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The motions of Newton's cradle, consisting of several steel balls hanging side-by-side, have been analysed in terms of a sound pulse that travels via points of contact among the balls. This presupposes a focused energy beam. When the pulse reaches the fifth and final ball, the energy disperses and dislocates the ball with a trajectory equivalent to that of the first ball after it was released. The pulse passes unchanged through the internal balls without, therefore, causing movement of these balls. Lack of movement can be affirmed by immobilising one or more of the balls, thereby disproving both the gap and vibrating lattice models. This also contrasts with previous mechanisms that postulate complete energy dispersal within a ball prior to transferring the energy to another ball. Inserting an inelastic barrier between the second and third balls disrupts the pulse such that it spreads out to reach regions that are not in contact with another ball. As a result, the normally stationary third ball is forced into a forward motion, thereby pushing the fourth and fifth ball with it as a single unit. The model is valuable in explaining a fact that has puzzled physicists for generations: why is only one motional mode observed among a multitude of motions that maintain a constant momentum and kinetic energy as required by the laws of physics? The answer lies in the fact that all motions, except the one that is actually observed, require a rebound in one or more of the balls. Since the energy beam formed upon impact is unidirectional, reverse motions are not accommodated.

Preassembly refers to an evolutionary mechanism that complements current theory. It proposes that genes and gene fragments, formed over the eons among libraries of noncoding genes, ultimately contributed to coding sequences. Previous publications of ours on preassembly have helped explain many enigmas that beset modern biology; for example, the Cambrian explosion ("one of the most remarkable and puzzling events in the history of life," S. J. Gould), and the appearance of flowering plants with their sparsity of precursors (an "abominable mystery," C. R. Darwin). The rapid evolutionary development of the domestic cat and human intelligence is also viewed as evidence for a mechanism supplementing neo-Darwinism. The current account centers on convergent evolution as interpreted via DNA preassembly. Convergent evolution refers to the development of near-identical traits in organisms that lack a common ancestor. A prime example is the remarkable similarity between the eyes of humans and octopuses. When early ancestors of these species split apart on the evolution tree, hundreds of millions of years ago, only eyespots existed. Clearly, convergent eyes in the two organisms evolved independently. Current evolutionary belief says that the eyes appeared after Nature had first screened hundreds of mutations, one at a time, and that this multistep and random process produced, fortuitously, two near identical structures. Preassembly, on the other hand, proposes primeval genes, or DNA segments, that had been collected over vast time periods within huge libraries of noncoding DNA (i.e., "preassembled genes"). Ultimately, these DNA units were incorporated into functional genes, a process possibly aided by genetic site-scanning. Menger, F. M. (2017). Molecular Lamarckism. On the evolution of human intelligence. World Futures, 73, 89–103. Menger, F. M. (2020). An alternative view of evolution, how DNA was altered over geological time. Molecules, 25, 5081. Menger, F. M., & Rizvi, S. A. A. (2021). Evolution of complexity. Molecular aspects of preassembly. Molecules, 26, 6618. [ABSTRACT FROM AUTHOR]

This article describes a short synthesis and many of the difficulties experienced while carrying it out (e.g., low yields, impurities, racemization, nonrepeatable literature preps, etc.). As such, students will be educated in aspects of synthetic organic chemistry that are often down-played, or even not mentioned, in published syntheses. (Contains 1 figure and 10 schemes.)

The way the colloidal properties of surfactants respond to insertion of non-hydrocarbon functionalities within chains that are normally entirely hydrocarbon is described. On examination of monomolecular films of 10-hydroxysteraric acid, it was found that the hydroxyl and polar headgroup maintain contact with an aqueous subphase while the intervening chains form 'loops' above it.

Asterisks that comprise of six semigrid arms projecting from a benzene nucleus are synthesized with one, two, or three aromatic rings (connected by sulfur atoms) in each of the six arms. A phosphomonoester at the termini of each arm solubilized the asterisks in water.

The article discusses the synthesis of the multiarmed and multicationic gemini surfactants that have pentaerythritol, dipentaerythritol and adamantane cores. Colloidal properties of the gemini in water have been examined.

A study was conducted to characterize the synthesis and reactivity of the 5-fluorouracil/cytarabine mutual anti-cancer drugs. The rate constants for hydrolysis of ester in 10 and in 1a was analyzed at various pH values. A mutual prodrug analog was also determined with aniline replacing the ara-C unit. Results indicated that the anticancer drugs can be released by enzymatic hydrolysis. Findings also showed that the prodrugs support two labile groups linking the drugs to the spacer.

Research was conducted to examine chelated lithium phenolates using NMR and X-ray spectrometry. Lithium phenolates with carbonyl functionalities in both the 2 and 6 positions enabled the metal to chelate to two oxygens. It was also observed through dynamic NMR that lithium has the ability to oscillate between the two chelating sites. Results indicate that lithium is static toward oscillation and that lithium phenolates form dimeric or tetrameric aggregates having a trigonal or a tetrahedral metal geometry.

The approaches for the synthesis of defective phospholipids is discussed. The methods either involve termination of the short fatty acid ends of the phospholipids, displacement of the bromine group with methoxide, acylation of the carboxylic acids, or insertion of the phosphatidylcholine group at the very end of the sequences of the complete dimeric skeleton. The schemes for the preparation of eight new phospholipids are presented.

Anionic liposomes are adsorbed onto the surface of spherical polymer particles bearing grafted linear cationic macromolecules. The size, shape, and encapsulation ability of the liposomes have remained unchanged upon adsorption, which have provided immobilized self-organizing containers that have potential applications in the biomedical field.

Efforts to correct errors in a published scientific article were met with defensive evasion on the part of editors and constituted a failure of the peer-review system. Senior editor Allen J. Bard and associate editor Richard L. Schowen of the Journal of the American Chemical Society dismissed efforts to point out egregious errors in a pair of articles co-authored by Ronald Breslow. The interests of science and of the public which funds it require that editors permit rebuttals by those who have the time and interest to read an article carefully.

A study was conducted to re-evaluate the molecular areas of soluble films at the air/water interface derived by the Gibbs equation which are too large to account for the abrupt surface tension decline. The surface tension plot leveled off due to saturation proved that the interface in the Gibbs region is not saturated and hundreds of published molecular areas obtained by the Gibbs approach should be reconsidered.

Conductivity and diffusion NMR are used to measure the critical micelle concentration (CMC) values from dodecyltrimethylammonium bromide (DTAB)/trianion mixtures and gain insigth into the sharp break observed in surface-tension 'CMC plots'. The unusual discrepancy observed between the CMC based on surface tension and on the two 'bulk' methods are attributed to saturation of the air/water interface by a DTAB/trianion complex far below the concentration at which the micelles form.

The preparation and studies of a series of polybetaines ([PB.sub.n]) having cationic and anionic units covalently linked by short -[(C[H.sub.2]).sub.n]- spacer is reported. The results revealed that the length of the -[(C[H.sub.2]).sub.n]- spacer in betaine units have a significant effect on the ability of polybetaines to interact with anionic liposomes and to induce structural rearrangement within the liposomal membrane.

The studies of the amphiphile diketopiperazine ring inserted between a chain and an ionic headgroup is reported. The results from the characterization of properties of ionic headgroup provide insight into monolayer films at the air/water interface where the diketopiperazine have a profound effect on the compression isotherms.

Solution and solid-phase synthesis of a cyanine dye conjugated to polystyrene beads are described. The spectroscopic properties of conjugated dye exposed to apolar media where ion pairing and reduced delocalization is possible are examined.

The NMR diffusometry and other techniques are employed to study the aggregation and hydration of short-chain nonionic surfactants containing amide bonds. The presence of the amide bonds in the surfactants is shown to lead to higher surface hydration in the compounds.

The self-assembly of penta-segmentation organic molecules of the general structure A-B-A-B-A or B-A-B-A-B, where A is a hydrophilic polyether and B is a hydrophobic carbon chain, is examined. The results have shown that the segmentation can have a dramatic effect upon solute properties, including solubility, propensity to self-assemble, aggregation number, and cooperativity.

[super 23]Na NMR evidence is provided showing that sodium ions can locate itself inside the actual phospholipid bilayer. A vesicular membrane composed of a conventional phospholipid (1-palmitoyl-2-oleoyl phosphatidylcholine or POPC) admixed with a lesser amount of a 'designer' phospholipid that possesses ester groups along its normally all-hydrocarbon chains is used to show that the ester groups create membrane 'pockets' in which sodium ions reside.

A kinetic approach is described to investigate chain exposure of self-assembly interiors to external elements, in which hydration or chain/water contact is a key feature. A methylene in a hydrophobic thio-surfactant chain is replaced by a sulfur atom, and NMR resolutions are used to study the oxidation rates of the sulfur labels that can be used to assess chain exposure to the external medium in self-assemblies and polymeric systems.

A study on ice formation from saline at concentrations near that of seawater, by cryo-etch high-resolution scanning electron microscopy, is presented. The study reveals some surprising morphologies.

Study of 10 asymmetric gemini surfactants that self-assemble into vesicles, which, in turn, self-assemble into gels is presented. The strings of vesicles create a complex network that rigidifies the water.

It is found that giant vesicles lend themselves to quantitative analysis by the parallax method. Despite the effect of a high radius of curvature upon chain disorder, small vesicles are found to be identical.

A remarkable parallel between jointing in geological formations and jointing in vitreous ice containing a surfactant when observed by cryo- high resolution scanning electron microscopy (cryo- HRSEM) is described. The method can be particularly useful and non invasive for discovering new modes of self assembly in water.