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PURPOSE: Symptom management among patients diagnosed with advanced cancer is a high priority in clinical care that often involves the support of a family caregiver. However, limited studies have examined parallel patient and caregiver symptom burden and associations with their own and each other's quality of life (QOL). This study seeks to identify patient and caregiver symptom clusters and investigate associations between identified clusters and demographic, clinical, and psychosocial factors (cognitive appraisals and QOL). METHODS: This study was a secondary analysis of self-reported baseline survey data collected from a randomized clinical trial of 484 adult advanced cancer patients and their caregivers. Latent class analysis and factor analysis were used to identify symptom clusters. Bivariate statistics tested associations between symptom clusters and demographic, clinical, and psychosocial variables. RESULTS: The most prevalent symptom for patients was energy loss/fatigue and for caregivers, mental distress. Low, moderate, and high symptom burden subgroups were identified at the patient, caregiver, and dyad level. Age, gender, race, income, chronic conditions, cancer type, and treatment type were associated with symptom burden subgroups. Higher symptom burden was associated with more negative appraisals of the cancer and caregiving experience, and poorer QOL (physical, social, emotional, functional, and overall QOL). Dyads whose caregivers had more chronic conditions were more likely to be in the high symptom burden subgroup. CONCLUSION: Patient and caregiver symptom burden influence their own and each other's QOL. These findings reinforce the need to approach symptom management from a dyadic perspective.
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Objective: This study explores the intricate relationship between social support and eating behaviors in children and adolescents, considering the mediating role of eating self-efficacy and the moderating effects of body mass index (BMI) and weight concern. Methods: Data from 1986 primary and secondary school students aged 8 to 17 in Shanghai, China, were analyzed using moderated mediation analysis. Results: The results demonstrate a robust positive association between social support and eating self-efficacy, particularly prominent among individuals with low BMI (effect = 0.506, 95% CI [0.376, 0.636]). Moreover, the study highlights that eating behavior is influenced not only by eating self-control (ß = -0.054, 95% CI [-0.062, -0.046]) but also by the interaction term between individuals' perceptions of their body weight (ß = -0.0008, 95% CI [-0.0015, -0.0001]). Conclusion: Eating self-efficacy serves as a mediator in the relationship between social support and eating behavior, modulated by BMI and weight concern. Importantly, high weight concern significantly strengthens the mediating effect of eating self-efficacy on the relationship between social support and eating behavior, regardless of BMI.
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Alzheimer's Disease (AD) is a complex neurodegenerative disorder significantly influenced by sex differences, with approximately two-thirds of AD patients being women. Characterizing the sex-specific AD progression and identifying its progression trajectory is a crucial step to developing effective risk stratification and prevention strategies. In this study, we developed an autoencoder to uncover sex-specific sub-phenotypes in AD progression leveraging longitudinal electronic health record (EHR) data from OneFlorida+ Clinical Research Consortium. Specifically, we first constructed temporal patient representation using longitudinal EHRs from a sex-stratified AD cohort. We used a long short-term memory (LSTM)-based autoencoder to extract and generate latent representation embeddings from sequential clinical records of patients. We then applied hierarchical agglomerative clustering to the learned representations, grouping patients based on their progression sub-phenotypes. The experimental results show we successfully identified five primary sex-based AD sub-phenotypes with corresponding progression pathways with high confidence. These sex-specific sub-phenotypes not only illustrated distinct AD progression patterns but also revealed differences in clinical characteristics and comorbidities between females and males in AD development. These findings could provide valuable insights for advancing personalized AD intervention and treatment strategies.
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A novel approach for the simultaneous separation of zearalenone (ZEN) and four types of aflatoxins (AFB1, AFB2, AFG1 and AFG2) from rice samples was presented. This approach utilized modified MIL-101(Cr)-NH2 as core, with molecularly imprinted polymers (MIPs) serving as the shell. The MIL-101(Cr)-NH2 was prepared via ring-opening reaction, while the imprinted polymers were synthesized using warfarin and 4-methylumbelliferyl acetate as co-pseudo template, ethylene glycol dimethacrylate as the cross-linker and azobisisobutyronitrile as initiator. The resulting co-pseudo-template-MIPs (CPT-MIPs) were thoroughly characterized and evaluated. Adsorption studies demonstrate that the adsorption process of CPT-MIPs follows a chemical monolayer adsorption mechanism, with imprinted factors ranging from 1.24 to 1.52 and selective factors ranging from 1.29 to 1.52. Self-made columns were prepared, and the method for separation was developed and validated. The limit of detections ranged from 0.12 to 2.09 µg/kg, and the limit of qualifications ranged from 1.2 to 6.25 µg/kg. To assess the reliability of the method, ZEN and AFs were spiked at three different levels, and the recoveries ranged from 79.53 to 94.58%, with relative standard deviations of 2.90-5.78%.
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In the extraction of fetal electrocardiogram (ECG) signal, due to the unicity of the scale of the U-Net same-level convolution encoder, the size and shape difference of the ECG characteristic wave between mother and fetus are ignored, and the time information of ECG signals is not used in the threshold learning process of the encoder's residual shrinkage module. In this paper, a method of extracting fetal ECG signal based on multi-scale residual shrinkage U-Net model is proposed. First, the Inception and time domain attention were introduced into the residual shrinkage module to enhance the multi-scale feature extraction ability of the same level convolution encoder and the utilization of the time domain information of fetal ECG signal. In order to maintain more local details of ECG waveform, the maximum pooling in U-Net was replaced by Softpool. Finally, the decoder composed of the residual module and up-sampling gradually generated fetal ECG signals. In this paper, clinical ECG signals were used for experiments. The final results showed that compared with other fetal ECG extraction algorithms, the method proposed in this paper could extract clearer fetal ECG signals. The sensitivity, positive predictive value, and F1 scores in the 2013 competition data set reached 93.33%, 99.36%, and 96.09%, respectively, indicating that this method can effectively extract fetal ECG signals and has certain application values for perinatal fetal health monitoring.
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Algoritmos , Electrocardiografía , Procesamiento de Señales Asistido por Computador , Humanos , Electrocardiografía/métodos , Embarazo , Femenino , Monitoreo Fetal/métodos , Feto/fisiologíaRESUMEN
PURPOSE: To examine the associations of role (localized prostate cancer (PCa) patient vs. their intimate partner), area deprivation index (ADI-higher scores indicating higher neighborhood deprivation levels), and race (Black/African American (AA) vs. White) with health behaviors and body mass index (BMI) among PCa patients and partners. The behaviors include smoking, alcohol consumption, diet quality, sedentary behaviors, and physical activity (PA). METHODS: This study used the baseline data collected in a clinical trial. Given the nested structure of the dyadic data, multi-level models were used. RESULTS: Significant role-race interaction effects on smoking, ADI-race effects on alcohol consumption, and role-ADI effects on BMI were found. Meanwhile, patients smoked more cigarettes, decreased alcohol consumption, had less healthful diets, spent longer time watching TV, did fewer sedentary hobbies, had more confidence in PA, and had higher BMIs than their partners. High ADI was independently associated with lower odds of drinking alcohol, using computer/Internet, and doing non-walking PA, and higher BMI compared to low ADI controlling for role and race. Black/AA dyads had less smoking amount and alcohol consumption and higher sedentary time and BMI than White dyads when adjusted for role and ADI. CONCLUSIONS: This study identified significant interaction and main effects of role, ADI, or race on health behaviors and BMI. IMPLICATIONS FOR CANCER SURVIVORS: Future behavioral interventions should address divergent individual needs between patients and partners, social and neighborhood barriers, and cultural indicators of racial groups to promote healthful behaviors and improve the quality of survivorship for PCa patients and partners.
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Objectives: Tai Chi (TC) shows some beneficial effects in reducing pain in knee osteoarthritis (OA). However, the selection of criteria TC forms in previous studies were unclear and inconsistent, possibly accounting for the varying outcomes and rendering the training effects suboptimal. We have selected four optimal TC (OTC) forms based on the knee joint load and its association with pain. This pilot study sought to examine the effect of the OTC forms on reducing knee pain in individuals with knee OA. Methods: Fifteen knee OA participants were recruited. Their knee joint pain level was rated by using the Visual Analogue Scale before and after two weeks of OTC training and compared between these two assessments. Results: The two-week OTC training course was well accepted by our participants. The knee OA pain showed a significant reduction (median pain score: 5 âcm before training and 1 âcm post-training, Wilcoxon p â< â0.001) after the two-week training program. Conclusions: Our pilot results revealed that the 2-week four-form-based OTC program could significantly reduce the knee pain level in people with knee OA. Additionally, our OTC program appears to be about 50% more effective in reducing knee pain than the existing TC-based program, which uses 10 âTC forms over 12 weeks (1.59 vs. 1.06 in Hedge's g). The findings in this study may inform the development of OTC-based knee pain reduction programs and the design of relevant clinical trials to establish OTC's effectiveness, safety, and dose-response relationship in easing knee OA pain.
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PURPOSE: Smoking is a modifiable lifestyle factor that has not been established as a prostate cancer risk factor, nor emphasized in prostate cancer prevention. Studies have shown that African American (AA) smokers have a poorer cancer prognosis than European Americans (EAs), while having a lower prevalence of heavy smoking. We examined the relationship between cigarette smoking and prostate cancer aggressiveness and assessed racial differences in smoking habits on the probability of high-aggressive prostate cancer. METHODS: Using data from the North Carolina-Louisiana Prostate Cancer Project (n = 1,279), prostate cancer aggressiveness was defined as high or low based on Gleason scores, serum prostate-specific antigen levels, and tumor stage. Cigarette smoking was categorized as current, former, or never smokers. Multivariable logistic regression was used to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI). RESULTS: Self-reported current (OR = 1.99; 95% CI 1.30-3.06) smoking was associated with high-aggressive prostate cancer relative to never smokers. When stratified by self-reported race, the odds of having high-aggressive cancer increased among AA current (OR = 3.58; 95% CI 2.04-6.28) and former smokers (OR = 2.21; 95% CI 1.38-3.53) compared to AA never smokers, but the odds were diminished among the EA stratum (Pself-reported race x smoking status = 0.003). CONCLUSION: Cigarette smoking is associated with prostate cancer aggressiveness, a relationship modulated by self-reported race. Future research is needed to investigate types of cigarettes smoked and metabolic differences that may be contributing to the racial disparities observed.
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This work involves the introduction of niobium oxide into lanthanum aluminate (LaAlO3) via a conventional solid-state reaction technique to yield LaAlO3:Nb (LaNbxAl1-xO3+δ) samples with Nb5+ doping levels ranging from 0.00 to 0.25 mol%. This study presents a comprehensive investigation of the effects of niobium doping on the phase evolution, defect control, and reflectance of LaNbxAl1-xO3+δ powder. Powder X-ray diffraction (XRD) analysis confirms the perovskite structure in all powders, and XRD and transmission electron microscopy (TEM) reveal successful doping of Nb5+ into LaNbxAl1-xO3+δ. The surface morphology was analyzed by scanning electron microscopy (SEM), and the results show that increasing the doping concentration of niobium leads to fewer microstructural defects. Oxygen vacancy defects in different compositions are analyzed at 300 K, and as the doping level increases, a clear trend of defect reduction is observed. Notably, LaNbxAl1-xO3+δ with 0.15 mol% Nb5+ exhibits excellent reflectance properties, with a maximum infrared reflectance of 99.7%. This study shows that LaNbxAl1-xO3+δ powder materials have wide application potential in the field of high reflectivity coating materials due to their extremely low microstructural defects and oxygen vacancy defects.
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BACKGROUND: Managing medications for Alzheimer's disease and related dementias is challenging for caregivers. Information about caregivers' strategies to manage these challenges is needed to inform intervention development. OBJECTIVE: This study aimed to understand caregivers' medication management experiences by analyzing online community discussions. METHODS: Posts were extracted from the ALZConnected® Forum using keywords "medication" and "drug" via web scraping. The researchers applied thematic analysis. RESULTS: Four major themes emerged: (1) role transition of medication management responsibilities, (2) caregivers' uncertainty about medication purpose and values, (3) conflicts between the care recipients and caregivers, and (4) difficulty accessing and affording medications. CONCLUSIONS: The experiences shared on a non-moderated, unstructured online forum indicate that medication management is challenging and overwhelming for caregivers of people living with Alzheimer's disease and related dementias. Since this is a progressive disease with various stages and changing needs, caregivers' strategies vary and are often limited by available resources and support. Health care providers should offer training and support for caregivers to navigate the transfer of medication management responsibilities and changing care needs as the disease progresses.
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Enfermedad de Alzheimer , Humanos , Enfermedad de Alzheimer/tratamiento farmacológico , Administración del Tratamiento Farmacológico , CuidadoresRESUMEN
The pre-oxidation process of Polyacrylonitrile (PAN) fibers is a complex procedure involving multiple stages of temperature increase and isothermal temperature retention. However, the impact of the temperature increase stage on PAN fiber has often been overlooked. To address this, samples were collected before and after the temperature increase and isothermal retention stages, treating them as separate influencing factors. Therefore, the pre-oxidation process can be divided into four distinct stages: (1) A temperature increase stage before the cyclization reactions: the PAN fiber's small-size crystals melt, and the crystal orientation changes under fixed tension, leading to shrinkage and increased orientation of the micropore. (2) An isothermal retention stage before the cyclization reactions: The crystal structure maintains well, resulting in minimal micropore evolution. The PAN fiber's crystal orientation and micropore orientation increased under fixed tension. (3) A temperature increase stage after the cyclization reactions: The PAN fiber's crystal melts again, reducing the average chord length and relative volume of the micropore. However, the PAN fiber can recrystallize under fixed tension. (4) An isothermal retention stage after the cyclization reactions: Significant crystal melting of the PAN fiber occurs, but the highly oriented crystals are maintained well. The average chord length and relative volume of the micropore increase. Recommendations for improving the pre-oxidation process are made according to these stages.
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BACKGROUND: Loneliness is a frequent experience among family members engaging in caregiving responsibilities and may vary across racial and ethnic groups. This study aimed to examine (a) the difference in loneliness between non-Hispanic Black and non-Hispanic White caregivers, (b) the associations between loneliness and perceptions of choice and purpose in caregiving, and (c) whether those associations with loneliness differ by caregivers' race. METHOD: Descriptive statistics and ordinal logistic regression were conducted in a population-based sample of 1000 caregivers (Black caregivers, n = 199; White caregivers, n = 801) from the 2020 Caregiving in the U.S. STUDY: The survey design was properly addressed. Key variables included loneliness (level of feeling alone about being a caregiver), choice (whether or not reporting a choice in taking on the caregiver responsibility), sense of purpose (level of purpose/meaning in life from caregiving), and race (Black/White). Models adjusted for caregiving characteristics (e.g., hour of caregiving) and sociodemographic characteristics (e.g., age and education). RESULTS: Black caregivers had lower odds of reporting a higher level vs. a lower level of loneliness than White caregivers (aOR = 0.67, 95%CI = 0.47, 0.96). Reporting having no choice was associated with higher odds of a higher level of loneliness (aOR, 0.77, 95%CI = 0.67, 0.88). Higher sense of purpose scores were associated with lower odds of a higher level of loneliness (aOR = 0.81, 95%CI = 0.71, 0.93). No significant moderation effects of race were found. CONCLUSION: Black caregivers reported lower loneliness scores than White caregivers. Reporting no choice and lower sense of purpose were associated with higher loneliness in both racial groups.
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Negro o Afroamericano , Cuidadores , Soledad , Población Blanca , Humanos , Soledad/psicología , Cuidadores/psicología , Cuidadores/estadística & datos numéricos , Masculino , Femenino , Población Blanca/psicología , Población Blanca/estadística & datos numéricos , Persona de Mediana Edad , Negro o Afroamericano/psicología , Negro o Afroamericano/estadística & datos numéricos , Anciano , Adulto , Estados Unidos , Conducta de Elección , Encuestas y Cuestionarios , Familia/psicologíaRESUMEN
PURPOSE: To examine the association of marital status with prostate cancer outcomes in a racially-diverse cohort. METHODS: The study population consisted of men (1010 Black; 1070 White) with incident prostate cancer from the baseline North Carolina-Louisiana Prostate Cancer (PCaP) cohort. Marital status at time of diagnosis and screening history were determined by self-report. The binary measure of marital status was defined as married (including living as married) vs. not married (never married, divorced/separated, or widowed). High-aggressive tumors were defined using a composite measure of PSA, Gleason Score, and stage. Definitive treatment was defined as receipt of radical prostatectomy or radiation. Multivariable logistic regression was used to examine the association of marital status with (1) high-aggressive tumors, (2) receipt of definitive treatment, and (3) screening history among Black and White men with prostate cancer. RESULTS: Black men were less likely to be married than White men (68.1% vs. 83.6%). Not being married (vs. married) was associated with increased odds of high-aggressive tumors in the overall study population (adjusted Odds Ratio (aOR): 1.56; 95% Confidence Interval (CI): 1.20-2.02) and both Black and White men in race-stratified analyses. Unmarried men were less likely to receive definitive treatment in the overall study population (aOR: 0.68; 95% CI: 0.54-0.85). In race-stratified analyses, unmarried Black men were less likely to receive definitive treatment. Both unmarried Black and White men were less likely to have a history of prostate cancer screening than married men. CONCLUSION: Lower rates of marriage among Black men might signal decreased support for treatment decision-making, symptom management, and caregiver support which could potentially contribute to prostate cancer disparities.
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Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/patología , Detección Precoz del Cáncer , Antígeno Prostático Específico , Blanco , Estado CivilRESUMEN
Using a solvent-free radical grafting technique, glycidyl methacrylate (GMA) and maleic anhydride (MAH) were used as functionalized graft monomers, styrene (St) as a copolymer monomer, and grafted onto polylactic acid (PLA). A series of PLA-g-(GMA/MAH-co-St) graft copolymers were prepared by adjusting the GMA/MAH ratio. Subsequently, the prepared graft copolymers were used as a compatibilizer with PLA and polypropylene carbonate (PPC) for melt blending to prepare PLA/PPC/PLA-g-(GMA/MAH-co-St) blends. The effects of changes in the GMA/MAH ratio in the graft copolymer on the thermodynamics, rheology, optics, degradation performance, mechanical properties, and microstructure of the blend were studied. The results found that GMA, MAH, and St were successfully grafted onto PLA, and the PLA-g-(GMA/MAH-co-St) graft copolymer obtained from the reaction had a good toughening effect on the PLA/PPC blend system, which significantly improved the mechanical properties of the PLA/PPC/PLA-g-(GMA/MAH-co-St) blend without reducing its degradation performance, resulting in a biodegradable blend material with excellent comprehensive performance. In the PLA-g-(GMA/MAH-co-St) grafting reaction system, when GMA/MAH = 1.5/1.5 (w/w), the grafting degree of the graft copolymer increased most significantly, from 0.83 phr to 1.51 phr. This composition of graft copolymer can effectively improve the compatibility between PLA and PPC. The resulting PLA/PPC blend can maintain good melt flow properties (MFR of 14.51 g/10 min), high transparency, and low haze (light transmittance of 91.56 %, haze of 20.5 %), while significantly improving its thermal stability (T95%, Tmax, and Et increased by 12.87 °C, 20.33 °C, and 32.00 kJ/mol, respectively). Moreover, when introducing PLA-g-(GMA/MAH-co-St) (GMA/MAH = 1.5/1.5 (wt/wt)) graft copolymer into the system, the toughness of the PLA/PPC/PLA-g-(GMA/MAH-co-St) blend system is optimal, with the notch impact strength and fracture elongation increasing to 184.6 % and 535.4 % of the PLA/PPC blend, respectively, at which point the fracture surface of the impact sample shows a wrinkled fracture feature indicative of toughness.
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Compuestos Epoxi , Metacrilatos , Poliésteres , Polímeros , Poliésteres/química , Polímeros/química , Polipropilenos , Anhídridos Maleicos , EstirenoRESUMEN
Cardanol (CD) is used as a reactive compatibilizer, and blended with polylactic acid (PLA) and polypropylene carbonate (PPC) resin (70/30(w/w)) to obtain a series of PLA/PPC/CD blends. The systematic study was conducted on the thermal properties, optical properties, rheological properties, mechanical properties, and microscopic morphology of the blend, by varying amounts of CD added to the blends. A detailed explanation and comprehensive analysis of the reaction mechanism between CD and PLA/PPC have been made. The study found that CD acts as a "bridge" between the PLA and PPC, forming the structure of a block copolymer (PLA-b-CD-b-PPC), and the copolymer can greatly improve the compatibility of PLA and PPC. When the amount of CD reaches 8 wt%, only one Tg is observed in the blend, simultaneously, PLA/PPC has already transitioned from a partially compatible system to a completely compatible system. At the same time, the addition of CD does not have any negative impact on the thermal stability of the PLA/PPC blend under processing temperature conditions, and the thermal stability of the PLA/PPC/CD blends can even be improved under extreme conditions. In addition, the addition of CD allows the PLA/PPC/CD blends to maintain a high light transmittance while reducing the opacity of the blend (the light transmittance remains above 92 %, and the opacity is reduced from 37 % to about 24 %), demonstrating excellent optical properties. Moreover, the elongation at break and impact strength of the PLA/PPC/CD blend both show a trend of first increasing and then decreasing with the increase of CD amount. When the CD amount varies within the range of 6- 8 wt%, the blends undergoes a brittle-ductile transition, and its toughness is greatly improved while the rigidity can also meet practical needs. When the amount of CD in the system increases to 12 wt%, the toughness of the blend reaches its peak, and its elongation at break and impact strength reach 513.24 % and 9211.5 J/m2 respectively (increased to 2442.84 % and 270.73 % of the PLA/PPC blend). Concurrently, the fracture surface of the blend exhibits large-scale plastic flow in the direction of the applied force, with marked shear yield phenomena, showing obvious characteristics of tough fracture.
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Fenoles , Poliésteres , Polipropilenos , Microscopía Electrónica de Rastreo , Poliésteres/químicaRESUMEN
Polyethylene (PE)-based elastomers are the ideal choice for enhancing the compatibility of polypropylene/polyethylene (PP/PE) blends and improving the mechanical properties of PP-based materials. However, the issue of blend systems lies in the interplay between the crystallization processes. Therefore, we investigated the crystallization behavior during the cooling process of a new generation of PP/PE block copolymers (PP-b-PE) and random polypropylene (PPR, a copolymer of propylene and a small amount of ethylene or an alpha-olefin) blends using in-situ X-ray diffraction/scattering and differential scanning calorimetry (DSC) techniques. We also conducted mechanical performance tests on PPR/PP-b-PE blends at room temperature and low temperature (-5 °C). The results indicate that during the cooling process, the PP phase of PP-b-PE will follow the PPR to crystallize in advance and form a eutectic mixture, thereby enhancing the compatibility of PP/PE. Moreover, the PPR/PP-b-PE blend will form stable ß-(300) crystals with excellent mechanical properties. Due to the improved compatibility of PP/PE with PP-b-PE, PE crystals are dispersed within PP crystals, providing bonding that improves the toughness of PPR under the low stiffness failure conditions of PPR/PP-b-PE blends, thereby enhancing their impact performance at low and room temperatures. This research has great significance for both recycling waste plastics and enhancing the low-temperature toughness of PPR.
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Tin oxide (SnO2) is widely used as an inorganic electron transport layer (ETL) for rigid and flexible perovskite solar cells (PSCs). In this work, an extract of snail shell, the sodium salt of polyaspartic acid (S-PASP), a water-soluble polypeptide polymer, has been used to multifunctionally regulate SnO2 nanograins. S-PASP has a strong chelating and dispersing effect; thus, chemically adsorbed SnO2 can inhibit agglomeration. The S-PASP:SnO2 ETL also improved the extraction and transferability of carriers, reducing body defects and interfacial charge. Moreover, the S-PASP:SnO2 ETL promotes the vertical growth of the perovskite crystals due to its bottom-up morphology, wettability, and strain release, which is conducive to improving the photoelectric performance of the device. The optimized rigid device prepared under open-air conditions obtained a PCE of 20.92%. In addition, due to the stress compensation of the S-PASP long chain, which prevented the cracking and displacement of the ETL, the optimal PCE of the flexible device was 17.96%, and the initial efficiency was maintained at 82.8% after 100 bends. This work introduces a molecular doping mechanism for organic-inorganic hybrid electronics.
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In recent years, air-processed MAPbI3 perovskite solar cells (PSCs) have attracted widespread interest from researchers worldwide because of their simple and low-cost fabrication process. Nonetheless, the ambient conditions usually bring about many adverse effects, such as imperfect crystallization and numerous defects in perovskite films, which seriously impact both the photoelectric performance and stability of the device. Therefore, in this work, a polymer dual-passivation strategy was employed by introducing ammonium polyphosphate (APP) as an additive to the green anti-solvent to accurately modify the perovskite layer. APP, which has abundant phosphate and ammonium groups, could simultaneously fill the I/Pb vacancies by Lewis acid-base reactions to restrain defect formation and improve the power conversion efficiency (PCE) of the ultimate device. On the other hand, the long molecular chains of the polymer with a certain flexural ability were easily congregated at the grain boundaries of the perovskite grains, thus enhancing the bending resistance. Consequently, high-quality perovskite films with a dense morphology and large grain size were obtained. Because of the reduced defect density and suppressed non-radiative recombination, the optimal PSC attained a champion PCE of 20.87% with negligible hysteresis. Furthermore, the non-encapsulated APP-modified flexible device also exhibited excellent bending resistance. Only 20% of its normalized PCE was lost after 150 bending cycles at room temperature. This simple, green, low-cost, and reliable strategy for preparing high-efficiency PSCs with good stability can facilitate its commercialization.
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Epoxidized soybean oil (ESO) was used as a compatibilizer and blended with polylactic acid (PLA) and polypropylene carbonate (PPC) resin to prepare a series of PLA/PPC/ESO blends with varying compositions. The influence of the variation in the amount of ESO added to the blend system on the thermal properties, optical properties, rheological properties, mechanical properties, and microscopic morphology of the blends was studied. The research indicates that ESO can react with PLA and PPC to form a chemical bond interface, which improves the compatibility of PLA and PPC to a certain extent. With the increase in the amount of ESO added to the blend (1- 5 phr), the complete decomposition temperature, storage modulus, loss modulus, complex viscosity, notched impact strength, and elongation at break of the blend all show a trend of continuous increase. At the same time, the melt flow rate, light transmittance, and tensile strength of the blend do not show significant fluctuations. When the amount of ESO in the system is 5 phr, compared with the PLA/PPC blend, the notched impact strength and elongation at break of the PLA/PPC/ESO blend increase from 4270.3 J/m2, 43.89 % to 8560.4 J/m2, 211.28 %, respectively, and its tensile strength and transmittance still remain around 63 MPa, 92 %. This improves the toughness of the blend while maintaining its rigidity, demonstrating excellent mechanical and optical properties. At this time, the microscopic morphology of the fracture surface of the impact sample also shows obvious characteristics of tough fracture. However, when the amount of ESO added to the blend is excessive (6 phr), the compatibility of the blending system decreases, which will degrade the performance of the blending material and ultimately destroy the phase morphology of the blend and reduce its mechanical properties.
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Poliésteres , Aceite de Soja , Poliésteres/química , Polipropilenos/químicaRESUMEN
OBJECTIVE: The relationship between illness uncertainty and quality of life (QOL) has been examined for either the patient or caregiver, but not among the patient-caregiver dyads. This study examined relationships between illness uncertainty and QOL among patients with advanced cancer and family caregivers. METHODS: We conducted a secondary analysis of data from a randomized clinical trial that examined the effects of a dyadic-based intervention on psychological outcomes for patients with advanced cancer and family caregivers (N = 484 dyads). Illness uncertainty and QOL were measured using the shorten version of the Mishel Uncertainty in Illness Scale for Adult and the Functional Assessment of Cancer Therapy, respectively. The actor-partner interdependence model was used to examine whether an individual's uncertainty (either a patient's or caregiver's) was associated with their own QOL (i.e., an actor effect) and/or their partner's QOL (i.e., a partner effect). RESULTS: Significant actor effects included a negative association between patients' uncertainty and their own QOL (b = -0.422; p < 0.001) and a negative association between caregivers' uncertainty and their own QOL (b = -0.408; p < 0.001). In terms of partner effects, patients' uncertainty was negatively associated with caregivers' QOL (b = -0.095; p < 0.01). No partner effect was found for caregivers, suggesting that caregivers' uncertainty was not related to patients' QOL. CONCLUSIONS: Study findings support targeted interventions offered to both patients and their family caregivers to manage their illness uncertainty and improve their QOL.