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Abstract Despite years of concerted research efforts, an industrial-scale technology has yet to emerge for production and conversion of algal biomass into biofuels and bioproducts. The objective of this review is to explore the ways of possible integration of biology, ecology and engineering for sustainable large algal cultivation and biofuel production systems. Beside the costs of nutrients, such as nitrogen and phosphorous, and fresh water, upstream technologies which are not ready for commercialization both impede economic feasibility and conflict with the ecological benefits in the sector. Focusing mainly on the engineering side of chemical conversion of algae to biodiesel has also become obstacle. However, to reduce the costs, one potential strategy has been progressing steadily to synergistically link algal aquaculture to the governmentally mandated reduction of nitrogen and phosphorous concentrations in municipal wastewater. Recent research also supports the suppositions of scalability and cost reduction. Noticeably, less is known of the economic impact of conversion of the whole algae-based biorefinery sector with additional biochemical and thermochemical processes and integration with ecological constraints. This review finds that a biorefinery approach with integrated biology, ecology, and engineering could lead to a feasible algal-based technology for variety of biofuels and bioproducts.

Algae are often promoted as feedstock organisms to produce a sustainable petroleum fossil fuel alternative. However, to induce lipid accumulation most often requires a severe stress that is difficult to induce in large batch cultures. The objective of this study is to analyze and mathematically model heat stress on growth, chlorophyll content, triacylglyceride, and starch synthesis in algae. We initially screened 30 algal species for the most pronounced induction of lipid droplets from heat stress using confocal microscopy and mass spectroscopy techniques. One species, Coccomyxa subellipsoidea C169, was selected and subjected to further biochemical analyses using a jacketed bioreactor amended with 1% CO2 at 25°C, 30°C, 32°C, 33°C, 34°C, 35°C, and 36°C. Lipid and starch accumulation was less extreme than N stress. Growth was reduced above 25°C, but heat stress induced lipid droplet synthesis was negatively correlated with growth only past a demonstrated threshold temperature above 32°C. The optimal temperature for lipid accumulation was 35°C, which led to 6% of dry weight triglyceride content and a 72% reduction from optimal growth after 5 days. Fatty acid influx rates into triglycerides and 15N labeling of amino acids and proteins indicate that heat stress is mechanistically distinct from N stress. Thus, this study lends support to a novel hypothesis that lipid droplet triglycerides result from a redistribution of carbon flux as fatty acids to neutral storage lipids over membrane or other lipids.

Some critical trends in information theory, its role in living systems and utilization in fluctuation theory are discussed. The mutual information of thermodynamic coupling is incorporated into the generalized fluctuation theorem by using information theory and nonequilibrium thermodynamics. Thermodynamically coupled dissipative structures in living systems are capable of degrading more energy, and processing complex information through developmental and environmental constraints. The generalized fluctuation theorem can quantify the hysteresis observed in the amount of the irreversible work in nonequilibrium regimes in the presence of information and thermodynamic coupling.

Aim: Patent ductus arteriosus (PDA) is a frequent health problem in premature infants. Pharmacologic closure is recommended only for hemodynamically significant PDA (hsPDA) that is defined according to the clinical and echocardiographic criteria. The aim of this study was to explore the value of commonly used criteria in defining hsPDA and predicting the required number of courses of ibuprofen treatment to close PDA in premature infants. Methods: Sixty premature infants with a gestational age of ≤33 weeks were evaluated prospectively. Clinical and echocardiographic criteria [O2 requirement, ductus diameter (DD) and left atrial-to-aortic root diameter ratio (LA:Ao)] were used to define hsPDA. Clinical improvement after pharmacologic closure of PDA and association between the criteria and required number of ibuprofen courses were investigated. Results: O2 requirement decreased by PDA closure but was not different between patients with hsPDA and the others with PDA. Also, O2 requirement was not found to be associated with required number of ibuprofen courses. DD and LA:Ao were greater in patients with hsPDA. DD was found to be associated with required number of courses of ibuprofen treatment. Conclusion: Although there was an improvement in O2 requirement with PDA closure, echocardiographic criteria were found to be more valuable in defining hsPDA. DD should also be used to estimate the duration of treatment.

ObjectiveTo investigate the early neonatal outcomes of very-low-birth-weight (VLBW) infants discharged home from neonatal intensive care units (NICUs) in Turkey.Material and methodsA prospective cohort study was performed between April 1, 2016 and April 30, 2017. The study included VLBW infants admitted to level III NICUs. Perinatal and neonatal data of all infants born with a birth weight of ≤1500 g were collected for infants who survived.ResultsData from 69 NICUs were obtained. The mean birth weight and gestational age were 1137±245 g and 29±2.4 weeks, respectively. During the study period, 78% of VLBW infants survived to discharge and 48% of survived infants had no major neonatal morbidity. VLBW infants who survived were evaluated in terms of major morbidities: bronchopulmonary dysplasia was detected in 23.7% of infants, necrotizing enterocolitis in 9.1%, blood culture proven late-onset sepsis (LOS) in 21.1%, blood culture negative LOS in 21.3%, severe intraventricular hemorrhage in 5.4% and severe retinopathy of prematurity in 11.1%. Hemodynamically significant patent ductus arteriosus was diagnosed in 24.8% of infants. Antenatal steroids were administered to 42.9% of mothers.ConclusionThe present investigation is the first multicenter study to include epidemiological information on VLBW infants in Turkey. Morbidity rate in VLBW infants is a serious concern and higher than those in developed countries. Implementation of oxygen therapy with appropriate monitoring, better antenatal and neonatal care and control of sepsis may reduce the prevalence of neonatal morbidities. Therefore, monitoring standards of neonatal care and implementing quality improvement projects across the country are essential for improving neonatal outcomes in Turkish NICUs.

Neonatal thromboembolic events are rare, and only a few cases of intrauterine spontaneous arterial thromboembolisms have been reported in the literature. Thrombolytic therapy with recombinant tissue plasminogen activator is usually the preferred treatment because it has a short half-life, fewer systemic side effects, and a strong, specific affinity for fibrin. Protocols vary from center to center, but there is still no consensus regarding the proper dosage or treatment duration. Herein, we present the case of an intrauterine spontaneous arterial thromboembolism in a preterm infant that completely resolved after being treated with low-dose recombinant tissue plasminogen activator (0.02 mg/kg/h).