Nurses' Work Concerns and Disenchantment During the COVID-19 Pandemic: Machine Learning Analysis of Web-Based Discussions.

BACKGROUND: Web-based forums provide a space for communities of interest to exchange ideas and experiences. Nurse professionals used these forums during the COVID-19 pandemic to share their experiences and concerns. OBJECTIVE: The objective of this study was to examine the nurse-generated content to capture the evolution of nurses' work concerns during the COVID-19 pandemic. METHODS: We analyzed 14,060 posts related to the COVID-19 pandemic from March 2020 to April 2021. The data analysis stage included unsupervised machine learning and thematic qualitative analysis. We used an unsupervised machine learning approach, latent Dirichlet allocation, to identify salient topics in the collected posts. A human-in-the-loop analysis complemented the machine learning approach, categorizing topics into themes and subthemes. We developed insights into nurses' evolving perspectives based on temporal changes. RESULTS: We identified themes for biweekly periods and grouped them into 20 major themes based on the work concern inventory framework. Dominant work concerns varied throughout the study period. A detailed analysis of the patterns in how themes evolved over time enabled us to create narratives of work concerns. CONCLUSIONS: The analysis demonstrates that professional web-based forums capture nuanced details about nurses' work concerns and workplace stressors during the COVID-19 pandemic. Monitoring and assessment of web-based discussions could provide useful data for health care organizations to understand how their primary caregivers are affected by external pressures and internal managerial decisions and design more effective responses and planning during crises.

Ocular itch associated with allergic conjunctivitis: latest evidence and clinical management.

Allergic conjunctivitis is one of the most common allergic conditions worldwide. Its incidence is increasing due to changing climate, pollution, increased pollen loads, and the subject's heightened immunological sensitivity in response to these environmental changes. The pathophysiology predominantly involves immunoglobulin E-related mast-cell activation, with release of histamine and other mediators contributing to the propagation of the response by calling in other immune cells and further inflammation. This article presents the evolution of ocular allergy treatments, from vasoconstrictors, to antihistamines and mast-cell stabilizers, to the dual-acting agents, as well as corticosteroid and immunomodulatory options. Future targets for allergy treatment are also discussed.

Radiation damage on Langmuir monolayers of the anionic 1.2-dipalmitoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (sodium salt)(DPPG) phospholipid at the air-DNA solution interface.

The resilience of cells to ultraviolet (UV) irradiation is probably associated with the effects induced in biological molecules such as DNA and in the cell membrane. In this study, we investigated UV damage to the anionic 1.2-dipalmitoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (sodium salt) (DPPG) phospholipid, which is an important component of cell membranes. In films cast from DPPG emulsions, UV irradiation induced cleavage of C-O, C=O and -PO(2-) bonds, while in Langmuir monolayers at the air/water interface representing the cell membrane this irradiation caused the monolayer stability to decrease. When DNA was present in the subphase, however, the effects from UV irradiation were smaller, since the ionic products from degradation of either DPPG or DNA stabilize the intact DPPG molecules. This mechanism may explain why UV irradiation does not cause immediate cell collapse, thus providing time for the cellular machinery to repair elements damaged by UV.

Trends in prevalence and treatment of ocular allergy.

PURPOSE OF REVIEW: This review describes recent findings and trends in prevalence and treatment of allergic ocular diseases. Although the major focus is on seasonal and perennial allergic conjunctivitis, related disorders will also be considered. RECENT FINDINGS: Published reports from countries around the world suggest that the spectrum of atopic diseases, including seasonal and perennial allergic conjunctivitis, is continuing its pattern of increasing prevalence, which has been well documented over the past few decades. In addition, although treatment modalities have focused on topical formulations including antihistamines and corticosteroids, there is a significant emphasis on immunotherapy as an alternative treatment modality, particularly in the USA. SUMMARY: Allergic conjunctivitis is a key component in the spectrum of allergic diseases that is sometimes collectively referred to as rhinoconjunctivitis. Because of its high prevalence worldwide, it exacts an increasing toll in terms of patient discomfort, morbidity, and loss of productivity. Current estimates suggest that at least 20% of the overall population suffers from some form of allergic conjunctivitis, many without ever seeking treatments. In addition, a significant proportion of patients experience chronic forms of allergy that are less responsive to existing therapies. Recent approval of immunotherapy-based treatments may address this therapeutic gap.

DNA damage induced by carbon ions (C³âº) beam accessed by independent component analysis of infrared spectra.

PURPOSE: To understand the degradation processes and role of secondary species on deoxyribonucleic acid (DNA)-damaged fragments as a result of irradiation with energetic ions. MATERIALS AND METHODS: Damage caused to DNA thin films as a result of exposure to 4 keV carbon ions beam was accessed by analyzing the infrared spectra, obtained in situ for different irradiation times, with both bi-dimensional (2D) correlation spectroscopy and independent component analysis (ICA). RESULTS: Results indicated that deoxyribose, phosphate and base groups of the DNA molecule were being damaged and new reaction products as oxime and furfural groups are being formed. CONCLUSIONS: Damage on DNA bases is consistent with the formation of oxime products which react with DNA deoxyribose products forming furfural groups and confirming that DNA damage is caused by direct and indirect processes.

Characterization of PAH/DPPG layer-by-layer films by VUV spectroscopy.

The spectroscopic characterization of layer-by-layer (LbL) films containing liposomes is essential not only for determining the precise film architecture but also to guide the design of drug delivery systems. In this study we provide the first report of vacuum ultraviolet spectroscopy (VUV) characterization of LbL films made with liposomes from 1.2-dipalmitoyl-sn-Glycero-3-[Phospho-rac-(1-glycerol)] (Sodium Salt) (DPPG) alternated with poly(allylamine hydrochloride) (PAH). Measurements in the 6.0-9.5eV range allowed us to identify the electronic transitions responsible for the spectra, which were assigned to carboxyl, hydroxyl and phosphate groups in DPPG while the PAH spectra were governed by electronic transitions in the amino groups. The surface mass density of the LbL films could be determined, from which the formation of a DPPG bilayer was inferred. This rupture of the liposomes into bilayers was confirmed with atomic force microscopy measurements. In subsidiary experiments we ensured that the UV irradiation in vacuum had negligible damage in the DPPG liposomes during the course of the VUV measurements. In addition to demonstrating the usefulness of VUV spectroscopy, the results presented here may be exploited in biological applications of liposome-containing films.

Adsorption kinetics of DPPG liposome layers: a quantitative analysis of surface roughness.

Roughness of a positively charged poly(allylamine hydrochloride) (PAH) polyelectrolyte surface was shown to strongly influence the adsorption of 1.2-dipalmitoyl-sn-3-glycero-[phosphorrac-(1-glycerol)] (DPPG) liposomes on it. The adsorption kinetic curves of DPPG liposomes onto a low-roughness PAH layer reveal an adsorbed amount of 5 mg/m², pointing to liposome rupture, whereas a high-roughness surface leads to adsorbed amounts of 51 mg/m², signifying adsorption of intact liposomes. The adsorption kinetic parameters calculated from adsorption kinetic curves allow us to conclude that the adsorption process is due to electrostatic interactions and also depends on processes such as diffusion and reorganization of lipids on the surface. Analysis of the roughness kinetics enabled us to calculate a growth exponent of 0.19 ± 0.07 and a roughness exponent of around 0.84, revealing that DPPG liposomes adsorbed onto rough surfaces follow the Villain self-affine model. By relating self-affine surfaces with hydrophobicity, the liposome integrity was explained by the reduction in the number of water molecules on the PAH surface, contributing to counterion anchorage near PAH ionic groups, reducing the liposome/PAH layer electrostatic forces and, consequently, avoiding liposome rupture.

Exacerbation of signs and symptoms of allergic conjunctivitis by a controlled adverse environment challenge in subjects with a history of dry eye and ocular allergy.

BACKGROUND: The goal of this study was to assess the effect of a controlled adverse environment (CAE) challenge on subjects with both allergic conjunctivitis and dry eye. METHODS: Thirty-three subjects were screened and 17 completed this institutional review board-approved study. Subjects underwent baseline ocular assessments and conjunctival allergen challenge (CAC) on days 0 and 3. Those who met the ocular redness and itching criteria were randomized to receive either the controlled adverse environment (CAE) challenge (group A, n = 9) or no challenge (group B, n = 8) at day 6. Thirty minutes after CAE/no-CAE, subjects were challenged with allergen and their signs and symptoms graded. Exploratory confocal microscopy was carried out in a subset of subjects at hourly intervals for 5 hours post-CAC on days 3 and 6. RESULTS: Seven minutes post-CAC, subjects exposed to the CAE had significantly greater itching (difference between groups, 0.55 ± 0.25, P = 0.028), conjunctival redness (0.59 ± 0.19, P = 0.002), episcleral redness (0.56 ± 0.19, P = 0.003) and mean overall redness (mean of conjunctival, episcleral, and ciliary redness, 0.59 ± 0.14, P < 0.001). The mean score at 7, 15, and 20 minutes post-CAC for conjunctival redness (0.43 ± 0.17, P = 0.012), episcleral redness (0.49 ± 0.15, P = 0.001), mean overall redness in all regions (0.43 ± 0.15, P = 0.005), and mean chemosis (0.20 ± 0.08, P = 0.017) were also all significantly greater in CAE-treated subjects. Confocal microscopic images of conjunctival vessels after CAC showed more inflammation in CAE-treated subjects. CONCLUSION: In subjects with both dry eye and allergic conjunctivitis, exposure to adverse environmental conditions causes an ocular surface perturbation that can intensify allergic reactions.

Polymeric scaffolds for enhanced stability of melanin incorporated in liposomes.

The use of melanin in bioinspired applications is mostly limited by its poor stability in solid films. This problem has been addressed here by incorporating melanin into dipalmitoyl phosphatidyl glycerol (DPPG) liposomes, which were then immobilized onto a solid substrate as an LbL film. Results from steady-state and time-resolved fluorescence indicated an increased stability for melanin incorporated into DPPG liposomes. If not protected by liposomes, melanin looses completely its fluorescence properties in LbL films. The thickness of the liposome-melanin layer obtained from neutron reflectivity data was 4.1+/-0.2 nm, consistent with the value estimated for the phospholipid bilayer of the liposomes, an evidence of the collapse of most liposomes. On the other hand, the final roughness indicated that some of the liposomes had their structure preserved. In summary, liposomes were proven excellent for encapsulation, thus providing a suitable environment, closer to the physiological conditions without using organic solvents or high pHs.

Exothermic rate restrictions in long-range photoinduced charge separations in rigid media.

Glycerol/methanol (9:1) mixtures at 255 K behave as rigid media for photoinduced electron transfers that take place within a few hundred nanoseconds. This media also provides enough polarity and plasticity to accommodate charge separations with reaction free energies ranging from +3 to -34 kcal/mol. The distance dependence of the electron transfer rates from electronically excited aromatic hydrocarbons to nitriles in this medium is accurately described by an exponential decay constant of 1.65 per angstrom. These photoinduced electron transfers display, for the first time in charge separations between independent electron donors and acceptors, a free-energy relationship with a maximum rate followed by a decrease in the rate for more exothermic reactions. According to this free-energy relationship, Franck-Condon factors are maximized at DeltaG(0) approximately -15 kcal/mol. It is suggested that the inverted region observed for these first-order photoinduced charge separations originates from a slower increase of their reorganization energies with DeltaG(0) than that of the analogous second-order photoinduced charge separations, for which inverted regions have never been clearly observed.

A highly reproducible continuous process for hydroxyapatite nanoparticles synthesis.

This work presents a continuous process for producing hydroxyapatite nanoparticles (NanoXIM) in a network reactor, NETmix, fed by a calcium solution, a phosphorus solution and an alkaline solution. Hydroxyapatite is considered a biomaterial, used as: food additives and nutritional supplements; bone graft for bone replacement, growth and repair; biocements and coating of metallic implant. Some of the most recent applications include their use in cosmetics, toothpaste and in esthetical treatments for diminishing wrinkles by stimulating conjunctive tissue formation. The proposed process enables the micromixing control, which is essential to form nanometric structures, but it is also a determining factor in the crystals purity, crystallinity and morphology. The reactants distribution scheme at the inlet of the reactor and along the reactor, performed continuously or varying in time, is also a crucial factor to programme the properties of reactant media along the reactor, such as the pH, the supersaturation degree, the Ca/P molar ratio, and the temperature. The calcium phosphate nanoparticles suspension that exits the reactor is submitted to further aging, separation, drying, sintering and milling processes.

Influence of ionic interactions on the photoinduced birefringence of poly[1-[4-(3-carboxy-4 hydroxyphenylazo) benzene sulfonamido]-1,2-ethanediyl, sodium salt] films.

Electrostatic interactions govern most properties of polyelectrolyte films, as in the photoinduced birefringence of azo-containing polymers. In this paper we report a systematic investigation of optical storage characteristics of cast and layer-by-layer (LbL) films of poly[1 -[4-(3-carboxy-4 hydroxyphenylazo) benzene sulfonamido]-1,2-ethanediyl, sodium salt] (PAZO). Birefringence was photoinduced faster in PAZO cast films prepared at high pHs, with the characteristic writing times decreasing almost linearly with the pH in the range between 4 and 9. This was attributed to an increased free volume for the azochromophores with the enhanced electrostatic repulsion in PAZO charged to a greater extent. In contrast, in LbL films of PAZO alternated with poly(allylamine hydrochloride) (PAH), the electrostatic interactions between the oppositely charged polymers hampered photoisomerization and molecular rearrangement, thus leading to a slower writing kinetics for highly charged

Temperature dependence of ultra-exothermic charge recombinations.

We measured the temperature dependence (from +32 to -50 degrees C) of charge-recombination rates between contact radical ion pairs in isopropyl ether. In the systems selected for this study, aromatic hydrocarbon cations are the electron acceptors and the fumaronitrile anion is the electron donor. Nearly quantitative electron transfers occur at all temperatures. The charge recombinations have excess exothermicities of -60 kcal mol(-1) and exhibit a very weak temperature dependence. Our observations emphasize the absence of solvent effects and the relevance of nuclear tunneling in charge recombinations.

Electron transfer in supercritical carbon dioxide: ultraexothermic charge recombination at the end of the "inverted region".

Charge-recombination rates in contact radical-ion pairs, formed between aromatic hydrocarbons and nitriles in supercritical CO(2) and heptane, decrease with the exothermicity of the reactions until they reach -70 kcal mol(-1), but from there on an increase is observed. The first decrease in rate is typical of the "inverted region" of electron-transfer reactions. The change to an increase in the rate for ultra-exothermic electron transfer indicates a new free-energy relationship. We show that the resulting "double-inverted region" is not due to a change in mechanism. It is an intrinsic property of electron-transfer reactions, and it is due to the increase of the reorganisation energy with the reaction exothermicity.

Effects of adjuvant therapy with 0.1% olopatadine hydrochloride ophthalmic solution on quality of life in patients with allergic rhinitis using systemic or nasal therapy.

BACKGROUND: Allergic rhinoconjunctivitis patients are often treated with nasal or systemic allergy therapy, forgoing therapy for ocular symptoms. This treatment regimen leaves important aspects of the allergic reaction untreated and affects quality of life (QoL). The Rhinoconjunctivitis Quality of Life Questionnaire and the Allergic Conjunctivitis Quality of Life Questionnaire quantify separate aspects of QoL. OBJECTIVE: To determine the benefit gained in QoL, measured by these questionnaires, when antiallergy eyedrops (olopatadine) were added to patients' preexisting regimens of nasal or systemic allergic rhinitis treatment. METHODS: This was a 4-week prospective, multicenter, open-label, crossover, environmental QoL study. Visit 1 randomized patients to treatment group A or B and included baseline examinations and questionnaires. Group A instilled olopatadine twice daily and concomitantly with previously prescribed nasal or systemic antiallergy medication for 2 weeks. Group B received no ocular therapy and used only previously prescribed antiallergy medication for 2 weeks. Treatment group crossover occurred at visit 2. Patients again completed the questionnaires at visits 2 and 3. RESULTS: Two hundred patients completed the study, 97 in group A and 103 in group B. Groups A and B experienced ocular allergic symptoms for 3.88 and 3.96 days, respectively, during the week before baseline. At visits 2 and 3, questionnaire scores were significantly improved for each group when olopatadine was added compared with the nontreatment periods. By visit 2, olopatadine improved QoL by 49% compared with 5% in the nontreated group (P < .001). CONCLUSIONS: In this study, 90.5% of patients with allergic rhinitis treated nasally or systemically also had ocular allergic symptoms. Adding olopatadine to these patients' medication regimens significantly improved ocular allergic symptoms and overall QoL.

Methodologies for the study of ocular surface disease.

The ability to obtain reliable results from clinical trials of therapies for ocular allergic disease and dry eye disease is often limited because of inadequate control of variables, such as environment, patient life style, compliance, and individual fluctuations that occur from one assessment visit to another. The controlled allergen challenge (CAC) model of allergic conjunctivitis allows signs and symptoms of the disease to be elicited in a physiologically accurate and reproducible manner. The rigid criteria for subject selection, the controlled allergic reaction, and the standardized and quantified grading systems allow for a reproducible baseline from which statistically and clinically significant differences between formulations can be assessed. Similarly, the controlled adverse environment (CAE) model for dry eye mimics the environmental stimuli that lead to ocular surface drying. Preselected subjects have a reproducible, homogeneous baseline reaction from which the effects of various treatments can be significantly evaluated and compared. CAC and CAE provide accurate means to study highly variable and individual ocular surface disease.