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Enhancing access to healthcare remains a formidable challenge in rural regions of low- and lower-middle-income countries. Amid evolving healthcare challenges, telerheumatology provides opportunities to bridge gaps and expand access to rheumatology care, particularly in remote areas. We describe a pilot telerheumatology program and its cost-, time-, and travel-saving potential in a remote rural setting in northern Pakistan. The telerheumatology program commenced at the Pakistan Institute of Medical Sciences Islamabad, providing services through video consultations to a basic health unit in the Gilgit-Baltistan region. Patients visiting from the Gilgit-Baltistan region willing to participate were recruited in the program. Demographics and logistical metrics were recorded in a dedicated registry. A total of 533 consultations were carried out from April 2022 to April 2023. The majority of the patients were female (318/533, 59.7%). The median age of patients was 50 ± 15.7 years. The average wait time for consultation was 20 ± 13 min. The average travel time to reach telecentre was 59 ± 53 min. The average travel cost to reach telecentre was 379 ± 780 PKR (1.85 ± 3.81 USD). The average duration of consultation was 15 ± 5 min. The most common diagnosis for consultation was knee osteoarthritis (237, 44.5%), chronic low back pain (118, 22.1%), and rheumatoid arthritis (42, 7.9%). On average, patients saved 787 ± 29 km of distance, 15 ± 1 h of traveling, and 6702 ± 535 PKR (33 ± 3 USD) that would have been required to travel to our tertiary care hospital. Telerheumatology substantially reduced travel time, distance, and cost for patients. It has the potential to deliver outpatient rheumatology consultation in an economically efficient manner, effectively breaking geographical barriers and expanding access to essential services for patients in remote areas.
Subject(s)
Health Services Accessibility , Rheumatology , Telemedicine , Humans , Pakistan , Pilot Projects , Female , Male , Middle Aged , Rheumatology/economics , Adult , Health Services Accessibility/economics , Telemedicine/economics , Rural Population , Aged , Rheumatic Diseases/therapy , Rheumatic Diseases/economics , Travel/economics , Remote Consultation/economics , Rural Health Services/economicsABSTRACT
In exploring therapeutic options for ischemic heart disease (IHD) and heart failure, cell-based cardiac repair has gained prominence. This systematic review delves into the current state of knowledge surrounding cell-based therapies for cardiac repair. Employing a comprehensive search across relevant databases, the study identifies 35 included studies with diverse cell types and methodologies. Encouragingly, these findings reveal the promise of cell-based therapies in cardiac repair, demonstrating significant enhancements in left ventricular ejection fraction (LVEF) across the studies. Mechanisms of action involve growth factors that stimulate angiogenesis, differentiation, and the survival of transplanted cells. Despite these positive outcomes, challenges persist, including low engraftment rates, limitations in cell differentiation, and variations in clinical reproducibility. The optimal dosage and frequency of cell administration remain subjects of debate, with potential benefits from repeated dosing. Additionally, the choice between autologous and allogeneic stem cell transplantation poses a critical decision. This systematic review underscores the potential of cell-based therapies for cardiac repair, bearing implications for innovative treatments in heart diseases. However, further research is imperative to optimize cell type selection, delivery techniques, and long-term efficacy, fostering a more comprehensive understanding of cell-based cardiac repair.
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Importance: Blood pressure response during acute exercise (exercise blood pressure [EBP]) is associated with the future risk of hypertension and cardiovascular disease (CVD). Biochemical characterization of EBP could inform disease biology and identify novel biomarkers of future hypertension. Objective: To identify protein markers associated with EBP and test their association with incident hypertension. Design, Setting, and Participants: This study assayed 4977 plasma proteins in 681 healthy participants (from 763 assessed) of the Health, Risk Factors, Exercise Training and Genetics (HERITAGE; data collection from January 1993 to December 1997 and plasma proteomics from January 2019 to January 2020) Family Study at rest who underwent 2 cardiopulmonary exercise tests. Individuals were free of CVD at the time of recruitment. Individuals with resting SBP ≥160 mm Hg or DBP ≥100 mm Hg or taking antihypertensive drug therapy were excluded from the study. The association between resting plasma protein levels to both resting BP and EBP was evaluated. Proteins associated with EBP were analyzed for their association with incident hypertension in the Framingham Heart Study (FHS; n = 1177) and validated in the Jackson Heart Study (JHS; n = 772) and Multi-Ethnic Study of Atherosclerosis (MESA; n = 1367). Proteins associated with incident hypertension were tested for putative causal links in approximately 700â¯000 individuals using cis-protein quantitative loci mendelian randomization (cis-MR). Data were analyzed from January 2023 to January 2024. Exposures: Plasma proteins. Main Outcomes and Measures: EBP was defined as the BP response during a fixed workload (50 W) on a cycle ergometer. Hypertension was defined as BP ≥140/90 mm Hg or taking antihypertensive medication. Results: Among the 681 participants in the HERITAGE Family Study, the mean (SD) age was 34 (13) years; 366 participants (54%) were female; 238 (35%) were self-reported Black and 443 (65%) were self-reported White. Proteomic profiling of EBP revealed 34 proteins that would not have otherwise been identified through profiling of resting BP alone. Transforming growth factor ß receptor 3 (TGFBR3) and prostaglandin D2 synthase (PTGDS) had the strongest association with exercise systolic BP (SBP) and diastolic BP (DBP), respectively (TGFBR3: exercise SBP, ß estimate, -3.39; 95% CI, -4.79 to -2.00; P = 2.33 × 10-6; PTGDS: exercise DBP ß estimate, -2.50; 95% CI, -3.29 to -1.70; P = 1.18 × 10-9). In fully adjusted models, TGFBR3 was inversely associated with incident hypertension in FHS, JHS, and MESA (hazard ratio [HR]: FHS, 0.86; 95% CI, 0.75-0.97; P = .01; JHS, 0.87; 95% CI, 0.77-0.97; P = .02; MESA, 0.84; 95% CI, 0.71-0.98; P = .03; pooled cohort, 0.86; 95% CI, 0.79-0.92; P = 6 × 10-5). Using cis-MR, genetically predicted levels of TGFBR3 were associated with SBP, hypertension, and CVD events (SBP: ß, -0.38; 95% CI, -0.64 to -0.11; P = .006; hypertension: odds ratio [OR], 0.99; 95% CI, 0.98-0.99; P < .001; heart failure with hypertension: OR, 0.86; 95% CI, 0.77-0.97; P = .01; CVD: OR, 0.84; 95% CI, 0.77-0.92; P = 8 × 10-5; cerebrovascular events: OR, 0.77; 95% CI, 0.70-0.85; P = 5 × 10-7). Conclusions and Relevance: Plasma proteomic profiling of EBP identified a novel protein, TGFBR3, which may protect against elevated BP and long-term CVD outcomes.
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Inherited cardiomyopathies are genetic diseases that can lead to heart failure and sudden cardiac death. These conditions tend to run in families, following an autosomal dominant pattern where first-degree relatives have a 50% chance of carrying the pathogenic variant. Despite significant advancements and increased accessibility of genetic testing, accurately predicting the phenotypic expression of these conditions remains challenging due to the inherent variability in their clinical manifestations and the incomplete penetrance observed. This poses challenges in providing patient care and effectively communicating the potential risk of future disease to patients and their families. To address these challenges, this review aims to synthesize the available evidence on penetrance, expressivity, and factors influencing disease expression to improve communication and risk assessment for patients with inherited cardiomyopathies and their family members.
Subject(s)
Cardiomyopathies , Genetic Testing , Penetrance , Phenotype , Humans , Cardiomyopathies/genetics , Cardiomyopathies/physiopathology , Genetic Testing/methods , Genetic Predisposition to Disease , Death, Sudden, Cardiac/etiology , Death, Sudden, Cardiac/prevention & control , Risk Assessment/methods , MutationABSTRACT
BACKGROUND: A validated tool may facilitate assessing the severity of peritonitis among surgical patients. This study evaluates the predictive role of Acute Physiology and Chronic Health Evaluation II (APACHE II) in the surgical outcomes of patients managed for peritonitis in Abuja. METHOD: This is a prospective study of consecutive adult patients managed for peritonitis by the general surgery unit of National Hospital Abuja (NHA) over a 19-month period (September 2020 through March 2022). Patient characteristics and treatment outcomes were recorded in a structured proforma and analyzed using SPSS Statistics version 25 (IBM Corp., Released 2017; IBM SPSS Statistics for Windows, Version 25.0; Armonk, NY: IBM Corp.). The accuracy, sensitivity, specificity, and threshold of APACHE II were derived from the receiver operating characteristic (ROC) curve analysis and its coordinates. RESULTS: There were 54 patients with peritonitis during the study period, with a male-to-female ratio of 2.6:1. This study's mortality and morbidity rates were 13.0% and 63.0%, respectively. The APACHE II score at admission was positively correlated with the likelihood of postoperative mortality, morbidity, number of postoperative complications, ICU admission, and length of hospital admission. The average APACHE II score of patients in this study was 7.1±5.2. APACHE II best-predicted mortality by the ROC curve at a threshold point of 9 (sensitivity of 85.7%, specificity of 70.2%, the accuracy of 86.8%, P-value 0.002). At a threshold score of 6, APACHE II was significantly associated with the occurrence of postoperative morbidity (sensitivity of 74.3%, specificity of 73.7%, accuracy of 75.2%, P-value = 0.043). CONCLUSIONS: This study confirms that the APACHE II score at admission can predict the outcome of surgery within the first 30 days post-surgery among adult patients who had peritonitis at NHA.
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Optical microcomb underpins a wide range of applications from communication, metrology, to sensing. Although extensively explored in recent years, challenges remain in key aspects of microcomb such as complex soliton initialization, low power efficiency, and limited comb reconfigurability. Here we present an on-chip microcomb laser to address these key challenges. Realized with integration between III and V gain chip and a thin-film lithium niobate (TFLN) photonic integrated circuit (PIC), the laser directly emits mode-locked microcomb on demand with robust turnkey operation inherently built in, with individual comb linewidth down to 600 Hz, whole-comb frequency tuning rate exceeding 2.4 × 1017 Hz/s, and 100% utilization of optical power fully contributing to comb generation. The demonstrated approach unifies architecture and operation simplicity, electro-optic reconfigurability, high-speed tunability, and multifunctional capability enabled by TFLN PIC, opening up a great avenue towards on-demand generation of mode-locked microcomb that is of great potential for broad applications.
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Measles is a highly infectious, vaccine-preventable viral disease that runs a devastating course in developing countries due to its association with malnutrition and poor immunization coverage. Subcutaneous emphysema (SE) is a rare complication of measles that can be challenging to manage and may portend poor outcomes if untreated. We present a case of a two-year-old unimmunized rural dweller who presented with facial, neck, and chest swellings three days after being managed for measles exanthem from a referral hospital. Clinical findings were consistent with massive SE comorbid with malnutrition complicating the convalescent stage of measles. The child failed to improve with conservative management but responded to closed thoracostomy tube drainage (CTTD) through an underwater seal bottle with intermittent negative pressure wound therapy (NPWT). The child spent 47 days in the hospital during which the social welfare unit of the hospital supported the treatment. SE is a rare complication of measles infection that can be challenging to manage, especially when comorbid with malnutrition in an indigent child. The application of a multidisciplinary team approach and the use of CTTD with NPWT may shorten the duration of hospital stay for the patient.
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Artificial intelligence (AI) is being employed in brine mining to enhance the extraction of lithium, vital for the manufacturing of lithium-ion batteries, through improved recovery efficiencies and the reduction of energy consumption. An innovative approach was proposed combining Emotional Neural Networks (ENN) and Random Forest (RF) algorithms to elucidate the adsorption energy (AE) (kcal mol-1) of Li+ ions by utilizing crown ether (CE)-incorporated honeycomb 2D nanomaterials. The screening and feature engineering analysis of honeycomb-patterned 2D materials and individual CE were conducted through Density Functional Theory (DFT) and Gaussian 16 simulations. The selected honeycomb-patterned 2D materials encompass graphene, silicene, and hexagonal boron nitride, while the specific CEs evaluated are 15-crown-5 and 18-crown-6. The crown-passivated 2D surfaces held a significant adsorption site through van der Waals forces for efficient recovery of Li+ ions. ENN predicted the targeted adsorption sites with high precision and minimal deviation. The eTAI (XAI) based Shapley Additive exPlanations (SHAP) was also explored for insight into the feature importance of CE embedded 2D nanomaterials for the recovery of Li+ ions. The extreme gradient boosting algorithm (XGBoost) model demonstrated a RT-2-MAPE = 0.4618% and ENN-2-MAPE = 0.4839% for the feature engineering analysis. This research would be an insight into the AI-driven nanotechnology that presents a viable and sustainable approach for the extraction of natural resources through the application of brine mining.
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Genetic correlation refers to the correlation between genetic determinants of a pair of traits. When using individual-level data, it is typically estimated based on a bivariate model specification where the correlation between the two variables is identifiable and can be estimated from a covariance model that incorporates the genetic relationship between individuals, e.g., using a pre-specified kinship matrix. Inference relying on asymptotic normality of the genetic correlation parameter estimates may be inaccurate when the sample size is low, when the genetic correlation is close to the boundary of the parameter space, and when the heritability of at least one of the traits is low. We address this problem by developing a parametric bootstrap procedure to construct confidence intervals for genetic correlation estimates. The procedure simulates paired traits under a range of heritability and genetic correlation parameters, and it uses the population structure encapsulated by the kinship matrix. Heritabilities and genetic correlations are estimated using the close-form, method of moment, Haseman-Elston regression estimators. The proposed parametric bootstrap procedure is especially useful when genetic correlations are computed on pairs of thousands of traits measured on the same exact set of individuals. We demonstrate the parametric bootstrap approach on a proteomics dataset from the Jackson Heart Study.
Subject(s)
Models, Genetic , Humans , Protein Interaction Maps/genetics , Confidence Intervals , Computer Simulation , Algorithms , PhenotypeABSTRACT
Metformin is a widely prescribed anti-diabetic medicine that also reduces body weight. There is ongoing debate about the mechanisms that mediate metformin's effects on energy balance. Here, we show that metformin is a powerful pharmacological inducer of the anorexigenic metabolite N-lactoyl-phenylalanine (Lac-Phe) in cells, in mice and two independent human cohorts. Metformin drives Lac-Phe biosynthesis through the inhibition of complex I, increased glycolytic flux and intracellular lactate mass action. Intestinal epithelial CNDP2+ cells, not macrophages, are the principal in vivo source of basal and metformin-inducible Lac-Phe. Genetic ablation of Lac-Phe biosynthesis in male mice renders animals resistant to the effects of metformin on food intake and body weight. Lastly, mediation analyses support a role for Lac-Phe as a downstream effector of metformin's effects on body mass index in participants of a large population-based observational cohort, the Multi-Ethnic Study of Atherosclerosis. Together, these data establish Lac-Phe as a critical mediator of the body weight-lowering effects of metformin.
Subject(s)
Body Weight , Eating , Metformin , Metformin/pharmacology , Animals , Humans , Body Weight/drug effects , Mice , Eating/drug effects , Male , Hypoglycemic Agents/pharmacology , Hypoglycemic Agents/therapeutic use , Phenylalanine/pharmacology , Phenylalanine/metabolism , Dipeptides/pharmacologyABSTRACT
OBJECTIVE: Rathke cleft cysts (RCCs) are benign, epithelial-lined sellar lesions that arise from remnants of the craniopharyngeal duct. Due to their rarity in the pediatric population, data are limited regarding the natural history and optimal management of growing or symptomatic RCCs. We present our institutional experience with the surgical management of RCCs. METHODS: We performed a retrospective study of consecutive RCC patients ≤ 18 years old treated surgically at our institution between 2006 and 2022. RESULTS: Overall, 567 patients with a diagnosis of pituitary mass or cyst were identified. Of these, 31 had a histopathological diagnosis of RCC, 58% female and 42% male. The mean age was 13.2 ± 4.2 years. Presenting symptoms included headache (58%), visual changes (32%), and endocrinopathies or growth delay (26%); 13% were identified incidentally and subsequently demonstrated growth on serial imaging. Six percent presented with symptomatic intralesional hemorrhage. Surgical approach was transsphenoidal for 90% of patients and orbitozygomatic for 10%. Preoperative headaches resolved in 61% of patients and preoperative visual deficits improvement in 55% after surgery. New pituitary axis deficits were seen in 9.7% of patients. Only two complications occurred from a first-time surgery: one cerebrospinal fluid leak requiring lumbar drain placement, and one case of epistaxis requiring cauterization. No patients experienced new visual or neurological deficits. Patients were followed postoperatively with serial imaging at a mean follow-up was 62.9 ± 58.4 months. Recurrence requiring reoperation occurred in 32% of patients. Five-year progression-free survival was 47.9%. Except for one patient with multiple neurological deficits from a concurrent tectal glioma, all patients had a modified Rankin Scale score of 0 or 1 (good outcome) at last follow-up. CONCLUSION: Due to their secretory epithelium, pediatric RCCs may demonstrate rapid growth and can cause symptoms due to local mass effect. Surgical management of symptomatic or growing pediatric RCCs via cyst fenestration or partial resection of the cyst wall can be performed safely, with good neurologic outcomes. There is a nontrivial risk of endocrinologic injury, and long-term follow up is needed due to high recurrence rates.
Subject(s)
Carcinoma, Renal Cell , Central Nervous System Cysts , Cysts , Kidney Neoplasms , Humans , Child , Male , Female , Adolescent , Retrospective Studies , Central Nervous System Cysts/surgeryABSTRACT
OBJECTIVES: The uterine cancer (UC) mortality rate in the UK is significantly higher for women who belong to a Black ethnic group compared to those from other ethnic groups. This study aimed to understand the views and experiences of UC amongst Black ethnic minority women in the UK, with a focus on awareness and presentation of red-flag symptoms. METHODS: Women of Black African, Caribbean, Black British and Mixed-Black ethnicity were purposefully recruited to participate in focus groups and individual semi-structured interviews. RESULTS: Twenty women from different regions in England participated in the study. Reflexive thematic analysis of the data led to the identification of three main themes: 1) Healthcare inequities; 2) Support and sense making with other Black women; and 3) Knowledge dissemination, mobilisation, and empowerment. Perceptions of inequitable healthcare provision and distrust influenced how participants, and their peer networks, approached seeking assistance from healthcare professionals. Concerns were also raised about culturally insensitive information resources, including issues of language, literacy, and representation, all of which served as potential barriers for women within Black ethnic minority groups. CONCLUSIONS: The deficiency of targeted knowledge mobilisation and specific UC information aimed at Black ethnicity women living in the UK, reportedly contributes to the dissemination of misconceptions and an atmosphere of apprehension around a UC diagnosis. The insights from this study highlight the significance of designing culturally sensitive strategies to promote informed decision-making and empower the dissemination of accurate health knowledge amongst Black women.
Subject(s)
Ethnicity , Uterine Neoplasms , Humans , Female , Minority Groups , Caribbean Region , EnglandABSTRACT
Abstract The aim of the present study is to assess the effects of selenium nanoparticles on the growth, hematology and nutrients digestibility of Labeorohita fingerlings. Fingerlings were fed with seven isocaloric sunflower meal-based diet supplemented with different concentrations of nanoparticles naming T1 to T7 (0, 0.5, 1, 1.5, 2, 2.5, and 3 mg/kg), with 5% wet body weight while chromic oxide was used as an indigestible marker. After experimentation for 90 days T3 treated group (1mg/kg -1Se-nano level) showed the best result in hematological parameters (WBCs 7.97 ×103mm-3, RBCs 2.98 ×106 mm-3 and Platelet count 67), nutrient digestibility (crude protein: 74%, ether extract: 76%, gross energy: 70%) and growth performance (weight gain 13.24 g, weight gain% 198, feed conversion ratio 1.5, survival rate 100%) as compared to the other treatment groups. Specific growth rates were found significantly higher in T5 than in other groups. The present study indicated positive effect of 1 mg/kg Se-nanoparticles on growth advancement, hematological parameters, and nutrients digestibility of L. rohita fingerlings.
Resumo O objetivo do presente estudo é avaliar os efeitos das nanopartículas de selênio no crescimento, hematologia e digestibilidade dos nutrientes de alevinos de Labeo rohita. Os alevinos foram alimentados com sete dietas isocalóricas à base de farinha de girassol suplementada com diferentes concentrações de nanopartículas, nomeando T1 a T7 (0, 0,5, 1, 1,5, 2, 2,5 e 3 mg / kg), com 5% do peso corporal úmido enquanto o óxido crômico foi usado como um marcador indigesto. Após a experimentação por 90 dias, o grupo tratado com T3 (nível 1mg / kg -1Se-nano) mostrou o melhor resultado em parâmetros hematológicos (WBCs 7,97 × 103mm-3, RBCs 2,98 × 106mm-3 e contagem de plaquetas 67), digestibilidade dos nutrientes (proteína bruta: 74%, extrato de éter: 76%, energia bruta: 70%) e desempenho de crescimento (ganho de peso 13,24 g, ganho de peso % 198, taxa de conversão alimentar 1,5, taxa de sobrevivência 100%) em comparação com os outros grupos de tratamento. As taxas de crescimento específicas foram encontradas significativamente mais altas em T5 do que em outros grupos. O presente estudo indicou efeito positivo de 1 mg / kg de nanopartículas de Se no avanço do crescimento, parâmetros hematológicos e digestibilidade de nutrientes de alevinos de L. rohita.
ABSTRACT
Abstract The aim of the present study is to assess the effects of selenium nanoparticles on the growth, hematology and nutrients digestibility of Labeorohita fingerlings. Fingerlings were fed with seven isocaloric sunflower meal-based diet supplemented with different concentrations of nanoparticles naming T1 to T7 (0, 0.5, 1, 1.5, 2, 2.5, and 3 mg/kg), with 5% wet body weight while chromic oxide was used as an indigestible marker. After experimentation for 90 days T3 treated group (1mg/kg -1Se-nano level) showed the best result in hematological parameters (WBC's 7.97 ×103mm-3, RBC's 2.98 ×106 mm-3 and Platelet count 67), nutrient digestibility (crude protein: 74%, ether extract: 76%, gross energy: 70%) and growth performance (weight gain 13.24 g, weight gain% 198, feed conversion ratio 1.5, survival rate 100%) as compared to the other treatment groups. Specific growth rates were found significantly higher in T5 than in other groups. The present study indicated positive effect of 1 mg/kg Se-nanoparticles on growth advancement, hematological parameters, and nutrients digestibility of L. rohita fingerlings.
Resumo O objetivo do presente estudo é avaliar os efeitos das nanopartículas de selênio no crescimento, hematologia e digestibilidade dos nutrientes de alevinos de Labeo rohita. Os alevinos foram alimentados com sete dietas isocalóricas à base de farinha de girassol suplementada com diferentes concentrações de nanopartículas, nomeando T1 a T7 (0, 0,5, 1, 1,5, 2, 2,5 e 3 mg / kg), com 5% do peso corporal úmido enquanto o óxido crômico foi usado como um marcador indigesto. Após a experimentação por 90 dias, o grupo tratado com T3 (nível 1mg / kg -1Se-nano) mostrou o melhor resultado em parâmetros hematológicos (WBC's 7,97 × 103mm-3, RBC's 2,98 × 106mm-3 e contagem de plaquetas 67), digestibilidade dos nutrientes (proteína bruta: 74%, extrato de éter: 76%, energia bruta: 70%) e desempenho de crescimento (ganho de peso 13,24 g, ganho de peso % 198, taxa de conversão alimentar 1,5, taxa de sobrevivência 100%) em comparação com os outros grupos de tratamento. As taxas de crescimento específicas foram encontradas significativamente mais altas em T5 do que em outros grupos. O presente estudo indicou efeito positivo de 1 mg / kg de nanopartículas de Se no avanço do crescimento, parâmetros hematológicos e digestibilidade de nutrientes de alevinos de L. rohita.
Subject(s)
Animals , Nanoparticles , Helianthus , Nutrients , Dietary Supplements , Diet , Animal Feed/analysis , Animal Nutritional Physiological PhenomenaABSTRACT
The phase-coherent frequency division of a stabilized optical reference laser to the microwave domain is made possible by optical-frequency combs (OFCs)1,2. OFC-based clockworks3-6 lock one comb tooth to a reference laser, which probes a stable atomic transition, usually through an active servo that increases the complexity of the OFC photonic and electronic integration for fieldable clock applications. Here, we demonstrate that the Kerr nonlinearity enables passive, electronics-free synchronization of a microresonator-based dissipative Kerr soliton (DKS) OFC7 to an externally injected reference laser. We present a theoretical model explaining this Kerr-induced synchronization (KIS), which closely matches experimental results based on a chip-integrated, silicon nitride, micro-ring resonator. Once synchronized, the reference laser captures an OFC tooth, so that tuning its frequency provides direct external control of the OFC repetition rate. We also show that the stability of the repetition rate is linked to that of the reference laser through the expected frequency division factor. Finally, KIS of an octave-spanning DKS exhibits enhancement of the opposite dispersive wave, consistent with the theoretical model, and enables improved self-referencing and access to the OFC carrier-envelope offset frequency. The KIS-mediated enhancements we demonstrate can be directly implemented in integrated optical clocks and chip-scale low-noise microwave generators.
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The prediction of the yields of light olefins in the direct conversion of crude oil to chemicals requires the development of a robust model that represents the crude-to-chemical conversion processes. This study utilizes artificial intelligence (AI) and machine learning algorithms to develop single and ensemble learning models that predict the yields of ethylene and propylene. Four single-model AI techniques and four ensemble paradigms were developed using experimental data derived from the catalytic cracking experiments of various crude oil fractions in the advanced catalyst evaluation reactor unit. The temperature, feed type, feed conversion, total gas, dry gas, and coke were used as independent variables. Correlation matrix analyses were conducted to filter the input combinations into three different classes (M1, M2, and M3) based on the relationship between dependent and independent variables, and three performance metrics comprising the coefficient of determination (R2), Pearson correlation coefficient (PCC), and mean square error (MSE) were used to evaluate the prediction performance of the developed models in both calibration and validations stages. All four single models have very low R2 and PCC values (as low as 0.07) and very high MSE values (up to 4.92 wt %) for M1 and M2 in both calibration and validation phases. However, the ensemble ML models show R2 and PCC values of 0.99-1 and an MSE value of 0.01 wt % for M1, M2, and M3 input combinations. Therefore, ensemble paradigms improve the performance accuracy of single models by up to 58 and 62% in the calibration and validation phases, respectively. The ensemble paradigms predict with high accuracy the yield of ethylene and propylene in the catalytic cracking of crude oil and its fractions.
ABSTRACT
Metformin is a widely prescribed anti-diabetic medicine that also reduces body weight. The mechanisms that mediate metformin's effects on energy balance remain incompletely defined. Here we show that metformin is a powerful pharmacological inducer of the anorexigenic metabolite Lac-Phe in mice as well as in two independent human cohorts. In cell culture, metformin drives Lac-Phe biosynthesis via inhibition of complex I, increased glycolytic flux, and intracellular lactate mass action. Other biguanides and structurally distinct inhibitors of oxidative phosphorylation also increase Lac-Phe levels in vitro. Genetic ablation of CNDP2, the principal biosynthetic enzyme for Lac-Phe, in mice renders animals resistant to metformin's anorexigenic and anti-obesity effects. Mediation analyses also support a role for Lac-Phe in metformin's effect on body mass index in humans. These data establish the CNDP2/Lac-Phe pathway as a critical mediator of the effects of metformin on energy balance.
ABSTRACT
Endoscopic retrograde cholangiopancreatography (ERCP) with endoscopic sphincterotomy (EST) has been proven efficacious in the removal of CBD stones. Even after endoscopic stone removal, recurring cholangitis due to a residual common bile duct (CBD) stone is prevalent in clinical practice with a residual recurrence rate of 4-24% after successful stone retrieval. This comprehensive study and meta-analysis aimed to determine if preventive saline irrigation of the bile duct (PSIB) reduces the amount of residual CBD stones. Through a comprehensive search of PubMed, EMBASE, Cochrane Library, and Web of Science until November 20, 2022, we identified 164 articles comparing the efficacy of PSIB and non-PSIB post-endoscopic CBD stone removal. After stringent selection, three studies were included for meta-analysis using ReviewManager (ReVman version 5.4.1; Cochrane, London, UK). Using a random effect (RE) model, we derived a pooled odds ratio (OR) with confidence interval (CI) (95%CI). A total of three studies have been included in the analysis. Out of which, two are randomized controlled trials (RCTs) and one is a non-randomized study. Out of 323 patients, 157 underwent PSIB after an endoscopic stone removal of CBD stones to reduce the residual of CBD stones, whereas 166 did not undergo saline irrigation (non-PSIB). In our analysis, PSIB significantly reduced the risk of residual stones (OR: 0.22, 95%CI: 0.11-0.45). However, there was no notable link between PSIB and post-irrigation cholangitis (OR: 1.08, 95%CI: 0.21-2.21). Although not statistically significant, PSIB showed a trend toward lowered risks of post-procedural pancreatitis (OR: 0.65), bleeding (OR: 0.68), and other complications (OR: 0.64). PSIB effectively reduces residual CBD stones after endoscopy, offering a cost-effective alternative to invasive procedures such as intraductal ultrasound (IDUS). However, larger RCTs are needed to validate its definitive role.
ABSTRACT
We present the case of a 60-year-old man who presented with a post-myocardial infarction ventricular septal rupture caused by a delayed presentation of myocardial infarction. Despite revascularization, hemodynamic stability, and a 10-day delay until operative management to allow for tissue healing, the patient experienced a fatal recurrent postoperative ventricular septal rupture. (Level of Difficulty: Beginner.).