. Since Down syndrome (DS) may be associated with increased frequency of testicular cancer, we determined the prevalence of TM in DS in patients from a DS clinic and evaluated the prevalence by age group. STUDY DESIGN: We compared results of research scrotal ultrasounds obtained from 1998 to 2001 from 92 Latino patients with DS (ages newborn to 29.7 years) and clinical ultrasounds obtained from 1998 to 2004 from 200 Latino patients without DS (ages newborn to 18.3 years). We also reviewed the medical records. RESULTS: The prevalence of TM in DS was 29%, significantly higher than the 7% found in patients without DS (P < .0001). Twenty of the 27 patients with DS and TM had no testicular pathology clinically or by history. The TM prevalence in the entire group of patients with and without DS increased with advancing age. CONCLUSIONS: We found a significantly increased prevalence of TM in DS. The clinical significance of TM needs to be investigated further.