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Purpose:To evaluate the medical accuracy in discussions of stem cell therapy for retinal diseases on a social media internet forum (Reddit). Methods:A cross-sectional study assessed 11 Reddit forums and 411 unique comments from 2017 to 2022. Evaluated participants were all anonymous Reddit users. Discussions were independently examined for medical accuracy by a board-certified, fellowship-trained retina surgeon in active practice. Results:Reddit users self-identified mainly as prospective patients followed by research students and physicians or healthcare workers. Inquiries mostly regarded stem cell treatment for macular degeneration. Thirty-six percent of the forum’s content was found to be inaccurate or misleading. When specifically considering factual comments, the inaccuracy rate increased to 54%. Identified gaps in knowledge mostly regarded the current state of the technology (25%) followed by misinterpretation of trial results (16%) and scam treatments (14%). Most inaccurate or misleading comments favored stem cell advancements (72%). Conclusions:This study highlights the gaps in knowledge and areas of medical misinformation regarding ocular stem cell therapies shared by individuals on Reddit.

Support vector machines (SVMs) are popular learning algorithms to deal with binary classification problems. They traditionally assume equal misclassification costs for each class; however, real-world problems may have an uneven class distribution. This article introduces EBCS-SVM: evolutionary bilevel cost-sensitive SVMs. EBCS-SVM handles imbalanced classification problems by simultaneously learning the support vectors and optimizing the SVM hyperparameters, which comprise the kernel parameter and misclassification costs. The resulting optimization problem is a bilevel problem, where the lower level determines the support vectors and the upper level the hyperparameters. This optimization problem is solved using an evolutionary algorithm (EA) at the upper level and sequential minimal optimization (SMO) at the lower level. These two methods work in a nested fashion, that is, the optimal support vectors help guide the search of the hyperparameters, and the lower level is initialized based on previous successful solutions. The proposed method is assessed using 70 datasets of imbalanced classification and compared with several state-of-the-art methods. The experimental results, supported by a Bayesian test, provided evidence of the effectiveness of EBCS-SVM when working with highly imbalanced datasets.

Purpose: To investigate clinical features and outcomes of conjunctival melanoma classified by tumour origin. Methods: Retrospective review of conjunctival melanoma patients at a single ocular oncology centre between April 18, 1974 and September 9, 2019. Lesions were divided into three tumour origin groups (primary acquired melanosis [PAM], nevus, and de novo) and clinical features and outcomes were compared. Results: There were 629 patients with conjunctival melanoma that arose from PAM (n= 476, 76%), nevus (n= 59, 9%), or de novo (n= 94, 15%). A comparison (PAM vs. nevus vs. de novo) revealed patients with tumours arising from PAM presented with older mean age (62 vs. 52 vs. 55 years, p< 0.001), worse initial logMAR visual acuity (Snellen equivalent 20/30 vs. 20/25 vs. 20/25, p= 0.03), and greater clock hour involvement (4.8 vs. 4.0 vs. 3.2, p< 0.001). Tumours arising from nevus had lower frequency of fornix (31% vs. 9% vs. 24%, p= 0.02) and tarsal involvement (29% vs. 9% vs. 26%, p= 0.046) and more frequent classification as AJCC category T1 (60% vs. 89% vs. 62%, p= 0.01). After follow-up of (57.2 vs. 68.2 vs. 51.7 months, p= 0.35), tumours arising from PAM had worse mean final visual acuity (20/50 vs. 20/40 vs. 20/40, p= 0.02) and greater frequency of visual acuity loss ≥3 lines (25% vs. 15% vs. 10%, p= 0.02). Kaplan–Meier estimates for 5-year risk showed no difference by tumour origin for visual acuity loss ≥3 lines, local tumour recurrence, exenteration, metastasis, or death. Conclusions: Conjunctival melanoma most often arose from PAM, and tumour origin did not affect clinical outcomes.

AbstractNeurocysticercosis is a parasitic infection caused by the larval stage of the pork tapeworm Taenia solium. Diagnostic criteria for neurocysticercosis are based on clinical manifestations, neuroimaging findings, and epidemiologic exposure. Treatment is tailored to acute symptoms. If increased intracranial pressure is present, then surgical intervention and/or corticosteroids may be used. If seizures are present, then antiepileptic drugs are used for therapy. Antiparasitic therapy is warranted for patients with viable and/or degenerating cysts in the brain parenchyma on neuroimaging. We present a case report of neurocysticercosis causing obstructive hydrocephalus requiring a ventriculoperitoneal shunt.

A review of 540 patients with conjunctival melanoma based on Fitzpatrick skin type (FST) revealed Type I (n = 126, 23%), Type II (n = 337, 62%), Type III (n = 56, 10%), Type IV (n = 8, 2%), Type V (n = 12, 2%), and Type VI (n = 1, <1%). The FST grading did not impact 5-year outcomes of tumor recurrence, exenteration, metastasis, or death.Supplemental Digital Content is available in the text.

Colloid deposition in granular media is relevant to numerous environmental problems. Classic filtration models assume a homogeneous pore space and largely ignore colloid aggregation. However, substantial evidence exists on the ubiquity of aggregation within porous media, suggesting that deposition is enhanced by it. This work studies the deposition process in relation to aggregate size and structure. We demonstrate that aggregation is induced at typical groundwater velocities by comparing the repulsive DLVO force between particle pairs to the hydrodynamic shear force opposing it. Column experiments imaged with high-resolution X-ray computed tomography are used to measure aggregate structure and describe their morphology probability distribution and spatial distribution. Aggregate volume and surface area are found to be power-law distributed, while Feret diameter is exponentially distributed with some flow rate dependencies caused by erosion and restructuring by the fluid shear. Furthermore, size and shape of aggregates are heterogeneous in depth, where a small number of large aggregates control the concentration versus depth profile shape. The range of aggregate fractal dimensions found (2.22–2.42) implies a high potential for restructuring or breaking during transport. Shear-induced aggregation is not currently considered in macroscopic models for particle filtration, yet is critical to consider in the processes that control deposition.

AbstractActinomycosis is an uncommon, chronic granulomatous disease caused by the filamentous, gram-positive bacterium Actinomyces israelii.It causes indolent, painful wound infections commonly presenting with oral-cervicofacial manifestations, but other infections of the chest wall and gastrointestinal and genital tract are also seen. A high level of suspicion is required for diagnosis, as it may be missed or mistaken for malignancy. Severe cases may involve the central nervous system and require surgical intervention. We present a case report of actinomycosis causing a brain abscess.

Carbapenem-resistant Gram-negative bacteria isolated in Venezuela have been poorly characterized. The present study characterized a total of 34 isolates obtained from 27 patients; five of these patients were multi-infected. The bacterial species identified were Klebsiella pneumoniae(17), Pseudomonas aeruginosa(9), and Acinetobacter baumannii(8). From these isolates, 85% were identified as carbapenemase-producing bacteria, and the identified carbapenemase genes were blaKPC-2(10/29 [34.4%]), blaVIM-type(7/29 [24.1%]), blaOXA-23(7/29 [24.1%]), blaNDM-1(8/29 [27.5%]), and the coexistence of blaOXA-23/blaNDM-1(2/29 [6.8%]). Patient 1 was multi-infected by K. pneumoniaeST11 and ST2413 isolates harbouring the blaNDM-1and blaKPC-2genes, respectively. The other patients were multi-infected by two or three different bacterial species such as ESBL-producing K. pneumoniaeisolates, P. aeruginosaharbouring the blaVIM-typegene, K. pneumoniaeST147 harbouring the blaKPC-2gene and by A. baumanniiharbouring the blaOXA-23gene. The blaNDM-1gene in A. baumanniiis flanked by an uncommon genetic structure, whereas blaNDM-1gene in K. pneumoniaerevealed a common structure described in different plasmids from Enterobacteriaceaeisolates. This study provides new information about the epidemiology of carbapenemase-producing bacteria in clinical setting in Venezuela.

AbstractBrucellosis is a zoonotic infection caused by the intracellular gram-negative bacterium Brucella.It is the most common zoonosis worldwide, and its transmission is classically associated with consumption of unpasteurized animal products. However, other mechanisms of transmission include contact of the skin or mucous membranes with infected animal tissue. We present a case of a patient who had more than one possible route of infection.

A superlattice approach for the atomic layer deposition of polycrystalline BaTiO3thin films is presented as an example for an effective route to produce high-quality complex oxide films with excellent thickness and compositional control. This method effectively mitigates any undesirable reactions between the different precursors and allows an individual optimization of the reaction conditions for the Ba–O and the Ti–O subcycles. By growth of nanometer thick alternating Ba(OH)2and TiO2layers, the advantages of binary oxide atomic layer deposition are transferred into the synthesis of ternary compounds, permitting extremely high control of the cation ratio and superior uniformity. Whereas the Ba(OH)2layers are partially crystalline after the deposition, the TiO2layers remain mostly amorphous. The layers react to polycrystalline, polymorph BaTiO3above 500 °C, releasing H2O. This solid-state reaction is accompanied by an abrupt decrease in film thickness. Transmission electron microscopy and Raman spectroscopy reveal the presence of hexagonal BaTiO3in addition to the perovskite phase in the annealed films. The microstructure with relatively small grains of ∼70 Å and different phases is a direct consequence of the abrupt formation reaction. The electrical properties transition from the initially highly insulating dielectric semiamorphous superlattice into a polycrystalline BaTiO3thin film with a dielectric constant of 117 and a dielectric loss of 0.001 at 1 MHz after annealing at 600 °C in air, which, together with the suppression of ferroelectricity at room temperature, are very appealing properties for voltage tunable devices.

AbstractThe cribriform-morular variant of papillary thyroid carcinoma (CMV-PTC) is an uncommon variant of papillary thyroid carcinoma. CMV-PTC can be associated with familial adenomatous polyposis (FAP), an autosomal-dominant polyposis syndrome caused by a mutation in the APCgene that leads to a disruption of the Wnt/beta-catenin pathway. Understanding the relation between CMV-PTC and FAP is a diagnostic tool for both pathologists and clinicians, because FAP has several implications for patients and their families.

La ecografía Point-of-Care (POCUS) es una herramienta sensible y específica para diagnosticar de manera precoz la patología del diafragma en pacientes críticos. Presentamos un caso clínico de un paciente con antecedentes de hernia diafragmática iatrogénica que ingresó en la Unidad de Reanimación tras una laparotomía exploradora de emergencia. Aprovechando el diagnóstico conocido de hernia diafragmática, describimos los signos clínicos que debemos encontrar en la evaluación POCUS para establecer el diagnóstico de hernia diafragmática: (1) fracción de acortamiento diafragmático normal bilateral; (2) excursión diafragmática reducida; y (3) posición cefálica de la cúpula diafragmática (4) mayor en supino que en sedestación. Igualmente, proponemos una sistemática de exploración ecográfica del diafragma y una clasificación diferencial de la disfunción diafragmática evaluada mediante POCUS en función de la correcta integridad y funcionamiento del músculo periférico y del tendón central diafragmáticos en el paciente crítico.

This article identifies the top 40 most influential environmental conflict cases in the US while also showcasing innovative mixed methods for more rigorous participatory collaborative work on environmental conflicts. University of Michigan students and faculty collaborated with Environmental Justice Organizations, Liabilities and Trade (EJOLT), a European Union mapping initiative, to identify US cases for their wider study. We began with an intensive scholarly and media literature review, combined with results from 31 semi-structured interviews with informants from a broad database of US environmental justice (EJ) departments, initiatives, and symposia. We then wrote short descriptions of 90 EJ conflict cases in US history, incorporating them into a detailed participatory online survey to garner expert and public input on which of them have been the most influential in shaping US popular opinion, policy, and political will on EJ issues. Seeking to provide a rigorous basis for the EJOLT mapping exercise, but also to instill an ethic of knowledge co-creation within the US Environmental Protection Agency (EPA)’s mechanisms for assessing EJ issues, we distributed the survey widely and posted it on the EPA's EJ Blog. It received over 1000 hits in the first two weeks. Our surveys remained active for about three weeks, for a total of 350 responses (101 from respondents who self-identified as EJ experts, and 249 from those identifying as members of the wider public). After eliminating incomplete or duplicate responses, we weighted to correct for that imbalance in the numbers, considering a total of 165 in our analysis. These responses comprise the list of 40 cases (unranked) we launched on the atlas in March 2014, and describe in this paper; the top five including multiple oil- or petroleum-based cases, one clean water case, one climate change case, and one confined animal feeding operation case.

Supplemental Digital Content is available in the text.

Describir la implantación de un robot para la elaboración de antineoplásicos en el Servicio de Farmacia y evaluar el valor añadido al proceso farmacoterapéutico.

Little information is available describing the epidemiology and clinical characteristics of those <12 months hospitalized with influenza, particularly at a population level.

Electroluminescence (EL) in scanning tunneling microscopy (STM), which enables spectroscopy with submolecular spatial resolution, is shown to be due to radiative ionization with vibronic shape resonances that carry Fano line profiles. Since Fano progressions retain phase information, the spectra can be transformed to the time domain to reconstruct the vibronic motion. In effect, measurements within a molecule are accessible with joint space–time resolution at the Å–fs limit. We demonstrate this through EL-STM on the Jahn–Teller-active Zn-etioporphyrin radical anion and visualize the orbiting motion of scattered electrons upon sudden reduction and oxidation. We discuss the elements that enable spectroscopy with submolecular spatial resolution through EL-STM and the closely related STM-Raman process.

Objective: Paravalvular leak (PVL) is a known and undesirable complication of prosthetic valve replacement. The presence of significant PVL is associated with comorbidities such as hemolysis, heart failure, and decreased long-term survival. The role of intraoperative transesophageal echocardiography (IOTEE) is the standard of care for valve repair surgery. However, its use in valve replacement is not universal.Methods: We performed a retrospective analysis of Aortic Valve Replacement (AVR) surgeries with IOTEE, from 2018-2020. Primary outcomes were the incidence of intraoperative PVL pre and post echocardiography guided correction. Secondary outcomes were PVL predictors factors, cardiopulmonary bypass time and cross clamp time. PVL was defined, according to circumferential extent of the regurgitant jet, as mild (<10%), moderate (10-20%) and severe (>20%). A PVL greater than mild was considered significant.Results: A total of 194 patients underwent surgical AVR (table 1); 73(37.6%) underwent minimally invasive aortic valve replacement and 121(62.4%) conventional aortic valve replacement. Of them, 87(4.8%) were isolated AVR and 107(55.1%) combined procedures. The overall incidence of significant PVL was 2.6% (n=5). All of them underwent echocardiography guided correction. Post correction IOTEE showed none significant PVL. Mild PVL was diagnosed in four of them. Cardiopulmonary bypass time was 119±37.9 minutes and cross clamp time was 81±26.1 minutes. There were no significant differences in these times between patients with PVL that needed correction and patients who did not. Diagnosis, etiology, bicuspid aortic valve, type of prosthesis and size number were not associated with PVL incidence.Conclusions: IOTEE allows early diagnosis of PVL. This enables intraoperative correction, without significant extension of surgical times, resulting in non-significant PVL. IOTEE should be the standard of care in AVR surgery.Table 1. Patients characteristicsPatients n194Age (Mean±SD)69.9 ± 11.4Sex n (%) Male, Female113(58.2%), 81(41.8)Diagnosis n (%)Aortic StenosisAortic InsufficiencyConcomitant stenosis and insufficiencyInfectious Endocarditis146 (76%)28 (14.6%)16 (8.3%)2 (1%)Etiology n (%)CalcificationRheumatic diseaseAnulectasisProlapseInfectious EndocarditisProsthetic DysfunctionFibroelastomaOthers160 (82.5%)3 (1.5%)6 (3.1%)10 (5.2%)6 (3.1%)2 (1%)2 (1%)5 (2.6%)Bicuspid valve n (%)31 (16.1%)NYHA Functional Class n (%)No Heart failureIIIIIIIV24 (13.6%)10 (5.6%)112 (63.3%)29 (16.4%)2 (1.1%)Angina76 (40.9%)Left Ventricle Ejection Fraction (LVEF) n (%)Normal>50%30-50%<30%143 (76.5)18 (9.6%)11 (5.9%)15 (8%)Euro Score II n (%)Low RiskIntermediate RiskHigh Risk173 (89.6%)19 (9.8%)1 (0.5%)

This article reviews the present status of the spin-foam approachto the quantization of gravity. Special attention is payed to the pedagogical presentation of the recently-introduced new models for four-dimensional quantum gravity. The models are motivated by a suitable implementation of the path integral quantization of the Plebanski formulation of gravity on a simplicial regularization. The article also includes a self-contained treatment of 2+1 gravity. The simple nature of the latter provides the basis and a perspective for the analysis of both conceptual and technical issues that remain open in four dimensions.

Metabolic syndrome (MetS) is associated with increased risk for cardiovascular disease (CVD). We examined the prevalence of and trends in MetS and its associated CVD risk factors in a nationally-representative sample of adolescents in the USA between 1999 and 2008.

By taking advantage of the tensor nature of surface-enhanced Raman scattering (SERS), we track trajectories of the linker molecule and a CO molecule chemisorbed at the hot spot of a nano-dumbbell consisting of dibenzyldithio-linked silver nanospheres. The linear Stark shift of CO serves as an absolute gauge of the local field, while the polyatomic spectra characterize the vector components of the local field. We identify surface-enhanced Raman optical activity due to a transient asperity in the nanojunction in an otherwise uneventful SERS trajectory. During fusion of the spheres, we observe sequential evolution of the enhanced spectra from dipole-coupled Raman to quadrupole- and magnetic dipole-coupled Raman, followed by a transition from line spectra to band spectra, and the full reversal of the sequence. From the spectrum of CO, the sequence can be understood to track the evolution of the junction plasmon resonance from dipolar to quadrupolar to charge transfer as a function of intersphere separation, which evolves at a speed of ∼1 Å/min. The crossover to the conduction limit is marked by the transition of line spectra to Stark-broadened and shifted band spectra. As the junction closes on CO, the local field reaches 1 V/Å, limited to a current of 1 electron per vibrational cycle passing through the molecule, with associated Raman enhancement factor viathe charge transfer plasmon resonance of 1012. The local field identifies that a sharp protrusion is responsible for room-temperature chemisorption of CO on silver. The asymmetric phototunneling junction, Ag–CO–Ag, driven by the frequency-tunable charge transfer plasmon of the dumbbell antenna, combines the design elements of an ideal rectifying photocollector.

To examine the association of cardiovascular (CV) comorbidities with the likelihood of being a stroke survivor and to determine the prevalence, treatment, and control of hypertension in this population.

Studies of inter-brain relationships thrive, and yet many reservations regarding their scope and interpretation of these phenomena have been raised by the scientific community. It is thus essential to establish common ground on methodological and conceptual definitions related to this topic and to open debate about any remaining points of uncertainty. We here offer insights to improve the conceptual clarity and empirical standards offered by social neuroscience studies of inter-personal interaction using hyperscanning with a particular focus on verbal communication.

To assess and plan future risk-analysis research projects, 275 documents describing methods and tools for assessing the risks associated with industrial machines or with other sectors such as the military, and the nuclear and aeronautics industries, etc., were collected. These documents were in the format of published books or papers, standards, technical guides and company procedures collected throughout industry. From the collected documents, 112 documents were selected for analysis; 108 methods applied or potentially applicable for assessing the risks associated with industrial machines were analyzed and classified. This paper presents the main quantitative results of the analysis of the methods and tools.

The current understanding of the quantum origin of cosmic structure is discussed critically. We point out that in the existing treatments a transition from a symmetric quantum state to an (essentially classical) non-symmetric state is implicitly assumed, but not specified or analysed in any detail. In facing this issue, we are led to conclude that new physics is required to explain the apparent predictive power of the usual schemes. Furthermore, we show that the novel way of looking at the relevant issues opens new windows from where relevant information might be extracted regarding cosmological issues and perhaps even clues about aspects of quantum gravity.

We consider the coupling between three-dimensional gravity with zero cosmological constant and massive spinning point particles. First, we study the classical canonical analysis of the coupled system. Then, we go to the Hamiltonian quantization generalizing loop quantum gravity techniques. We give a complete description of the kinematical Hilbert space of the coupled system. Finally, we define the physical Hilbert space of the system of self-gravitating massive spinning point particles using Rovelli's generalized projection operator which can be represented as a sum over spin-foam amplitudes. In addition we provide an explicit expression of the classical distance operator between two particles which is defined as an observable.

In this paper, we address the problem of the dynamics in three-dimensional loop quantum gravity with zero cosmological constant. We construct a rigorous definition of Rovelli's generalized projection operator from the kinematical Hilbert space-corresponding to the quantization of the infinite-dimensional kinematical configuration space of the theory-to the physical Hilbert space. In particular, we provide the definition of the physical scalar product which can be represented in terms of a sum over (finite) spin-foam amplitudes. Therefore, we establish a clear-cut connection between the canonical quantization of three-dimensional gravity and spin-foam models. We emphasize two main properties of the result: first that no cut-off in the kinematical degrees of freedom of the theory is introduced (in contrast to standard 'lattice' methods), and second that no ill-defined sum over spins ('bubble' divergences) are present in the spin-foam representation.

Abstract: We examine radiative corrections arising from Lorentz violating dimension five operators presumably associated with Planck scale physics as recently considered by Myers and Pospelov. We find that observational data result in bounds on the dimensionless parameters of the order 10–15. These represent the most stringent bounds on Lorentz violation to date.

Retinoic acid (RA) exerts beneficial effects on vascular remodelling and experimental nephritis, and plays a role in kidney development. Pathological changes caused by acute renal failure (ARF) result in high mortality. We determined whether RA ameliorates ARF-induced pathology caused by potassium dichromate (PD).

Tripeptidesserve as model systems for understanding the so-called random-coil state of peptides and proteins. While it is well known that polyproline or proline-rich polypeptides adopt the very regular polyproline-II (PPII) or left-handed 31-helix conformation, it was thus far not clear whether this is also the predominant structure adopted by proline-containing tripeptides. To clarify this issue, we have investigated the amide I' band profile in the ir, isotropic, and anisotropic Raman, and vibrational circular dichroism (VCD) spectrum of cationic and zwitterionic tri-proline in D2O. The data were analyzed by modifying a recently developed algorithm, which allows one to obtain the central dihedral angles of tripeptides from the amide I' band intensities (R. Schweitzer-Stenner, Biophysical Journal, 2002, Vol. 83, pp. 523–532). Our analysis revealed that the peptide adopts a nearly canonical PPII structure in water with ψ and φ values in the range of 175°–165° and −70°–(−80°), respectively. This is fully confirmed by the respective electronic ultraviolet-CD spectra. Our result indicates that the strong PPII propensity of trans proline results from local interactions between the pyrrolidine ring and the backbone and is not due to any long-range interactions. © 2003 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 71: 558–568, 2003

Tripeptidesserve as model systems for understanding the so‐called random‐coil state of peptides and proteins. While it is well known that polyproline or proline‐rich polypeptides adopt the very regular polyproline‐II (PPII) or left‐handed 31‐helix conformation, it was thus far not clear whether this is also the predominant structure adopted by proline‐containing tripeptides. To clarify this issue, we have investigated the amide I′ band profile in the ir, isotropic, and anisotropic Raman, and vibrational circular dichroism (VCD) spectrum of cationic and zwitterionic tri‐proline in D2O. The data were analyzed by modifying a recently developed algorithm, which allows one to obtain the central dihedral angles of tripeptides from the amide I′ band intensities (R. Schweitzer‐Stenner, Biophysical Journal, 2002, Vol. 83, pp. 523–532). Our analysis revealed that the peptide adopts a nearly canonical PPII structure in water with ψ and ϕ values in the range of 175°–165° and −70°–(−80°), respectively. This is fully confirmed by the respective electronic ultraviolet‐CD spectra. Our result indicates that the strong PPII propensity of trans proline results from local interactions between the pyrrolidine ring and the backbone and is not due to any long‐range interactions. © 2003 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 71: 558–568, 2003