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Record W3186991173

Biochemistry, Tear Film

2021· article· en· W3186991173 on OpenAlexaff
Angela Y. Chang, Boonkit Purt

Bibliographic record

VenueStatPearls · 2021
Typearticle
Languageen
FieldMedicine
TopicOcular Surface and Contact Lens
Canadian institutionsColumbia College
Fundersnot available
KeywordsTearsConjunctivaCorneaOphthalmologyAnatomyReflexLactoferrinChemistryMedicineSurgeryPathologyInternal medicineBiochemistry
DOInot available

Abstract

fetched live from OpenAlex

The tear film covers the ocular surface and is essential for protecting the eye from the environment, lubricating the ocular surface, maintaining a smooth surface for light refraction, and preserving the health of the conjunctiva and the avascular cornea. The tear film is approximately 3 to 10 μL in volume, 3 μm thick, and secreted at a rate of 1 to 2 μL/min. The pH of tears is approximately 7.45 and ranges between 7.14 to 7.82, depending on diurnal and seasonal influences. Prolonged lid closure, such as during sleep, leads to a buildup of carbon dioxide, thus lowering the pH. It can conceptually be thought of as having three major layers – inner mucin, middle aqueous, and outer lipid layer. The main lacrimal glands produce most of the aqueous tear layer, with small amounts produced by the goblet cells in the conjunctiva and accessory lacrimal glands. The tears then evaporate or are drained through the lacrimal puncta.There are three different types of tears, each with unique biochemistries. Basal tears are typically present on the ocular surface, providing nutrients to the ocular surface, maintaining ocular comfort, and ridding the surface of debris. Reflex tears are those released in response to irritants, including chemicals and foreign bodies. Reflex tears are produced in higher quantities than basal tears and are involved in flushing the ocular surface of irritants. Closed eye tears are those lubricating the eyes during sleep. Some components of the tear film, such as lactoferrin, lipocalin-1, and lysozyme, remain relatively constant between different types of tears. However, the total amount of protein, lipid, and secretory IgA varies between types; protein and lipid content is highest in basal tears. Despite differences in composition, the osmolarities in tear types remain relatively constant.

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 machine prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.

metaresearch head score (Codex)0.002
metaresearch head score (Gemma)0.006
Version: metacan-v3-hybrid-931329e0061cValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Not applicable · Consensus signal: none
GenreCandidate signal: Other · Consensus signal: none
Teacher disagreement score0.021
Threshold uncertainty score0.071

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0020.006
Meta-epidemiology (narrow)0.0020.001
Meta-epidemiology (broad)0.0020.001
Bibliometrics0.0060.004
Science and technology studies0.0010.002
Scholarly communication0.0050.003
Open science0.0020.002
Research integrity0.0020.003
Insufficient payload (model declined to judge)0.0210.025

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.

Opus teacher head0.010
GPT teacher head0.261
Teacher spread0.251 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designNot applicable
Domainnot available
GenreOther

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".

Quick stats

Citations12
Published2021
Admission routes1
Has abstractyes

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