The effect of slow breathing exercise on heart rate and blood pressure in patients undergoing percutaneous coronary intervention: a randomized controlled trial.

AIM: To determine the effects of slow breathing exercise (SBE) on heart rate (HR) and blood pressure (BP) in patients after percutaneous coronary intervention (PCI). METHODS AND RESULTS: The study is a single-blind, randomized controlled trial. Seventy-eight eligible patients after primary PCI were divided randomly into either the control group or the trial group. The control group only received routine post-PCI care. In addition to routine care, participants in the trial group performed SBE at home, two to three times for a total of 30 min every day for 12 weeks. The main outcomes were HR and BP measured in the office and at home. The secondary outcome was compliance with the breathing exercise. Patients allocated to the trial group, on average, performed 5.21 days/week for 26.00 min/day. The trial group showed a significant reduction in HR of 3.95 b.p.m. (P = 0.004) measured in the office. The reduction in HR measured in the office was greater for the trial group, with a significant difference between the two groups (P = 0.005). There was no significant difference between the two groups in HR measured at home. There was also no significant difference in BP measured in the office or at home between the two groups. CONCLUSION: Slow breathing exercise is an effective non-pharmacological method to reduce HR in patients undergoing PCI. Further study is needed to confirm whether the intervention is effective on BP. REGISTRATION: The trial was registered at the Chinese Clinical Trial Registry: ChiCTR-IOR-17012525.

A Qualitative Exploration of the Psychological Experience of Patients Hospitalized With COVID-19.

This qualitative study describes the psychological experience of patients hospitalized with COVID-19. These patients went through 3 psychological stages: extremely uncertainties during the initial diagnostic stage, complicated feelings of negativity during the treatment stage, and positive growth in the recovery stage. It is important for nurses to provide holistic care.

Optimization of micronutrient supplement for enhancing biogas production from food waste in two-phase thermophilic anaerobic digestion.

The aim of this study was to enhance the biogas productivity of two-phase thermophilic anaerobic digestion (AD) using food waste (FW) as the primary substrate. The influence of adding four trace metals (Ca, Mg, Co, and Ni) as micronutrient supplement in the methanogenic phase of the thermophilic system was investigated. Initially, Response Surface Methodology (RSM) was applied to determine the optimal concentration of micronutrients in batch experiments. The results showed that optimal concentrations of 303, 777, 7 and 3mg/L of Ca, Mg, Co and Ni, respectively, increased the biogas productivity as much as 50% and significantly reduced the processing time. The formulated supplement was tested in continuous two-phase thermophilic AD system with regard to process stability and productivity. It was found that a destabilized thermophilic AD process encountering high VFA accumulation recovered in less than two weeks, while the biogas production was improved by 40% yielding 0.46L CH4/gVSadded/day. There was also a major increase in soluble COD utilization upon the addition of micronutrient supplement. The results of this study indicate that a micronutrient supplement containing Ca, Mg, Co and Ni could probably remedy any type of thermophilic AD process.

Co-composting of horticultural waste with fruit peels, food waste, and soybean residues.

Horticultural waste was co-composted with fruit peels, food waste, and soybean residues individually to evaluate the effects of these easily available organic wastes in Singapore on the composting process and product quality. Each co-composting material was mixed with horticultural waste in the wet weight ratio of 1:1 and composted for 46 days. Results showed that all co-composting materials accelerated the degradation of total carbon and resulted in higher nutrients of nitrogen (N), phosphorous (P), and potassium (K) in the final product compared with horticultural waste alone. Mixture with fruit peels achieved the fastest total carbon loss; however, did not reach the minimum required temperature for pathogen destruction. The end product was found to be the best source for K and had a higher pH that could be used for the remediation of acidic soil. Food waste resulted in the highest available nitrate (NO3-N) content in the end product, but caused high salt content, total coliforms, and slower total carbon loss initially. Soybean residues were found to be the best co-composting material to produce compost with high N, P, and K when compared with other materials due to the highest temperature, fastest total carbon loss, fastest reduction in C/N ratio, and best conservation of nutrients.

Urban nutrient recovery from fresh human urine through cultivation of Chlorella sorokiniana.

High rate food consumption in urban cities causes vast amounts of nitrogen and phosphorus used in agriculture to end up in urban wastewaters. To substantially recover these nutrients, source-separated human urine should be targeted. The present study was to investigate the feasibility of recovering nitrogen and phosphorus in urine via microalgae cultivation. In concentrated urine, urea hydrolysis and precipitation occur rapidly, making microalgal growth difficult and nutrient recovery ineffective. However, when fresh urine was added as nutrient stock for 1-day growth requirement, biomass of Chlorella sorokiniana grew from 0.44 to 0.96 g L(-1) utilising 62.64 mg L(-1) of N and 10.64 mg L(-1) of P, achieving 80.4% and 96.6% recoveries, respectively in a 1-day non-sterile cultivation cycle. Overall, microalgae grown with urine added as nutrient supplement show no signs of inferiority as compared to those grown in recipe medium BG11 in terms of mass and chlorophyll a growth rates as well as resulting lipids (36.8%) and energy contents (21.0 kJ g(-1)).

Characterization of induced struvite formation from source-separated urine using seawater and brine as magnesium sources.

Struvite (MgNH4PO4·6H2O) precipitation is widely used for nutrient recovery from source-separated urine in view of limited natural resources. Spontaneous struvite formation depletes the magnesium in hydrolyzed urine so that additional magnesium source is required to produce induced struvite for P-recovery. The present study investigated the morphology and purity of induced struvite crystals obtained from hydrolyzed urine by using seawater and desalination brine as low cost magnesium sources. The results demonstrated that both seawater and brine were effective magnesium sources to recover phosphorus from hydrolyzed urine. Crystals obtained from synthetic and real urine were revealed that the morphology was feather and coffin shape, respectively. Structural characterization of the precipitates confirmed that crystallized struvite was the main product. However, co-precipitates magnesium calcite and calcite were observed when seawater was added into synthetic and real urine, respectively. It was found that the presence of calcium in the magnesium sources could compromise struvite purity. Higher struvite purity could be obtained with higher Mg/Ca ratio in the magnesium source. Comparative analysis indicated that seawater and brine had similar effect on the crystallized struvite purity.

A strategy for urban outdoor production of high-concentration algal biomass for green biorefining.

The present study was to investigate the feasibility of carrying out effective microalgae cultivation and high-rate tertiary wastewater treatment simultaneously in a vertical sequencing batch photobioreactor with small areal footprint, suitable for sustainable urban microalgae production. For 15 consecutive days, Chlorella sorokiniana was cultivated in synthetic wastewater under various trophic conditions. A cycle of 12-h heterotrophic: 12-h mixotrophic condition produced 0.98 g l(-1) d(-1) of algal biomass in tandem with a 94.7% removal of 254.4 mg l(-1) C-acetate, a 100% removal of 84.7 mg l(-1) N-NH4 and a removal of 15.0 mg l(-1) P-PO4. The cells were harvested via cost-effective chitosan flocculation with multiple dosing (3 times) applying established chitosan:cell ratio (1:300 w/w) and pH control (6.3-6.8). Reproducible flocculation efficiencies of greater than 99% and high-concentration algal broths (>20% solids) were achieved.

Biotransformation of vegetable and fruit processing wastes into yeast biomass enriched with selenium.

Water extracts of cabbage, watermelon, a mixture of residual biomass of green salads and tropical fruits were used for yeast cultivation. These extracts contained from 1420 to 8900 mg/l of dissolved organic matter, and from 600 to 1800 mg/l of nitrogen. pH of the extracts was in the range from 4.1 to 6.4. Biomass concentration of yeast, Saccharomyces cerevisiae CEE 12 grown at 30 degrees C for 96 h in the sterilized extracts without any nutrient supplements was from 6.4 to 8.2 g/l; content of protein was from 40% to 45% of dry biomass. The yield was comparable with the yield of yeast biomass grown in potato dextrose broth. The biomass can be considered as the protein source. Its feed value was enhanced by incorporation of selenium in biomass to the level of 150 microg/g of dry biomass. Therefore, it was recommended to transform the extracts from vegetable and fruit processing wastes into the yeast biomass enriched with selenium.