Charge-Induced Conformational Changes of PEG-(Na<sup>+</sup>)<sub><i>n</i></sub> in a Vacuum and Aqueous Nanodroplets
Bibliographic record
Abstract
Charged-induced conformational changes of sodiated poly(ethylene glycol) (PEG-(Na(+))(n)) in a vacuum and water droplets were studied using molecular simulations. In a vacuum, compact and partially unwound conformations were identified by analyzing occupation probabilities on reaction surfaces defined by the accessible surface area of the macroion, the distance between the centers of mass of the PEG molecule and of the cations and radius of gyration of the macromolecule. The critical charge of the macromolecule for which there is coexistence of various conformations was estimated using the Rayleigh criterion for the breakdown of highly charged droplets and compared with that observed in the simulations. The simulation findings agreed well with the Rayleigh prediction. The properties of sodiated PEG macromolecules in the presence of solvent and ions were also investigated. It was found that the macroion becomes saturated with charge. The highly charged state leads to an extended conformation that is partially expelled by the droplet. However, a portion of the chain is still in contact with the solvent. Drying-out of the solvent leaves the macroion in a stretched necklace-like conformation. The mechanism of release of sodiated PEG from an aqueous droplet was shown to be distinctly different from that of a protonated polyhistidine in a water nanodroplet, demonstrating sensitivity of the disintegration mechanism of the nanodroplet to the degree of hydrophilicity of the macroion.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".