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Ureteroscopy is a minimally invasive surgical procedure for the removal of kidney stones. A ureteroscope, containing a hollow, cylindrical working channel, is inserted into the patient's kidney. The renal space proximal to the scope tip is irrigated, to clear stone particles and debris, with a saline solution that flows in through the working channel. We consider the fluid dynamics of irrigation fluid within the renal pelvis, resulting from the emerging jet through the working channel and return flow through an access sheath. Representing the renal pelvis as a two-dimensional rectangular cavity, we investigate the effects of flow rate and cavity size on flow structure and subsequent clearance time of debris. Fluid flow is modelled with the steady incompressible Navier–Stokes equations, with an imposed Poiseuille profile at the inlet boundary to model the jet of saline, and zero-stress conditions on the outlets. The resulting flow patterns in the cavity contain multiple vortical structures. We demonstrate the existence of multiple solutions dependent on the Reynolds number of the flow and the aspect ratio of the cavity using complementary numerical simulations and particle image velocimetry experiments. The clearance of an initial debris cloud is simulated via solutions to an advection–diffusion equation and we characterise the effects of the initial position of the debris cloud within the vortical flow and the Péclet number on clearance time. With only weak diffusion, debris that initiates within closed streamlines can become trapped. We discuss a flow manipulation strategy to extract debris from vortices and decrease washout time.
Adolescent dieting and disordered eating (DE) are risks for clinical eating disorders. In this five-wave longitudinal study, we tested gender-specific models linking early risk factors to temporal patterns of DE, considering appearance anxiety as a mediator. Participants were 384 Australian students (age 10 to 13; 45% boys) who reported their purging and skipping meals, experience with appearance-related teasing, media pressure, and appearance anxiety. Parents reported pubertal maturation and height/weight was measured. Gender differences in temporal patterns of DE were found and predictive models were tested using latent-variable growth curve and path models. Boys’ DE was generally stable over time; girls showed stability in purging but an average increase in skipping meals. Peer teasing, media pressure, and pubertal maturation were associated with more elevated initial DE in girls, and pubertal maturation was associated with a steeper increase in DE. For boys, body mass index had a direct positive association with DE. Appearance anxiety was associated with more DE, but there was only one significant indirect effect via anxiety, which was for boys’ pubertal maturation. Findings support the dominant role of social interactions and messages, as well as pubertal maturation, for girls’ DE and the prominence of physical risk factors for explaining boys’ DE.
It is clinically imperative to better understand the relationship between trauma, auditory hallucinations and dissociation. The personal narrative of trauma has enormous significance for each individual and is also important for the clinician, who must use this information to decide on a diagnosis and treatment approach.
To better understand whether dissociation contributes in a significant way to hallucinations in individuals with and without trauma histories.
Three groups of participants with auditory hallucinations were recruited, with diagnoses of: schizophrenia (without trauma) (n = 18), post-traumatic stress disorder (PTSD, n = 27) and comorbid schizophrenia and PTSD (SCZ+PTSD), n = 26). Clinician-administered measures included the PTSD Symptoms Scale Interview (PSSI-5), the Clinician-Administered Dissociative States Scale (CADSS) and the Psychotic Symptom Rating Scales (PSYRATS).
Dissociative symptoms were significantly higher in participants with trauma histories (PTSD and SCZ+PTSD groups) and significantly correlated with hallucinations in trauma-exposed participants, but not in participants with schizophrenia (without trauma history). Hallucination severity was correlated with the CADSS amnesia subscale score, but depersonalisation and derealisation were not.
Dissociation may be a mechanism in trauma-exposed individuals who hear voices, but it does not explain all hallucinatory experiences. The SCZ+PTSD group were in an intermediary position between schizophrenia and PTSD on dissociative and hallucination measures. The PTSD and SCZ+PTSD groups experienced dissociative phenomena much more frequently than the schizophrenia group, with a significant trend towards the amnesia subtype of dissociation.
The neuropsychological basis of first-rank symptoms in schizophrenia (FRS) is still a matter of debate. Three broad explanatory models for FRS have been proposed, each arising from a different perspective: (i) medial temporal lobes pathology (Trimble, 1990); (ii) reduced cerebral lateralisation and interhemispheric transfer (Crow, 1997); and (iii) deficits in self-monitoring of intentions due to prefrontal inhibitory dysfunction (Frith et al, 2000). The aim of the study was to test whether patients with FRS would show deficits consistent with the above models.
A broad range of neuropsychological tests were administered to patients with and without FRS and to healthy controls, comprising tests of verbal and nonverbal memory, measures of cerebral lateralisation and interhemispheric communication, tasks of executive functioning, as well as tests of general cognitive abilities.
On some cognitive tests, results were supportive of theories advocating reduced cerebral lateralisation and self-monitoring impairment. An unexpected finding was that, on many cognitive tasks, the performance of patients with FRS was better than that of patients without FRS, and not significantly different from that of controls. These results could not be accounted for by demographic features or medication effects.
The current study may be the most comprehensive examination of neuropsychological performance in patients with FRS to date. Our results suggest that broad cognitive impairment is not a necessary correlate of FRS.
This paper considers the significant role of cross-sectional geometry on resistance in co-axial pipe flows. We consider an axially flowing viscous fluid in between two long and thin elliptical coaxial cylinders, one inside the other. The outer cylinder is stationary, while the inner cylinder (rod) is free to move. The rod poses a resistance to the axial flow, while the viscous fluid poses a resistance to any motion of the rod. We show that the equations for flow in the axial direction – driven by a prescribed flux – and for flow within the cross-section of the domain – driven by the motion of the rod – decouple in the asymptotic limit of small cylinder aspect ratio into axial Poiseuille flow and transverse Stokes flow, respectively. The objective of this paper is to calculate numerically the axial and cross-sectional resistances and to determine their dependence on cross-sectional geometry – i.e. rod position and the ellipticities of the rod and bounding cylinder. We characterise axial resistance, first for three reduced parameter spaces that have not been fully analysed in the literature: (i) a circle in an ellipse, (ii) an ellipse in a circle and (iii) an ellipse in an ellipse of equal eccentricity and orientation, before extending our geometric parameter space to determine the overall optimal geometry to minimise axial flow resistance for fixed cross-sectional area. Cross-sectional resistance is characterised via coefficients in a Stokes resistance matrix and we highlight the interdependent effects of cross-sectional ellipticity and boundary interactions.
On the northern side of the Cathedral of Santa Maria Assunta in Como stands a monumental entrance carved in 1507 by the brothers Giacomo and Tommaso Rodari (Fig. 210).1 A highlight of their work on the Cathedral, which began around 1484, this portal – known as the Porta della Rana after a frog carved on the door jamb – features a central tympanum with a sculpted Visitation supported by pilasters decorated with candelabra in low relief flanked by four statues of saints set in niches. At the top stands an aedicule buttressed by two scrolls with a statue of the Virgin framed by angels and surmounted by the figure of God the Father in a mandorla. Flanking the entryway are two heavily ornamented, freestanding columns, composed of chromatically varied blocks of stone decorated with an extraordinary variety of sculpture. The right-hand column (Fig. 211), for example, stands on a plinth with reliefs depicting Hercules battling a centaur and Mars with Victory. On top of this sit four lions that support a cylindrical altar with putti holding grotesque heads. Next there is a round column base, on which is a bulbous vessel covered in leaves and decorated with hanging garlands and handled tablets (tabula ansata) inscribed in Latin with Christian dictums. This then supports a divider with an inset banderole, an altar with swags and eagles, and another one with swags and dolphins. Moving upward, stacked atop this is a section adorned with scrolls and shells, an upside-down bulb decorated with leaves and swags, a beaded garland, a vase partially in the form of a basket, and a laurel wreath. Finally, at the summit of this towering architectural element is a Corinthian-esque column, the shaft of which is divided by a band decorated with putti and the head of a Roman emperor. The other column features the same component parts, but each is carved with subtly different motifs.
Forty years ago, Knut Fladmark (1979) argued that the Pacific Coast offered a viable alternative to the ice-free corridor model for the initial peopling of the Americas—one of the first to support a “coastal migration theory” that remained marginal for decades. Today, the pre-Clovis occupation at the Monte Verde site is widely accepted, several other pre-Clovis sites are well documented, investigations of terminal Pleistocene subaerial and submerged Pacific Coast landscapes have increased, and multiple lines of evidence are helping decode the nature of early human dispersals into the Americas. Misconceptions remain, however, about the state of knowledge, productivity, and deglaciation chronology of Pleistocene coastlines and possible technological connections around the Pacific Rim. We review current evidence for several significant clusters of early Pacific Coast archaeological sites in North and South America that include sites as old or older than Clovis. We argue that stemmed points, foliate points, and crescents (lunates) found around the Pacific Rim may corroborate genomic studies that support an early Pacific Coast dispersal route into the Americas. Still, much remains to be learned about the Pleistocene colonization of the Americas, and multiple working hypotheses are warranted.
To describe and quantify the magnitude and distribution of stunting, wasting, anaemia, overweight and obesity by wealth, level of education and ethnicity in Ecuador.
We used nationally representative data from the 2012 Ecuadorian National Health and Nutrition Survey. We used the Multidimensional Poverty Index (MPI) as a proxy of wealth. The MPI identifies deprivations across three dimensions (health, education and standard of living). We defined education by years of schooling and ethnicity as a social construct, based on shared social, cultural and historical experiences, using Ecuadorian census categories.
Urban and rural Ecuador, including the Amazon rainforest and the Galapagos Islands.
Children aged <5 years (n 8580), adolescent women aged 11–19 years (n 4043) and adult women aged 20–49 years (n 15 203).
Among children <5 years, stunting and anaemia disproportionately affected low-wealth, low-education and indigenous groups. Among adolescent and adult women, higher rates of stunting, overweight and obesity were observed in the low-education and low-wealth groups. Stunting and short stature rates were higher in indigenous women, whereas overweight and obesity rates were higher in Afro-Ecuadorian women.
Malnutrition differs significantly across sociodemographic groups, disproportionately affecting those in the low wealth tertile and ethnic minorities. Rates of stunting remain high compared with other countries in the region with similar economic development. The effective implementation of double-duty actions with the potential to impact both sides of the double burden is urgently required.
Introduction: Optimizing naloxone dosing in the context of increasing fentanyl and ultra-potent opioid (UPO) prevalence is an important consideration for emergency health care providers. The goal of this systematic review was to evaluate the association between initial and cumulative naloxone doses on effective reversal and adverse events in undifferentiated and fentanyl/UPO overdoses. Methods: We searched Embase, MEDLINE, Cochrane Central Register of Controlled Trials, DARE, CINAHL, Science Citation Index, reference lists, toxicology websites, and conference proceedings from July to October 2018 and back to 1972. Our search included pertinent indexing terms for UPOs. We included interventional and observational studies reporting on naloxone administration for opioid toxicity reversal in people ≥12 years old. Additionally, we accessed non-traditional evidence sources (case reports and series) given this rapidly changing field. We conducted inclusion screens, data extraction and quality assessments in duplicate. We summarized study characteristics and where reported, analyzed number of patients with clinical response. Response was defined as not receiving further naloxone doses and remaining alive. Results: We included 174 studies (108 case reports and series, 55 observational, 9 interventional) with 26,660 subjects (median age 35.1; 74.2% male). We observed lower response among patients exposed to fentanyl/UPO versus heroin for initial naloxone doses ≤0.4mg (56.8% versus 80.2%) and > 0.4mg (27.0% versus 82.1%). Mean cumulative doses were higher for fentanyl/UPO (2.10 mg, SD 1.80 mg) versus heroin (1.48 mg, SD 1.68 mg) overdoses. In North American studies the median cumulative dose used was higher for fentanyl/UPO versus heroin overdoses. A dose-response curve for fentanyl/UPO studies showed marked variability in doses among responders, indicating heterogeneity. Adverse events reporting was inconsistent; 10% of subjects experienced withdrawal based on studies in which they were reported. Conclusion: This is the first systematic review to summarize proportion of patients with clinical response by naloxone dose provided. While variable reporting, study quality, heterogeneity, and our outcome definitions limit the conclusions we can draw, it appears that higher initial doses and in some cases, higher cumulative naloxone doses were used and may be necessary to reverse toxicity due to fentanyl/UPO compared to other opioids. High-quality prospective studies assessing effectiveness and safety are needed.
Introduction: Increasing opioid prescribing has been linked to an epidemic of opioid misuse. Our objective was to synthesize available evidence about patient-, prescriber-, medication-, and system-level risk factors for developing opioid misuse from prescribed opioids among patients presenting with pain unrelated to cancer. Our hypothesis was that we would identify risk factors predisposing patients to developing opioid misuse. Methods: We developed a systematic search strategy and applied it to nine electronic reference databases and six clinical trial registries. We hand searched related journals and conference proceedings, the reference lists of included studies, and the top 100 hits on Google. We included studies where a medical professional exposed adults or children to an opioid through a prescription. We excluded studies with over 50% cancer patients, palliative patients, and those with illicit opioid initiation. Two reviewers independently reviewed titles, abstracts, and full texts, and extracted data using standardized forms. We assessed study quality using risk of bias. We synthesized effect sizes of dichotomous risk factors on opioid misuse using inverse variance random-effects meta-analysis, and the inverse variance-weighted mean difference between opioid misusers and non-misusers for continuously measured factors. We conducted an a priori defined subgroup analysis among opioid-naïve patients. Results: Among 9,629 studies, 67 met our inclusion criteria. Among those who had been prescribed outpatient opioids, the following factors were associated with the development of misuse: a prior history of illicit drug use (OR: 4.21, 95% CI: 2.31-7.65), recent benzodiazepine use (OR: 2.57, 95% CI: 1.23-5.38), any mental health diagnosis (OR: 2.45, 95% CI: 1.91-3.15), any short acting (IR) opioid prescription (OR: 2.40, 95% CI: 1.15-5.02), younger age (OR: 2.19, 95%CI: 1.81-2.64), and male sex (OR: 1.23, 95% CI: 1.10-1.36). Among studies limiting their population to opioid-naïve patients, younger age was the most significant risk factor for opioid misuse (OR: 5.42, 95% CI:1.51-19.43). Conclusion: Of the risk factors examined, non-cancer pain patients with a prior history of substance use or mental health diagnoses were at highest risk for prescription opioid misuse. Younger opioid-naïve patients were at highest risk of misuse. Clinicians should consider these risk factors when managing acute pain in the emergency department.
Tissue engineering aims to grow artificial tissues in vitro to replace those in the body that have been damaged through age, trauma or disease. A recent approach to engineer artificial cartilage involves seeding cells within a scaffold consisting of an interconnected 3D-printed lattice of polymer fibres combined with a cast or printed hydrogel, and subjecting the construct (cell-seeded scaffold) to an applied load in a bioreactor. A key question is to understand how the applied load is distributed throughout the construct. To address this, we employ homogenisation theory to derive equations governing the effective macroscale material properties of a periodic, elastic–poroelastic composite. We treat the fibres as a linear elastic material and the hydrogel as a poroelastic material, and exploit the disparate length scales (small inter-fibre spacing compared with construct dimensions) to derive macroscale equations governing the response of the composite to an applied load. This homogenised description reflects the orthotropic nature of the composite. To validate the model, solutions from finite element simulations of the macroscale, homogenised equations are compared to experimental data describing the unconfined compression of the fibre-reinforced hydrogels. The model is used to derive the bulk mechanical properties of a cylindrical construct of the composite material for a range of fibre spacings and to determine the local mechanical environment experienced by cells embedded within the construct.
We present ALMA band 7 data of the extreme OH/IR star, OH 26.5+0.6. In addition to lines of CO and its isotopologues, the circumstellar envelope also exhibits a number of emission lines due to metal-containing molecules, e.g., NaCl and KCl. A lack of C18O is expected, but a non-detection of C17O is puzzling given the strengths of H217O in Herschel spectra of the star. However, a line associated with Si17O is detected. We also report a tentative detection of a gas-phase emission line of MgS. The ALMA spectrum of this object reveals intriguing features which may be used to investigate chemical processes and dust formation during a high mass-loss phase.
Karen A Waters, The Children's Hospital at Westmead and The University of Sydney, Camperdown, NSW, Australia,
Nicholas J Hunt, The University of Sydney, Camperdown, NSW, Australia,
Rita MacHaalani, The University of Sydney, Camperdown, NSW, Australia
Since deaths attributed to sudden infant death syndrome (SIDS) occur during sleep, failure to arouse in a stressful situation comprises one component in the proposed mechanism of death. While the infant was previously apparently healthy, the hypothesis underpinning neuropathological studies is that an underlying defect in the infant's brain has contributed to death. The defect in infants who do not arouse may be developmental, inherited, or secondary to previous non-fatal insults. The brainstem and hypothalamus are two regions housing nuclei with important roles in stress responses and arousal mechanisms. This chapter focuses on studies of the hypothalamus and how deficits in this region may contribute to SIDS.
The hypothalamus is a small but complex part of the brain with important roles in the homeostasis of energy balance, circadian rhythms, and stress responses, as well as growth and reproductive behaviors (1). As a regulatory center for so many functions, it receives input from, and transmits output to, a large number of other brain regions. Thus, as the hypothalamus controls many physiological functions, and is highly interconnected with other brain regions, it is an excellent candidate for abnormalities contributing to the pathogenesis of SIDS.
The hypothalamus was evaluated early in the 1990s in SIDS infants (2, 3). At that time, fewer neurotransmitters had been identified compared to today. But even without our current understanding (e.g. of the orexins which were discovered in 1998), the hypothalamus was of interest in SIDS because of its known role in the regulation of sleep. Findings at that time included increased tryptophan content and decreased serotonin, increased serotonin receptor binding, and increased monoamine oxidase-A (MOA) activity, with decreased choline acetyltransferase (ChAT) activity (2) (see Table 28.1).
Updating our knowledge of the hypothalamus and its potential role in SIDS is important, because our understanding of the hypothalamus is now more sophisticated with regards to its structure, functions, and development (1). In addition, a series of recent studies have made important advances in our understanding of abnormalities in the hypothalamus of SIDS infants.
Auditory hallucinations (AH) are often considered a sign of a psychotic disorder. This is promoted by the DSM-5 category of Other Specified Schizophrenia Spectrum And Other Psychotic Disorder (OSSSOPD), the diagnostic criteria for which are fulfilled with the sole presence of persistent AH, in the absence of any other psychotic symptoms. And yet, persistent AH are not synonymous with having a psychotic disorder, and should therefore not be uncritically treated as such. Many people who seek treatment for persistent AH have no other psychotic symptoms, have preserved reality-testing capacities, and will never develop a schizophrenia spectrum disorder. Instead, hallucinations may be the result of many different causes, including borderline personality disorder, post-traumatic stress disorder (PTSD), hearing loss, sleep disorders or brain lesions, and they may even occur outside the context of any demonstrable pathology. In such cases, the usage of the DSM-5 diagnosis of OSSSOPD would be incorrect, and it may prompt unwarranted treatment with antipsychotic medication. We therefore argue that a DSM-5 diagnosis of Schizophrenia Spectrum Disorder (or any other type of psychotic disorder) characterized by AH should require at least one more symptom listed under the A-criterion (i.e. delusions, disorganized speech, disorganized or catatonic behavior or negative symptoms). Adhering to these more stringent criteria may help to distinguish between individuals with persistent AH which are part of a psychotic disorder, for whom antipsychotic medication may be helpful, and individuals with AH in the absence of such a disorder who may benefit from other approaches (e.g. different pharmacological interventions, improving coping style, trauma-related therapy).
Adolescents’ appearance-related concerns can provoke increasing emotional, social, and eating-related problems. The aims of this five-wave (2.5-year), multiple-informant longitudinal study were to (a) examine growth trajectories of appearance anxiety symptoms and appearance esteem, (b) identify whether trajectories differed by gender, and (c) examine several launching factors including parent-reported physical maturation, peer-rated physical appearance, body mass index, and appearance teasing by parents and peers. Participants were 387 adolescents (44% boys) aged 10 to 13 years at the first assessment. Steep growth in appearance anxiety symptoms was found for both girls and boys, but there was no average change in appearance esteem. Girls had more elevated appearance anxiety symptoms and lower appearance esteem than boys, girls’ body mass index was associated with symptoms, and earlier physical maturation and teasing about appearance, alone and in combination, were associated with growth in appearance anxiety symptoms for girls and boys. Earlier maturing boys who were highly teased by parents, but even more so when teased by peers, were at utmost risk for elevated appearance anxiety symptoms and increasing symptoms over time. In contrast, all girls exhibited elevated or increasing appearance anxiety symptoms across time, with the exception of girls with the latest maturation who also reported little teasing about their appearance.
The development of an economic capital model requires a decision to be made regarding how to aggregate capital requirements for the individual risk factors while taking into account the effects of diversification. Under the Individual Capital Adequacy Standards framework, UK life insurers have commonly adopted a correlation matrix approach due to its simplicity and ease in communication to the stakeholders involved, adjusting the result, where appropriate, to allow for non-linear interactions. The regulatory requirements of Solvency II have been one of the principal drivers leading to an increased use of more sophisticated aggregation techniques in economic capital models. This paper focusses on a simulation-based approach to the aggregation of capital requirements using copulas and proxy models. It describes the practical challenges in parameterising a copula including how allowance may be made for tail dependence. It also covers the challenges associated with fitting and validating a proxy model. In particular, the paper outlines how insurers could test, communicate and justify the choices made through the use of some examples.
The provision of prescribed vitamin D to all aged-care residents has been implemented in New Zealand as part of a government-led falls prevention programme. To our knowledge, there has been no evaluation of this universal programme on vitamin D status and functional and health outcomes. Thus, we aimed to determine 25-hydroxyvitamin D (25(OH)D) concentrations and their predictors in aged-care residents across the country and to investigate whether the government-funded programme was associated with adequate vitamin D status.
Cross-sectional survey of sociodemographic, biochemical, anthropometric, dietary and health characteristics. Blood samples were analysed for serum 25(OH)D and other biochemical measures. Multiple regression was used to examine predictors of vitamin D status.
Sixteen residential aged-care facilities throughout New Zealand.
Residents aged ≥60 years with residency duration >12 weeks (n 309).
Mean serum 25(OH)D was 89·9 (95 % CI 85·2, 94·5) nmol/l and monthly supplements (1250 µg (50 000 IU)) were taken by 75 % of all residents. Of those not taking a funded supplement, 65·3 % had serum 25(OH)D <50 nmol/l compared with only 1·5 % of supplement users. Being female, residing at lower latitude, increasing duration of aged-care residency and raised serum α1-acid glycoprotein were positively associated with higher 25(OH)D concentrations. Supplemental vitamin D from all sources was the strongest predictor, increasing serum 25(OH)D levels by more than 70 nmol/l. Furthermore, 25 % of participants had serum 25(OH)D levels >125 nmol/l.
Residents taking supplemental vitamin D had adequate vitamin D status; however monitoring of long-term supplementation should be considered, due to the high proportion of participants with high serum 25(OH)D levels.