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Background: Though proposed by Lake and Yeoh in 1978 for vulcanized rubber characterization and possessing unique advantages with respect to traditional fracture characterization approaches, the Y-shaped cutting technique has been applied to a limited number of materials. Objective: This limited implementation may be due to researchers' unfamiliarity with the effects of Y-shaped cutting conditions and technique limitations, as well as a lack of standards. This review and best practices guide aims to provide a detailed road-map of the capabilities of Y-shaped cutting, with guidance for designing, executing, and interpreting its results. Method: By performing Y-shaped cutting at a constant blade propagation rate, fracture initiation effects encountered in many 'tearing' tests are bypassed. Meanwhile, unlike other contact-driven fracture conditions (needle insertion or cutting), the 'leg' separation renders the cutting nearly 'frictionless' under a variety of conditions. Results: Y-shaped cutting possesses two unique attributes. Under certain conditions (Zhang and Hutchens in Soft Matter 17(28):6728–6741, 2021), it can yield a fracture energy independent of sample and cutting implement geometry. In contrast to soft solid crack blunting, cutting reduces both the finite stretch and failure process zones to within a field of view readily imaged on a microscope, useful for microstructural studeis. To facilitate access to the above advantages, we summarize experimental variables and their role the fracture response and/or successful cutting and establish a pseudo-standard using silicone. Conclusion: This overview and recommendations empowers researchers to implement this highly-tunable cutting method in order to provide insights into other classes of materials in the future. [ABSTRACT FROM AUTHOR]

Introduction: Vernal Keratoconjunctivitis (VKC) is a chronic ocular condition affecting school-age children, particularly in hot, allergen-rich regions. It presents with symptoms such as intense itching, tearing, foreign body sensation, and sticky discharge, causing discomfort and management challenges in resource-limited settings. VKC impacts public health significantly due to its high prevalence and effect on academic performance and school attendance. Method: This cross-sectional study included 1521 school children aged 6 to 16 years in Western Uttar Pradesh. Comprehensive eye examinations were conducted, and VKC was diagnosed based on conjunctival and limbal papillae. A structured questionnaire collected data on socio-demographic factors, medical care access, and VKC's impact on daily life and school attendance. Descriptive statistics and Pearson chi-square tests were used for analysis. Result: Of the participants, 242 (15.9%) had VKC, with a higher prevalence among boys (56.2%). Most cases were mild (66%), with 34% severe. Symptoms included itching, stinging, tearing, photophobia, and discharge. Severe VKC resulted in higher rates of constant eye rubbing and tear production. School absenteeism was significantly higher in severe cases (78%) compared to mild cases (47%) (P<0.001). Severe VKC also led to more frequent medical consultations (52% vs. 22%, P=0.01). Conclusion: VKC significantly affects school attendance and medical care utilization among children in Western Uttar Pradesh. Improved management practices, better access to medical care, and enhanced support systems are essential for affected children and families. [ABSTRACT FROM AUTHOR]

Background: No widely accepted, validated instrument currently exists to measure clinical outcomes in patients who undergo dacryocystorhinostomy (DCR) for treatment of epiphora. Objective: To develop a patient-reported outcome measure applicable to this population. Methods: Psychometric evaluations, consultation with experts, and review of the literature informed item generation of a 12-question questionnaire to incorporate the most relevant symptoms experienced by patients with nasolacrimal duct obstruction. This questionnaire, known as the Tearing Assessment and Rating Scale-12 (TEARS-12), was administered to 32 patients before and after intervention, in the form of endoscopic DCR. Statistical analysis was performed to measure internal consistency, responsiveness, and test-retest reliability. Results: Pre-operative and post-operative TEARS-12 scores (28.2 [standard error (SE) 3.19] vs 11.8 [SE 3.25], respectively, P = 0.001) demonstrated improved patient outcome within 6 weeks following endoscopic DCR. Cronbach's alpha for the questionnaire was 0.90, indicating high overall reliability. Additionally, each question demonstrated internal reliability, with a corrected item-total correlation greater than 0.30. The intraclass correlation between the two pre-operative scores was 0.858 (P < 0.001), indicating high test-retest reliability. Conclusion: TEARS-12 is a statistically valid, easy-to-administer instrument to measure clinical outcomes in patients who undergo endoscopic DCR. [ABSTRACT FROM AUTHOR]

Purpose: The effects of episiotomy and second-degree tears on postpartum sexual function are key areas of enquiry in women's health research. Episiotomy and second-degree tears are common procedures and injuries that occur during childbirth. Understanding their impact on post-childbirth sexuality is crucial to women's overall well-being. This study aimed to examine the relationship between episiotomy, second-degree tears, and post childbirth sexuality. Methods: A cross-sectional design was employed, including 83 women who gave birth to Cáceres in 2017. Participants were evaluated based on sociodemographic and sexual health factors. Results: No significant differences were found in dyspareunia or sexual function between women who underwent episiotomies and those with second-degree tears. However, women who underwent episiotomies waited longer before resuming sexual activity after childbirth. Factors such as age, number of previous births, employment status, educational level, and breastfeeding status affected the timing and frequency of postpartum sexual activity. Conclusion: Dyspareunia negatively affects various aspects of sexual function. When comparing episiotomy and second-degree tears, their impacts on postpartum sexual function were similar. However, episiotomy delays the resumption of sexual activity. Sociodemographic factors significantly influence postpartum sexual health. These findings highlight the importance of individualised interventions and support for new mothers during the postpartum period to address potential sexual health concerns. [ABSTRACT FROM AUTHOR]

Copyright of Advanced Textile Technology is the property of Zhejiang Sci-Tech University Magazines and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Vernal Keratoconjunctivitis (VKC) is a chronic ocular condition affecting school-age children, particularly in hot, allergen-rich regions. It presents with symptoms such as intense itching, tearing, foreign body sensation, and sticky discharge, causing discomfort and management challenges in resource-limited settings. VKC impacts public health significantly due to its high prevalence and effect on academic performance and school attendance. Method: This cross-sectional study included 1521 school children aged 6 to 16 years in Western Uttar Pradesh. Comprehensive eye examinations were conducted, and VKC was diagnosed based on conjunctival and limbal papillae. A structured questionnaire collected data on socio-demographic factors, medical care access, and VKC's impact on daily life and school attendance. Descriptive statistics and Pearson chi-square tests were used for analysis. Result: Of the participants, 242 (15.9%) had VKC, with a higher prevalence among boys (56.2%). Most cases were mild (66%), with 34% severe. Symptoms included itching, stinging, tearing, photophobia, and discharge. Severe VKC resulted in higher rates of constant eye rubbing and tear production. School absenteeism was significantly higher in severe cases (78%) compared to mild cases (47%) (P

Copyright of China Mechanical Engineering is the property of Editorial Board of China Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose The aim of this study was to evaluate the prevalence of punctal stenosis in the patients presenting with eye watering due to obstructive epiphora. Patients and methods This descriptive, cross-sectional, prospective study included 75 eyes of 51 patients. The enrolled patients were classified into two groups; group 1 that included patients with punctal stenosis and group 2 that enrolled patients with obstructive epiphora due to other causes. Age subgrouping was performed to determine the prevalence of punctal stenosis among various age groups. Results The mean age of the patients was 52.32±16.19 years. Punctal stenosis was the most encountered cause of obstructive epiphora (32 patients=62.75%) in the study population. Punctal stenosis was also the most prevalent cause of obstructive epiphora (56.3%) in the oldest age subgroup (>60 years). Conclusion Punctal stenosis is the most common cause of obstructive epiphora in patients presenting with eye watering. Increasing age is the most important determinant of punctal stenosis.

Background: Short-lasting unilateral neuralgiform headache attacks (SUNHA) have the features of both short-lasting unilateral neuralgiform pain, such as trigeminal neuralgia or stabbing headache, and associated trigeminal autonomic symptoms, such as paroxysmal hemicrania or cluster headache. Recognizing and adequately treating SUNHA is essential but current treatment methods are ineffective in treating SUNHA. Methods: We reviewed the changes in the concept of short-lasting unilateral neuralgiform headache attacks and provide a narrative review of the current medical and surgical treatment options, from the first choice of treatment for patients to treatments for selective intractable cases. Results: Unlike the initial impression of an intractable primary headache disorder affecting older men, SUNHA affects both sexes throughout their lifespan. One striking feature of SUNHA is that the attacks are triggered by cutaneous or intraoral stimulation. The efficacy of conventional treatments is disappointing and challenging, and preventive therapy is the mainstay of treatment because of highly frequent attacks of a very brief duration. Amongst them, lamotrigine is effective in approximately two-third of the patients with SUNHA, and intravenous lidocaine is essential for the management of acute exacerbation of intractable pain. Topiramate, oxcarbazepine and gabapentin are considered good secondary options for SUNHA, and botulinum toxin can be used in selective cases. Neurovascular compression is commonly observed in SUNHA, and surgical approaches, such as neurovascular compression, have been reported to be effective for intractable cases. Conclusions: Recent advances in the understanding of SUNHA have improved the recognition and treatment approaches for this unique condition. [ABSTRACT FROM AUTHOR]

The role of TRPA1 in the thermosensitivity of the corneal cold thermoreceptor nerve endings was studied in young and aged mice. The contribution of the TRPA1-dependent activity to basal tearing and thermally-evoked blink was also explored. The corneal cold thermoreceptors' activity was recorded extracellularly in young (5-month-old) and aged (18-month-old) C57BL/6WT (WT) and TRPA1−/− knockout (TRPA1-KO) mice at basal temperature (34 °C) and during cooling (15 °C) and heating (45 °C) ramps. The blink response to cold and heat stimulation of the ocular surface and the basal tearing rate were also measured in young animals using orbicularis oculi muscle electromyography (OOemg) and phenol red threads, respectively. The background activity at 34 °C and the cooling- and heating-evoked responses of the cold thermoreceptors were similar in WT and TRPA1-KO animals, no matter the age. Similar to the aged WT mice, in the young and aged TRPA1-KO mice, most of the cold thermoreceptors presented low frequency background activity, a low cooling threshold, and a sluggish response to heating. The amplitude and duration of the OOemg signals correlated with the magnitude of the induced thermal change in the WT but not in the TRPA1-KO mice. The basal tearing was similar in the TRPA1-KO and WT mice. The electrophysiological data suggest that the TRPA1-dependent nerve activity, which declines with age, contributes to detecting the warming of the ocular surface and also to integrating the thermally-evoked reflex blink. [ABSTRACT FROM AUTHOR]

In situ fenestration of endovascular stent-grafts has become a mainstream bailout technique to treat complex emergent aneurysms while maintaining native anatomical visceral and aortic arch blood supplies. Fabric tearing from creating the in situ fenestration using balloon angioplasty may extend beyond the intended diameter over time. Further tearing may result from the physiologic pulsatile motion at the branching site. A resultant endoleak at the fenestrated sites in stent-grafts could ultimately lead to re-pressurization of the aortic sac and, eventually, rupture. In an attempt to address this challenge, plain woven fabrics were designed. They hold a specific corona surrounding a square-shaped cluster with a plain weave fabric structure, a 2/2 twill, or a honeycomb. The corona was designed to stop potential further tearing of the fabric caused by the initial balloon angioplasty and stent or later post-implantation motion. The cluster within the corona was designed with relatively loose fabric structures (plain weave, 2/2 twill weave, and honeycomb) to facilitate the laser fenestration. Two commercial devices, Anaconda (Vascutek, Terumo Aortic) and Zenith TX2 (Cook), were selected as controls for comparison against this new design. All the specimens were characterized by morphology, thickness, and water permeability. The results demonstrated that all specimens with a low thickness and water permeability satisfied the requirements for a stent graft material that would be low profile and resistant to endoleaks. The in situ fenestrations were performed on all fabrics utilizing an Excimer laser followed by balloon angioplasty. The fabrics were further observed by light microscopy and scanning electron microscopy. The dimension of the fenestrated apertures was smaller than the balloon's diameter. The tearing was effectively confined within the corona. The clinical acceptability of this concept deserves additional bench testing and animal experimentation. [ABSTRACT FROM AUTHOR]

The aluminum alloys belonging to the 7000 series are high-strength alloys used in a wide variety of products for weight reduction. They are primarily used in the field of transportation and aerospace. Among these, the A7075 alloy has the highest strength and is expected to be applicable in a wide range of fields, such as aircraft components and sports equipment. However, it has high deformation resistance and is prone to surface defects, which is called tearing. Tearing typically occurs at high temperatures and high ram speeds, and adversely affects productivity. The localized melting of Zn and additive compounds, due to the heat generated during the process, is considered to cause tearing. In this study, the effect of friction, heat, and tearing at the tool—metal interface was mitigated by improving the die surface quality. The reduced friction eliminated recrystallization by preventing the temperature from increasing to recrystallization temperature. In addition, an AlCrN coating was adopted instead of nitriding to improve the die surface quality. The tearing size and heat generated when using the AlCrN coating were found to be limited. Moreover, the grain size observed in the tearing region on the extruded surface was small. The simulations using the shear friction coefficient m observed from friction tests indicate that the use of the AlCrN coating improved the material flow. Thus, the AlCrN coating is considered effective for reducing friction at the interface and preventing the recrystallization of the extruded surface. From the aforementioned results, it can be inferred that a die coating can reduce the tearing sensitivity and increase the productivity of the A7075 alloy. [ABSTRACT FROM AUTHOR]

Abstract The aluminum alloys belonging to the 7000 series are high-strength alloys used in a wide variety of products for weight reduction. They are primarily used in the field of transportation and aerospace. Among these, the A7075 alloy has the highest strength and is expected to be applicable in a wide range of fields, such as aircraft components and sports equipment. However, it has high deformation resistance and is prone to surface defects, which is called tearing. Tearing typically occurs at high temperatures and high ram speeds, and adversely affects productivity. The localized melting of Zn and additive compounds, due to the heat generated during the process, is considered to cause tearing. In this study, the effect of friction, heat, and tearing at the tool—metal interface was mitigated by improving the die surface quality. The reduced friction eliminated recrystallization by preventing the temperature from increasing to recrystallization temperature. In addition, an AlCrN coating was adopted instead of nitriding to improve the die surface quality. The tearing size and heat generated when using the AlCrN coating were found to be limited. Moreover, the grain size observed in the tearing region on the extruded surface was small. The simulations using the shear friction coefficient m observed from friction tests indicate that the use of the AlCrN coating improved the material flow. Thus, the AlCrN coating is considered effective for reducing friction at the interface and preventing the recrystallization of the extruded surface. From the aforementioned results, it can be inferred that a die coating can reduce the tearing sensitivity and increase the productivity of the A7075 alloy.

Analyses of the DIII-D ITER Baseline Scenario database support that the disruptive m,n =2,1 magnetic islands are pressure gradient driven, non-linear instabilities seeded in a sequence of stochastic transient magnetic perturbations, and that the current profile relaxation does not affect the m,n =2,1 island onset rate. At low torque, these Neoclassical Tearing Modes are most commonly seeded by non-linear 3-wave coupling when the differential rotation between the q =1 & q =2 rational surfaces approaches zero. Lack of statistically significant difference between the current profiles of stable and unstable states, as well as lack of correlation between the tearing mode onset rate and the current profile relaxation both reject causality between the current profile evolution and the 2,1 magnetic island onsets in these plasmas. These support that preserving the differential rotation between the q =1 and q =2 rational surfaces is key to long pulse stable operation in the plasma scenario planned for ITER, while optimization of the current profile within the explored parameter space may lead to much weaker improvements than sustaining the differential rotation.

Several AISI type 321 stainless steel welded oil tank assemblies used on helicopter engine systems began to leak in service. One failure, a fracture on the aft side of a spot weld, was submitted for analysis. SEM fractography examination revealed fatigue failure. The failure initiated at an overload fracture near the root of the weld and was followed by mode III fatigue crack propagation (tearing) around the periphery of the weld. The initial overload fracture was caused by a high external load, which produced a concentrated stress and fracture at the weld root. The subsequent fatigue fracture was caused by engine vibrations during operation of the aircraft. Fracture characteristics indicated that the fatigue would not have occurred if the initial damage had not taken place. [ABSTRACT FROM AUTHOR]

A 79-year-old female with a history of keratoconjunctivitis sicca presented with several years of epiphora of both eyes. Thirteen years earlier, intracanalicular Herrick lacrimal plugs (Lacrimedics, Eastsound, WA, USA) had been placed in both eyes to treat her dry eye syndrome. After 13 years the patient felt the epiphora was intolerable and underwent endoscopic dacryocystorhinostomy (DCR) of the left, then the right side. Intraoperatively, during the right endoscopic DCR, a Herrick lacrimal plug was found in the common canaliculus into the lacrimal sac. Postoperatively, the patient did well with improved epiphora. The Herrick plug is designed to be intracanalicular, and this case illustrates that the plug can migrate and be retained for many years. Collared punctal plugs have a lower risk of this type of complication.

Background: The symptoms of ocular rosacea are often non-specific and there is no dependable diagnostic test for the disease, which may cause difficulties in diagnostics. The aim of this study was to examine the association between clinical findings of rosacea and self-reported ocular symptoms in a general population of middle-aged subjects. Methods: A clinical whole-body examination by a dermatologist was performed for 1,932 subjects belonging to the Northern Finland Birth Cohort 1966 Study. The presence of ocular symptoms was self-reported. The difference between rosacea and ocular symptoms was tested. Logistic regression analysis was used to identify associations between rosacea and ocular symptoms. Results: The prevalence of rosacea was 15.1% (n = 292); in the subjects with rosacea, erythematoteleangiectatic rosacea was found in 83.2% (n = 242), papulopustular in 15.4% (n = 45), ocular in 0.03% (n = 1), and phymatic in 0.1% (n = 3). Ocular symptoms in rosacea subjects were common, with dryness (32.3%), tearing (29.4%), foreign-body sensation (21.8%), and photophobia (20.5%) being the most common ones. Foreign-body sensation was reported significantly more often in those with rosacea compared to those without (p < 0.04). In logistic regression analyses, after adjusting, the subjects with rosacea had a 1.5-fold increased risk for decreased visual acuity in the dark (OR 1.48, 95% CI 1.01–2.14) compared to those without rosacea. Conclusion: Eye symptoms are common in subjects with rosacea. All patients with rosacea should be asked about ocular symptoms and both skin and eyelids should be examined even if the cutaneous findings are mild. [ABSTRACT FROM AUTHOR]

The role of TRPA1 in the thermosensitivity of the corneal cold thermoreceptor nerve endings was studied in young and aged mice. The contribution of the TRPA1-dependent activity to basal tearing and thermally-evoked blink was also explored. The corneal cold thermoreceptors’ activity was recorded extracellularly in young (5-month-old) and aged (18-month-old) C57BL/6WT (WT) and TRPA1−/− knockout (TRPA1-KO) mice at basal temperature (34 °C) and during cooling (15 °C) and heating (45 °C) ramps. The blink response to cold and heat stimulation of the ocular surface and the basal tearing rate were also measured in young animals using orbicularis oculi muscle electromyography (OOemg) and phenol red threads, respectively. The background activity at 34 °C and the cooling- and heating-evoked responses of the cold thermoreceptors were similar in WT and TRPA1-KO animals, no matter the age. Similar to the aged WT mice, in the young and aged TRPA1-KO mice, most of the cold thermoreceptors presented low frequency background activity, a low cooling threshold, and a sluggish response to heating. The amplitude and duration of the OOemg signals correlated with the magnitude of the induced thermal change in the WT but not in the TRPA1-KO mice. The basal tearing was similar in the TRPA1-KO and WT mice. The electrophysiological data suggest that the TRPA1-dependent nerve activity, which declines with age, contributes to detecting the warming of the ocular surface and also to integrating the thermally-evoked reflex blink.

In situ fenestration of endovascular stent-grafts has become a mainstream bailout technique to treat complex emergent aneurysms while maintaining native anatomical visceral and aortic arch blood supplies. Fabric tearing from creating the in situ fenestration using balloon angioplasty may extend beyond the intended diameter over time. Further tearing may result from the physiologic pulsatile motion at the branching site. A resultant endoleak at the fenestrated sites in stent-grafts could ultimately lead to re-pressurization of the aortic sac and, eventually, rupture. In an attempt to address this challenge, plain woven fabrics were designed. They hold a specific corona surrounding a square-shaped cluster with a plain weave fabric structure, a 2/2 twill, or a honeycomb. The corona was designed to stop potential further tearing of the fabric caused by the initial balloon angioplasty and stent or later post-implantation motion. The cluster within the corona was designed with relatively loose fabric structures (plain weave, 2/2 twill weave, and honeycomb) to facilitate the laser fenestration. Two commercial devices, Anaconda (Vascutek, Terumo Aortic) and Zenith TX2 (Cook), were selected as controls for comparison against this new design. All the specimens were characterized by morphology, thickness, and water permeability. The results demonstrated that all specimens with a low thickness and water permeability satisfied the requirements for a stent graft material that would be low profile and resistant to endoleaks. The in situ fenestrations were performed on all fabrics utilizing an Excimer laser followed by balloon angioplasty. The fabrics were further observed by light microscopy and scanning electron microscopy. The dimension of the fenestrated apertures was smaller than the balloon’s diameter. The tearing was effectively confined within the corona. The clinical acceptability of this concept deserves additional bench testing and animal experimentation.

To report a series of patients who developed punctal stenosis secondary to the use of topical netarsudil 0.02% for treatment of glaucoma. Case series. Patients using topical netarsudil for management of glaucoma and noted to have punctal stenosis ipsilateral to the eye(s) being treated with netarsudil were included. Each enrolled patient's chart was reviewed, and alternative causes of punctal stenosis were sought. Photographs were obtained to document punctal stenosis for some patients. Presence of punctal stenosis after topical netarsudil use and resolution of punctal stenosis after cessation of therapy. Sixteen patients had punctal stenosis; 13 developed unilateral punctal stenosis while using netarsudil unilaterally, and 3 patients developed bilateral punctal stenosis with bilateral use. Time from initiation of netarsudil to recognition of symptoms or documentation of punctal stenosis ranged from 2 to 35 months (median, 12; mean, 14.0 ± 8.7 months). Thirteen patients endorsed tearing, but 2 had no symptoms. Ectropion was seen in 1 eye. Corneal verticillata was noted in 14 patients (87.5%). In 8 cases, netarsudil was discontinued, and the punctal stenosis was reversed, with resolution of associated symptoms. Netarsudil use can lead to the development of reversible punctal stenosis. This inflammation-mediated stenosis may cause tearing and associated symptoms and may be of sufficient severity to necessitate discontinuation of treatment. In this case series, all patients who discontinued treatment had reversal of their punctal stenosis and associated symptoms. [ABSTRACT FROM AUTHOR]

The tearing resistance of blown polyethylene films is one of their most important performance characteristics, and yet remains one of the least understood. The present work concerns the development of a new approach to rigorously measuring tearing resistance in-situ while also quantifying the material mechanics underlying tearing, and the application of this new technique to tearing of metallocene-catalyzed linear-low density polyethylene blown films with either a high or low extent of locked-in processing-induced microstructural pre-orientation. An experimental/numerical framework, VDIC, was developed to measure tearing resistance and crack tip mechanics in-situ during tearing of tough polyethylene films, employing digital image correlation (DIC) mapping of the deformation process and post-processing of DIC data to calculate the stress tensor field, energy density field, and crack growth resistance curve (JR), utilizing a sophisticated constitutive model engine and expansive material model library previously developed for finite element analysis of polymers. This experimental/numerical framework obviates the need for finite element analysis (FEA) of fracture to calculate tearing resistance and crack tip stress fields—and in fact offers distinct advantages over FEA—including reduced sensitivity to model error, avoidance of simulation convergence challenges, and the elimination of the requirement to a priori impose a material failure model to study stable crack propagation. [ABSTRACT FROM AUTHOR]

Objective: There is value in understanding the common etiologies of epiphora within different patient populations as well as identifying barriers to adequate treatment and symptom relief. The primary goal of the study is to report common etiologies of epiphora and the impact of treatment in patients of a large, inner-city hospital. Methods: This is a retrospective review of 10 years of data from the charts of 516 adult patients. The most common diagnoses and interventions linked to this symptom were evaluated. Subjective symptom improvement and adherence to follow-up were also analyzed. Results: Three hundred (58.1%) patients carried a diagnosis of dry eye syndrome and, of these, 40.1% did not have other ocular findings to explain their epiphora. Conservative management (CM) was recommended to the majority (86.4%) of the study population. 27.5% of the 357 patients who received CM as the only intervention reported symptom improvement. 90.1% of patients who underwent DCR reported symptom improvement. Nearly half of the patients were lost to follow-up. Conclusion: Epiphora is a common symptom that may be multifactorial in etiology, making effective treatment a challenge. Reflex tearing secondary to ocular surface dryness was the most common etiology linked to epiphora in this study. Low rates of follow-up limit the ability to fully assess the impact of current interventions on symptoms. Addressing the socioeconomic barriers that lower patient adherence to follow-up should allow more effective treatment of epiphora. [ABSTRACT FROM AUTHOR]

El autor expone el problema del pensamiento y la práctica del mundo occidental posmoderno, donde coinciden la violencia y el abandono de todo soporte natural de los valores. Para buscar una posible solución examina el concepto de “cuerpo”, que cambia de una sociedad a otra marcando el estilo de cada cultura. Traza su evolución hasta la primera mitad del siglo xx, cuando se sometió el cuerpo al mercado y se promovió la ideología de la muerte del sujeto. Califica como “desgarramiento del cuerpo” al actual deterioro físico y simbólico de los individuos y las sociedades. Propone como instrumento de cambio un concepto filosófico alternativo de “cuerpo”, que integra en un solo sistema los aspectos visibles e invisibles del ser humano, a fin de fundar los valores en una teoría dinámica de la naturaleza humana, que permita recuperar al “cuerpo que somos” en este siglo xxi. / The author exposes the problem of the thought and practice of the postmodern western world, where violence and the abandonment of all natural support of values coincide. To look for a possible solution, he examines the concept of “body”, which changes from one society to another, marking the style of each culture. It traces its evolution until the first half of the 20th century, when the body was submitted to the market and the ideology of the subject’s death was promoted. It qualifies as “tearing of the body” the current physical and symbolic deterioration of individuals and societies. It proposes as an instrument of change an alternative philosophical concept of “body”, which integrates in a single system the visible and invisible aspects of the human being, in order to found the values in a dynamic theory of human nature that allows to recover the “body that we are “ in this 21st century.

We report the first preemptive direct stabilization of $m,n = 2,1$ neoclassical tearing modes (NTMs) in DIII-D low-torque ITER baseline scenario plasmas by electron cyclotron waves. These experiments strongly support that the observed stabilization is achieved by replacing the missing bootstrap current in the island by electron cyclotron current drive (ECCD). These plasmas (with and without ECCD) are stable to 2,1 NTMs when the differential rotation between the q = 1 and q = 2 surfaces ( $\Delta f_{1,2}$ ) is sustained above a critical value ( $\Delta f_\textrm{CRIT}\approx1$ kHz), but those evolving to low differential rotation ( $\Delta f_{1,2}\lt \Delta f_\textrm{CRIT}$ ) routinely develop a disruptive 2,1 island at the time and frequency of a sawtooth precursor. Preemptive, local and direct stabilization by ECCD is tested by scanning the current drive amplitude and location inside and outside of the q = 2 rational surface shot by shot. Analysis of only low differential rotation time windows, i.e. when stabilization from $\Delta f_{1,2}$ is absent, shows focused ECCD at q = 2 prevents the onset of 2,1 NTMs. These results are important, as they give the first demonstration of disruptive NTM control by ECCD in the plasma scenario planned for ITER.

Analysis of a multi-scenario database of over 13 000 DIII-D H-mode discharges shows that the $m,n = 2,1$ magnetic islands are dominantly pressure gradient driven, stochastically triggered non-linear instabilities at all edge safety factor ( $q_\text{95}$ ) values. The instability onset time closely follows the exponential distribution in intermediate and high $q_\text{95}$ scenarios and is characterized by near constant onset rate ( λ ), in accordance with Poisson-point processes. This implies that the plasmas are operated in marginally stable conditions, characterized by a small threshold for instability growth and variations in the trigger amplitude and/or the stabilizing mechanisms with temporally uniform random distribution in this database. While the majority of the tearing modes occur in the first current-profile relaxation time of the $\beta_\text{N}$ flattop, constant λ throughout the $\beta_\text{N}$ flattop shows that the tearing onset is insensitive to the evolution of the equilibrium current profile. In low $q_\text{95}$ scenarios, where a large fraction of the plasmas are operated at low torque, λ increases over the course of the $\beta_\text{N}$ flattop, showing that these plasmas evolve toward more unstable conditions. The onset rate rapidly increases with $\beta_\text{N}$ , while it does not show a clear dependence on the current gradient at the mode rational surface. Overall, these observations support that the majority of the analyzed 2,1 tearing modes are non-linear, neoclassically driven instabilities and classical stability does not play a dominant role in their onset.

The structure of solution branches of the equation ε 2 u x x = u 3 − λ u + δ g (x) , for x ∈ R is studied, for real constants, ε , λ and δ , where g (x) is periodic in x and u satisfies Neumann boundary conditions. For α : = u (0) bifurcation structure in the α – δ plane occurs that for small ε leads to families of singular asymptotic solutions with interior transition layers between outer solutions. In contrast, bifurcation in the α – λ plane produces families of oscillatory solutions that for small ε have large numbers, n , of oscillations between envelope outer solutions. The n label of the solution branch is defined by its local bifurcation at ε 2 n 2 = λ > 0. Further the bifurcation structure on the n branch is classified by the integer n being either even or odd. When n is even the pitchfork bifurcation in the α – δ plane leads to connected branches of solutions in the α – λ – δ space. But when n is odd the presence of g (x) leads to cusp catastrophes (for small ε) in the α – δ plane and these give rise to disconnected (or isolated) branches of solution in the α – λ plane that appear to be torn from the main solution branch. The integer n acts as a count of the number of oscillations on these solution branches. As ε 2 λ − 1 → 0 we see layer behaviour occurring about the top and bottom outer solutions and as ε 2 λ − 1 → ∞ we find convergence to the middle outer solution. [ABSTRACT FROM AUTHOR]

Background: Radioiodine ablation is a frequent procedure for the management of thyroid cancer. In several cases, this treatment is followed by secondary acquired nasolacrimal duct obstruction (SALDO). Risk factors for the development of SALDO are not defined yet. Aim – to provide clinical and demographic characteristics of tearing in patients after radioiodine treatment. Materials and methods: Material was obtained by a phone survey of 588 patients who underwent radioiodine treatment. Age and gender of the respondent, strength of administered medication, and time since the end of treatment were taken into account. Patients were asked if they had dry mouth and/or tearing at the time of the survey. Differences in values were found using parametric and nonparametric criteria, Pearson's χ2 test. Differences were considered statistically significant at p ≤ 0.05. Results: Severe tearing was reported by 8.8% of patients after single-dose radioiodine treatment and 23.9% of patients after repeated one. The age of patients with severe tearing and without it showed statistically significant difference in patients after single-dose radioiodine treatment and no statistically significant difference in patients after repeated radioiodine treatment. Administration of 4 GBq or more in patients aged 61–71 years results in 4-fold increase of the risk of severe tearing. Dry mouth causes 3.6-fold increase of the risk of developing severe tearing. Conclusion: Finding risk factors for SALDO development after radioiodine therapy in the future will contribute to an individualized approach to the prevention of this complication. Development of preventive measures is one of the tasks facing researchers. [ABSTRACT FROM AUTHOR]

Perfluorohexyloctane (F6H8) eyedrops have been recently introduced in Europe as a product to treat dry eye disease, based on its ability to reduce tear film instability in Meibomian gland dysfunction and evaporative dry eye disease, although its mechanism of action is still unknown. In the present pilot study, we evaluated the effects of the ocular instillation of a single drop of commercial F6H8 eyedrops in 20 healthy humans (9 women/11 men), measuring: (a) Corneal surface temperature (CST) from infrared video images; (b) tear volume using phenol red threads; (c) blinking frequency; and (d) ocular surface sensations (cold, dryness, pricking, foreign body, burning, itching, gritty, eye fatigue, watering eyes, and light-evoked discomfort sensations; scored using 10 cm Visual Analog Scales), before and 5–60 min after F6H8 or saline treatment. CST decreased and tearing and blinking frequency increased significantly after F6H8 but not after saline solution. When applied unilaterally, CST decreased only in the F6H8-treated eye. No sensations were evoked after F6H8 or saline. The corneal surface temperature reduction produced by topical F6H8 does not evoke conscious ocular sensations but is sufficient to increase the activity of corneal cold thermoreceptors, leading to an increased reflex lacrimation and blinking that may relieve dry eye condition thus reducing ocular discomfort and pain.

Aortic dissections progress, in part, by delamination of the wall. Previous experiments on cut-open segments of aorta demonstrated that fluid injected within the wall delaminates the aorta in two distinct modes: stepwise progressive tearing in the abdominal aorta and a more prevalent sudden mode of tearing in the thoracic aorta that can also manifest in other regions. A microstructural understanding that delineates these two modes of tearing has remained wanting. We implemented a phase-field finite-element model of the aortic wall, motivated in part by two-photon imaging, and found correlative relations for the maximum pressure prior to tearing as a function of local geometry and material properties. Specifically, the square of the pressure of tearing relates directly to both tissue stiffness and the critical energy of tearing and inversely to the square root of the torn area; this correlation explains the sudden mode of tearing and, with the microscopy, suggests a mechanism for progressive tearing. Microscopy also confirmed that thick interlamellar radial struts are more abundant in the abdominal region of the aorta, where progressive tearing was observed previously. The computational results suggest that structurally significant radial struts increase tearing pressure by two mechanisms: confining the fluid by acting as barriers to flow and increasing tissue stiffness by holding the adjacent lamellae together. Collectively, these two phase-field models provide new insights into the mechanical factors that can influence intramural delaminations that promote aortic dissection. [ABSTRACT FROM AUTHOR]

This paper presents a method for adaptive fracture propagation in thin sheets. A high-quality triangle mesh is dynamically restructured to adaptively maintain detail wherever it is required by the simulation. These requirements include refining where cracks are likely to either start or advance. Refinement ensures that the stress distribution around the crack tip is well resolved, which is vital for creating highly detailed, realistic crack paths. The dynamic meshing framework allows subsequent coarsening once areas are no longer likely to produce cracking. This coarsening allows efficient simulation by reducing the total number of active nodes and by preventing the formation of thin slivers around the crack path. A local reprojection scheme and a substepping fracture process help to ensure stability and prevent a loss of plasticity during remeshing. By including bending and stretching plasticity models, the method is able to simulate a large range of materials with very different fracture behaviors. Copyright © ACM.