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Deep learning using convolutional neural networks represents a form of artificial intelligence where computers recognise patterns and make predictions based upon provided datasets. This study aimed to determine if a convolutional neural network could be trained to differentiate the location of the anterior ethmoidal artery as either adhered to the skull base or within a bone ‘mesentery’ on sinus computed tomography scans.
Coronal sinus computed tomography scans were reviewed by two otolaryngology residents for anterior ethmoidal artery location and used as data for the Google Inception-V3 convolutional neural network base. The classification layer of Inception-V3 was retrained in Python (programming language software) using a transfer learning method to interpret the computed tomography images.
A total of 675 images from 388 patients were used to train the convolutional neural network. A further 197 unique images were used to test the algorithm; this yielded a total accuracy of 82.7 per cent (95 per cent confidence interval = 77.7–87.8), kappa statistic of 0.62 and area under the curve of 0.86.
Convolutional neural networks demonstrate promise in identifying clinically important structures in functional endoscopic sinus surgery, such as anterior ethmoidal artery location on pre-operative sinus computed tomography.
The Murchison Widefield Array (MWA) is an open access telescope dedicated to studying the low-frequency (80–300 MHz) southern sky. Since beginning operations in mid-2013, the MWA has opened a new observational window in the southern hemisphere enabling many science areas. The driving science objectives of the original design were to observe 21 cm radiation from the Epoch of Reionisation (EoR), explore the radio time domain, perform Galactic and extragalactic surveys, and monitor solar, heliospheric, and ionospheric phenomena. All together
programs recorded 20 000 h producing 146 papers to date. In 2016, the telescope underwent a major upgrade resulting in alternating compact and extended configurations. Other upgrades, including digital back-ends and a rapid-response triggering system, have been developed since the original array was commissioned. In this paper, we review the major results from the prior operation of the MWA and then discuss the new science paths enabled by the improved capabilities. We group these science opportunities by the four original science themes but also include ideas for directions outside these categories.
Polycyclic aromatic hydrocarbons (PAHs) may contribute to obesity. Childhood obesity is a strong predictor of adult obesity and morbidity; however, the relationship between PAHs and obesity in young children (e.g., aged 3–5) has not been studied. We examined the association between urinary PAH metabolites and measures of obesity in children. We analyzed data from 3667 children aged 3–18 years who participated in the Canadian Health Measures Survey (CHMS, 2009–2015). We ran separate multivariable linear models to estimate the association between quartiles of PAH metabolites and each of body mass index (BMI) percentile, waist circumference (WC), and waist-to-height ratio (WHtR) in the total population, as well as in the age subgroups 3–5, 6–11, and 12–18, adjusting for age, sex, ethnicity, education, income quintile, diet, creatinine, and exposure to environmental tobacco smoke. A multinomial logistic regression model estimated adjusted odds ratios for risk of central obesity. BMI, WC, and WHtR were positively associated with total PAH and naphthalene metabolites in the total population aged 3–18 and in age groups 6–11 and 12–18. In 3–5 year olds, WHtR, but not BMI, was significantly associated with total PAH, naphthalene, and phenanthrene metabolites. Overall, those in the highest quartile for naphthalene or total PAH metabolites had three times greater odds of having central obesity compared with those in the lowest quartile. Urinary PAH metabolites are associated with WHtR, an indicator of central obesity and predictor of health risks associated with obesity, in children as young as 3–5.
At some time during one’s practice in anaesthesiology, one cannot help but notice certain obsessive–compulsive tendencies in our colleagues. Such traits are quickly revealed when you put them under pressure by asking them to do an unplanned emergency case and disrupt the cocoon that is their elective list. In contrast to having known and prepared for all of the patient’s problems, they are now compelled to deal with a relatively unknown and often sub-optimal situation. More likely than not, they will have to induce anaesthesia with rapid sequence induction (RSI). Whereas some may be thrilled, others are less impressed with the disorder introduced into their world. What is it about emergency cases that should be such a bother? In particular, can TIVA enthusiasts thrive in this environment? At the time of writing, the use of TIVA in emergency is indeed somewhat uncharted territory as very few studies have examined this area.
In keeping with the spirit of producing a practical book, we took editorial privileges and removed some of the more detailed text from various chapters and yet felt it would be a waste if some of it weren’t shared with our readers. At the same time, there are aspects of TIVA that are not necessarily recommended for novices but may entice those who have had a bit of experience and want to extend their TIVA repertoire. Therefore we thought we would create a final chapter that would incorporate some such material, hopefully in a semi-logical fashion.
The arrival of versatile, easy-to-use, commercially available, target-controlled drug delivery systems have simplified TIVA making it as simple as using a vaporiser. Most have a choice of PK algorithms. The Marsh and Schnider models are the most commonly used for propofol and have various pros and cons. However, the important point about these models is that they can both make proportional changes in blood concentration allowing easy titration. New data is becoming available for more precise keo and PK that will improve accuracy – and therefore new models are likely to be developed. Remifentanil can also be administered with TCI using the Minto model but, as the pharmacokinetics are relatively simple, can also be delivered as an ordinary infusion (µg.kg−1.min−1). The use of these techniques is discussed elsewhere in the book so here we will concentrate on how to physically set up your TIVA system.
Like many of you, we’re sure, we were trained to use IV anaesthetic agents for induction of anaesthesia but volatiles for maintenance – a sensible and seemingly safe combination that has been used for decades. So why change? The initial attraction of TIVA was the extremely rapid, smooth and clear-headed recovery of patients when using propofol as the hypnotic component of an anaesthetic. This is particularly apparent when the drug is used for cases of short to intermittent duration, for example in day-case surgery with earlier discharge from the post-anaesthetic care unit. Clearly in modern practice, which is moving towards shorter in-patient stays, this represents a major advantage. In addition, improved levels of patient satisfaction occur with TIVA, presumably due to the favourable recovery profile. Certainly, desflurane and sevoflurane allow rapid recovery but it is not as smooth, there may be more emergence delirium and quality indicators are not as good.
Total intravenous anaesthesia (TIVA) is an innovative alternative to traditional inhalational anaesthesia. Often incorrectly perceived as overly complex, TIVA has numerous advantages over inhalational drugs, such as a lower risk of nausea, less pain and better cognitive recovery. Taking on TIVA is a practical, easy to read and engaging guide to TIVA. It demystifies this important technique and will empower the novice but also support more experienced practitioners. It is a clear step-by-step approach to treating everything from routine elective to paediatric, geriatric, obese and pregnant patients. Pharmacokinetic models, dosage calculations, and the use of TIVA in emergency medicine are also elucidated. Written by international experts in the field with many years of experience both conducting and teaching TIVA, this handbook is an essential resource for experienced and novice anaesthetists alike who want to improve their understanding and confidence with the technique.
Positive symptoms are a useful predictor of aggression in schizophrenia. Although a similar pattern of abnormal brain structures related to both positive symptoms and aggression has been reported, this observation has not yet been confirmed in a single sample.
To study the association between positive symptoms and aggression in schizophrenia on a neurobiological level, a prospective meta-analytic approach was employed to analyze harmonized structural neuroimaging data from 10 research centers worldwide. We analyzed brain MRI scans from 902 individuals with a primary diagnosis of schizophrenia and 952 healthy controls.
The result identified a widespread cortical thickness reduction in schizophrenia compared to their controls. Two separate meta-regression analyses revealed that a common pattern of reduced cortical gray matter thickness within the left lateral temporal lobe and right midcingulate cortex was significantly associated with both positive symptoms and aggression.
These findings suggested that positive symptoms such as formal thought disorder and auditory misperception, combined with cognitive impairments reflecting difficulties in deploying an adaptive control toward perceived threats, could escalate the likelihood of aggression in schizophrenia.
Structure and optical properties have been successfully determined for a series of niobium- and tantalum-containing layered alkaline-earth silicate compounds, Ba3(Nb6−xTax)Si4O26 (x = 0.6, 1.8, 3.0, 4.2, 5.4). The structure of this solid solution was found to be hexagonal P-62m (No. 189), with Z = 1. With x increases from 0.6 to 5.4, the lattice parameter a increases from 8.98804(8) to 9.00565(9) Å and c decreases from 7.83721(10) to 7.75212(12) Å. As a result, the volume decreases from 548.304(11) to 544.479(14) Å3. The (Nb/Ta)O6 distorted octahedra form continuous chains along the c-axis. These (Nb/Ta)O6 chains are in turn linked with the Si2O7 groups to form distorted pentagonal channels in which Ba ions were found. These Ba2+ ions have full occupancy and a 13-fold coordination environment with neighboring oxygen sites. Another salient feature of the structure is the linear Si–O–Si chains. When x in Ba3(Nb6−xTax)Si4O26 increases, the bond valence sum (BVS) values of the Ba sites increase slightly (2.09–2.20), indicating the size of the cage becoming progressively smaller (over-bonding). While SiO cages are also slightly smaller than ideal (BVS range from 4.16 to 4.19), the (Nb/Ta)O6 octahedral cages are slightly larger than ideal (BVS range from 4.87 to 4.90), giving rise to an under-bonding situation. The bandgaps of the solid solution members were measured between 3.39 and 3.59 eV, and the x = 3.0 member was modeled by density functional theory techniques to be 3.07 eV. The bandgaps of these materials indicate that they are potential candidates for ultraviolet photocatalyst.
Better understanding of interplay among symptoms, cognition and functioning in first-episode psychosis (FEP) is crucial to promoting functional recovery. Network analysis is a promising data-driven approach to elucidating complex interactions among psychopathological variables in psychosis, but has not been applied in FEP.
This study employed network analysis to examine inter-relationships among a wide array of variables encompassing psychopathology, premorbid and onset characteristics, cognition, subjective quality-of-life and psychosocial functioning in 323 adult FEP patients in Hong Kong. Graphical Least Absolute Shrinkage and Selection Operator (LASSO) combined with extended Bayesian information criterion (BIC) model selection was used for network construction. Importance of individual nodes in a generated network was quantified by centrality analyses.
Our results showed that amotivation played the most central role and had the strongest associations with other variables in the network, as indexed by node strength. Amotivation and diminished expression displayed differential relationships with other nodes, supporting the validity of two-factor negative symptom structure. Psychosocial functioning was most strongly connected with amotivation and was weakly linked to several other variables. Within cognitive domain, digit span demonstrated the highest centrality and was connected with most of the other cognitive variables. Exploratory analysis revealed no significant gender differences in network structure and global strength.
Our results suggest the pivotal role of amotivation in psychopathology network of FEP and indicate its critical association with psychosocial functioning. Further research is required to verify the clinical significance of diminished motivation on functional outcome in the early course of psychotic illness.
Major depressive disorder (MDD) represents a leading cause of disability. This study examines the course of disability in patients with chronic, recurrent and remitting MDD compared to healthy controls and identifies predictors of disability in remitting MDD.
We included 914 participants from the Netherlands Study of Depression and Anxiety (NESDA). DSM-IV MDD and WHO DAS II disability were assessed at baseline and at 2, 4 and 6 years. Six-year total and domain-specific disability were analysed and compared in participants with chronic (n = 57), recurrent (n = 120), remitting (n = 127) MDD and in healthy controls (n = 430). Predictors of residual disability were identified using linear regression analysis.
At baseline, most disability was found in chronic MDD, followed by recurrent MDD, remitting MDD and healthy controls. Across diagnostic groups, most disability was found in household activities, interpersonal functioning, participation in society and cognition. A chronic course was associated with chronic disability. Symptom remission was associated with a decrease in disability, but some disability remained. In remitting MDD, higher residual disability was predicted by older age, more severe avoidance symptoms, higher disability at baseline and late symptom remission. Severity of residual disability correlated with the severity of residual depressive symptoms.
Symptomatic remission is a prerequisite for improvements in disability. However, disability persists despite symptom remission. Therefore, treatment of MDD should include an explicit focus on disability, especially on the more complex domains. To this end, treatments should promote behavioural activation and address subthreshold depressive symptoms in patients with remitted MDD.
This paper introduces a new method to help designers assess the impact of changes to a product platform when introducing a new variant. The method evaluates a platform design by investigating how changing some components will impact other platform design perspectives such as material, function, manufacturing processes and assembly time. To assess the usefulness of this method, it was applied to assess platform changes resulting from successive generations of scanner heads from two manufacturers. The method indicated that one manufacturer improved their scanner head design by improving the functionality of its components and assembly time. Whereas, the other manufacturer's new scanner head used more material and manufacturing processes without benefiting other design perspectives. Compared to existing product family evaluation methods which focus only on maximising commonality between product variants, the proposed method considers potential platform design improvements and assesses them from multiple design perspectives before deciding on reusing existing components or implementing the new design. The information from this method will also complement existing commonality indices.