bluuebunny/crossref_metadata_2025 huggingface dataset:
Vulnerability to Postoperative Complications in Obstructive Sleep Apnea: Importance of Phenotypes
Authors: Altree Thomas J. , Chung Frances , Chan Matthew T. V. , Eckert Danny J.
Published: April 2021

Obstructive sleep apnea (OSA) is a common comorbidity in patients undergoing surgical procedures. Patients with OSA are at heightened risk of postoperative complications. Current treatments for OSA focus on alleviating upper airway collapse due to impaired upper airway anatomy. Although impaired upper airway anatomy is the primary cause of OSA, the pathogenesis of OSA is highly variable from person to person. In many patients, nonanatomical traits play a critical role in the development of OSA. There are 4 key traits or “phenotypes” that contribute to OSA pathogenesis. In addition to (1) impaired upper airway anatomy, nonanatomical contributors include: (2) impaired upper airway dilator muscle responsiveness; (3) low respiratory arousal threshold (waking up too easily to minor airway narrowing); and (4) unstable control of breathing (high loop gain). Each of these phenotypes respond differently to postoperative factors, such as opioid medications. An understanding of these phenotypes and their highly varied interactions with postoperative risk factors is key to providing safer personalized care for postoperative patients with OSA. Accordingly, this review describes the 4 OSA phenotypes, highlights how the impact on OSA severity from postoperative risk factors, such as opioids and other sedatives, is influenced by OSA phenotypes, and outlines how this knowledge can be applied to provide individualized care to minimize postoperative risk in surgical patients with OSA.
Outcomes of Sleep Apnea Surgery in Outpatient and Inpatient Settings
Authors: Rosero Eric B. , Joshi Girish P.
Published: April 2021

BACKGROUND:

Upper airway surgery is an alternative treatment for patients with severe obstructive sleep apnea (OSA). However, there is controversy regarding selection criteria for outpatient versus inpatient settings for these surgical procedures. The aim of this retrospective study was to compare postoperative outcomes of patients undergoing airway surgery in outpatient and inpatient settings based on length of stay at the facility.

METHODS:

The 2011–2017 American College of Surgeons National Surgical Quality Improvement databases were used to select adult patients with a diagnosis of OSA undergoing elective airway surgery procedures. Single-level (eg, uvulopalatopharyngoplasty [UPPP]) or multilevel surgery (eg, concomitant procedures on base of tongue, maxilla, palate, nose/turbinate, or tracheotomy) was identified using appropriate current procedural terminology (CPT) codes. Surgery setting was classified as outpatient (length of hospital stay = 0 days) or inpatient (length of stay ≥1 day). Propensity scores derived from logistic regression models were used to match inpatient to outpatient cases at a ratio of 1:1. Primary outcome was a composite of 30-day readmissions, reoperations, and/or postoperative complications. Outcomes between the matched groups were compared with McNemar’s tests and generalized mixed linear regression analyses.

RESULTS:

A total of 3208 cases were identified (1049 [32.7%] outpatient and 2159 [67.3%] inpatient). Inpatients were older, had more comorbidities, larger body mass index, and more multilevel procedures. UPPP was performed in about 96% of both inpatients and outpatients. The overall rate of composite of readmission, reoperations, and/or complications in the whole unmatched sample was 6.4% (6.8% and 5.5% in inpatients and outpatients, respectively). The propensity-matching algorithm produced a sample of 987 patients per surgical setting well balanced on available baseline characteristics. The incidence of the composite primary outcome was not significantly different between the groups (6.2% and 5.9% in inpatients and outpatients, respectively; odds ratio [OR] [95% confidence interval {CI}], 1.06 [0.73–1.53]; P = .77).

CONCLUSIONS:

This retrospective study found that the complications and 30-day readmission rates after airway surgery for OSA are low. There were no significant differences in the composite outcome of 30-day readmissions, reoperations, or complications between inpatient and outpatient settings. Adequately designed prospective studies are necessary to confirm the retrospective observations of this study.
Effect of Intravenous Acetaminophen on Mean Arterial Blood Pressure: A Post Hoc Analysis of the EFfect of Intravenous ACetaminophen on PosToperative HypOxemia After Abdominal SurgeRy Trial
Authors: Bravo Mauro , Bakal Omer , Rivas Eva , Mascha Edward J. , Pu Xuan , Mosteller Lauretta , Rodriguez-Patarroyo Fabio , Essber Hani , AlGharrash Ahmed , Turan Alparslan
Published: April 2021

BACKGROUND:

Acetaminophen is commonly used as part of multimodal analgesia for acute pain. The intravenous formulation offers a more predictable bioavailability compared to oral and rectal acetaminophen. There have been reports of hypotension with intravenous acetaminophen attributable to centrally mediated and vasodilatory effects. We tested the hypothesis that in adults having abdominal surgery the use of intravenous acetaminophen versus placebo for postoperative pain management is associated with a decrease in mean arterial pressure (MAP) after its administration.

METHODS:

This is a substudy of eFfect of intravenous ACetaminophen on posToperative hypOxemia after abdominal surgeRy (FACTOR) trial (NCT02156154). FACTOR trial randomly assigned adults undergoing abdominal surgery to either 1 g of acetaminophen or placebo every 6 hours during the first postoperative 48 hours. Continuous monitoring of blood pressure was obtained by noninvasive ViSi Mobile device (Sotera Wireless, Inc, San Diego, CA) at 15-second intervals during initial 48 hours postoperatively. We excluded patients without continuous monitoring data available. The primary outcome was the MAP difference between MAP 5 minutes before study drug administration (baseline) and MAP 30 minutes poststudy drug administration initiation. We used a linear mixed effects model to assess the treatment effect on MAP change. The secondary outcome was MAP area under baseline (AUB) during the 30 minutes after treatment. In a sensitivity analysis of change in MAP from predrug to postdrug administration, we instead used postdrug MAP as the outcome adjusting for the baseline MAP in the model.

RESULTS:

Among 358 patients analyzed, 182 received acetaminophen and 176 placebo. The mean (standard deviation [SD]) of average MAP change was −0.75 (5.9) mm Hg for the treatment and 0.32 (6.3) mm Hg for the placebo. Acetaminophen was found to decrease the MAP from baseline more than placebo after drug administration. The estimated difference in mean change of MAP was −1.03 (95% confidence interval [CI] −1.60 to −0.47) mm Hg; P < .001. The sensitivity analysis showed postoperative MAP in the acetaminophen group was 1.33 (95% CI, 0.76-1.90) mm Hg lower than in the placebo group (P < .001). The median of MAP AUB was 33 [Q1 = 3.3, Q3 = 109] mm Hg × minutes for the treatment and 23 [1.6, 79] mm Hg × minutes for the placebo. Acetaminophen was found to increase the AUB with an estimated median difference of 15 (95% CI, 5-25) mm Hg × minutes (P = .003).

CONCLUSIONS:

Intravenous acetaminophen decreases MAP after its administration. However, this decrease does not appear to be clinically meaningful. Clinicians should not refrain to use intravenous acetaminophen for acute pain management because of worries of hypotension.
Perioperative Management of Insomnia, Restless Legs, Narcolepsy, and Parasomnias
Authors: Hershner Shelley , Auckley Dennis
Published: April 2021

Obstructive sleep apnea (OSA) has been shown to increase risk of adverse perioperative events. More recently, investigators have begun to examine other common sleep disorders to assess how they may be impacted by the perioperative environment, as well as influence postoperative outcomes. There are a number of mechanisms by which such common sleep disorders (eg, insomnia, restless legs syndrome, narcolepsy, and parasomnias) may have consequences in the perioperative setting, both related to the underlying pathophysiology of the diseases as well as their treatments. This review will highlight the current state of the literature and offer recommendations for management of these conditions during the perioperative journey.
Identification of Sleep Medicine and Anesthesia Core Topics for Anesthesia Residency: A Modified Delphi Technique Survey
Authors: Berezin Linor , Nagappa Mahesh , Wong Jean , Clivatti Jefferson , Singh Mandeep , Auckley Dennis , Charchaflieh Jean G. , Jonsson Fagerlund Malin , Gali Bhargavi , Joshi Girish P. , Overdyk Frank J. , Margarson Michael , Mokhlesi Babak , Moon Tiffany , Ramachandran Satya K. , Ryan Clodagh M. , Schumann Roman , Weingarten Toby N. , Won Christine H.J. , Chung Frances
Published: April 2021

BACKGROUND:

Sleep disorders affect up to 25% of the general population and are associated with increased risk of adverse perioperative events. The key sleep medicine topics that are most important for the practice of anesthesiology have not been well-defined. The objective of this study was to determine the high-priority sleep medicine topics that should be included in the education of anesthesia residents based on the insight of experts in the fields of anesthesia and sleep medicine.

METHODS:

We conducted a prospective cross-sectional survey of experts in the fields of sleep medicine and anesthesia based on the Delphi technique to establish consensus on the sleep medicine topics that should be incorporated into anesthesia residency curricula. Consensus for inclusion of a topic was defined as >80% of all experts selecting “agree” or “strongly agree” on a 5-point Likert scale. Responses to the survey questions were analyzed with descriptive statistical methods and presented as percentages or weighted mean values with standard deviations (SD) for Likert scale data.

RESULTS:

The topics that were found to have 100% agreement among experts were the influence of opioids and anesthetics on control of breathing and upper airway obstruction; potential interactions of wake-promoting/hypnotic medications with anesthetic agents; effects of sleep and anesthesia on upper airway patency; and anesthetic management of sleep apnea. Less than 80% agreement was found for topics on the anesthetic implications of other sleep disorders and future pathways in sleep medicine and anesthesia.

CONCLUSIONS:

We identify key topics of sleep medicine that can be included in the future design of anesthesia residency training curricula.
Frequency and Temporal Distribution of Postoperative Respiratory Depressive Events
Authors: Driver C. Noelle , Laporta Mariana L. , Bergese Sergio D. , Urman Richard D. , Di Piazza Fabio , Overdyk Frank J. , Sprung Juraj , Weingarten Toby N.
Published: April 2021

BACKGROUND:

The frequency and temporal distribution of postoperative respiratory depression (RD) events are not completely understood. This study determined the temporal distribution and frequency of RD episodes in postsurgical patients continuously monitored by bedside capnography and pulse oximetry.

METHODS:

This was a post hoc study of a subset of postsurgical patients enrolled in The PRediction of Opioid-induced respiratory Depression In patients monitored by capnoGraphY (PRODIGY) trial from 2 sites in the United States. These patients had undergone continuous bedside monitoring on general care wards. These data were adjudicated for potential RD episodes. The number of RD episodes per patient and the time of each RD episode were determined. The first RD episode experienced by a patient was classified as an “initial” episode, and the initial and all subsequent RD episodes experienced by a patient were classified as “all” episodes. A PRODIGY risk score was calculated.

RESULTS:

Data analyzed from 250 patients contained 2539 RD episodes in 155 (62.0%, 95% confidence interval, 55.7-68.0) patients with median 2 [0–8], range of 0–545 RD episodes per patient, with a PRODIGY risk score distribution of 100 (40.0%) low, 79 (31.6%) intermediate, 70 (28.0%) high (missing data from 1 patient). Median time to the initial RD episode was 8.8 [5.1–18.0] hours postoperatively. There was a peak occurrence of initial RD events between 14:00 and 20:00 on the day of surgery, and these were associated with a large number of subsequent events in the same timeframe. The peak time of all RD episodes occurred from 02:00 to 06:00. Patients with high PRODIGY risk scores had higher incidence and greater number of RD episodes per patient (P < .001, overall comparisons between groups for both incidence [χ2] and number of episodes [Kruskal-Wallis test]).

CONCLUSIONS:

Continuous monitoring of surgical patients demonstrates that RD episodes are common, and risk increases with higher PRODIGY scores. In this patient cohort, the rate of initial RD episodes peaked in the afternoon to early evening, while peak rate of all RD episodes occurred in early morning. Further, among patients with RD episodes, the number of episodes increased with higher PRODIGY scores.
Integrating Sleep Knowledge Into the Anesthesiology Curriculum
Authors: Singh Mandeep , Gali Bhargavi , Levine Mark , Strohl Kingman , Auckley Dennis
Published: April 2021

There is common ground between the specialties of anesthesiology and sleep medicine. Traditional sleep medicine curriculum for anesthesiology trainees has revolved around the discussion of obstructive sleep apnea (OSA) and its perioperative management. However, it is time to include a broader scope of sleep medicine–related topics that overlap these specialties into the core anesthesia residency curriculum. Five main core competency domains are proposed, including SLeep physiology; Evaluation of sleep health; Evaluation for sleep disorders and clinical implications; Professional and academic roles; and WELLness (SLEEP WELL).

The range of topics include not only the basics of the physiology of sleep and sleep-disordered breathing (eg, OSA and central sleep apnea) but also insomnia, sleep-related movement disorders (eg, restless legs syndrome), and disorders of daytime hypersomnolence (eg, narcolepsy) in the perioperative and chronic pain settings. Awareness of these topics is relevant to the scope of knowledge of anesthesiologists as perioperative physicians as well as to optimal sleep health and physician wellness and increase consideration among current anesthesiology trainees for the value of dual credentialing in both these specialties.
How Nearby Homicides Affect Young Women's Pregnancy Desires: Evidence From a Quasi-Experiment
Authors: Weitzman Abigail , Barber Jennifer S. , Heinze Justin , Zimmerman Marc
Published: April 2021

Leveraging spatiotemporal variation in homicides that occurred during a 2.5-year weekly panel survey of 387 women ages 18–22 in Flint, Michigan, we investigate how young women's desires to become pregnant and to avoid pregnancy evolve in response to local homicides during the transition to adulthood. To address the endogeneity of exposure, we explore how the same woman's pregnancy desires (1) differed, on average, across weeks before and after the first homicide occurred within a quarter mile of her home; (2) evolved in the aftermath of this initial homicide exposure; and (3) changed in response to additional nearby homicides. One-fifth (22%) of women were exposed to a nearby homicide at least once during the study, and one-third of these women were exposed multiple times. Overall, the effects of nearby homicides were gradual: although average desires to become pregnant and to avoid pregnancy differed after initial exposure, these differences emerged approximately three to five months post-exposure. Repeated exposure to nearby homicides had nonlinear effects on how much women wanted to become pregnant and how much they wanted to avoid pregnancy. Together, our analyses provide a new explanation for why some young women—especially those who are socially disadvantaged—desire pregnancy at an early age.
Introduction
Authors: Snaza Nathan , Singh Julietta
Published: April 2021

This introduction to the special issue “Educational Undergrowth” proposes an ecological view of educational institutions and practices, one that foregrounds the porosity of borders so that entities and institutions that can sometimes seem distinct are thought of as always entangled. The editors elaborate this ecological view by drawing on theories of coloniality, especially the work of Sylvia Wynter (and her human/Man distinction) and Stefano Harney and Fred Moten (in The Undercommons). In this framing, the university appears as a specific, but not isolated, part of a colonial ecology structured around producing Man. This allows both for critical accounts of how coloniality shapes institutions such as schools and universities, always in relation to many other institutions and sites, and for speculative experiments in queer, decolonial, abolitionist education. The introduction intervenes in contemporary leftist debates about the university in particular and education more generally by offering a way of attuning to critical, abolitionist, and decolonial projects as specific but intraactive outgrowths of the colonial ecology and myriad disruptive projects (happening both in and outside of institutionalized schools). On the one hand, educational undergrowth accounts for how resources circulate unevenly in the colonial ecology so that the “growth” of some people, institutions, and projects is possible only because others are deprived, defunded, and disinvited. On the other hand, it draws on affect theory, new materialisms, and work in decolonial and critical ethnic studies to valorize otherwise marginal, bewildering, errant educational encounters that are always taking place in the undergrowth of the university.
Beyond Land Acknowledgment in Settler Institutions
Authors: Stewart-Ambo Theresa , Yang K. Wayne
Published: April 2021

What does land acknowledgment do? Where does it come from? Where is it pointing? Existing literature, especially critiques by Indigenous scholars, unequivocally assert that settler land acknowledgments are problematic in their favoring of rhetoric over action. However, formal written statements may challenge institutions to recognize their complicity in settler colonialism and their institutional responsibilities to tribal sovereignty. Building on these critiques, particularly the writings of Métis cultural producer Chelsea Vowel, this article offers beyond as a framework for how institutional land acknowledgments can or cannot support Indigenous relationality, land pedagogy, and accountability to place and peoples. The authors describe the critical differences between Indigenous protocols of mutual recognition and settler practices of land acknowledgment. These Indigenous/settler differences illuminate an Indigenous perspective on what acknowledgments ought to accomplish. For example, Acjachemen/Tongva scholar Charles Sepulveda forwards the Tongva concept of Kuuyam, or guest, as “a reimagining of human relationships to place outside of the structures of settler colonialism.” What would it mean for a settler speaker of a land acknowledgment to say, “I am a visitor, and I hope to become a proper guest”? Two empirical examples are presented: the University of California, Los Angeles, where an acknowledgment was crafted in 2018; and the University of California, San Diego, where an acknowledgment is under way in 2020. The article concludes with beyond as a potential decolonial framework for land acknowledgment that recognizes Indigenous futures.
Stained University
Authors: Gonzalez Jaime Acosta , Meyerhoff Eli
Published: April 2021

Duke University was founded on tobacco wealth, and now it has a tobacco-free campus. How should we understand this change? How can communities around this university, and higher education broadly, reckon with our historical and ongoing complicities with tobacco capitalism? This article examines how the individualized subject has been historically constructed, in response to resistances, through supplementary relations between the university and tobacco industries. With abolitionist university studies, the authors focus on the postslavery university as a key site for these individualizing processes. They situate Duke as a nexus of new means of capitalist accumulation, including, on the one hand, the postslavery university as an institution for disciplining, individualizing, and differentiating wage laborers and, on the other, the tobacco industry's shift to monopolization and mass consumption of tobacco commodities. The long Black freedom movement continues in the post-WWII era with resistances that push capitalism into crisis, while simultaneously, capitalism's coping mechanism of tobacco use has the unintended consequence of mass death. This article explores how, at the site of Duke, part of capitalism's response to resistance movements has been to deepen the individualization processes, charging individuals with taking on responsibility for the costs of both tobacco use and higher education. The authors ask how narratives of smoke-free and tobacco-free campuses could interlink with postracial narratives to obscure how the tobacco companies and universities have accumulated capital through racism, deception, dispossession, and exploitation.
The lobster optic lamina IV: Glial cells
Authors: Hámori J. , Horridge G. A.
Published: April 2021

There are 3 distinct types of glial cells in the optic lamina of the lobster: dark, light, and sheet cells, all distinguished from the neurons by being multipolar and not having dictyosomes. Dark cells are surrounded by intercellular material and together with light cells constitute a structural support for the groups of nerve cells. Light cells are also sheath cells for the neuron somata. The sheet cells have numerous flat processes which together form the 2 glial layers in which the synaptic region is sandwiched. An extensive system of extracellular cisterns between the sheet processes may serve for fluid transport towards the fibres and synapses, and the numerous vesicles in the sheet cells may represent an extension of the extracellular transport system.
Growth inhibition of polyoma transformed cells by contact with static normal fibroblasts
Authors: Stoker M. G. P. , Shearer Moira , O’Neill C.
Published: April 2021

The growth of polyoma-transformed BHK21 cells was studied in mixed cultures with normal mouse fibroblasts. On coverslips in excess medium, normal fibroblasts undergo one or two divisions after the cells become contiguous. Py-cell growth was not inhibited by contact with confluent fibroblasts which were still dividing, but the Py cells were rapidly inhibited after contact with fibroblasts which had become static. Further experiments confirmed the earlier view that the inhibitory effect was not due to a general change in the medium but was only brought about when cells were in contact or close proximity.
Characterization of the Atrial Natriuretic Factor System in Lungs of the Toad Bufo Paracnemis
Authors: Glass Mogens L. , Branco Luiz G. S. , Antunes-Rodrigues José , Gutkowska Jolanta
Published: April 2021

Blood pressure in the amphibian pulmonary circulation is relatively high because a single ventricle serves both the systemic and pulmonary circulation, creating a high degree of plasma filtration from pulmonary capillaries. Previous studies have shown that lung atrial natriuretic factor (ANF) may have an important physiological function in preventing edema in mammals. In this study, we report the presence of the complete ANF system in the lungs of the toad Bufo paracnemis. Radioimmunoassay of tissue homogenates revealed that toad lung ANF concentration was approximately twice as high (928.5±83.0 pg mg−1 protein) as that of lung tissue in mammals of a similar size. The amount of ANF was significantly higher in the left than in the right atrium (15.0±1.2 versus 1.9±0.8 ng mg−1 protein; N=4, P<0.001), while the ventricle contained 488.3±41.8 pg mg−1 protein. In extracts of both lungs and atria, high-performance liquid chromatography revealed two forms of the peptide; prohormone and a carboxy-terminal peptide of low molecular mass, which is the biologically active form of peptide. The presence of the prohormone suggests that ANF is synthesized in toad lungs and atria. Characterization of toad lung receptors by a competitive binding assay demonstrated three different subtypes of ANF receptors: the guanylyl cyclase (GC) receptors, GC-A and GC-B, as well as clearance (C) receptors. We conclude that the toad Bufo paracnemis has a well-developed complete ANF system in the lung, suggesting that it has a role in toad lung physiology.
How Well are Frequency Sensitivities of Grasshopper Ears Tuned to Species-Specific Song Spectra?
Authors: Meyer Jens , Elsner Norbert
Published: April 2021

Grasshoppers of 20 acridid species were examined using spectral analysis, laser vibrometry and electrophysiology to determine whether the song spectra, the best frequencies of tympanal-membrane vibrations and the threshold curves of the tympanal nerves are adapted to one another. The songs of almost all species have a relatively broad-band maximum in the region between 20 and 40 kHz and a narrower peak between 5 and 15 kHz. There are clear interspecific differences in the latter, which are not correlated with the length of the body or of the elytra. At the site of attachment of the low-frequency receptors (a-cells), the tympanal membrane oscillates with maximal amplitude in the region from 5 to 10 kHz. At the attachment site of the high-frequency receptors (d-cells), there is also a maximum in this region as well as another around 15–20 kHz. The tympanal nerve is most sensitive to tones between 5 and 10 kHz, with another sensitivity maximum between 25 and 35 kHz. The species may differ from one another in the position of the low-frequency peaks of the membrane oscillation, of the nerve activity and of the song spectra. No correlation was found between the characteristic frequency of the membrane oscillation and the area of the tympanal membrane.

Within a given species, the frequency for maximal oscillation of the membrane at the attachment site of the low-frequency receptors and the frequency for maximal sensitivity of the tympanal nerve are in most cases very close to the low-frequency peak in the song spectrum. In the high-frequency range, the situation is different: here, the position of the peak in the song spectrum is not correlated with the membrane oscillation maximum at the attachment site of the high-frequency receptors, although there is a correlation between the song spectrum and the sensitivity of the tympanal nerve. On the whole, therefore, hearing in acridid grasshoppers is quite well adjusted to the frequency spectra of the songs, partly because the tympanal membrane acts as a frequency filter in the low-frequency range.
Not all swellings are dental abscesses: A cautionary tale
Authors: Biyani Prateek , Lundgren Rachael , Thompson Alexandra , Orr Robert
Published: April 2021

Carcinomas of the maxillary antrum are rare and tend to present late, leading to poor survival rates. Two-thirds of cases will present with oral symptoms or facial swelling. Dentists should be aware of suspicious clinical and radiographic signs, which may help in early detection and treatment. We present the case of a 48-year-old female complaining of facial swelling. In preceding months, she had visited her GP and dentist numerous times, receiving antibiotics from each for suspected sinusitis and a dental abscess, respectively. Subsequent investigations confirmed an SCC of the right maxillary antrum, which unfortunately, could only be treated palliatively.

CPD/Clinical Relevance: The reader should understand the classic findings for a maxillary antrum carcinoma. They should also increase their confidence and awareness in identifying red flag signs and symptoms.
Garré's osteomyelitis of the jaw
Authors: Hazara Roya , Pappa Elena
Published: April 2021

The aim of this short review is to update dental professionals on the causes, manifestation and treatment of Garré's osteomyelitis. There are multiple cause of facial swellings and asymmetry arising from dental infections, trauma, or more seriously can be benign or malignant tumours. Garré's osteomyelitis is most commonly seen in children and young adults and persists until the cause is removed. Other lesions such as fibrous dysplasia, sarcoma and chondrosarcoma can manifest in the same manner as Garré's osteomyelitis clinically. Garrés’ osteomyelitis can be result of a chronic infection or trauma. Dentists and dental professionals must be aware of the causes, minvestigations required and provide the appropriate treatment. Information was collected using Medline, Pubmed and Athens to access the journals.

CPD/Clinical Relevance: This article highlights the importance of recognizing Garré's osteomyelitis in children and young adults, identifying the cause and treating them appropriately. It is imperative for dental professionals to know and refer to relevant specialties for further investigation.
Alveogyl: Foreign Body Reaction
Authors: Joshi Sandeep , Steel Clare , Eyeson Josiah
Published: April 2021

Alveolar osteitis (AO) is a painful complication experienced by approximately 3–4% of patients who have undergone a dental extraction. A frequently used intra-alveolar dressing material, such as Alveogyl is commonly used to treat sockets where a diagnosis of AO is made. However, unexpected problems may be encountered by the dentist when using such materials and this article explores a case where a diagnosis of a foreign body reaction to Alveogyl was identified in a symptomatic patient with no overt clinical or radiographical signs.

CPD/Clinical Relevance: Dental professionals should be aware of the possible complications with the use of Alveogyl in the treatment of alveolar osteitis, in particular foreign body reactions.
Replacing buried teeth: A Review of primary failure of eruption of permanent teeth and case report
Authors: Chin Jann Siew , Thomas Matthew BM
Published: April 2021

Primary failure of eruption is a condition that has variable presentation and can be difficult to diagnose. This article provides an overview of the condition and discusses the management of an unusual case of primary failure of eruption of permanent teeth in a 37-year-old adult.

CPD/Clinical Relevance: Where surgical and orthodontic options are unpredictable, restorative management alone may achieve successful functional and aesthetic outcomes for cases involving primary failure of eruption of permanent teeth.
Beyond the Fan-Hoffman inequality
Authors: Drury Stephen
Published: April 2021

We establish a singular value inequality inspired by the Fan-Hoffman inequality and resolve the $j$-conjecture of Yang and Zhang.
Multiple Fano resonances excitation on all-dielectric nanohole arrays metasurfaces
Authors: Yang Lei , Yu ShiLin , Li Hao , Zhao TongGang
Published: April 2021

Both toroidal dipoles, electric dipoles and magnetic dipoles belong to one type of electromagnetic excitation. In this paper, we present an all-dielectric metasurface composed of an array of square nanoholes. It can simultaneously generate four resonance responses excited by TD, EQ and MD in the continuous near-infrared band. By introducing the in-plane symmetry breaking of the unit cell, asymmetric dielectric nanohole arrays are used to achieve two quasi-BIC resonance modes with high Q-factors excited by EQ and MD. The paper theoretically analyzes and demonstrates the relationship between structural asymmetry and the radiative Q-factor of two Fano resonances, that are governed by symmetry-protected BICs. And multipole decomposition and near-field analysis are performed to demonstrate the dominant role of various electromagnetic excitations in the four modes. The spectra response is also calculated for different incident polarization angles and medium refractive indices. The proposed metasurface is more feasible and practical compared to other complex nanostructures, which may open avenues for the development of applications such as biochemical sensing, optical switches and optical modulators, and provide a reference for the design of devices with polarization-independent properties.
Ultra-narrowband absorption filter based on a multilayer waveguide structure
Authors: Peng Wan , Zhang Guiju , Lv Yuanshuai , Qin Linling , Qi Kaiyue
Published: April 2021

We propose a six-layer waveguide structure embedded in a single-layer grating based on guided-mode resonance (GMR), which can realize ultra-narrowband filtering with a tunable resonance wavelength. The filtering characteristics were analyzed and calculated by rigorous coupled-wave analysis (RCWA) and COMSOL Multiphysics. The narrowband resonance wavelength and absorption are tuned by changing the geometry and physical parameters of the structure such as the grating period and width, layer thickness, and materials. We designed and calculated the full width at half maximum (FWHM) and resonance absorption spectra in detail under different polarization states of electromagnetic waves. We obtained an absorption FWHM of 8.51e-5 nm for the transverse electric (TE) mode and 0.023 nm for the transverse magnetic (TM) mode, with the absorption coefficients having a value over 99.2%. The GMR filtering structure shows a good sensitivity and figure of merit (FOM) for refractive index sensing. For instance, a very high FOM of 17782.6/RIU for TM incidence is observed. These structures can have possible applications in optical information devices and sensors.
100 Gbit/s co-designed optical receiver with hybrid integration
Authors: Li Weizhong , Zhang Hongguang , Hu Xiao , Lu Donglai , Chen Daigao , Chen Sikai , He Jian , Wang Lei , Qi Nan , Xiao Xi , Yu Shaohua
Published: April 2021

We demonstrate a co-designed optical receiver, which is hybrid-integrated with a silicon-photonic photodetector (PD) and silicon-germanium (SiGe) trans-impedance amplifier (TIA). Accurate equivalent circuit models of PD and electrical parasitic of chip-on-board (COB) assembly are built for co-simulation with TIA. Inductive peaking and equalizer (EQ) techniques are proposed in the design of TIA to extend the bandwidth of the optical receiver. The measured electrical 3-dB bandwidth of TIA and optical-to-electrical (O-E) 3-dB bandwidth of optical receiver are above 36.8 GHz and 36 GHz, respectively. For the optical receiver, clear eye diagrams up to a data rate of 80 Gbit/s are realized. The bit-error ratios (BER) for the NRZ signal with a different bit rate and received optical power are experimentally measured, and 100 Gbit/s NRZ operation is successfully achieved with a soft-decision forward error correction (SD-FEC) threshold.
Curved periodic ripples fabricated by double time-delayed femtosecond laser beams on the silicon surface
Authors: Xiao Chunhui , Wang Tingyuan , Wang Xiaolei , Lin Lie , Gu Bing , Zhang Nan , Liu Weiwei
Published: April 2021

Laser-induced periodic surface structure (LIPSS) is an important, high-throughput surface nano-structuring method, which has been used to fabricate various functional surfaces. In this paper, we fabricate double time-delayed orthogonally polarized femtosecond laser beams with a fixed beam power ratio of 1.5:1 that are employed to irradiate the silicon surface and curved periodic ripples with a sub-wavelength period. It is found that the local orientation of the ripples on the silicon surface can be modulated in a range of 0-80° by adjusting the fabrication parameters, such as the laser fluence, the target scanning speed, and the time delay between double laser beams. The transition from the curved ripples to the straight ripples can be achieved by increasing the target scanning speed. Different from previous studies that the curved periodic ripples are fabricated by modulating the laser polarization, the method demonstrated here utilizes the interaction between the linearly polarized subsequent laser beam and the preceding laser beam excited silicon to form curved ripples.
Widely tunable, low linewidth, and high power laser source using an electro-optic comb and injection-locked slave laser array
Authors: Skehan J. Connor , Naveau Corentin , Schroder Jochen , Andrekson Peter
Published: April 2021

We propose and implement a tunable, high power and narrow linewidth laser source based on a series of highly coherent tones from an electro-optic frequency comb and a set of 3 DFB slave lasers. We experimentally demonstrate approximately 1.25 THz (10 nm) of tuning within the C-Band centered at 192.9 THz (1555 nm). The output power is approximately 100 mW (20 dBm), with a side band suppression ratio greater than 55 dB and a linewidth below 400 Hz across the full range of tunability. This approach is scalable and may be extended to cover a significantly broader optical spectral range.
Generation of coherent multicolor noise-like pulse complex in Yb-doped fiber laser mode-locked by GIMF-SA
Authors: Chang Shuo , Wang Hailong , Wang Zhaokun , Yang Hailong
Published: April 2021

We have demonstrated the generation of multicolor noise-like pulse complex in a passively Yb-doped mode-locked fiber laser based on a single mode-graded index multimode-single mode fiber (SMF-GIMF-SMF) device as the saturable absorber (SA). The stimulated Raman scattering (SRS) effect leads to the cascaded generation of the main noise-like pulse (NLP) at 1028.8 nm together with the noise like Raman pulse (RP) at 1076.1 nm. The generated dual wavelength pulses demonstrate the unique properties of mutually synchronization and coherence. The autocorrelation traces show that each of the synchronously mode-locked pulses exhibits a double-scale structure with a narrow peak which consists of a train of quasi-periodic beat pulses with a 35.7 fs pulse width and a pulse separation of about 77.2 fs. The total output power reaches 102.5 mW with 34% of it belonging to the RP. And furthermore, by separating the two pulses with spectral filters, the modulation fringes cannot be observed anymore. These results indicate that the Raman component participates in the mode-locking operation as a ‘signal’ instead of ‘noise’. Such a coherent Raman pulse source provides a novel platform for numerous applications, such as frequency comb spectroscopy and so on.
Static laser speckle suppression using liquid light guides
Authors: Guo Yanyu , Deng Jiayu , Li Jiapo , Zhou Jun , Cai Di , Le Zichun
Published: April 2021

Static laser speckle suppression using multimode fibers has practical limitations as the technique requires an extremely long fiber to achieve an acceptable speckle contrast. An effective method based on liquid light guides was developed in this study to suppress laser speckle. In this study, a speckle simulation model of the liquid light guide was established for numerically calculating the speckle contrast without solving the analytical solution of the photon diffusion equation. The obtained simulation results were compared with the experimental results for the dependence of speckle contrast on the required length and numerical aperture with different liquid core types of liquid light guides. A speckle contrast of 12% and a speckle suppression efficiency of 5 was achieved at the end of a 2.4 m long liquid light guide. For the same fiber length, liquid light guides were found to suppress speckle more efficiently when compared to multimode fibers.
Superconducting acousto-optic phase modulator
Authors: Okada Ayato , Yamazaki Rekishu , Fuwa Maria , Noguchi Atsushi , Yamaguchi Yuya , Kanno Atsushi , Yamamoto Naokatsu , Hishida Yuji , Terai Hirotaka , Tabuchi Yutaka , Usami Koji , Nakamura Yasunobu
Published: April 2021

We report the development of a superconducting acousto-optic phase modulator fabricated on a lithium niobate substrate. A titanium-diffused optical waveguide is placed in a surface acoustic wave resonator, where the electrodes for mirrors and an interdigitated transducer are made of a superconducting niobium titanium nitride thin film. The device performance is evaluated as a substitute for the current electro-optic modulators, with the same fiber coupling scheme and comparable device size. Operating the device at a cryogenic temperature (T = 8 K), we observe the length–half-wave-voltage (length–Vπ) product of 1.78 V·cm. Numerical simulation is conducted to reproduce and extrapolate the performance of the device. An optical cavity with mirror coating on the input/output facets of the optical waveguide is tested for further enhancement of the modulation efficiency. A simple extension of the current device is estimated to achieve an efficient modulation with Vπ = 0.27 V.
Distributed transverse-force sensing along a single-mode fiber using polarization-analyzing OFDR: erratum
Authors: Feng Ting , Zhou Junnan , Shang Yanling , Chen Xiaojun , Yao X. Steve
Published: April 2021

We correct an inaccurate statement on the birefringence measurement using the PA-OFDR in our previous publication [Opt. Express 28, 31253 (2020)10.1364/OE.405682].
Development and Validation of a Clinical-Genetic Risk Score to Predict Hepatic Encephalopathy in Patients With Liver Cirrhosis
Authors: Gil-Gómez Antonio , Ampuero Javier , Rojas Ángela , Gallego-Durán Rocío , Muñoz-Hernández Rocío , Rico María C. , Millán Raquel , García-Lozano Raúl , Francés Rubén , Soriano Germán , Romero-Gómez Manuel
Published: April 2021

INTRODUCTION:

We aimed to define the impact of the genetic background on overt hepatic encephalopathy (HE) in patients with liver cirrhosis by developing a combined clinical-genetic risk score.

METHODS:

Patients suffering from liver cirrhosis from the outpatient clinics of 4 hospitals (n = 600) were included and followed up for at least 5 years until HE bouts, liver transplant, or death. Patients were genotyped for 60 candidate single nucleotide polymorphisms together with the microsatellite in the promoter region of the gene GLS.

RESULTS:

Single nucleotide polymorphisms rs601338 (FUT2), rs5743836 (TRL9), rs2562582 (SLC1A3), rs313853 (SLC1A5), and GLS microsatellite did predict independently the incidence and severity of overt HE and were included as genetic score. Competing risk analysis revealed that bilirubin (subhazard ratio [sHR] 1.30 [1.15–1.48], P < 0.001), albumin (sHR 0.90 [0.86–0.93], P < 0.001), genetic score (sHR 1.90 [1.57–2.30], P < 0.001), and previous episodes of overt HE (sHR 2.60 [1.57–4.29], P < 0.001) were independently associated to HE bouts during the follow-up with an internal (C-index 0.83) and external validation (C-index 0.74). Patients in the low-risk group had 5% and 12% risk of HE at 1 (log-rank 92.1; P < 0.001) and 5 (log-rank 124.1; P < 0.001) years, respectively, whereas 36% and 48% in the high-risk group.

DISCUSSION:

The genetic background influenced overt HE risk and severity. The clinical-genetic HE Risk score, which combined genetic background together with albumin, bilirubin, and previous episodes of overt HE, could be a useful tool to predict overt HE in patients with cirrhosis.
Accuracy of Screening Tests for Celiac Disease in Asymptomatic Patients With Type 1 Diabetes
Authors: Gould Michelle J. , Mahmud Farid H. , Clarke Antoine B.M. , McDonald Charlotte , Saibil Fred , Punthakee Zubin , Marcon Margaret A.
Published: April 2021

INTRODUCTION:

To evaluate the diagnostic performance of celiac serologic tests in asymptomatic patients with type 1 diabetes (T1D).

METHODS:

Patients with T1D asymptomatic for celiac disease were prospectively screened with immunoglobulin A anti-tissue transglutaminase. Test characteristics were calculated and optimal cutoffs for a positive screen determined.

RESULTS:

Two thousand three hundred fifty-three patients were screened and 101 proceeded to biopsy. The positive predictive value of immunoglobulin A anti-tissue transglutaminase at the assay referenced upper limit of normal (30CU) was 85.9%, and the sensitivity and specificity were 100% and 38%, respectively.

DISCUSSION:

Thresholds extrapolated from the general population for the diagnostic evaluation of celiac disease are not suitable for use in asymptomatic T1D patients. Population-specific screening cutoffs are required.
Validation of Tools for Predicting Incident Adenocarcinoma of the Esophagus or Esophagogastric Junction
Authors: Rubenstein Joel H. , Raghunathan Trivellore , Doan Cecilia , Schneider Jennifer , Zhao Wei , Metko Valbona , Nofz Kimberly , Khodadost Maryam , Corley Douglas A.
Published: April 2021

INTRODUCTION:

Guidelines suggest screening of individuals who are at increased risk of esophageal adenocarcinoma (EAC). Tools for identifying patients at risk of Barrett's esophagus have been validated. Here, we aimed to compare and validate the tools for the primary outcomes of interest: EAC and esophagogastric junction adenocarcinoma (EGJAC).

METHODS:

Retrospective longitudinal analysis of the Kaiser Permanente Northern California Multiphasic Health Checkup Cohort, a community-based cohort including 206,974 patients enrolled between 1964 and 1973 followed through 2016. Baseline questionnaires and anthropometrics classified predictor variables for each tool and were linked to cancer registry outcomes. Analyses used logistic regression, Cox proportional hazards regression, and Kaplan-Meier survival curves.

RESULTS:

We identified 168 incident EAC cases and 151 EGJAC cases at a mean of 32 years after enrollment (mean follow-up among controls 26 years). Gastroesophageal reflux disease (GERD) symptoms predicted incident EAC (hazard ratio 2.66; 95% confidence interval 1.01, 7.00), but not EGJAC. The Nord-Trøndelag Health Study tool, Kunzmann tool, and Michigan Barrett's Esophagus pREdiction Tool were more accurate than GERD for predicting EAC, with individuals in the fourth quartile of Kunzmann having 17-fold the risk of those in the 1st quartile (hazard ratio = 16.7, 95% confidence interval = 4.72, 58.8). Each tool also predicted incident EGJAC with smaller magnitudes of effect.

DISCUSSION:

The study independently validated 4 tools for predicting incident EAC and EGJAC in a large community-based population. The Kunzmann tool appears best calibrated; all appear preferable to using GERD alone for risk stratification. Future studies should determine how best to implement such tools into clinical practice.
Effect of Aging Temperature and Time on Secondary Phase Precipitation and Texture in an Ultrafine Grained 2205 Duplex Stainless Steel after Cold Rolling
Authors: Wolf Witor , Inácio Lóren Kelly de Paula , Brandão Santos Dagoberto
Published: April 2021

The present work evaluates the precipitation of secondary phases in a cold-rolled ultrafine-grained 2205 duplex stainless steel after aging at temperatures ranging from 600°C to 950°C for different annealing times (300–86,400 s). X-ray diffraction, scanning electron microscopy coupled with electron backscattered diffraction, and transmission electron microscopy were used for microstructural characterization. Mechanical properties were evaluated using tensile and Vickers microhardness tests. σ- (sigma), χ- (chi), and chromium carbide (M23C6) phases were identified. σ- and austenite phase volume fractions increased with aging time, whereas χ-phase and carbides remained nearly constant, and the ferritic volume fraction decreased. Inverse pole figures of σ-phase, for a specimen aged at 850°C for 24 h, showed a localized distribution of orientations, normal to the rolling direction, being centered around the [001], whereas for the other annealing conditions, a concentration between the orientations [001] and [110] was observed. Although mechanical strength was increased, the ductility was reduced as the secondary phase precipitation proceeded.