Relationships among mental health, social capital and life satisfaction in rural senior older adults: a structural equation model.

BACKGROUND: Literature about life satisfaction in rural senior older adults is scarce. The aim of this research was to examine the relationships among mental health, social capital and life satisfaction in rural senior older adults. METHODS: This was a cross-sectional study. From July to October 2017, 245 senior older adults from 14 villages of Jinhua City in China were recruited. The Satisfaction with Life Scale (SWLS), the Chinese Version of the 12-item General Health Questionnaire (GHQ-12), the Social Capital Questionnaire (SCQ) and a self-designed questionnaire was administered to the participants. Structural equation modelling was implemented to analyse the relationships between mental health, social capital and life satisfaction in rural senior older adults. RESULTS: The structural equation model was fitting adequately (χ2/df = 1.785, P < 0.001; RMSEA = 0.059; CFI = 0.963). Life satisfaction was positively affected by income (ß = 0.243, P = 0.01). Likewise, community canteen services improved life satisfaction (ß = 0.288, P = 0.001). Social capital had direct positive prediction on life satisfaction (ß = 0.342, P = 0.003) and indirectly improved life satisfaction through mental health (ß =0.183, P = 0.007). Life satisfaction was impaired by poor mental health among senior older adults (ß = - 0.395, P < 0.026). CONCLUSIONS: Life satisfaction among rural senior older adults is a multifaceted well-being construct affected by income, community canteen services, social capital and mental health. The presented model highlights the positive effect of income, community canteen services, social capital and mental health. Appropriate home-based aged care, programs and policies are needed.

Redox Conversion of Chromium(VI) and Arsenic(III) with the Intermediates of Chromium(V) and Arsenic(IV) via AuPd/CNTs Electrocatalysis in Acid Aqueous Solution.

Simultaneous reduction of Cr(VI) to Cr(III) and oxidation of As(III) to As(V) is a promising pretreatment process for the removal of chromium and arsenic from acid aqueous solution. In this work, the synergistic redox conversion of Cr(VI) and As(III) was efficiently achieved in a three-dimensional electrocatalytic reactor with synthesized AuPd/CNTs particles as electrocatalysts. The AuPd/CNTs facilitated the exposure of active Pd{111} facets and possessed an approximate two-electron-transfer pathway of oxygen reduction with the highly efficient formation of H2O2 as end product, resulting in the electrocatalytic reduction of 97.2 ± 2.4% of Cr(VI) and oxidation of 95.7 ± 4% of As(III). The electrocatalytic reduction of Cr(VI) was significantly accelerated prior to the electrocatalytic oxidation of As(III), and the effectiveness of Cr(VI)/As(III) conversion was favored at increased currents from 20 to 150 mA, decreased initial pH from 7 to 1 and concentrations of Cr(VI) and As(III) ranging from 50 to 1 mg/L. The crucial intermediates of Cr(V) and As(IV) and active free radicals HO(•) and O2(•-) were found for the first time, whose roles in the control of Cr(VI)/As(III) redox conversion were proposed. Finally, the potential applicability of AuPd/CNTs was revealed by their stability in electrocatalytic conversion over 10 cycles.

Electronegativity-dependent Pt anchoring and molecule adsorption for graphene-based supported Pt single atom.

CONTEXT: To unravel the effects of the C vacancy, doping N type and number, the adsorption of HCHO and O2 was investigated on the graphene (Gr)-based supported Pt single atom by density functional theory calculations. The electronegativity of the vacancy and N-doped Gr was a crucial factor both for the anchoring for a Pt and the further adsorption of HCHO and O2 on the supported Pt. The electronegativity can be tuned by the C vacancy number (1V and 2V), the doping N type (graphitic-N, pyridinic-N and pyrrolic-N) and the doping pyridinic-N number (1N ~ 4N). The high electronegativity of the vacancy and N-doped Gr favored the anchoring for a Pt compared to the Gr, while too high electronegativity was detrimental for further adsorption of adsorbates on the supported Pt. The Bader charge analysis proved that the electronegativity followed the trend as pyrrolic-N > pyridinic-N > graphitic-N, and 4N-Gr > 2V-Gr > 3N-Gr > 2N-Gr > 1N-Gr > 1V-Gr > Gr. As a result, the pyridinic-N, the 1V-Gr, 1N-Gr and 2N-Gr with the suitable electronegativity achieved both stronger anchoring for a Pt and more favorable adsorption of HCHO and O2 on the supported Pt than the pristine Gr support. METHODS: Periodic DFT calculation was performed using the VASP code. The PAW method and the GGA-PBE functionals were used. Part of work was also carried out by the DSPAW procedure of Device Studio.

Effect of a mutual goal-based continuous care program on self-management behaviour and health outcomes in patients after percutaneous coronary intervention: A randomized controlled trial.

AIMS: To evaluate the effects of mutual goal-based continuous care program on the outcomes of patients with coronary heart disease (CHD) after percutaneous coronary intervention (PCI). DESIGN: A single-blinded randomized controlled trial. METHODS: 87 patients with CHD after PCI in Hangzhou, Zhejiang, China, were randomly divided into study (n = 42) and control (n = 45) groups. The control group received 12-week cardiac rehabilitation and routine care. The study group received routine care and cardiac rehabilitation and the 12-week intervention program developed according to the goal attainment theory, including the mutual goal-based face-to-face guidance, and every-2-week telephone follow-ups. The self-management behaviour, quality of life, unscheduled readmission rate, and satisfaction of patients were examined. RESULTS: For the patients subjected to the developed continuous nursing program based on mutual goals, achievement rates of all dimension mutual goals were at high levels (from 80.21% to 98.41%), except for the weight control (60.94%). Moreover, according to the comparable base data, compared with the control group, the self-management behaviour (study group 93.43 vs. control group 76.00), quality of life (QoL), and patients' satisfaction (study group 4.64 vs. control group 4.11) were higher, while the unscheduled readmission rate (study group 4.76% vs. control group 22.22%) was lower, in the study group, with statistically significant differences.

Development of the health literacy assessment instrument for chronic pain patients: A Delphi study.

AIM: To develop health literacy assessment instrument for patients with chronic pain. DESIGN: Qualitative methods based on Delphi technique, assessed against the CREDES checklist. METHODS: A 2-round Delphi method was adopted in this study. The panel consisted of 19 experts. RESULTS: The health literacy assessment instrument for chronic pain patients was constructed, which contained 3 dimensions (functional health literacy, interactive health literacy and critical health literacy) and 41 items. The positive coefficients of two rounds Delphi were 100.00% and 89.5%, respectively. The authority coefficient of experts was 0.848 and 0.858, respectively. The coordination coefficients of dimension and items were 0.222 and 0.364, respectively. CONCLUSIONS: The health literacy assessment instrument dimensions and items for patients with chronic pain based on a Delphi method are valid. This instrument is suitable for investigating the health literacy level of patients with chronic pain.

Nitric oxide releasing alginate microspheres for antimicrobial application.

The controlled release of nitric oxide (NO) is significantly crucial in the NO-related biomedical field. In the current work, the controlled release of NO from alginate microspheres was achieved through the direct impregnation of S-nitroso-N-acetyl-penicillamine (SNAP) in the gelation of sodium alginate with calcium ions. The loading rate of SNAP in alginate microspheres was obtained in a range of 0.69 %­27.5 %. Specifically, the longest NO release time reached up to ∼93 h. Furthermore, the structure, thermal properties, and morphology were fully characterized. During the antibacterial studies, the NO-releasing spheres can produce a great bactericidal effect on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The alginate microspheres impregnated with 315 mg SNAP (sphere size: 2.88 mm) can effectively reduce the number of bacteria by 7 orders of magnitude with an inhibition rate up to 100 %. Therefore, we anticipated that these NO-releasing alginate microspheres would have great potential for biomedical-related applications.

Mediating Role of Psychological Capital in the Relationship Between Social Support and Self-Neglect Among Chinese Community-Dwelling Older Adults.

Objectives: Self-neglect in older adults has become an important public health issue and is associated with negative health outcomes and increased morbidity and mortality. Social support has been recognized as a prominent predictor of self-neglect, but the underlying mechanism is unclear. This study aims to investigate and illustrate the associations among social support, psychological capital, and self-neglect. Methods: This study used a cross-sectional convenience sampling design. A total of 511 older adults were recruited in Chinese communities. Spearman's correlation coefficient and hierarchical multiple regression analysis were performed to assess the influencing factors of self-neglect. A structural equation model was applied to test the hypothesized mediation model. Results: Social support and psychological capital were found to be negatively related to self-neglect. Social support and psychological capital explained 5.1 and 11.9% of the incremental variances of older adults' self-neglect, respectively. Psychological capital acts as a mediator between social support and self-neglect. Conclusion: Self-neglect among older adults is a rising problem in China. Social support and higher psychological capital could decrease the risk of self-neglect in older adults. It is crucial to improve social networks and facilitate psychological interventions to reduce such self-neglect.

Medical and non-medical students' knowledge, attitude and willingness towards the COVID-19 vaccine in China: a cross-sectional online survey.

In the context of the novel Coronavirus outbreak and China's official policy of free vaccination against COVID-19 for all, medical students' attitudes and knowledge toward vaccines can influence public acceptance to some extent, however, the large base of non-medical students cannot be ignored. We aimed to investigate the knowledge, attitude, and willingness toward the COVID-19 vaccine among medical and non-medical students. Online surveys were completed by 652 medical students and 590 non-medical students to compare differences in knowledge and attitude of COVID-19 vaccine and vaccination willingness from three universities in the Zhejiang Province. The awareness rate of the vaccine among medical students (65.3%) was higher than that of non-medical students (53.6%). The approval rate of medical students for the safety and efficacy of the COVID-19 vaccine was higher than that of non-medical students. 81.8% of university students were willing to be vaccinated against COVID-19; Multiple stepwise regression analyses showed that lower class grades, rural students' origin, COVID-19 vaccine attitude and higher cognition level of health self-management influenced the acceptance of COVID-19 vaccination among medical students. However, urban origin, COVID-19 vaccine attitude were the factors hindering non-medical students' vaccination against COVID-19. The knowledge, attitude and willingness toward the COVID-19 vaccine on medical and non-medical students had different characteristics. Moreover, health self-management was associated with COVID-19 vaccination willingness. Staff involved in the university should pay more attention to the self-managementability of students, send out accurate and transparent information to enhance their cognitive level, further improving the students' willingness to receive the COVID-19 vaccine.

Reliability and validity of the Chinese version of the spiritual health scale.

BACKGROUND: In recent years, spiritual health became a focus of interest and nurses' spiritual health is crucial to the quality of their own lives and patients' health care. In China, high workloads, tense nurse-patient relationships, and low social status have been found to have negative impacts on the work attitude and nursing quality and spiritual health offers direction for solving this problem. This study assessed the spiritual health levels of nurses on the Chinese mainland using a revised Chinese version of the spiritual health scale (SHS-C). METHODS: A total of 747 nurses were recruited in Zhejiang Province, China. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) of the revised SHS-C were performed using convenience sampling, with 291 and 456 nurses used for each analysis type, respectively. Items on the SHS-C were screened using the discrete trend method, the extreme group approach, correlation analysis, and EFA to create a revised mental health questionnaire for nurses. An internal consistency test and CFA were then performed to verify the spiritual health questionnaire for nurses. A self-reporting questionnaire consisting of demographic questions and the revised SHS-C items was used for this cross-sectional correlation study. RESULTS: The revised SHS-C included 6 subscales comprising a total of 28 items. Cronbach's α and retest reliability for the revised questionnaire were 0.90 and 0.73, respectively. The fit of the model was analyzed by CFA [χ2/df =1.79; goodness of fit index (GFI) =0.83; adjusted GFI (AGFI) =0.79; root mean square error of approximation (RMSEA) =0.06; normed fit index (NFI) =0.86; comparative fit index (CFI) =0.93; non-NFI (NNFI) =0.92; incremental fit index (IFI) =0.93; parsimony NFI (PNFI) =0.76; parsimony CFI (PCFI) =0.83; and parsimony GFI (PGFI) =0.69; with each index score higher than those of the 5-subscale SHS short form previously developed by Hsiao et al.]. A reliability test showed that the overall Cronbach's α was 0.93, with a Cronbach's α of between 0.82 and 0.92 for each section. This study developed and validated a revised SHS-C. CONCLUSIONS: Our research will help policymakers, administrators, nursing leaders, and educators to identify areas for improvement regarding nurses' spiritual health, which could translate into significant improvements in patients' health care.

Development of a Resocialization Scale for Chinese Older Adult Migrants.

With a rapidly aging population in China, resocialization is a concern amidst an increasing influx of older adult migrants. The aim of the current study was to develop a resocialization assessment scale for older migrants within the Chinese context. The study was conducted in two phases. A literature review and qualitative interview were performed to generate a draft scale that was further examined through Delphi expert consultation. Participants comprised 509 older migrants selected for a questionnaire survey. Analysis identified 62 items across four factors: interpersonal relationships, behavioral patterns, cultural integration, and social roles. Reliability and validity of the resulting assessment scale were verified. The scale can be used to evaluate the degree of resocialization exhibited by older migrants in Chinese communities. [Research in Gerontological Nursing, 15(5), 245-253.].

In-Situ Oxidative Polymerization of Pyrrole Composited with Cellulose Nanocrystal by Reactive Ink-Jet Printing on Fiber Substrates.

A simple and novel method for the deposition of polypyrrole (PPy) and cellulose nanocrystal (CNC) composites on different fiber substrates by reactive ink-jet printing was proposed. PPy/CNCs composites were successfully prepared, and the surface resistance of conductive layer deposited on different fiber substrates is the least when the monomer concentration is 0.6 M. PPy/CNCs were deposited on polyethylene terephthalate (PET) to form a conductive layer by adding polyvinyl alcohol (PVA), and the optimum sintering temperature is 100 °C (monomer/PVA ratio 4.0, conductivity 0.769 S cm-1). The PPy/CNCs conductive layer deposited on the paper has the lowest surface resistance and the best adhesion, and the surface resistance of PPy/CNCs conductive layer decreases first and then increases with the increase of sulfonate concentration. Moreover, the volume of anion in sulfonate will affect the arrangement and aggregation of PPy molecular chain in composite materials. Appropriate sulfonate doping can improve the conductivity and stability of conductive paper, and the maximum conductivity is 0.813 S cm-1. Three devices based on PPy/CNCs conductive paper were proposed and fabricated. Therefore, this ink-jet printing provides a new method for the preparation of conductive materials, sensors, energy storage and electromagnetic shielding, etc.

Development and Validation of the Health Literacy Assessment Instrument for Patients with Chronic Pain.

A suitable health literacy assessment instrument for patients with chronic pain (HLCP) in China with good instrument's psychometric properties is required. A theoretical framework for the HLCP was developed by adopting the hierarchical model of health literacy proposed by Nutbeam. The reliability and validity of the HLCP were tested in a cross-sectional survey of 237 chronic pain patients from three pain clinics and wards of Grade-3A hospitals in Zhejiang Province, China. The discriminant degree method, correlation analysis method, factor analysis method (exploratory factor analysis), half reliability, and other methods were utilized to screen items for inclusion in the final version of HLCP, and the fitness of the model was subsequently evaluated by confirmatory factor analysis. Cronbach's alpha value and test-retest with two-week intervals were used to test the internal consistency and retest reliability of the HLCP. In the exploratory factor analysis, three domains, functional health literacy (10 items), interactive health literacy (14 items), and critical health literacy (7 items), comprising 31 items in total, were finally loaded; the model was determined to explain 70.9% of the total variance. HLCP's effective assessment of the health literacy level of patients with chronic pain and its acceptable reliability and validity were revealed through the results.

Flexible Temperature Sensors.

Temperature reflects the balance between production and dissipate of heat. Flexible temperature sensors are primary sensors used for temperature monitoring. To obtain real-time and accurate information of temperature, different flexible temperature sensors are developed according to the principle of flexible resistance temperature detector (FRTC), flexible thermocouple, flexible thermistor and flexible thermochromic, showing great potential in energy conversion and storage. In order to obtain high integration and multifunction, various flexible temperature sensors are studied and optimized, including active-matrix flexible temperature sensor, self-powered flexible temperature sensor, self-healing flexible temperature sensor and self-cleaning flexible temperature sensor. This review focuses on the structure, material, fabrication and performance of flexible temperature sensors. Also, some typical applications of flexible temperature sensors are discussed and summarized.

Theoretical studies on the noncovalent interaction of fructose and functionalized ionic liquids.

As a new kind of solvent and catalyst, the functionalized ionic liquids (ILs) had been successfully used in the conversion of fructose to high value-added biofuels. In this work, a detailed density functional theory (DFT) calculation had been carried out to investigate the interactions of fructose-ILs system. To study the effect of different anions and cations on the interaction with fructose, 25 different kinds of functionalized imidazolium-based ILs were calculated by using M06-2X-D3/6-311 + G** level. It was found that the interaction energies of fructose-anions were higher than those of the fructose-cations. The interaction will become stronger for the fructose and ILs when the alkyl chain of imidazolium-based cations was replaced with a functional group (COOH, OH or HSO3). However, when the length of the alkyl chain increased, it will result in a decrease in interaction energy due to the steric effect. In the anions (Y-SO3), the greater electronegativity of SO3 will lead to strong interaction with fructose. Also, this work simulates the interaction of fructose and ion pairs, with the results showing that hydrogen bonds (H-bonds) and π-stacking play an important role in the system. The present study provided basic aids to understand the structures and noncovalent interaction of fructose and functionalized ILs as well as the microscopic mechanism of fructose dissolution in the ILs.

Printable CsPbBr3 perovskite quantum dot ink for coffee ring-free fluorescent microarrays using inkjet printing.

Printable perovskite quantum dot (QD) ink is very important for achieving high quality coffee ring-free fluorescent microarrays for different kinds of emerging perovskite optoelectronic applications using inkjet printing. In this work, we prepared a printable CsPbBr3 perovskite QD ink by mixing high-boiling point dodecane with low-boiling point toluene as a solvent. The evaporation rate, viscosity and surface tension of the ink were carefully optimized by tuning the volume ratio of these two solvents for forming appropriate Marangoni flow, so as to balance the capillary flow and eliminate the coffee ring effect further. Successfully, CsPbBr3 perovskite microarrays with uniform surface, low roughness and no coffee rings were achieved by inkjet printing the optimized perovskite QD ink on a PVK (poly-(9-vinylcarbazole)) layer. Furthermore, we patterned the CsPbBr3 perovskite QD ink, and the printed patterns were only visible under ultraviolet (UV) light, which can be applied in invisible anti-counterfeiting labels and encryption in the future.

Evidence-based practice: Knowledge, attitudes, implementation, facilitators, and barriers among community nurses-systematic review.

BACKGROUND: This study is to summarize the status of knowledge, attitudes, implementation, facilitators, and barriers of evidence-based practice (EBP) in community nurses (CNs). EBP has been widely adopted but the knowledge, attitudes, and implementation of EBP among CNs, and the facilitators and barriers they perceived have not been clearly confirmed. METHODS: A literature search was conducted using combined keywords in 3 English databases and 3 Chinese databases of peer-reviewed publications covering the dates of publication from 1996 to July, 2018. Twenty articles were included. The information of the knowledge, attitudes, implementation, and the perceived facilitators and barriers of EBP in CNs was extracted and summarized. RESULTS: CNs had positive attitudes toward EBP, but insufficient knowledge and unprepared implementation. The most cited facilitators were academic training, management functions, and younger age. Inadequate time and resources were recognized as main barriers hindering the transforming from knowledge and attitudes to implementation. Developed interventions mainly focused on knowledge facilitation rather than the elimination of objective barriers. CONCLUSIONS: Findings demonstrate a compelling need for improvement in knowledge and implementation of EBP in CNs, compared with the better attitudes. Except education, knowledge translating into implementation needs more coordination with authorities to magnify the facilitators and overcome the barriers. Further studies need to concentrate on deficient knowledge and implementation of EBP among CNs. Policy makers can use the facilitators and barriers found by this review to modify nursing education, current scientific resources supplement, practice supports for care improving.

Printed and Flexible Capacitive Pressure Sensor with Carbon Nanotubes based Composite Dielectric Layer.

Flexible pressure sensors have attracted tremendous attention from researchers for their widely applications in tactile artificial intelligence, electric skin, disease diagnosis, and healthcare monitoring. Obtaining flexible pressure sensors with high sensitivity in a low cost and convenient way remains a huge challenge. In this paper, the composite dielectric layer based on the mixture of carbon nanotubes (CNTs) with different aspect ratios and polydimethylsiloxane (PDMS) was employed in flexible capacitive pressure sensor to increase its sensitivity. In addition, the screen printing instead of traditional etching based methods was used to prepare the electrodes array of the sensor. The results showed that the aspect ratio and weight fraction of the CNTs play an important role in improving the sensitivity of the printed capacitive pressure sensor. The prepared capacitive sensor with the CNTs/PDMS composite dielectric layer demonstrated a maximum sensitivity of 2.9 kPa-1 in the pressure range of 0-450 Pa, by using the CNTs with an aspect ratio of 1250-3750 and the weight fraction of 3.75%. The mechanism study revealed that the increase of the sensitivity of the pressure sensor should be attributed to the relative permittivity increase of the composite dielectric layer under pressure. Meanwhile, the printed 3 × 3 and 10 × 10 sensor arrays showed excellent spatial resolution and uniformity when they were applied to measure the pressure distribution. For further applications, the flexible pressure sensor was integrated on an adhesive bandage to detect the finger bending, as well as used to create Morse code by knocking the sensor to change their capacitance curves. The printed and flexible pressure sensor in this study might be a good candidate for the development of tactile artificial intelligence, intelligent medical diagnosis systems and wearable electronics.

Nano-Silver Ink of High Conductivity and Low Sintering Temperature for Paper Electronics.

Highly conductive ink with low sintering temperature is important for printed electronics on paper substrate. Silver nanoparticles (Ag NPs) of different average radii ranging from 48 to 176 nm were synthesized by adjusting the Ag+ concentration in the reaction process. The electric resistivity of the Ag NP-based ink film in relation to Ag NP size, sintering temperature, amount of PVP capping agent on Ag NP surface, and morphology evolution of the film during heating process was investigated. It was found that the resistivity of the films reduced very rapidly with increasing particle size due above all to reduced amount of protective agent capping on the Ag NPs. A semi-empirical relationship between the resistivity and the particle size was proposed. With the help of this mathematical expression, one gains both systematic and detailed insight to the resistivity evaluation with regard to the Ag particle size. The optimal electric resistivity of 4.6 µΩ cm was achieved at 140 °C for 10 min which was very close to the resistivity value of bulk Ag (1.58 µΩ cm). Mechanical flexibility of the printed electronics with the Ag NP-based ink on paper substrates was investigated. The prints on the art coated paper exhibited better flexibility compared to that on the photopaper. This might be attributed to the surface coating composition, surface morphology of the paper, and their corresponding ink absorption property.

Preparation and Application of Conductive Polyaniline-Coated Thermally Expandable Microspheres.

The thermally expandable microspheres (TEMs) were prepared through suspension polymerization with acrylonitrile (AN), methyl methacrylate (MMA) and methyl acrylate (MA) as the main monomers. Simultaneously, iso-pentane, n-hexane, iso-octane and other low-boiling hydrocarbons were prepared as blowing agents under two conditions, including high-pressure nitrogen and atmospheric conditions. The above physical foaming microspheres have a core-shell structure and excellent foaming effects. A layer of polyaniline (PANI) was deposited on the surface of the prepared TEMs by emulsion polymerization to obtain conductive and heat-expandable microspheres. Afterwards, the foaming ink was prepared by mixing the conductive TEMs and water-based ink. Finally, a conductive three-dimensional picture was obtained by screen-printing technology. This paper specifically focuses on the effects of particle size, morphology and the thermal expansion properties of the microspheres. The present research methods expect to obtain microspheres with a high foaming ratio, uniform particle size and antistatic properties, which may be applied to physical foaming ink.

Electronic effects of the substituent on the dioxygen-activating abilities of substituted iron tetraphenylporphyrins: a theoretical study.

A density functional theoretical (DFT) method was applied to understand the effects of the substituent on dioxygen activation by a series of substituted iron tetraphenylporphyrins [FeT(o/p-R)PP (o = ortho-substituted, p = para-substituted; R = -H, -Cl, -NO2, -CH3, -OCH3)]. The ground states (GS) of the dioxygen adducts of the substituted iron tetraphenylporphyrins [FeT(o/p-R)PPO2] were determined at the B3LYP/6-31G(d) level without any symmetry constraints. Binding energy calculations indicated that the presence of electron-withdrawing substituents at the para position favors O2 binding. Calculations of the O-O bond length of the adsorbed dioxygen revealed that the influence of the p-substituent on the activation of dioxygen decreases in the order p-CH3 > p-Cl > p-OCH3 > -H > p-NO2, while the influence of the o-substituent decreases in the order o-NO2 > o-CH3 > o-Cl > o-OCH3 > -H. The low-lying excited states (LLES) of the FeT(o/p-R)PPO2 adducts suggest that the ability to activate dioxygen decreases in the order o-CH3 > o-OCH3 = -H > o-NO2 > o-Cl for o-substituents and p-CH3 > p-Cl > -H > p-NO2 > p-OCH3 for p-substituents. NBO charge population analysis and spin density analysis showed that substitution caused more ß-electrons to be transferred from the iron tetraphenylporphyrin to the dioxygen, which enhanced dioxygen activation. Spin density analysis confirmed that the ß-electron population at the adsorbed dioxygen is an accurate indicator of the degree of dioxygen activation. The trend observed in porphyrin catalytic activity as the substituent on the dioxygen adduct was varied is consistent with the trend in the binding energy. It is clear that substituents at the ortho and para positions in these dioxygen adducts play different roles in dioxygen activation.