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For decades, researchers have been exploring pattern-forming instabilities in free surface thin films in the hope of developing alternative lithographic techniques for applications only requiring resolution limits in the submicron range. Previous studies have shown how the pitch and shape of elements in an array can be varied by adjusting the magnitude of surface forces and growth time prior to solidification in situ. Since the formations emerge naturally from an initial flat molten film, the final arrays exhibit ultrasmooth interfaces and are therefore ideally suited to beam-shaping applications such as thin-film micro-optics. Progress in this field has stalled, however, due to the very nature of the formation process. Even when great care is taken to ensure that initial films are defect-free, final arrays still exhibit unacceptable variability in pitch, shape, and height due to ubiquitous sources of noise responsible for instability and growth. In this work, we focus on a thermocapillary instability in slender molten films exposed to a very large thermal gradient. We begin with a discussion and demonstration of why this instability inextricably leads to highly disordered arrays even if initialized by a film with very small amplitude surface roughness. We then demonstrate how spatially periodic modulation of the thermal field, implemented in three different ways, can induce synchronous growth of highly uniform periodic arrays despite noisy initial conditions. Results based on linear and weakly nonlinear stability analysis, Bloch wave analysis, and direct numerical simulation of the interface equation reveal how resonant wavelength excitations occurring between the modulation and instability driving fields are responsible for such rapid and coherent growth. An additional benefit is that the modulation field can be selected to yield an array pitch much smaller than in unmodulated systems.

Hepatocellular carcinoma (HCC) is a leading cause of death, resulting in over 700 thousand deaths annually worldwide. Chemotherapy is the primary therapeutic strategy for patients with late-stage HCC. Heteronemin is a marine natural product isolated from Hippospongia sp. that has been found to protect against carcinogenesis in cholangiocarcinoma, prostate cancer, and acute myeloid leukemia. In this study, heteronemin was found to inhibit the proliferation of the HCC cell lines HA22T and HA59T and induce apoptosis via the caspase pathway. Heteronemin treatment also induced the formation of reactive oxygen species (ROS), which are associated with heteronemin-induced cell death, and to trigger ROS removal by mitochondrial SOD2 rather than cytosolic SOD1. The mitogen-activated protein kinase (MAPK) signaling pathway was associated with ROS-induced cell death, and heteronemin downregulated the expression of ERK, a MAPK that is associated with cell proliferation. Inhibitors of JNK and p38, which are MAPKs associated with apoptosis, restored heteronemin-induced cell death. In addition, heteronemin treatment reduced the expression of GPX4, a protein that inhibits ferroptosis, which is a novel form of nonapoptotic programmed cell death. Ferroptosis inhibitor treatment also restored heteronemin-induced cell death. Thus, with appropriate structural modification, heteronemin can act as a potent therapeutic against HCC.

Background Studies on the association between polymyositis/dermatomyositis (PM/DM) and acute respiratory failure (ARF) are considerably limited. We investigated whether ARF is associated with PM/DM using a nationwide cohort study. Methods We identified 1,374 patients with newly diagnosed PM/DM and 13,740 comparison individuals without PM/DM (non-PM/DM) randomly selected from the general population; frequency matched by age, sex, and index year using the National Health Insurance Research Database; and followed up until the end of 2011 to measure the incidence of ARF. Cox proportional hazards regression analysis was used to measure the hazard ratio (HR) of ARF for the PM/DM cohort in comparison with the non-PM/DM cohort. Results The adjusted HR of ARF was 5.05 for the PM/DM cohort compared with the non-PM/DM cohort after adjusting for sex, age, comorbidities, Charlson comorbidity index (CCI) score and medicine. The risk of ARF significantly increased irrespective of age, sex, comorbidities and medicine. Meanwhile, the PM/DM cohort with comorbidities, such as cardiac disease (hypertension), pulmonary disease (chronic obstructive pulmonary disease and pneumonia), and pulmonary vascular diseases had additive effects on the incident ARF. Conclusions This study determined the cross-reaction of pulmonary heart disease in the PM/DM cohort with incident ARF even without comorbidities.

Background Wrong-site surgeries (including wrong-site, wrong-person and wrong-procedure errors) remain the number one problem among adverse events of health care delivery. Patients and/or family members should be involved when possible to help prevent such errors. Aims 1) Design an educational animation program about patient safety for patients and/or family members to help eliminate wrong-site surgery errors. 2) Evaluate its educational effect. Methods The animation developed for this study includes an introduction, hypothetical story, and guided information, and was presented at a tertiary medical center in northern Taiwan. A single-group pretest and posttest design was used. Results Forty-six patients and 48 family members participated in the study. The pre-training score was 3.6 (on a scale of 1–4). After watching the animation, there was no significant increase (0.08 ± 0.5) for the patient group, but the family member group showed significant improvement (0.21 ± 0.6, P = .0309). Most participants (98.9%) were satisfied with the animation. Conclusion The majority of participants reported good practices for avoiding wrong-site surgery mistakes before an operation. A significant improvement of post-training scores in the family member group was seen. The high satisfaction rating given by the participants after seeing the animation indicates that it was generally acceptable.

Among 176 patients who had had severe acute respiratory syndrome (SARS), SARS-specific antibodies were maintained for an average of 2 years, and significant reduction of immunoglobulin G-positive percentage and titers occurred in the third year. Thus, SARS patients might be susceptible to reinfection >or=3 years after initial exposure.

The inhomogeneous differential equation x″ + sinx = δ sin(t + t0)/ϵ describes the motion of a sinusoidally forced pendulum. The orbits that connect the two saddle points of the unforced (δ = 0) pendulum are called separatices. If ϵ = O (1) , then one can use Melnikov's method to show that these separatrices can split for weak forcing (δ ⪡ 1), and that the perturbed motion is chaotic. If ϵ ⪡ 1, Melnikov's method fails because the perturbation term is not analytic in ϵ at ϵ = 0. In this paper we show that for δ ⪡ 1 and ϵ ⪡1, the solution of the perturbed problem exhibits a symmetry to all orders in an asymptotic expansion. From the asymptotic expansion it follows that the separatrices split by an amount that is at most transcendentally small. This proof differs from that of Holmes, Marsden and Scheurle.