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Topological insulators are insulators in the bulk but feature chiral energy propagation along the boundary. This property is topological in nature and therefore robust to disorder. Originally discovered in electronic materials, topologically protected boundary transport has since been observed in many other physical systems. Thus, it is natural to ask whether this phenomenon finds relevance in a broader context. We choreograph a dance in which a group of humans, arranged on a square grid, behave as a topological insulator. The dance features unidirectional flow of movement through dancers on the lattice edge. This effect persists when people are removed from the dance floor. Our work extends the applicability of wave physics to dance.

Cystic fibrosis (CF), an autosomal recessive disease, is caused by variants in both alleles of the CF transmembrane conductance regulator (CFTR) gene. A new assay based on allele-specific polymerase chain reaction and high-resolution melting analysis was developed for the detection of 18 CF-causing CFTR variants previously identified in Cuba and Latin America. The assay is also useful for zygosity determination of mutated alleles and includes internal controls. The reaction mixtures were normalized and evaluated using blood samples collected on filter paper. The evaluation of analytical parameters demonstrated the specificity and sensitivity of the method to detect the included CFTR variants. Internal and external validations yielded a 100% agreement between the new assay and the used reference tests. This assay can complement CF newborn screening not only in Cuba but also in Latin America., (© The Author(s) 2023. Published by Oxford University Press on behalf of American Society for Clinical Pathology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Conical intersections are ubiquitous in chemistry and physics, often governing processes such as light harvesting, vision, photocatalysis and chemical reactivity. They act as funnels between electronic states of molecules, allowing rapid and efficient relaxation during chemical dynamics. In addition, when a reaction path encircles a conical intersection, the molecular wavefunction experiences a geometric phase, which can affect the outcome of the reaction through quantum-mechanical interference. Past experiments have measured indirect signatures of geometric phases in scattering patterns and spectroscopic observables, but there has been no direct observation of the underlying wavepacket interference. Here we experimentally observe geometric-phase interference in the dynamics of a wavepacket travelling around an engineered conical intersection in a programmable trapped-ion quantum simulator. To achieve this, we develop a technique to reconstruct the two-dimensional wavepacket densities of a trapped ion. Experiments agree with the theoretical model, demonstrating the ability of analogue quantum simulators-such as those realized using trapped ions-to accurately describe nuclear quantum effects., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Most photochemistry occurs in the regime of weak light-matter coupling, in which a molecule absorbs a photon and then performs photochemistry from its excited state. In the strong coupling regime, enhanced light-matter interactions between an optical field and multiple molecules lead to collective hybrid light-matter states called polaritons. This strong coupling leads to fundamental changes in the nature of the excited states including multi-molecule delocalized excitations, modified potential energy surfaces, and dramatically altered energy levels relative to non-coupled molecules. The effect of strong light-matter coupling on covalent photochemistry has not been well explored. Photoswitches undergo reversible intramolecular photoreactions that can be readily monitored spectroscopically. In this work, we study the effect of strong light-matter coupling on the kinetics of photoswitching within optical cavities. Reproducing prior experiments, photoswitching of spiropyran/merocyanine photoswitches is decelerated in a cavity. Fulgide photoswitches, however, show the opposite effect, with strong coupling accelerating photoswitching. While modified merocyanine switching can be explained by changes in radiative decay rates or the amount of light in the cavity, modified fulgide switching kinetics suggest direct changes to excited-state reaction kinetics.

The study of molecular polaritons beyond simple quantum emitter ensemble models (e.g., Tavis-Cummings) is challenging due to the large dimensionality of these systems and the complex interplay of molecular electronic and nuclear degrees of freedom. This complexity constrains existing models to either coarse-grain the rich physics and chemistry of the molecular degrees of freedom or artificially limit the description to a small number of molecules. In this work, we exploit permutational symmetries to drastically reduce the computational cost of ab initio quantum dynamics simulations for large N . Furthermore, we discover an emergent hierarchy of timescales present in these systems, that justifies the use of an effective single molecule to approximately capture the dynamics of the entire ensemble, an approximation that becomes exact as N → ∞. We also systematically derive finite N corrections to the dynamics and show that addition of k extra effective molecules is enough to account for phenomena whose rates scale as 𝒪( N - k ). Based on this result, we discuss how to seamlessly modify existing single-molecule strong coupling models to describe the dynamics of the corresponding ensemble. We call this approach collective dynamics using truncated equations (CUT-E), benchmark it against well-known results of polariton relaxation rates, and apply it to describe a universal cavity-assisted energy funneling mechanism between different molecular species. Beyond being a computationally efficient tool, this formalism provides an intuitive picture for understanding the role of bright and dark states in chemical reactivity, necessary to generate robust strategies for polariton chemistry.

Objective: To evaluate the effect of polyunsaturated fatty acid-type omega 3 (ω3) on the temporomandibular joint (TMJ) of ovariectomized rats (OVX) with rheumatoid arthritis (RA)., Design: Rheumatoid arthritis was induced using complete Freund's adjuvant and type II bovine collagen injected at the base of the tail. Twenty-four adult female rats were treated by gavage and divided into four groups: G1: Sham, treated with 0.9% NaCl; G2: OVX, treated with 0.9% NaCl; G3: OVX+RA treated with 0.9% NaCl; G4: OVX+RA+ω3 treated with omega 3 (300 mg/kg/day). The induction of rheumatoid arthritis in groups G3 and G4 was performed 21 days after OVX, treatments were started 15 days after the induction of rheumatoid arthritis, maintained for 7 days, and killed. Bilateral TMJs were removed and assigned to morphometric analysis by micro-computed tomography and immunoassay to assess levels of cytokines IL-1β, IL-6, TNF-α, and IL-10., Results: Higher levels of inflammatory cytokines were found in the G2 and G3 (P < 0.05) and anti-inflammatory cytokines in the G1 and G4. TMJ analysis by micro-computed tomography showed a higher percentage of bone volume (median - interquartile deviation) in G1 (96.2-1.1) than in the G2 (91.5-2.0, P = 0.0374) and G3 (85.1-5.2, P = 0.0001) but showed no statistically significant differences with the G4 (93.1-1.7, P = 0.79)., Conclusions: Omega 3 successfully reduced TMJ damage in rats caused by ovariectomy and induced rheumatoid arthritis, and is a promising alternative for bone repair and attenuation of inflammatory processes., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Objective: We aim to describe the supraclavicular nerve's vascular entrapment by the external jugular vein as an unreported anatomical finding., Case Description: In a routine cadaveric dissection, the superficial emergence of the first division of the left supraclavicular nerve emerged along a duct formed through the external jugular vein. No other vascular or neural anatomical abnormalities were found in the surrounding structures., Conclusion: This unreported vascular entrapment of the supraclavicular nerve by the external jugular may harbour clinical implications for surgical and endovascular procedures on the external jugular vein and in refractory thoracic and scapular waist pain., (Copyright © 2020 The Author(s). Published by Elsevier Masson SAS.. All rights reserved.)

This study aimed to evaluate the effects of omega-3 (ω3) polyunsaturated fatty acids, in association with aspirin (AA), on the morphology of cytokine release in the temporomandibular joint (TMJ) of rats induced with rheumatoid arthritis (IR) by injecting 100 μL of complete Freund's adjuvant with bovine type II collagen at the tail base. Thirty-two adult male rats were divided into treatment groups: Sham, treated with 0.9% sodium chloride (NaCl) p.o.; IR-control, treated with 0.9% NaCl p.o.; IR-ω3 treated with ω3 PUFAS (85 mg/kg/day p.o.); and IR-ω3 + AA treated with ω3 (85 mg/kg/day p.o.) + AA (20 mg/kg/day i.p.). After maintained treatment for seven days, the animals were euthanized. Bilateral TMJs from each rat were removed and one was subjected to histological immunoassays and enzyme-linked immunosorbent assays to assess interleukin (IL)-1β, tumor necrosis factor-α, and IL-10 levels. Data analysis was performed using the Kruskal-Wallis and Dunn tests. In the IR-ω3 and IR-ω3 + AA groups, the TMJ was greater than in the IR-control group (P < 0.0001). The addition of AA did not improve the effects of ω3 (P = 0.0698). Similarly, the addition of AA conferred no additional effects on the cytokine levels (P > 0.05); however, it increased the proteoglycan density, compared with ω3 alone. We found that ω3 exhibited anti-inflammatory activity in arthritic rats, and the addition of AA increased proteoglycan density, but did not affect cytokine expression., (Copyright © 2021 Elsevier GmbH. All rights reserved.)

Background: Coronavirus disease 2019 (COVID-19) infection can cause alterations in the coagulation mechanism conditioning thrombotic phenomena such as acute limb ischemia (ALI) as the only manifestation of the infection. The aim of the study was to describe clinical and surgical characteristics of a group of patients infected with severe acute respiratory syndrome coronavirus 2 who presented ALI in the context of the COVID-19 pandemic at Lima, Peru., Methods: A multicenter, observational, and retrospective study was performed in six general hospitals, from March to July 2020. The variables considered were the pathological history and associated habits, laboratory tests, the severity of COVID-19 infection and ALI, the anatomic location of the lesion, treatment, evolution, and discharge conditions., Results: Thirty patients with ALI infected with COVID-19 were evaluated. Their mean age was 60 ± 15 years, the condition being more frequent in men (76.6%). The main comorbidities were arterial hypertension (33.3%), obesity (33.3%), and diabetes mellitus 2 (26.6%). There were 23.3% asymptomatic patients, and their only manifestation was ALI. Rutherford IIA and IIB stage included 93.2% of patients. The most frequent location of the thrombosis was the lower limbs (73.3% vs. 26.6%). Thrombectomy was performed in 76.6% of the patients, and amputation (primary and secondary) was performed in 30% of the patients. The mortality rate was 23.3%, all of it because of acute respiratory distress syndrome., Conclusions: ALI is a vascular pathology associated with embolic and thrombotic processes. COVID-19 infection can cause severe alterations in coagulation mechanisms, leading some patients to present severe acute arterial complications such as thrombosis, as the only associated manifestation. We report a younger cohort than those described in other studies and with a high frequency of amputations despite adequate surgical treatment., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Among the different biomarkers predicting response in chronic lymphocytic leukemia (CLL), the most influential parameters are the mutational status of the IGHV genes and the presence of TP53 gene disruptions. Nevertheless, these important assessments are not readily available in most centers dealing with CLL patients. To provide this molecular testing across the country, the Spanish Cooperative Group on CLL (GELLC) established a network of four analytical reference centers. A total of 2153 samples from 256 centers were analyzed over a period of 30 months. In 9% of the patients, we found pathological mutations in the TP53 gene, whereas 48.96% were classified as IGHV unmutated. Results of the satisfaction survey of the program showed a Net Promoter Score of 85.15. Building a national network for molecular testing in CLL allowed the CLL population a broad access to complex biomarkers analysis that should translate into a more accurate and informed therapeutic decision-making.

Quantum dynamics of the photoisomerization of a single 3,3'-diethyl-2,2'-thiacynine iodide molecule embedded in an optical microcavity was theoretically studied. The molecular model consisting of two electronic states and the reaction coordinate was coupled to a single cavity mode via the quantum Rabi Hamiltonian, and the corresponding time-dependent Schrödinger equation starting with a purely molecular excitation was solved using the Multiconfigurational Time-Dependent Hartree Method (MCTDH). We show that, for single-molecule strong coupling with the photon mode, nonadiabatic molecular dynamics produces mixing of polariton manifolds with differing number of excitations, without the need of counter-rotating light-matter coupling terms. Therefore, an electronic excitation of the molecule at the cis configuration is followed by the generation of two photons in the trans configuration upon isomerization. Conditions for this phenomenon to be operating in the collective strong light-matter coupling regime are discussed and found to be unfeasible for the present system, based on simulations of two molecules inside the microcavity. Yet, our finding suggests a new mechanism that, without ultrastrong coupling, achieves photon down-conversion by exploiting the emergent molecular dynamics arising in polaritonic architectures.

Glaucoma is a chronic, slowly progressing, and asymptomatic optic neuropathic disorder with a great variety of causes that involve gradual retinal ganglion cell axon loss. The disease is the second most common cause of blindness in the industrialized world. Once vision loss develops it is irreversible-although in many cases further loss can be slowed if adequate treatment is provided. If not treated, glaucoma can lead to complete vision loss in the affected eye. Primary open-angle glaucoma (POAG) is the most prevalent form of the disease in the industrialized countries, representing 94% of all glaucomas. In a Spanish study of 569 individuals, the prevalence of POAG was 2.1% (99% confidence interval 1.9%-2.3%) in the age range between 40 and 79 years. Assessing glaucomatous damage progression remains one of the most important and challenging aspects in glaucoma management. In addition, a better understanding of clinical risk factors for glaucoma worsening may help us to develop new strategies to improve glaucoma care. Over the past 2 decades, many studies have addressed the issue of risk factors associated with or predicting for glaucoma progression. Although many studies have attempted to identify the prognostic factors capable of predicting the course of POAG, the results have been varied and in some cases contradictory, and are thus of scant practical utility. This study was designed to evaluate the methodologic quality of the studies published in the literature on the prognostic factors for POAG progression measured by visual field deterioration.

Variations in microbial activity during the aerobic digestion of sludge generated at wastewater treatment plants were studied. Results obtained by the measurement of enzymatic activity and microbiological parameters were compared with those determined by traditional methods (COD, suspended solids, etc.). Their variation with digestion time was monitored for batch digestion over a period of 135 days. The relationship between these measurements and control parameters of the sludge was also investigated. It was found that the traditional physicochemical and microbiological parameters present a series of problems which detract from their usefulness. The enzymatic parameters dehydrogenase activity (primary metabolism) and esterase activity (secondary metabolism) are better able to characterise the process, and the ratio of these two variables may be used to estimate the degree of endogenesis and, consequently, the degree of stability of the aerobic sludge digestion. In addition, these techniques are swift and simple to employ.

A comparison between two analytical techniques is presented using trans-resveratrol as analyte and vine leaf as sample. The employed methods were: (a) laser desorption followed by resonance enhanced multiphoton ionization coupled with time-of-flight mass spectrometry (LD-REMPI-TOFMS), and (b) reversed-phase high performance liquid chromatography (RP-HPLC) with fluorescence detection. While both techniques show a similar range of linearity and reproducibility, marked differences were found in their sensitivity and required time for a single analysis. For example: (i) the chromatographic method required considerable less time (30min) than the REMPI method to implement the analysis, (ii) the detection and quantification limits of the REMPI technique were 2.1 and 6.7 microg L(-1), respectively, while for the chromatographic method they were ten times minor, i.e. 20 and 67 microg L(-1), respectively. A critical assessment including advantages and drawbacks of each technique is presented.

There is an apparent paradox between the benefits of aerobic exercise and the potentially deleterious effects of increased free radicals and decreased circulating antioxidants generated during exercise. To assess the oxidative/antioxidative status in competitive cyclists and ex-cyclists, we measured two markers not well studied in these situations, serum total antioxidant status (TAS) and antibodies against oxidized LDL (AuAb-ox-LDL) in 18 competitive male cyclists, 10 ex-competitive cyclists and 14 healthy males. AuAb-ox-LDL was evaluated by enzyme immunoassay, and serum TAS concentration was analyzed by spectrophotometry. Ex-cyclists had serum TAS levels statistically higher than the control group and cyclists group (p = 0.001 and p < 0.001, respectively). Active sportsmen showed significantly less AuAb-ox-LDL than healthy sedentary males, while there was a non-significant trend in the ex-cyclists to have lower AuAb-ox-LDL than the corresponding control group. AuAb-ox-LDL levels were not statistically different between the groups of active and previously active sporting men. There was a positive correlation between TAS and LDL-cholesterol in active cyclists under heavy training. In the ex-cyclist group, there was a negative correlation between serum TAS and the time elapsed since they had ended the competition. Competitive cycling decreases AuAb-ox-LDL levels, suggesting that it may decrease ox-LDL levels. After ending physical training, antioxidative status remains increased for at least one year, but the effect on AuAb-ox-LDL levels is lost.

Aberrant right subclavian arteries occur in as much as 2% of the population. Aneurysms in this vessel are rare but exhibit a marked propensity toward rupture; therefore, early elective treatment is indicated. Transluminally placed stent-grafts offer an alternative approach to the standard surgical treatment. This type of procedure is less invasive, with less attendant risk than operative repair. Because there was no proximal neck between the aneurysm and Kommerell diverticulum in the case described herein, it was decided to perform endovascular exclusion of the aneurysm by inserting an endoprosthesis to occlude the aortic exit of the aneurysm, combined with distal ligation. A bilateral carotid/subclavian bypass was also created to preserve the function of both subclavian arteries.

Toxic and cytotoxic activities of the toxic plant Elaeoselinum foetidum (Apiaceae) were evaluated using the brine shrimp toxicity (BST) and KB cell cytotoxicity assays. The active chloroform extract was subjected to a bioactivity-directed fractionation, monitored by the BST assay, that led to the isolation of the diterpenoid ent-kaur-16-en-19-oic acid. This compound was potent against the brine shrimp (LC(50) = 4.8 microg/mL) and KB cells (IC(50) = 1.6 microg/mL)., (Copyright 2002 John Wiley & Sons, Ltd.)