Tag: nevin manimala

Proc Lond Math Soc. 2023 Jan;126(1):334-389. doi: 10.1112/plms.12493. Epub 2022 Oct 26.

ABSTRACT

We consider the nonlinear Schrödinger equation on the half-line $x⩾0$ with a Robin boundary condition at $x=0$ and with initial data in the weighted Sobolev space $H^{1,1}\left(R_{+}\right)$ . We prove that there exists a global weak solution of this initial-boundary value problem and provide a representation for the solution in terms of the solution of a Riemann-Hilbert problem. Using this representation, we obtain asymptotic formulas for the long-time behavior of the solution. In particular, by restricting our asymptotic result to solutions whose initial data are close to the initial profile of the stationary one-soliton, we obtain results on the asymptotic stability of the stationary one-soliton under any small perturbation in $H^{1,1}\left(R_{+}\right)$ . In the focusing case, such a result was already established by Deift and Park using different methods, and our work provides an alternative approach to obtain such results. We treat both the focusing and the defocusing versions of the equation.

PMID:37067878 | PMC:PMC10091827 | DOI:10.1112/plms.12493

J Raman Spectrosc. 2022 Dec;53(12):2044-2057. doi: 10.1002/jrs.6447. Epub 2022 Sep 12.

ABSTRACT

Surface-enhanced Raman spectroscopy (SERS) has wide diagnostic applications because of narrow spectral features that allow multiplexed analysis. Machine learning (ML) has been used for non-dye-labeled SERS spectra but has not been applied to SERS dye-labeled materials with known spectral shapes. Here, we compare the performances of spectral decomposition, support vector regression, random forest regression, partial least squares regression, and convolutional neural network (CNN) for SERS “spectral unmixing” from a multiplexed mixture of 7 SERS-active “nanorattles” loaded with different dyes for mRNA biomarker detection. We showed that CNN most accurately determined relative contributions of each distinct dye-loaded nanorattle. CNN and comparative models were then used to analyze SERS spectra from a singleplexed, point-of-care assay detecting an mRNA biomarker for head and neck cancer in 20 samples. The CNN, trained on simulated multiplexed data, determined the correct dye contributions from the singleplex assay with RMSE_label = 6.42 × 10^-2. These results demonstrate the potential of CNN-based ML to advance SERS-based diagnostics.

PMID:37067872 | PMC:PMC10087982 | DOI:10.1002/jrs.6447

JMIR Ment Health. 2023 Apr 17;10:e44064. doi: 10.2196/44064.

ABSTRACT

BACKGROUND: Digital technologies play an increasingly important role in the lives of young people and have important effects on their mental health.

OBJECTIVE: We aimed to explore 3 key areas of the intersection between digital technology and mental health: the views and experiences of young people and clinicians about digital technology and mental health; implementation and barriers to the UK national guidance recommendation-that the discussion of digital technology use should form a core part of mental health assessment; and how digital technology might be used to support existing consultations.

METHODS: Two cross-sectional web-based surveys were conducted in 2020 between June and December, with mental health clinicians (n=99) and young people (n=320). Descriptive statistics were used to summarize the proportions. Multilinear regression was used to explore how the answers varied by gender, sexuality, and age. Thematic analysis was used to explore the contents of the extended free-text answers. Anxiety was measured using the Generalized Anxiety Disorder Questionnaire-7 (GAD-7).

RESULTS: Digital technology use was ubiquitous among young people, with positive and negative aspects acknowledged by both clinicians and young people. Negative experiences were common (131/284, 46.1%) and were associated with increased anxiety levels among young people (GAD-7 3.29; 95% CI 1.97-4.61; P<.001). Although the discussion of digital technology use was regarded as important by clinicians and acceptable by young people, less than half of clinicians (42/85, 49.4%) routinely asked about the use of digital technology and over a third of young people (48/121, 39.6%) who had received mental health care had never been asked about their digital technology use. The conversations were often experienced as unhelpful. Helpful conversations were characterized by greater depth and exploration of how an individual’s digital technology use related to mental health. Despite most clinicians (59/83, 71.1%) wanting training, very few (21/86, 24.4%) reported receiving training. Clinicians were open to viewing mental health data from apps or social media to help with consultations. Although young people were generally, in theory, comfortable sharing such data with health professionals, when presented with a binary choice, most reported not wanting to share social media (84/117, 71.8%) or app data (67/118, 56.8%) during consultations.

CONCLUSIONS: Digital technology use was common, and negative experiences were frequent and associated with anxiety. Over a third of young people were not asked about their digital technology use during mental health consultations, and potentially valuable information about relevant negative experiences on the web was not being captured during consultations. Clinicians would benefit from having access to training to support these discussions with young people. Although young people recognized that app data could be helpful to clinicians, they appeared hesitant to share their own data. This finding suggests that data sharing has barriers that need to be further explored.

PMID:37067869 | DOI:10.2196/44064

Genetics. 2023 Apr 17:iyad063. doi: 10.1093/genetics/iyad063. Online ahead of print.

ABSTRACT

Numerous studies over the last decade have demonstrated the utility of machine learning methods when applied to population genetic tasks. More recent studies show the potential of deep learning methods in particular, which allow researchers to approach problems without making prior assumptions about how the data should be summarized or manipulated, instead learning their own internal representation of the data in an attempt to maximize inferential accuracy. One type of deep neural network, called Generative Adversarial Networks (GANs), can even be used to generate new data, and this approach has been used to create individual artificial human genomes free from privacy concerns. In this study, we further explore the application of GANs in population genetics by designing and training a network to learn the statistical distribution of population genetic alignments (i.e. data sets consisting of sequences from an entire population sample) under several diverse evolutionary histories-the first GAN capable of performing this task. After testing multiple different neural network architectures, we report the results of a fully differentiable Deep-Convolutional Wasserstein GAN with gradient penalty that is capable of generating artificial examples of population genetic alignments that successfully mimic key aspects of the training data, including the site frequency spectrum, differentiation between populations, and patterns of linkage disequilibrium. We demonstrate consistent training success across various evolutionary models, including models of panmictic and subdivided populations, populations at equilibrium and experiencing changes in size, and populations experiencing either no selection or positive selection of various strengths, all without the need for extensive hyperparameter tuning. Overall, our findings highlight the ability of GANs to learn and mimic population genetic data and suggest future areas where this work can be applied in population genetics research that we discuss herein.

PMID:37067864 | DOI:10.1093/genetics/iyad063

J Med Internet Res. 2023 Apr 17;25:e42777. doi: 10.2196/42777.

ABSTRACT

BACKGROUND: Internet-based intervention platforms may improve access to mental health care for women with perinatal depression (PND). Though the majority of platforms in the market lack an evidence base, a small number of them are supported by research evidence.

OBJECTIVE: This study aims to assess the current status of internet-based PND intervention platforms supported by published evidence, understand the reasons behind the disappearance of any of these previously accessible platforms, examine adjustments made by those active platforms between research trials and market implementation, and evaluate their current quality.

METHODS: A cohort of internet-based PND intervention platforms was first identified by systematic searches in multiple academic databases from database inception until March 26, 2021. We searched on the World Wide Web and the iOS and Android app stores to assess which of these were available in the marketplace between April and May 2021. The basic characteristics of all platforms were collected. For inaccessible platforms, inquiries were made via email to the authors of publications to determine the reasons for their unavailability. We compared the intervention-related information of accessible platforms in the marketplace with that reported in original publications and conducted quality assessments using the App Evaluation Model of the American Psychiatric Association. Fisher exact tests were used to compare the functional characteristics in publications of available and unavailable platforms and to investigate potential associations between functional adjustments or quality indices and platform survival time.

RESULTS: Out of 35 platforms supported by research evidence, only 19 (54%) were still accessible in the marketplace. The main reason for platforms disappearing was the termination of research projects. No statistically significant differences were found in functional characteristics between available and unavailable platforms. A total of 18 (95%) platforms adapted their core functions from what was reported in related publications. The adjustments included changes to intervention methods (11/19, 58%), target population (10/19, 53%), human resources for intervention support (9/19, 47%), mood assessment and monitoring (8/19, 42%), communication modality (4/19, 21%), and platform type (2/19, 11%). Quality issues across platforms included low frequency of update, lack of crisis management mechanism, poor user interactivity, and weak evidence base or absence of citation of supporting evidence. Platforms that survived longer than 10 years had a higher tendency to use external resources from third parties compared to those that survived less than 10 years (P=.04). No significant differences were found for functional adjustments or other quality indices.

CONCLUSIONS: Internet-based platforms supported by evidence were not effectively translated into real-world practice. It is unclear if adjustments to accessible platforms made during actual operation may undermine the proven validity of the original research. Future research to explore the reasons behind the success of the implementation of evidence-based platforms in the marketplace is warranted.

PMID:37067855 | DOI:10.2196/42777

J Med Econ. 2023 Apr 17:1-53. doi: 10.1080/13696998.2023.2202600. Online ahead of print.

ABSTRACT

BACKGROUND AND OBJECTIVE: To assess the cost-utility of palivizumab versus no prophylaxis in preventing severe respiratory syncytial virus (RSV) infection in Canadian moderate-to-late preterm (32-35 weeks’ gestational age) infants using an: i) International Risk Scoring Tool (IRST); ii) Canadian RST (CRST).

METHODS: A decision tree was developed to assess cost-utility. Infants assessed at moderate- and high-risk of RSV-related hospitalization (RSVH) by the IRST or CRST received palivizumab or no prophylaxis and then progressed to either: i) RSVH; ii) emergency room/outpatient medically attended RSV-infection (MARI); or, iii) were uninfected/non-medically attended. Infants admitted to intensive care could incur mortality (0.43%). Respiratory morbidity was accounted in all uninfected surviving infants for 6 years or 18 years (RSVH/MARI). Palivizumab efficacy (72.2% RSVH reduction) and hospital outcomes were from the Canadian CARESS, PICNIC and RSV-Quebec studies. Palivizumab costs (50mg: CAN$752; 100mg: $1,505) were calculated from Canadian birth statistics combined with a growth algorithm. Healthcare/payer and societal costs (May 2022; 1.5% discounting) were included.

RESULTS: Cost per quality-adjusted life year (QALY) was $29,789 with the IRST (0.79 probability of being <$50,000) and $15,833 with the CRST (0.96 probability). The model was most sensitive to utility scores, long-term sequelae, and palivizumab cost. Vial sharing improved the incremental cost-utility ratio (IRST: $22,319; CRST: $9,231).

CONCLUSIONS: Palivizumab was highly cost-effective (vs no prophylaxis) in Canadian moderate-to-late preterm infants using either the IRST or CRST. The IRST has fewer risk factors than the CRST (3 vs 7, respectively), captures more potential RSVHs (85% vs 54%) and provides another option to guide cost-effective RSV prophylaxis in Canada.

PMID:37067826 | DOI:10.1080/13696998.2023.2202600

J Paediatr Child Health. 2023 Apr 17. doi: 10.1111/jpc.16396. Online ahead of print.

ABSTRACT

AIM: Rapid sequence intubation (RSI) in children is a low-incidence, high-risk event associated with cognitive overload and potential errors producing unfavourable outcomes. Cognitive aids, such as charts, algorithms and flow diagrams, are prompts that externalise and structure mental processes to reduce cognitive load, thereby reducing errors. The Paediatric Anaesthetic Emergency Drug Solution (PAEDS) approach combines a colour-coded chart and medication box with a simplified mathematical system of volume-based dosing; the effect of which on cognitive load during a simulated RSI has not previously been described.

METHODS: A randomised, cross-over trial was conducted with 26 multi-disciplinary emergency medicine clinicians (doctors and nurses) allocated to four groups, performing four high-fidelity RSI simulations, two mandating the use of the PAEDS approach. This mixed methods study followed the pragmatic ontology using grounded theory methodology. Qualitative data were collected from nine individual interviews by a process of thematic analysis via an inductive approach, to allow for appropriate open and axial coding to occur. Quantitative data collected included cognitive loading using the raw NASA-Task Load Index as well as time to intubation and drug dosage details to assess for safety.

RESULTS: Qualitative results showed that the PAEDS approach reduced cognitive loading through the use of both the labelled medication box and colour-coded medication charts. The PAEDS approach also showed improved perceived time pressure without feeling rushed, and with no recorded drug errors. Differences in the quantitative data for total cognitive load, error and time were not statistically significant, likely due to sample size.

CONCLUSION: The PAEDS approach is a multifaceted system which is not inferior to current practice, with some components described as an improvement. Further research on a larger sample size needs to be conducted to assess the aspects of the PAEDS approach both collectively and independently.

PMID:37067808 | DOI:10.1111/jpc.16396

JAMA Netw Open. 2023 Apr 3;6(4):e238437. doi: 10.1001/jamanetworkopen.2023.8437.

ABSTRACT

IMPORTANCE: Disparities in survival exist between non-Hispanic Black (hereafter, Black) and non-Hispanic White (hereafter, White) patients with uterine cancer.

OBJECTIVE: To investigate factors associated with racial disparities in survival between Black and White patients with uterine cancer.

DESIGN, SETTING, AND PATIENTS: This cohort study used data from the National Cancer Database on 274 838 Black and White patients who received a diagnosis of uterine cancer from January 1, 2004, to December 31, 2017, with follow-up through December 2020. Statistical analysis was performed in July 2022.

MAIN OUTCOMES AND MEASURES: Overall survival by self-reported race and evaluation of explanatory study factors associated with hazard ratio (HR) reduction for Black vs White patients. A propensity scoring approach was applied sequentially to balance racial differences in demographic characteristics, comorbidity score, neighborhood income, insurance status, histologic subtype, disease stage, and treatment.

RESULTS: The study included 32 230 Black female patients (mean [SD] age at diagnosis, 63.8 [10.0] years) and 242 608 White female patients (mean [SD] age at diagnosis, 63.5 [10.5] years) and had a median follow-up of 74.0 months (range, 43.5-113.8 months). Black patients were more likely than White patients to have low income (44.1% vs 14.0%), be uninsured (5.7% vs 2.6%), present with nonendometrioid histologic characteristics (46.1% vs 21.6%), have an advanced disease stage (34.1% vs 19.8%), receive first-line chemotherapy (33.8% vs 18.2%), and have worse 5-year survival (58.6% vs 78.5%). Among patients who received a diagnosis at younger than 65 years of age, the HR for death for Black vs White patients was 2.43 (95% CI, 2.34-2.52) in a baseline demographic-adjusted model and 1.29 (95% CI, 1.23-1.35) after balancing other factors. Comorbidity score, neighborhood income, insurance status, histologic subtype, disease stage, treatment, and unexplained factors accounted for 0.8%, 7.2%, 11.5%, 53.1%, 5.8%, 1.2%, and 20.4%, respectively, of the excess relative risk (ERR) among the younger Black vs White patients. Among patients 65 years or older, the HR for death for Black vs White patients was 1.87 (95% CI, 1.81-1.93) in the baseline model and 1.14 (95% CI, 1.09-1.19) after balancing other factors. Comorbidity score, neighborhood income, insurance status, histologic subtype, disease stage, treatment, and unexplained factors accounted for 3.0%, 7.5%, 0.0%, 56.2%, 10.6%, 6.9%, and 15.8%, respectively, of the ERR among Black vs White patients aged 65 years or older.

CONCLUSIONS AND RELEVANCE: This study suggests that histologic subtype was the dominant factor associated with racial survival disparity among patients with uterine cancer, while insurance status represented the main modifiable factor for women younger than 65 years. Additional studies of interactions between biology and social determinants of health are merited.

PMID:37067801 | DOI:10.1001/jamanetworkopen.2023.8437

JAMA Netw Open. 2023 Apr 3;6(4):e238655. doi: 10.1001/jamanetworkopen.2023.8655.

ABSTRACT

IMPORTANCE: Thyroid storm is the most severe form of thyrotoxicosis, with high mortality, and is treated with propylthiouracil and methimazole. Some guidelines recommend propylthiouracil over methimazole, although the difference in outcomes associated with each treatment is unclear.

OBJECTIVE: To compare outcomes associated with use of propylthiouracil vs methimazole for the treatment of thyroid storm.

DESIGN, SETTING, AND PARTICIPANTS: This comparative effectiveness study comprised a large, multicenter, US-based cohort from the Premier Healthcare Database between January 1, 2016, and December 31, 2020. It included 1383 adult patients admitted to intensive or intermediate care units with a diagnosis of thyroid storm per International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes and treated with either propylthiouracil or methimazole. Analyses were conducted from July 2022 to February 2023.

EXPOSURE: Patients received either propylthiouracil or methimazole for treatment of thyroid storm. Exposure was assigned based on the initial thionamide administered.

MAIN OUTCOMES AND MEASURES: The primary outcome was the adjusted risk difference of in-hospital death or discharge to hospice between patients treated with propylthiouracil and those treated with methimazole, assessed by targeted maximum likelihood estimation.

RESULTS: A total of 1383 patients (656 [47.4%] treated with propylthiouracil; mean [SD] age, 45 [16] years; 473 women [72.1%]; and 727 [52.6%] treated with methimazole; mean [SD] age, 45 [16] years; 520 women [71.5%]) were included in the study. The standardized mean difference for age was 0.056, and the standardized mean difference for sex was 0.013. The primary composite outcome occurred in 7.4% of of patients (102 of 1383; 95% CI, 6.0%-8.8%). A total of 8.5% (56 of 656; 95% CI, 6.4%-10.7%) of patients who initiated propylthiouracil and 6.3% (46 of 727; 95% CI, 4.6%-8.1%) who initiated methimazole died in the hospital (adjusted risk difference, 0.6% [95% CI, -1.8% to 3.0%]; P = .64). There were no significant differences in duration of organ support, total hospitalization costs, or rates of adverse events between the 2 treatment groups.

CONCLUSION AND RELEVANCE: In this comparative effectiveness study of a multicenter cohort of adult patients with thyroid storm, no significant differences were found in mortality or adverse events in patients who were treated with propylthiouracil or methimazole. Thus, current guidelines recommending propylthiouracil over methimazole for treatment of thyroid storm may merit reevaluation.

PMID:37067797 | DOI:10.1001/jamanetworkopen.2023.8655

JAMA Pediatr. 2023 Apr 17. doi: 10.1001/jamapediatrics.2023.0688. Online ahead of print.

ABSTRACT

IMPORTANCE: The capacity for regulation of energy intake (REI) to match energy needs is thought to contribute to differences in weight gain, and preventing excess infant weight gain is a priority.

OBJECTIVE: To determine capacity for REI across infancy.

DESIGN, SETTING, AND PARTICIPANTS: For this cohort study, a convenience sample of mother-infant dyads was recruited from the community in Michigan between 2015 and 2019. Inclusion criteria were healthy, full-term infants with weight appropriate for gestational age; biological mothers who were 18 years or older, English speaking, and a legal and custodial guardian; and infant having had consumed 2 oz or more in 1 feeding from an artificial nipple at least once per week. Infants were followed in the home setting with staff support for up to 12 months.

INTERVENTIONS: Mother-infant dyads participated at infant age 1, 2.5, 5, 7, 10, and 12 months. In the intervention condition, mothers offered a feeding every hour for 6 hours. In the control condition, mothers fed infants as they typically would for 6 hours. Intake was recorded and kilocalories calculated.

MAIN OUTCOMES AND MEASURES: Capacity for REI was indexed as the difference in intake in kilocalories per kilogram of body weight (intervention minus control condition); a value of 0 indicated perfect REI. Maternal and infant characteristics were obtained by questionnaire, and anthropometry was measured. Using multiple imputation, the intercept and slope for difference in kilocalories per kilogram across the 6 age points were estimated using mixed models accounting for repeated measures within participants. Statistical analyses were conducted between September 2021 and February 2023.

RESULTS: The sample included 175 infants (87 [49.71%] female, 88 [50.29%] male; 494 pairs of intervention and control conditions and 4630 feedings). The mean (SD) 12-month weight-for-age z score was 0.1 (0.8). Mean (SD) gestational age as 39.55 (1.05) weeks, and mean (SD) birth weight was 3.43 (0.41) kg. Mean (SD) breastfeeding duration for those who reported stopping by 12 months was 17.83 (12.03) weeks. As designed, the intervention (compared with control) condition included more feedings at shorter intervals. After collapsing the data across age points in a mixed model accounting for repeated measures within participants, the REI estimate at 1 month differed from 0. On average, infants ate 5.21 kcal/kg (95% CI, 2.89-7.54 kcal/kg) more in the frequent feeding intervention condition than in the ad lib feeding control condition. This difference did not significantly change over 12 months of infancy (REI slope = -0.01 kcal/kg per month; 95% CI, -0.02 to 0.03 kcal/kg per month).

CONCLUSIONS AND RELEVANCE: The study’s findings suggested that, on average, when offered more frequent feedings, healthy, full-term infants may overeat. The results provide support for responsive feeding as a strategy for preventing excess infant weight gain.

PMID:37067796 | DOI:10.1001/jamapediatrics.2023.0688