Enhanced recovery after fetal spina bifida surgery: what is our global practice?

OBJECTIVE: Prenatal spina bifida closure results in improved outcomes for the child compared to postnatal surgery but is associated with significant maternal morbidity. Optimization of the perioperative care for women who underwent fetal spina bifida surgery could improve maternal and pregnancy outcomes. Enhanced Recovery After Surgery (ERAS) protocols are multimodal, evidence-based care plans that have been adopted for multiple surgical procedures to promote faster and better patient recovery and shorter hospitalization. This study aims to explore if fetal centers have implemented ERAS principles in this setting. Furthermore, we provide recommendations for the perioperative management of patients undergoing fetal spina bifida surgery. METHODS: Fifty-three fetal therapy centers offering prenatal surgery for open spina bifida were identified and invited to complete a digital questionnaire covering their pre-, intra- and postoperative management. An overall score was calculated per center based on the center's compliance with 20 key ERAS principles, extrapolated from ERAS guidelines for cesarean section, gynecologic oncology and colorectal surgery. Each item was scored 1 or 0 when the center did or did not comply with each principle, with a maximum score of 20. RESULTS: The questionnaire was completed by 46 centers in 17 countries (response rate 87%). Twenty-two centers (48%) exclusively perform open fetal surgery (laparotomy and hysterotomy), whereas 14 (30%) offer both open and fetoscopic procedures and 10 (22%) use fetoscopy only. The perioperative management of patients undergoing fetoscopic and open surgery was highly similar. The median ERAS score was 12 (mean 12.5, SD 2.4, range 8-17). Center compliance was the highest for the use of regional anesthesia (98%), avoidance of bowel preparation (96%), and thromboprophylaxis (96%), while the lowest compliance was achieved for preoperative carbohydrate loading (15%), postoperative nausea and vomiting prevention (33%), avoidance of overnight fasting (33%) and a 2-hour fasting period for clear fluids (20%). ERAS scores were similar in centers with a short (2-5 days), medium (6-10 days) and long (≥11 days) hospital stay (12.8 ± 2.4, 12.1 ± 2.0, and 10.3 ± 3.2, respectively, p=0.15). Furthermore, there was no significant association between ERAS score and surgical technique or center volume. CONCLUSION: The perioperative management of fetal spina bifida surgery is highly variable across fetal therapy centers worldwide. Standardizing protocols according to ERAS principles may improve patient recovery, reduce maternal morbidity, and shorten hospital stay after fetal spina bifida surgery. This article is protected by copyright. All rights reserved.

Differential photosynthetic plasticity of Amazonian tree species in response to light environments.

To investigate how and to what extent there are differences in the photosynthetic plasticity of trees in response to different light environments, six species from three successional groups (late successional, mid-successional, and pioneers) were exposed to three different light environments [deep shade - DS (5% full sunlight - FS), moderate shade - MS (35% FS) and full sunlight - FS]. Maximum net photosynthesis (Amax), leaf N partitioning, stomatal, mesophile, and biochemical limitations (SL, ML, and BL, respectively), carboxylation velocity (Vcmax), and electron transport (Jmax) rates, and the state of photosynthetic induction (IS) were evaluated. Higher values of Amax, Vcmax, and Jmax in FS were observed for pioneer species, which invested the largest amount of leaf N in Rubisco. The lower IS for pioneer species reveals its reduced ability to take advantage of sunflecks. In general, the main photosynthetic limitations are diffusive, with SL and ML having equal importance under FS, and ML decreasing along with irradiance. The leaf traits, which are more determinant of the photosynthetic process, respond independently in relation to the successional group, especially with low light availability. An effective partitioning of leaf N between photosynthetic and structural components played a crucial role in the acclimation process and determined the increase or decrease of photosynthesis in response to the light conditions.

The "Sniffin' Kids-PT" test: A smell test variant for Portuguese children.

OBJECTIVE: Olfactory tests tailored for children are essential, as diagnosing olfactory dysfunction at these ages can be challenging. The 16-item "Sniffin' Sticks" is reliable and easy to perform. To the best of our knowledge, there is currently no validated olfactory test for the Portuguese pediatric population. This study aimed to adapt and validate the "Sniffin' Sticks" olfactory test for the Portuguese pediatric population. METHODS: Between August 2020 and September 2021, 354 children aged between 6 and 17years old enrolled in the study, 336 healthy children with a normal sense of smell, and 18 anosmic children with Kallmann syndrome. The study consisted of two parts. Firstly, the "Sniffin' Sticks" olfactory identification test was applied to healthy children and the odors with statistically significant low identification rates were excluded. A modified version of "Sniffin' Sticks" was defined and named "Sniffin' Kids-PT" test. Secondly, normative data were assessed and test-retest and validation tests were performed. RESULTS: Apple and Cloves odors were identified with a low rate and were excluded from the "Sniffin' Sticks" olfactory test. In the modified 14-item "Sniffin' Kids-PT", scoring <6 (from 6-8years old), <7 (from 9-11years old) or <8 (from 12-14years old and 15-17years old) was indicative of olfactory dysfunction. The test-retest reliability was good (r=0.81; P<0.001) and the differences between scores of healthy children and anosmic children were statistically significant (U213=13.00; P<0.001). CONCLUSION: The modified "Sniffin' Kids-PT" is a reliable test to discriminate between normosmia and olfactory dysfunction in Portuguese children over 5years old.

Spectrally Sharp Near-Field Thermal Emission: Revealing Some Disagreements between a Casimir-Polder Sensor and Predictions from Far-Field Emittance.

Near-field thermal emission largely exceeds blackbody radiation, owing to spectrally sharp emission in surface polaritons. We turn the Casimir-Polder interaction between Cs(7P_{1/2}) and a sapphire interface into a sensor sharply filtering, at 24.687 THz, the near-field sapphire emission at ∼24.5 THz. The temperature evolution of the sapphire mode is demonstrated. The Cs sensor, sensitive to both dispersion and dissipation, suggests the polariton to be redshifted and sharper, as compared, up to 1100 K, to predictions from far-field sapphire emission, affected by birefringence and multiple resonances.

Visible Occlusal Plaque Index Predicting Caries Lesion Activity.

This study was undertaken to appraise the predictive validity of the Visible Occlusal Plaque Index (VOPI) in assessing occlusal caries lesion activity in adolescents. A total of 618 adolescents aged 10 to 15 y were examined at the beginning of the trial and 511 (82.7%) at the 2-y follow-up. Adolescents and parents answered questionnaires about demographics, oral health behavior, and family sociodemographic variables. The VOPI has a 4-point ordinal scale ranging from no plaque to heavy plaque. Molar teeth were assigned to group VOPI 0-1 (no/thin plaque; n = 2,539) and group VOPI 2-3 (thick/heavy plaque; n = 843). At baseline examination, occlusal surfaces at risk of transition (n = 3,382) were either sound (55%), inactive noncavitated lesions (21%), inactive cavitated lesions (1%), active noncavitated lesions (15%), or active cavitated lesions (7%). The relative risk (RR) for caries lesion transition was estimated. Sound occlusal surfaces with no or thin plaque were significantly more likely to remain sound (RR = 1.3; 95% confidence interval [CI]: 1.1-1.4) than those harboring thick or heavy plaque. Inactive noncavitated occlusal lesions presenting no or thin plaque were significantly less likely to progress to active noncavitated lesions (RR = 0.1; CI: 0.0-0.8) than their counterparts with thick or heavy plaque. Active noncavitated lesions harboring thick and heavy plaque had a significantly lowest chance of becoming sound (RR = 0.7; CI: 0.5-0.9) and a highest risk of remaining active (RR = 1.5; CI: 1.1-1.9). Stepwise logistic regression analyses were run according to surface status at baseline and showed that none of the nonclinical predictors were significant for the outcome. The presence of thick and heavy plaque on occlusal surfaces was a predictor for caries lesion development, progression and activity (P < 0.0001). In conclusion, besides being an additional clinical tool for oral hygiene assessment, the VOPI is a predictor for development, progression, and activity of occlusal caries lesion. This is of particular interest for assessment of occlusal lesions undergoing health-promoting transitions.

Carbetocin vs. oxytocin at elective caesarean delivery: a double-blind, randomised, controlled, non-inferiority trial of low- and high-dose regimens.

Carbetocin or oxytocin are given routinely as first-line uterotonic drugs following delivery of the neonate during caesarean delivery to prevent postpartum haemorrhage. Low doses may be as effective as high doses with a potential reduction in adverse effects. In this double-blind, randomised, controlled, non-inferiority trial, we assigned low-risk patients undergoing elective caesarean delivery under spinal anaesthesia to one of four groups: carbetocin 20 µg; carbetocin 100 µg; oxytocin 0.5 IU bolus + infusion; and oxytocin 5 IU bolus + infusion. The study drug was given intravenously after delivery of the neonate. Uterine tone was assessed by the obstetrician 2, 5 and 10 minutes after study drug administration according to an 11-point verbal numerical rating scale (0 = atonic, 10 = excellent tone). The primary outcome measure was uterine tone 2 min after study drug administration. The pre-specified non-inferiority margin was 1.2 points on the 11-point scale. Secondary outcomes included uterine tone after 5 and 10 minutes, use of additional uterotonics, blood loss and adverse effects. Data were available for 277 patients. Carbetocin 20 µg resulting in uterine tone of (median (IQR [range])) 8 (7-8 [1-10]) was non-inferior to carbetocin 100 µg with tone 8 (7-9 [3-10]), median (95%CI) difference 0 (-0.44-0.44). Similarly, oxytocin 0.5 IU with tone 7 (6-8 [3-10]) was non-inferior to oxytocin 5 IU with tone 8 (6-8 [2-10]), median (95%CI) difference 1 (0.11-1.89). Carbetocin 20 µg was also non-inferior to oxytocin 5 IU, and oxytocin 0.5 IU was non-inferior to carbetocin 100 µg. Uterine tone after 5 and 10 minutes, use of additional uterotonics, blood loss and adverse effects were similar in all groups.

Growth curve of Nile tilapia from different families of the AquaAmérica variety / Curva de crescimento de tilápia-do-Nilo de diferentes famílias da variedade AquaAmérica

Selection can affect growth, changing performance and asymptotic values. However, there is little information about the growth of families in fish breeding programs. The aim of this study was to evaluate the performance and growth of families of Nile tilapia AquaAmérica. Twenty AquaAmérica families cultivated in a net cage (13.5 m3) for 181 days were evaluated. The nonlinear Gompertz regression model was fitted to the data by the weighted least squares method, taking the inverse of the variance of weight in different families and at different ages as the weighting variable. The model was adjusted to describe the growth in weight and morphometric characteristics. Two families showed highest (P<0.05) weights at both 133 days (family AA10: 743.2 g; family AA16: 741.2 g) and 181 days (family AA10: 1,422.1 g; family AA16: 1,393.4 g) of the experiment. In both experimental periods, the males showed a heavier weight, with the greatest contrast between the sexes occurring at 181 days. The analysis of the three most contrasting families (AA1, AA9 and AA14) showed that the asymptotic value for weight was higher (P<0.05) in family AA9 (3,926.3 g) than in family AA14 (3,251.6 g), but specific growth rate and age at the inflection point did not differ significantly between families. In conclusion, two of the 20 families were superior; males exhibited a greater growth, mainly in the period of 181 days; and the growth curve differed between the families, especially for asymptotic weight.

A seleção pode impactar a forma de crescimento, mudando o desempenho e os valores assintóticos. No entanto, existem poucas informações sobre o crescimento das famílias em programas de criação de peixes. O objetivo deste estudo foi examinar o desempenho e as curvas de crescimento de famílias de tilápia-do-Nilo AquaAmérica. Foram avaliadas 20 famílias AquaAmérica cultivadas em tanques-rede (13,5 m3) por 181 dias. O modelo de regressão não linear de Gompertz foi ajustado aos dados pelo método dos mínimos quadrados ponderados, tomando o inverso da variância do peso nas diferentes famílias e nas diferentes idades como variável de ponderação. O modelo foi ajustado para descrever o crescimento em peso e características morfométricas. Duas famílias apresentaram pesos maiores (P <0,05) em 133 dias (família AA10: 743,2 g; família AA16: 741,2 g) e 181 dias (família AA10: 1422,1 g; família AA16: 1393,4 g) de experimento em relação a outras famílias. Em ambos os períodos experimentais, os machos apresentaram maior peso, com maior contraste entre os sexos ocorrendo aos 181 dias. A análise das três famílias mais contrastantes (AA1, AA9 e AA14) mostrou que o valor assintótico para o peso foi maior (P <0,05) na família AA9 (3926,3 g) do que na família AA14 (3251,6 g), mas a taxa de crescimento específica e a idade no ponto de inflexão não diferiu significativamente entre as famílias. Em conclusão, duas das 20 famílias eram muito superiores; machos exibiram um maior crescimento, principalmente no período de 181 dias; e a curva de crescimento diferiu entre as famílias, principalmente quanto ao peso assintótico.

Growth curve of Nile tilapia from different families of the AquaAmérica variety / Curva de crescimento de tilápia-do-Nilo de diferentes famílias da variedade AquaAmérica

Selection can affect growth, changing performance and asymptotic values. However, there is little information about the growth of families in fish breeding programs. The aim of this study was to evaluate the performance and growth of families of Nile tilapia AquaAmérica. Twenty AquaAmérica families cultivated in a net cage (13.5 m3) for 181 days were evaluated. The nonlinear Gompertz regression model was fitted to the data by the weighted least squares method, taking the inverse of the variance of weight in different families and at different ages as the weighting variable. The model was adjusted to describe the growth in weight and morphometric characteristics. Two families showed highest (P<0.05) weights at both 133 days (family AA10: 743.2 g; family AA16: 741.2 g) and 181 days (family AA10: 1,422.1 g; family AA16: 1,393.4 g) of the experiment. In both experimental periods, the males showed a heavier weight, with the greatest contrast between the sexes occurring at 181 days. The analysis of the three most contrasting families (AA1, AA9 and AA14) showed that the asymptotic value for weight was higher (P<0.05) in family AA9 (3,926.3 g) than in family AA14 (3,251.6 g), but specific growth rate and age at the inflection point did not differ significantly between families. In conclusion, two of the 20 families were superior; males exhibited a greater growth, mainly in the period of 181 days; and the growth curve differed between the families, especially for asymptotic weight.

A seleção pode impactar a forma de crescimento, mudando o desempenho e os valores assintóticos. No entanto, existem poucas informações sobre o crescimento das famílias em programas de criação de peixes. O objetivo deste estudo foi examinar o desempenho e as curvas de crescimento de famílias de tilápia-do-Nilo AquaAmérica. Foram avaliadas 20 famílias AquaAmérica cultivadas em tanques-rede (13,5 m3) por 181 dias. O modelo de regressão não linear de Gompertz foi ajustado aos dados pelo método dos mínimos quadrados ponderados, tomando o inverso da variância do peso nas diferentes famílias e nas diferentes idades como variável de ponderação. O modelo foi ajustado para descrever o crescimento em peso e características morfométricas. Duas famílias apresentaram pesos maiores (P <0,05) em 133 dias (família AA10: 743,2 g; família AA16: 741,2 g) e 181 dias (família AA10: 1422,1 g; família AA16: 1393,4 g) de experimento em relação a outras famílias. Em ambos os períodos experimentais, os machos apresentaram maior peso, com maior contraste entre os sexos ocorrendo aos 181 dias. A análise das três famílias mais contrastantes (AA1, AA9 e AA14) mostrou que o valor assintótico para o peso foi maior (P <0,05) na família AA9 (3926,3 g) do que na família AA14 (3251,6 g), mas a taxa de crescimento específica e a idade no ponto de inflexão não diferiu significativamente entre as famílias. Em conclusão, duas das 20 famílias eram muito superiores; machos exibiram um maior crescimento, principalmente no período de 181 dias; e a curva de crescimento diferiu entre as famílias, principalmente quanto ao peso assintótico.

Growth curve of Nile tilapia from different families of the AquaAmérica variety

Abstract Selection can affect growth, changing performance and asymptotic values. However, there is little information about the growth of families in fish breeding programs. The aim of this study was to evaluate the performance and growth of families of Nile tilapia AquaAmérica. Twenty AquaAmérica families cultivated in a net cage (13.5 m3) for 181 days were evaluated. The nonlinear Gompertz regression model was fitted to the data by the weighted least squares method, taking the inverse of the variance of weight in different families and at different ages as the weighting variable. The model was adjusted to describe the growth in weight and morphometric characteristics. Two families showed highest (P 0.05) weights at both 133 days (family AA10: 743.2 g; family AA16: 741.2 g) and 181 days (family AA10: 1,422.1 g; family AA16: 1,393.4 g) of the experiment. In both experimental periods, the males showed a heavier weight, with the greatest contrast between the sexes occurring at 181 days. The analysis of the three most contrasting families (AA1, AA9 and AA14) showed that the asymptotic value for weight was higher (P 0.05) in family AA9 (3,926.3 g) than in family AA14 (3,251.6 g), but specific growth rate and age at the inflection point did not differ significantly between families. In conclusion, two of the 20 families were superior; males exhibited a greater growth, mainly in the period of 181 days; and the growth curve differed between the families, especially for asymptotic weight.

Resumo A seleção pode impactar a forma de crescimento, mudando o desempenho e os valores assintóticos. No entanto, existem poucas informações sobre o crescimento das famílias em programas de criação de peixes. O objetivo deste estudo foi examinar o desempenho e as curvas de crescimento de famílias de tilápia-do-Nilo AquaAmérica. Foram avaliadas 20 famílias AquaAmérica cultivadas em tanques-rede (13,5 m3) por 181 dias. O modelo de regressão não linear de Gompertz foi ajustado aos dados pelo método dos mínimos quadrados ponderados, tomando o inverso da variância do peso nas diferentes famílias e nas diferentes idades como variável de ponderação. O modelo foi ajustado para descrever o crescimento em peso e características morfométricas. Duas famílias apresentaram pesos maiores (P 0,05) em 133 dias (família AA10: 743,2 g; família AA16: 741,2 g) e 181 dias (família AA10: 1422,1 g; família AA16: 1393,4 g) de experimento em relação a outras famílias. Em ambos os períodos experimentais, os machos apresentaram maior peso, com maior contraste entre os sexos ocorrendo aos 181 dias. A análise das três famílias mais contrastantes (AA1, AA9 e AA14) mostrou que o valor assintótico para o peso foi maior (P 0,05) na família AA9 (3926,3 g) do que na família AA14 (3251,6 g), mas a taxa de crescimento específica e a idade no ponto de inflexão não diferiu significativamente entre as famílias. Em conclusão, duas das 20 famílias eram muito superiores; machos exibiram um maior crescimento, principalmente no período de 181 dias; e a curva de crescimento diferiu entre as famílias, principalmente quanto ao peso assintótico.

Linear Probing of Molecules at Micrometric Distances from a Surface with Sub-Doppler Frequency Resolution.

We report on precision spectroscopy of subwavelength confined molecular gases. This was obtained by rovibrational selective reflection of NH_{3} and SF_{6} gases using a quantum cascade laser at λ≈10.6 µm. Our technique probes molecules at micrometric distances (≈λ/2π) from the window of a macroscopic cell with submegahertz resolution, allowing molecule-surface interaction spectroscopy. We exploit the linearity and high resolution of our technique to gain novel spectroscopic information on the SF_{6} greenhouse gas, useful for enriching molecular databases. The natural extension of our work to thin cells will allow compact frequency references and improved measurements of the Casimir-Polder interaction with molecules.

Surface response around a sharply resonant surface polariton mode is simply a Lorentzian.

At the planar interface between a material and vacuum, the complex surface response S(ω)=[ε(ω)-1]/[ε(ω)+1], with ε(ω) being the relative complex dielectric permittivity of the material, exhibits resonances typical of the surface polariton modes, when ε(ω)∼-1. We show that for a moderately sharp resonance, S(ω) is satisfactorily described with a mere (complex) Lorentzian, independent of the details affecting the various bulk resonances describing ε(ω). Remarkably, this implies a quantitative correlation between the resonant behaviors of ℜe[S(ω)] and ℑm[S(ω)], respectively, associated to the dispersive and dissipative effects in the surface near-field. We show that this "strong resonance" approximation easily applies and discuss its limits, based on published data for sapphire, CaF2, and BaF2. An extension to interfaces between two media or to a non-planar interface is briefly considered.

Growth curve of Nile tilapia from different families of the AquaAmérica variety.

Selection can affect growth, changing performance and asymptotic values. However, there is little information about the growth of families in fish breeding programs. The aim of this study was to evaluate the performance and growth of families of Nile tilapia AquaAmérica. Twenty AquaAmérica families cultivated in a net cage (13.5 m3) for 181 days were evaluated. The nonlinear Gompertz regression model was fitted to the data by the weighted least squares method, taking the inverse of the variance of weight in different families and at different ages as the weighting variable. The model was adjusted to describe the growth in weight and morphometric characteristics. Two families showed highest (P<0.05) weights at both 133 days (family AA10: 743.2 g; family AA16: 741.2 g) and 181 days (family AA10: 1,422.1 g; family AA16: 1,393.4 g) of the experiment. In both experimental periods, the males showed a heavier weight, with the greatest contrast between the sexes occurring at 181 days. The analysis of the three most contrasting families (AA1, AA9 and AA14) showed that the asymptotic value for weight was higher (P<0.05) in family AA9 (3,926.3 g) than in family AA14 (3,251.6 g), but specific growth rate and age at the inflection point did not differ significantly between families. In conclusion, two of the 20 families were superior; males exhibited a greater growth, mainly in the period of 181 days; and the growth curve differed between the families, especially for asymptotic weight.

The association of shock index and haemoglobin variation with postpartum haemorrhage after vaginal delivery: a prospective cohort pilot study.

INTRODUCTION: Shock index and continuous non-invasive haemoglobin monitoring (SpHb) have both been proposed for the timely recognition of postpartum haemorrhage (PPH). We sought to determine, in parallel, the association of each of shock index and SpHb with blood loss after vaginal delivery. METHODS: Sixty-six women were recruited to this prospective observational study. Shock index and SpHb were recorded postpartum for 120 min. The association between each of shock index and SpHb with quantitative blood loss (QBL) at 30, 60 and 120 min postpartum was determined using linear mixed models. Area-under-the-receiver-operator-characteristic (AUROC) curves were constructed to evaluate the diagnostic ability of shock index and SpHb to detect PPH (defined as QBL ≥1000 mL). RESULTS: Shock index trend was associated with QBL over the first 30 min (r=0.37, P=0.002), but not over 60 or 120 min. There was an association of SpHb trend with QBL over the first 30 min (P=0.06), but not over 60 min (r=-0.32, P=0.009) or 120 min (r=-0.26, P=0.03). Maximum shock index within 60 min correlated with QBL (r=0.54, P <0.001) and was a predictor of PPH (P=0.0012, AUROC 0.796). Maximum change in SpHb within 60 min negatively correlated with QBL (r=-0.4, P <0.001) and was a predictor of PPH (P=0.048, AUROC 0.761). CONCLUSIONS: The trend of shock index and its peak values are associated with blood loss after vaginal delivery and are early indicators of PPH. Negative trend of SpHb is a late sign of PPH and has a weaker association with blood loss than shock index.

Oxytocin at elective caesarean delivery: a dose-finding study in women with obesity.

Prophylactic oxytocin administration at the third stage of labour reduces blood loss and the need for additional uterotonic drugs. Obesity is known to be associated with an increased risk of uterine atony and postpartum haemorrhage. It is unknown whether women with obesity require higher doses of oxytocin in order to achieve adequate uterine tone after delivery. The purpose of this study was to establish the bolus dose of oxytocin required to initiate effective uterine contraction in 90% of women with obesity (the ED90 ) at elective caesarean delivery. We conducted a double-blind dose-finding study using the biased coin up-down design method. Term pregnant women with a BMI ≥ 40 kg.m-2 undergoing elective caesarean delivery under regional anaesthesia were included. Those with conditions predisposing to postpartum haemorrhage were not included. Oxytocin was administered as an intravenous bolus over 1 minute upon delivery of the fetus. With the first woman receiving 0.5 IU, oxytocin doses were administered according to a sequential allocation scheme. The primary outcome measure was satisfactory uterine tone, as assessed by the operating obstetrician 2 minutes after administration of the oxytocin bolus. Secondary outcomes included the need for rescue uterotonic drugs, adverse effects and estimated blood loss. We studied 30 women with a mean (SD) BMI of 52.3 (7.6) kg.m-2 . The ED90 for oxytocin was 0.75 IU (95%CI 0.5-0.93 IU) by isotonic regression and 0.78 IU (95%CI 0.68-0.88 IU) by the Dixon and Mood method. Our results suggest that women with a BMI ≥ 40 kg.m-2 require approximately twice as much oxytocin as those with a BMI < 40 kg.m-2 , in whom an ED90 of 0.35 IU (95%CI 0.15-0.52 IU) has previously been demonstrated.

Production of arachidonic acid by Mortierella alpina using wastes from potato chips industry.

AIMS: This research aimed to determine the potential use of wastes from the potato chips industry as a carbon source to develop an economical culture medium for the production of biomass, lipids and arachidonic acid (ARA) by Mortierella alpina. METHODS AND RESULTS: A synthetic culture medium was optimized using a Plackett-Burman and central composite rotatable design, and used as a base to evaluate and characterize the potential use of wastes from the potato chips industry as carbon sources for the production of biomass, lipids and ARA by M. alpina. The waste was selected among other solid and liquid hydrolysed residues/by-products, and local low-cost alternatives for nitrogen sources were also evaluated. After 6 days of fermentation, the biomass concentration reached 20 g l-1 with 40% of total lipids, and a 35% ARA content in the lipids fraction. Savings in production were calculated using a sensitivity analysis for the alternative culture medium in different scenarios. CONCLUSIONS: This study showed a 7% savings in culture media expenses in the production of ARA-enriched biomass of M. alpina, compared to the conventional synthetic culture medium, when waste from the potato chips industry was used as an alternative source of carbon and macro/microelements, supplemented with a low-cost yeast extract alternative. SIGNIFICANCE AND IMPACT OF THE STUDY: The demonstration of the use of potato chips wastes as a low-cost carbon source for the biomass, lipids and ARA production, suggesting an eco-friendly alternative for the use of agri-food wastes for valuable metabolites production.

Technological mapping and trends in photobioreactors for the production of microalgae.

Photobioreactors (PBRs) are equipment of central importance for the massive cultivation of microalgae, providing controlled conditions for high cell productivity. There are a few popular PBR designs, with contrasting advantages and limitations, such as poor light distribution, mass transfer, or hydrodynamic behavior. Due to the environmental concerns in recent decades and the discovery of new, useful microalgal metabolites, the interest in finding alternatives to solve technological bottlenecks of PBRs has intensified. In this process, new geometries, materials, and modes of light supply were developed, generating a significant scientific and technological output, reported in papers and patents. We present a technological landscape analysis of photobioreactor design, focusing on improvements of the classical geometries and trends in industrial photobioreactors. The analysis of 412 patent documents showed a surge in innovation filing since 2005 and a reduction in the number of new documents along the last decade. The recent efforts in design improvement, the leading countries, institutes and companies that innovate, and the trends in PBR technology are presented and discussed.