Initial Imaging of Pregnant Patients in the Trauma Bay-Discussion and Review of Presentations at a Level-1 Trauma Centre.

Trauma is the leading non-obstetric cause of maternal and fetal mortality and affects an estimated 5-7% of all pregnancies. Pregnant women, thankfully, are a small subset of patients presenting in the trauma bay, but they do have distinctive physiologic and anatomic changes. These increase the risk of certain traumatic injuries, and the gravid uterus can both be the primary site of injury and mask other injuries. The primary focus of the initial management of the pregnant trauma patient should be that of maternal stabilization and treatment since it directly affects the fetal outcome. Diagnostic imaging plays a pivotal role in initial traumatic injury assessment and should not deviate from normal routine in the pregnant patient. Radiographs and focused assessment with sonography in the trauma bay will direct the use of contrast-enhanced computed tomography (CT), which remains the cornerstone to evaluate the potential presence of further management-altering injuries. A thorough understanding of its risks and benefits is paramount, especially in the pregnant patient. However, like any other trauma patient, if evaluation for injury with CT is indicated, it should not be denied to a pregnant trauma patient due to fear of radiation exposure.

Periodic Borromean rings, rods and chains.

This article describes periodic polycatenane structures built from interlocked rings in which no two are directly linked. The 2-periodic vertex-, edge- and ring-transitive families of hexagonal Borromean rings are described in detail, and it is shown how these give rise to 1- and 3-periodic ring-transitive (isonemal) families. A second isonemal 2-periodic family is identified, as is a unique 3-periodic Borromean assembly of equilateral triangles. Also reported is a notable 2-periodic structure comprising chains of linked rings in which the chains are locked in place but no two chains are directly interlinked, being held in place as a novel `quasi-Borromean' set of four repeating components.

Isogonal 2-periodic polycatenanes: chain mail.

For 2-periodic polycatenanes with isogonal (vertex-transitive) embeddings, the basic units linked are torus knots and links including the unknots (untangled polygons). Twenty-four infinite families have been identified, with hexagonal, tetragonal or rectangular symmetry. The simplest members of each family are described and illustrated. A method for determining the catenation number of a ring based on electromagnetic theory is described.

Periodic diffraction from an aperiodic monohedral tiling.

The diffraction pattern from the recently reported aperiodic `einstein', or `hat', monohedral tiling [Smith et al. (2023). arXiv:2303.10798v1] has been analyzed. The structure is the hexagonal mta net, a kite tiling, with aperiodic vertex deletions. A large model's diffraction pattern displays a robust sixfold periodicity in plane group p6. A repeating, roughly triangular motif of `diffused intensity' arises between the strongest Bragg peaks. The motif contains high-density regions of discrete `satellite' peaks, rather than continuous `diffuse scattering', breaking mirror symmetry, consistent with the chiral hat tiling.

Isogonal embeddings of interwoven and self-entangled honeycomb (hcb) nets and related interpenetrating primitive cubic (pcu) nets.

Two- and three-periodic vertex-transitive (isogonal) piecewise-linear embeddings of self-entangled and interwoven honeycomb nets are described. The infinite families with trigonal symmetry and edge transitivity (isotoxal) are particularly interesting as they have the Borromean property that no two nets are directly linked. These also lead directly to infinite families of interpenetrating primitive cubic nets (pcu) that are also vertex- and edge-transitive and have embeddings with 90° angles between edges.

Three-periodic nets, tilings and surfaces. A short review and new results.

A brief introductory review is provided of the theory of tilings of 3-periodic nets and related periodic surfaces. Tilings have a transitivity [p q r s] indicating the vertex, edge, face and tile transitivity. Proper, natural and minimal-transitivity tilings of nets are described. Essential rings are used for finding the minimal-transitivity tiling for a given net. Tiling theory is used to find all edge- and face-transitive tilings (q = r = 1) and to find seven, one, one and 12 examples of tilings with transitivity [1 1 1 1], [1 1 1 2], [2 1 1 1] and [2 1 1 2], respectively. These are all minimal-transitivity tilings. This work identifies the 3-periodic surfaces defined by the nets of the tiling and its dual and indicates how 3-periodic nets arise from tilings of those surfaces.

Borromean rings redux. A missing link found - a Borromean triplet of Borromean triplets.

This paper describes a nine-component Borromean structure - a Borromean triplet of Borromean triplets - that was missing from an earlier enumeration.

Piecewise-linear embeddings of decussate extended θ graphs and tetrahedra.

An nθ graph is an n-valent graph with two vertices. From symmetry considerations, it has vertex-edge transitivity 1 1. Here, they are considered extended with divalent vertices added to the edges to explore the simplest piecewise-linear tangled embeddings with straight, non-intersecting edges (sticks). The simplest tangles found are those with 3n sticks, transitivity 2 2, and with 2⌊(n - 1)/2⌋ ambient-anisotopic tangles. The simplest finite and 1-, 2- and 3-periodic decussate structures (links and tangles) are described. These include finite cubic and icosahedral and 1- and 3-periodic links, all with minimal transitivity. The paper also presents the simplest tangles of extended tetrahedra and their linkages to form periodic polycatenanes. A vertex- and edge-transitive embedding of a tangled srs net with tangled and polycatenated θ graphs and vertex-transitive tangled diamond (dia) nets are described.

Omega-3 fatty acids in the management of dry eye disease-An updated systematic review and meta-analysis.

PURPOSE: The purpose of this study was to examine the effectiveness of omega-3 fatty acids in comparison to a placebo in the management of dry eye disease. METHODS: A systematic literature search was performed including randomised controlled trials (RCTs) comparing omega-3 versus placebo in the management of dry eye disease in human subjects. There were no language or time restrictions. Eligible trials were assessed for bias and assigned a risk-of-bias score. Data extraction was carried out using a standardised data extraction form, and meta-analysis was performed using a random effects model for continuous data. The outcome measures were Ocular Surface Disease Index (OSDI) scores, tear breakup time (TBUT) measurements, corneal staining and Schirmer's score. Statistical heterogeneity was defined as substantial if the I2 test achieved a value >60%. RESULTS: Eight parallel RCTs including 1107 subjects met eligibility criteria. None of the included studies achieved low risk of bias. Data synthesis demonstrated an improvement in the mean change in OSDI score from baseline to final assessment. Omega-3 supplementation conferred no evident improvement in corneal staining, TBUT or Schirmer's score. There was considerable statistical heterogeneity in all four outcome measures. CONCLUSIONS: This updated systematic review and meta-analysis indicates that omega-3 supplementation improves subjective symptoms in patients with dry eye disease.

Isogonal piecewise-linear embeddings of 1-periodic knots and links, and related 2-periodic chain-link and knitting patterns.

Families of 1- and 2-periodic knots and weavings that have isogonal (vertex-transitive) piecewise-linear embeddings are described. In these structures there is just one thread, or multiple threads with parallel or collinear axes. The principal structures are a large family of 1-periodic knots and related multi-thread infinite links, knitting patterns and chain-link weaving. The relevance to synthetic chemistry is described in terms of targets for designed synthesis such as mechanically interlocked polymers.

Tangled piecewise-linear embeddings of trivalent graphs.

A method is described for generating and exploring tangled piecewise-linear embeddings of trivalent graphs under the constraints of point-group symmetry. It is shown that the possible vertex-transitive tangles are either graphs of vertex-transitive polyhedra or bipartite vertex-transitive nonplanar graphs. One tangle is found for 6 vertices, three for 8 vertices (tangled cubes), seven for 10 vertices, and 21 for 12 vertices. Also described are four isogonal embeddings of pairs of cubes and 12 triplets of tangled cubes (16 and 24 vertices, respectively). Vertex 2-transitive embeddings are obtained for tangled trivalent graphs with 6 vertices (two found) and 8 vertices (45 found). Symmetrical tangles of the 10-vertex Petersen graph and the 20-vertex Desargues graph are also described. Extensions to periodic tangles are indicated. These are all interesting and viable targets for molecular synthesis.

Presence of nitrofurans and their metabolites in gelatine.

Following the detection of semicarbazide (SEM) in gelatine by Italian Authorities, at levels exceeding by three times the reference point for action (RPA) of 1 µg/kg, set out by Commission Regulation (EU) 2019/1871 for nitrofurans and their metabolites, the European Commission mandated EFSA to investigate the available sources of nitrofurans and their metabolites in gelatine. European Commission also asked EFSA to provide approaches that would distinguish SEM occurring due to illegal treatment with nitrofurazone from SEM produced during food processing. The literature indicates that SEM, both free and bound to macromolecules, could occur also in food products such as gelatine, during food processing, arising from the use of disinfecting agents and/or from reactions of various food components and, therefore, SEM cannot be considered as an unequivocal marker of the abuse of nitrofurazone in animal production. It is recommended to investigate in more detail which processing conditions lead to the formation of SEM in gelatine during its production and what levels can be found. One potential approach to distinguishing between SEM from nitrofurazone and SEM from other sources in food products, such as gelatine, might be based on determining the ratio of bound:free SEM in a sample of gelatine. However, whether the ratio of bound:free SEM would unequivocally distinguish between SEM arising from nitrofurazone abuse or from other sources still needs to be demonstrated.

On Borromean links and related structures.

The creation of knotted, woven and linked molecular structures is an exciting and growing field in synthetic chemistry. Presented here is a description of an extended family of structures related to the classical `Borromean rings', in which no two rings are directly linked. These structures may serve as templates for the designed synthesis of Borromean polycatenanes. Links of n components in which no two are directly linked are termed `n-Borromean' [Liang & Mislow (1994). J. Math. Chem. 16, 27-35]. In the classic Borromean rings the components are three rings (closed loops). More generally, they may be a finite number of periodic objects such as graphs (nets), or sets of strings related by translations as in periodic chain mail. It has been shown [Chamberland & Herman (2015). Math. Intelligencer, 37, 20-25] that the linking patterns can be described by complete directed graphs (known as tournaments) and those up to 13 vertices that are vertex-transitive are enumerated. In turn, these lead to ring-transitive (isonemal) n-Borromean rings. Optimal piecewise-linear embeddings of such structures are given in their highest-symmetry point groups. In particular, isonemal embeddings with rotoinversion symmetry are described for three, five, six, seven, nine, ten, 11, 13 and 14 rings. Piecewise-linear embeddings are also given of isonemal 1- and 2-periodic polycatenanes (chains and chain mail) in their highest-symmetry setting. Also the linking of n-Borromean sets of interleaved honeycomb nets is described.

Piecewise-linear embeddings of knots and links with rotoinversion symmetry.

This article describes the simplest members of an infinite family of knots and links that have achiral piecewise-linear embeddings in which linear segments (sticks) meet at corners. The structures described are all corner- and stick-2-transitive - the smallest possible for achiral knots.

Evolution of 14-Connected Zr6 Secondary Building Units through Postsynthetic Linker Incorporation.

Two new zirconium MOFs, WSU-6 and WSU-7, were synthesized through postsynthetic modifications. In both cases, linker insertion was conducted on a MOF consisting of eight-connected (8-c) Zr6 cluster and four-connected (4-c) ETTC linker, WSU-5, which possesses the uncommon 4, 8-c scu-c topology. The insertion of 1, 4-benzenedicarboxylate into the MOF formed the new 4, 12-c mjh topology, WSU-6. Interestingly, when 2, 6-naphthalenedicarboxylate was inserted, WSU-7 can be formed, which possesses a new 4, 14-c jkz topology. WSU-7 contains very rare 14-c Zr6 secondary building units (SBUs) and is the first MOF to have a Zr6 SBUs with connectivity greater than 12. The three Zr-MOFs were structurally characterized, and the photoluminescence properties of the materials were also studied.

Cavity-enhanced microwave readout of a solid-state spin sensor.

Overcoming poor readout is an increasingly urgent challenge for devices based on solid-state spin defects, particularly given their rapid adoption in quantum sensing, quantum information, and tests of fundamental physics. However, in spite of experimental progress in specific systems, solid-state spin sensors still lack a universal, high-fidelity readout technique. Here we demonstrate high-fidelity, room-temperature readout of an ensemble of nitrogen-vacancy centers via strong coupling to a dielectric microwave cavity, building on similar techniques commonly applied in cryogenic circuit cavity quantum electrodynamics. This strong collective interaction allows the spin ensemble's microwave transition to be probed directly, thereby overcoming the optical photon shot noise limitations of conventional fluorescence readout. Applying this technique to magnetometry, we show magnetic sensitivity approaching the Johnson-Nyquist noise limit of the system. Our results pave a clear path to achieve unity readout fidelity of solid-state spin sensors through increased ensemble size, reduced spin-resonance linewidth, or improved cavity quality factor.

Isogonal piecewise linear embeddings of 1-periodic weaves and some related structures.

Crystallographic descriptions of isogonal piecewise linear embeddings of 1-periodic weaves and links (chains) are presented. These are composed of straight segments (sticks) that meet at corners (2-valent vertices). Descriptions are also given of some plaits - woven periodic bands, three simple periodic knots and isogonal interwoven rods.

Overnight attending radiologist coverage decreases imaging-related emergency department recalls by at least 90.

PURPOSE: Benefits of overnight attending radiologist final reports are debated, often stating low resident discrepancy rates, usually assessed retrospectively. The objective of this study was to assess the impact of overnight final reporting on the recall rates for patients in the emergency department (ED) receiving overnight imaging. METHODS: Retrospective matched cohorts of two separate years prior (prior-16 and prior-17) and 1 year after (post-18) introduction of overnight attending radiologist final reporting. Patients receiving imaging between 22:00 and 07:00 h and returned to ED within 48 h of initial visit discharge were electronically identified. String matching identified return visits possibly related to imaging completed on first visit. Identified return visit notes were scored by three observers individually. Unclear and discrepant cases were resolved by consensus meeting, using full patient charts where needed. Incidences were provided and logistic regression analysis defined if coverage model was a predictor for recall. Odds ratios were calculated. RESULTS: ED patient count with imaging completed overnight in prior-16 was 9200, in prior-17 was 9543, and in post-18 was 9992. The number of overnight imaging studies performed was respectively 13,883, 14,463, and 15,112. Imaging-related ED recalls were respectively 54, 61, and 7, a decrease with the new coverage model of 89% to true and at least 90% of expected recalls.Logistic regression demonstrated that coverage model was a significant predictor of ED recalls with chi-square of 59.86 and p < 0.001, an R2 of 0.03 (Hosmer and Lemeshow). Compared to post-18, ED patients had an odds ratio of 8.42 (prior-16) and 9.18 (prior-17) to be called back to ED. CONCLUSION: Overnight final reporting significantly decreases ED recalls for patients receiving diagnostic imaging overnight. While numbers are low even prior to rollout, the number should be minimized wherever possible to diminish patient anxiety and discomfort, reduce ED overcrowding and expedite definitive management. KEY MESSAGES/WHAT THIS PAPER ADDS: Section 1: What is already known on this subject • Radiology resident preliminary report discrepancy rates are low. • Overnight attending radiologist coverage is a model increasingly applied in academic and large non-academic centers. • Patient recalls to the ED are a burden to the patient and impact patient throughput in (over)crowded EDs. Section 2: What this study adds • First study to look at the impact of overnight attending final reports on the recall rate for ED patients with overnight imaging performed. • While absolute numbers are low, there is a significant decrease in patients returning to ED for imaging related issues after introducing overnight attending coverage. • Resident autonomy can be preserved and training enhanced while increasing patient safety and comfort.

Isogonal non-crystallographic periodic graphs based on knotted sodalite cages.

This work considers non-crystallographic periodic nets obtained from multiple identical copies of an underlying crystallographic net by adding or flipping edges so that the result is connected. Such a structure is called a `ladder' net here because the 1-periodic net shaped like an ordinary (infinite) ladder is a particularly simple example. It is shown how ladder nets with no added edges between layers can be generated from tangled polyhedra. These are simply related to the zeolite nets SOD, LTA and FAU. They are analyzed using new extensions of algorithms in the program Systre that allow unambiguous identification of locally stable ladder nets.