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This text is geared toward students who have an undergraduate degree or extensive coursework in engineering or the physical sciences and who wish to develop their understanding of the essential topics of applied mathematics. The methods covered in the chapters form the core of analysis in engineering and the physical sciences. Readers will learn the solutions, techniques, and approaches that they will use as academic researchers or industrial R&D specialists. For example, they will be able to understand the fundamentals behind the various scientific software packages that are used to solve technical problems (such as the equations describing the solid mechanics of complex structures or the fluid mechanics of short-term weather prediction and long-term climate change), which is crucial to working with such codes successfully. Detailed and numerous worked problems help to ensure a clear and well-paced introduction to applied mathematics. Computational challenge problems at the end of each chapter provide students with the opportunity for hands-on learning and help to ensure mastery of the concepts. Adaptable to one- and two-semester courses.
Two new species, Begonia bracteolata and Begonia keralensis, are described from the Western Ghats of India. They are placed in the newly created Begonia sect. Flocciferae, along with B. albo-coccinea Hook. and B. floccifera Bedd. Lectotypes are designated for three names within this section. Colour photoplates, illustrations and an identification key to Begonia sect. Flocciferae are also provided.
There is no single ultrasound probe available that allows visualization of all airway structures in children of all ages. In larger children above approximately 8 years of age, the linear medium-to-high frequency (5–14 MHz) transducer is suitable for imaging superficial airway structures (within 0–5 cm beneath the skin surface). The curved low-frequency transducer (~4.0 MHz) is most suitable for obtaining sagittal and parasagittal views of the tongue and structures in the submandibular and supraglottic regions, mainly because of its wider field of view. Linear transducers, which are used for assessment of the upper airways, provide excellent images of superficial structures, such as ribs and the pleura, but deeper structures can be difficult to assess. A micro-convex transducer (~8.0 MHz) is a good all-round transducer for focused ultrasonographic examination of the lungs, since most micro-convex transducers have an acceptable image quality of both superficial (pleura) and deeper structures (e.g., lung consolidation, atelectasis). Furthermore, micro-convex transducers are often small, which makes it easier to access the posterior thoracic wall, when the patient can only be examined in the supine position. An alternative to the micro-convex transducer for examination of the lungs is the curved low-frequency transducer (~4.0 MHz), which also has an acceptable image quality of both superficial and deeper structures. Since visualization of superficial and deep structures is needed, it is important to continuously optimize transducer frequency to obtain the best possible images. The presence or absence of artifacts are an important part of lung ultrasonography; hence, one should be mindful to deactivate any image optimization software that is inherently built into newer ultrasound machines as this would remove or diminish the presence of these useful artifacts when performing lung ultrasonography.
Some of the greatest successes in infectious disease control rest on empirically grounded models of human and livestock infections. In contrast, disease control in wildlife has not always been as successful. Timely translation of knowledge into proposed management actions remains a challenge in several wildlife disease systems, one of which is pneumonia management in bighorn sheep throughout the North American West. Although pneumonia was recognised as a major impediment to bighorn sheep conservation >80 years ago, a series of challenges stymied the management decision-making process. Despite past obstacles, recent advances from long-term, intensive studies of marked individual sheep have motivated new interest in research-driven strategies for disease management in this system. The system provides an unusual opportunity to study an emerging pathogen disproportionately impacting immature animals through infections that originate from asymptomatically infected adult hosts. We tell the story of bighorn sheep pneumonia, emphasising the obstacles that historically hindered decision-making, the biological or logistical constraints underlying each decision point, and the particular empirical insights that clarified each constraint.
Healthcare-associated bloodstream infections (HABSIs) are a significant cause of mortality and morbidity in the neonatal intensive care unit (NICU) population. Our objectives were to review the epidemiology of HABSIs in our NICU and to examine the applicability of National Healthcare Safety Network (NHSN) definitions to the NICU population.
We performed a retrospective review of all neonates admitted to the 54-bed, level IV NICU at Yale-New Haven Children’s Hospital with a HABSI between January 1, 2013, and December 31, 2018. Clinical definitions per NICU team and NHSN site-specific definitions used for source identification were compared using the McNemar χ2 test.
We identified 86 HABSIs with an incidence rate of 0.80 per 1,000 patient days. Only 13% of these were CLABSIs. Both CLABSIs and non–catheter-related bloodstream infections occurred primarily in preterm neonates, but the latter were associated with a significantly higher incidence of comorbidities and the need for respiratory support. The NHSN definitions were less likely to identify a source compared to the clinical definitions agreed upon by our NICU treating team (P < .001). Furthermore, 50% of patients without an identified source of infection by NHSN definitions were bacteremic with a mucosal barrier injury organism, likely from gut translocation.
HABSIs occur primarily in premature infants with comorbidities, and CLABSIs account for a small proportion of these infections. With the increasing focus on HABSI prevention, there is a need for better NHSN site-specific definitions for the NICU population to prevent misclassification and direct prevention efforts.
Iraq and Afghanistan Veterans with posttraumatic stress disorder (PTSD) and traumatic brain injury (TBI) history have high rates of performance validity test (PVT) failure. The study aimed to determine whether those with scores in the invalid versus valid range on PVTs show similar benefit from psychotherapy and if psychotherapy improves PVT performance.
Veterans (N = 100) with PTSD, mild-to-moderate TBI history, and cognitive complaints underwent neuropsychological testing at baseline, post-treatment, and 3-month post-treatment. Veterans were randomly assigned to cognitive processing therapy (CPT) or a novel hybrid intervention integrating CPT with TBI psychoeducation and cognitive rehabilitation strategies from Cognitive Symptom Management and Rehabilitation Therapy (CogSMART). Performance below standard cutoffs on any PVT trial across three different PVT measures was considered invalid (PVT-Fail), whereas performance above cutoffs on all measures was considered valid (PVT-Pass).
Although both PVT groups exhibited clinically significant improvement in PTSD symptoms, the PVT-Pass group demonstrated greater symptom reduction than the PVT-Fail group. Measures of post-concussive and depressive symptoms improved to a similar degree across groups. Treatment condition did not moderate these results. Rate of valid test performance increased from baseline to follow-up across conditions, with a stronger effect in the SMART-CPT compared to CPT condition.
Both PVT groups experienced improved psychological symptoms following treatment. Veterans who failed PVTs at baseline demonstrated better test engagement following treatment, resulting in higher rates of valid PVTs at follow-up. Veterans with invalid PVTs should be enrolled in trauma-focused treatment and may benefit from neuropsychological assessment after, rather than before, treatment.
Psychologists have identified multiple different forms of conflict, such as information processing conflict and goal conflict. As such, there is a need to examine the similarities and differences in neurology between each form of conflict. To address this, we conducted a comprehensive electroencephalogram (EEG) analysis of Shadli, Glue, McIntosh, and McNaughton’s calibrated stop-signal task (SST) goal-conflict task. Specifically, we examined changes in scalp-wide current source density (CSD) power and coherence across a wide range of frequency bands during the calibrated SST (n = 34). We assessed differences in EEG between the high and low goal-conflict conditions using hierarchical analyses of variance (ANOVAs). We also related goal-conflict EEG to trait anxiety, neuroticism, Behavioural Inhibition System (BIS)-anxiety and revised BIS (rBIS) using regression analyses. We found that changes in CSD power during goal conflict were limited to increased midfrontocentral theta. Conversely, coherence increased across 23 scalp-wide theta region pairs and one frontal delta region pair. Finally, scalp-wide theta significantly predicted trait neuroticism but not trait anxiety, BIS-anxiety or rBIS. We conclude that goal conflict involves increased midfrontocentral CSD theta power and scalp-wide theta-dominated coherence. Therefore, compared with information processing conflict, goal conflict displays a similar EEG power profile of midfrontocentral theta but a much wider coherence profile. Furthermore, the increases in theta during goal conflict are the characteristic of BIS-driven activity. Therefore, future research should confirm whether these goal-conflict effects are driven by the BIS by examining whether the effects are attenuated by anxiolytic drugs. Overall, we have identified a unique network of goal-conflict EEG during the calibrated SST.
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.
Disordered gambling (DG) is a rare but serious condition that results in considerable financial and interpersonal harms. Twin studies indicate that DG is heritable but are silent with respect to specific genes or pathways involved. Existing genomewide association studies (GWAS) of DG have been substantially underpowered. Larger GWAS of other psychiatric disorders now permit calculation of polygenic risk scores (PRSs) that reflect the aggregated effects of common genetic variants contributing risk for the target condition. The current study investigated whether gambling and DG are associated with PRSs for four psychiatric conditions found to be comorbid with DG in epidemiologic surveys: major depressive disorder (MDD), attention-deficit hyperactivity disorder (ADHD), bipolar disorder (BD) and schizophrenia (SCZ). Genotype data and survey responses were analyzed from the Wave IV assessment (conducted in 2008) of the National Longitudinal Study of Adolescent to Adult Health, a representative sample of adolescents recruited in 1994–1995 and followed into adulthood. Among participants classified as having European ancestry based on genetic analysis (N = 5215), 78.4% reported ever having gambled, and 1.3% reported lifetime DG. Polygenic risk for BD was associated with decreased odds of lifetime gambling, OR = 0.93 [0.87, 0.99], p = .045, pseudo-R2(%) = .12. The SCZ PRS was associated with increased odds of DG, OR = 1.54 [1.07, 2.21], p = .02, pseudo-R2(%) = .85. Polygenic risk scores for MDD and ADHD were not related to either gambling outcome. Investigating features common to both SCZ and DG might generate valuable clues about the genetically influenced liabilities to DG.
We performed systematic review on 40 paired hospital and nursing home charts from a clinical trial to evaluate the fidelity of transitions of care among those discharged on antibiotics. We found that 30% of transitions included an inappropriate change to the patient’s antibiotic plan of care.
The Twins Early Development Study (TEDS) is a longitudinal twin study that recruited over 16,000 twin-pairs born between 1994 and 1996 in England and Wales through national birth records. More than 10,000 of these families are still engaged in the study. TEDS was and still is a representative sample of the population in England and Wales. Rich cognitive and emotional/behavioral data have been collected from the twins from infancy to emerging adulthood, with data collection at first contact and at ages 2, 3, 4, 7, 8, 9, 10, 12, 14, 16, 18 and 21, enabling longitudinal genetically sensitive analyses. Data have been collected from the twins themselves, from their parents and teachers, and from the UK National Pupil Database. Genotyped DNA data are available for 10,346 individuals (who are unrelated except for 3320 dizygotic co-twins). TEDS data have contributed to over 400 scientific papers involving more than 140 researchers in 50 research institutions. TEDS offers an outstanding resource for investigating cognitive and behavioral development across childhood and early adulthood and actively fosters scientific collaborations.
In January of 2010, North Carolina (NC) USA implemented state-wide Trauma Triage Destination Plans (TTDPs) to provide standardized guidelines for Emergency Medical Services (EMS) decision making. No study exists to evaluate whether triage behavior has changed for geriatric trauma patients.
The impact of the NC TTDPs was investigated on EMS triage of geriatric trauma patients meeting physiologic criteria of serious injury, primarily based on whether these patients were transported to a trauma center.
This is a retrospective cohort study of geriatric trauma patients transported by EMS from March 1, 2009 through September 30, 2009 (pre-TTDP) and March 1, 2010 through September 30, 2010 (post-TTDP) meeting the following inclusion criteria: (1) age 50 years or older; (2) transported to a hospital by NC EMS; (3) experienced an injury; and (4) meeting one or more of the NC TTDP’s physiologic criteria for trauma (n = 5,345). Data were obtained from the Prehospital Medical Information System (PreMIS). Data collected included proportions of patients transported to a trauma center categorized by specific physiologic criteria, age category, and distance from a trauma center.
The proportion of patients transported to a trauma center pre-TTDP (24.4% [95% CI 22.7%-26.1%]; n = 604) was similar to the proportion post-TTDP (24.4% [95% CI 22.9%-26.0%]; n = 700). For patients meeting specific physiologic triage criteria, the proportions of patients transported to a trauma center were also similar pre- and post-TTDP: systolic blood pressure <90 mmHg (22.5% versus 23.5%); respiratory rate <10 or >29 (23.2% versus 22.6%); and Glascow Coma Scale (GCS) score <13 (26.0% versus 26.4%). Patients aged 80 years or older were less likely to be transported to a trauma center than younger patients in both the pre- and post-TTDP periods.
State-wide implementation of a TTDP had no discernible effect on the proportion of patients 50 years and older transported to a trauma center. Under-triage remained common and became increasingly prevalent among the oldest adults. Research to understand the uptake of guidelines and protocols into EMS practice is critical to improving care for older adults in the prehospital environment.
In the present study, we aimed to compare anthropometric indicators as predictors of mortality in a community-based setting.
We conducted a population-based longitudinal study nested in a cluster-randomized trial. We assessed weight, height and mid-upper arm circumference (MUAC) on children 12 months after the trial began and used the trial’s annual census and monitoring visits to assess mortality over 2 years.
Children aged 6–60 months during the study.
Of 1023 children included in the study at baseline, height-for-age Z-score, weight-for-age Z-score, weight-for-height Z-score and MUAC classified 777 (76·0 %), 630 (61·6 %), 131 (12·9 %) and eighty (7·8 %) children as moderately to severely malnourished, respectively. Over the 2-year study period, fifty-eight children (5·7 %) died. MUAC had the greatest AUC (0·68, 95 % CI 0·61, 0·75) and had the strongest association with mortality in this sample (hazard ratio = 2·21, 95 % CI 1·26, 3·89, P = 0·006).
MUAC appears to be a better predictor of mortality than other anthropometric indicators in this community-based, high-malnutrition setting in Niger.
Metabolic syndrome (MetS) is associated with reduced life expectancy in patients with affective disorders, however, whether MetS also plays a role before the onset of affective disorder is unknown. We aimed to investigate whether MetS, inflammatory markers or oxidative stress act as risk factors for affective disorders, and whether MetS is associated with increased inflammation and oxidative stress.
We conducted a high-risk study including 204 monozygotic (MZ) twins with unipolar or bipolar disorder in remission or partial remission (affected), their unaffected co-twins (high-risk) and twins with no personal or family history of affective disorder (low-risk). Metabolic Syndrome was ascertained according to the International Diabetes Federation (IDF) criteria. Inflammatory markers and markers of oxidative stress were analyzed from fasting blood and urine samples, respectively.
The affected and the high-risk group had a significantly higher prevalence of MetS compared to the low-risk group (20% v. 15% v. 2.5%, p = 0.0006), even after adjusting for sex, age, smoking and alcohol consumption. No differences in inflammatory and oxidative markers were seen between the three groups. Further, MetS was associated with alterations in inflammatory markers, and oxidative stress was modestly correlated with inflammation.
Metabolic syndrome is associated with low-grade inflammation and may act as a risk factor and a trait marker for affective disorders. If confirmed in longitudinal studies, this suggests the importance of early intervention and preventive approaches targeted towards unhealthy lifestyle factors that may contribute to later psychopathology.
This study originated in collaboration with Thomas Dishion because of concerns that a group format for aggressive children might dampen the effects of cognitive-behavioral intervention. Three hundred sixty aggressive preadolescent children were screened through teacher and parent ratings. Schools were randomized to receive either an individual or a group format of the child component of the same evidence-based program. The results indicate that there is variability in how group-based cognitive-behavioral intervention can affect aggressive children through a long 4-year follow-up after the end of the intervention. Aggressive children who have higher skin conductance reactivity (potentially an indicator of poorer emotion regulation) and who have a variant of the oxytocin receptor gene that may be associated with being hyperinvolved in social bonding have better outcomes in their teacher-rated externalizing behavior outcomes over time if they were seen individually rather than in groups. Analyses also indicated that higher levels of the group leaders’ clinical skills predicted reduced externalizing behavior problems. Implications for group versus individual format of cognitive-behavioral interventions for aggressive children, and for intensive training for group therapists, informed by these results, are discussed.
We designed two practical, user-friendly, low-cost, aesthetically pleasing resources, with the goal of introducing residents and observers to a new Competence by Design assessment system based on entrustable professional activities. They included a set of rotation- and stage-specific entrustable professional activities reference cards for bedside use by residents and observers and a curriculum board to organize the entrustable professional activities reference cards by stages of training based on our program's curriculum map. A survey of 14 emergency medicine residents evaluated the utilization and helpfulness of these resources. They had a positive impact on our program's transition to Competence by Design and could be successfully incorporated into other residency programs to support the introduction of entrustable professional activities-based Competence by Design assessment systems.
The major facilitator superfamily domain 2a protein was identified recently as a lysophosphatidylcholine (LPC) symporter with high affinity for LPC species enriched with DHA (LPC-DHA). To test the hypothesis that reproductive state and choline intake influence plasma LPC-DHA, we performed a post hoc analysis of samples available through 10 weeks of a previously conducted feeding study, which provided two doses of choline (480 and 930 mg/d) to non-pregnant (n 21), third-trimester pregnant (n 26), and lactating (n 24) women; all participants consumed 200 mg of supplemental DHA and 22 % of their daily choline intake as 2H-labelled choline. The effects of reproductive state and choline intake on total LPC-DHA (expressed as a percentage of LPC) and plasma enrichments of labelled LPC and LPC-DHA were assessed using mixed and generalised linear models. Reproductive state interacted with time (P = 0·001) to influence total LPC-DHA, which significantly increased by week 10 in non-pregnant women, but not in pregnant or lactating women. Contrary to total LPC-DHA, patterns of labelled LPC-DHA enrichments were discordant between pregnant and lactating women (P < 0·05), suggestive of unique, reproductive state-specific mechanisms that result in reduced production and/or enhanced clearance of LPC-DHA during pregnancy and lactation. Regardless of the reproductive state, women consuming 930 v. 480 mg choline per d exhibited no change in total LPC-DHA but higher d3-LPC-DHA (P = 0·02), indicating that higher choline intakes favour the production of LPC-DHA from the phosphatidylethanolamine N-methyltransferase pathway of phosphatidylcholine biosynthesis. Our results warrant further investigation into the effect of reproductive state and dietary choline on LPC-DHA dynamics and its contribution to DHA status.