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STUDY QUESTION Can additional genetic variants for circulating anti-Müllerian hormone (AMH) levels be identified through a genome-wide association study (GWAS) meta-analysis including a large sample of premenopausal women? SUMMARY ANSWER We identified four loci associated with AMH levels at P < 5 × 10−8: the previously reported MCM8 locus and three novel signals in or near AMH, TEX41 and CDCA7. WHAT IS KNOWN ALREADY AMH is expressed by antral stage ovarian follicles in women, and variation in age-specific circulating AMH levels has been associated with disease outcomes. However, the physiological mechanisms underlying these AMH-disease associations are largely unknown. STUDY DESIGN, SIZE, DURATION We performed a GWAS meta-analysis in which we combined summary statistics of a previous AMH GWAS with GWAS data from 3705 additional women from three different cohorts. PARTICIPANTS/MATERIALS, SETTING, METHODS In total, we included data from 7049 premenopausal female participants of European ancestry. The median age of study participants ranged from 15.3 to 48 years across cohorts. Circulating AMH levels were measured in either serum or plasma samples using different ELISA assays. Study-specific analyses were adjusted for age at blood collection and population stratification, and summary statistics were meta-analysed using a standard error-weighted approach. Subsequently, we functionally annotated GWAS variants that reached genome-wide significance (P < 5 × 10−8). We also performed a gene-based GWAS, pathway analysis and linkage disequilibrium score regression and Mendelian randomization (MR) analyses. MAIN RESULTS AND THE ROLE OF CHANCE We identified four loci associated with AMH levels at P < 5 × 10−8: the previously reported MCM8 locus and three novel signals in or near AMH, TEX41 and CDCA7. The strongest signal was a missense variant in the AMH gene (rs10417628). Most prioritized genes at the other three identified loci were involved in cell cycle regulation. Genetic correlation analyses indicated a strong positive correlation among single nucleotide polymorphisms for AMH levels and for age at menopause (rg = 0.82, FDR = 0.003). Exploratory two-sample MR analyses did not support causal effects of AMH on breast cancer or polycystic ovary syndrome risk, but should be interpreted with caution as they may be underpowered and the validity of genetic instruments could not be extensively explored. LARGE SCALE DATA The full AMH GWAS summary statistics will made available after publication through the GWAS catalog (https://www.ebi.ac.uk/gwas/). LIMITATIONS, REASONS FOR CAUTION Whilst this study doubled the sample size of the most recent GWAS, the statistical power is still relatively low. As a result, we may still lack power to identify more genetic variants for AMH and to determine causal effects of AMH on, for example, breast cancer. Also, follow-up studies are needed to investigate whether the signal for the AMH gene is caused by reduced AMH detection by certain assays instead of actual lower circulating AMH levels. WIDER IMPLICATIONS OF THE FINDINGS Genes mapped to the MCM8, TEX41 and CDCA7 loci are involved in the cell cycle and processes such as DNA replication and apoptosis. The mechanism underlying their associations with AMH may affect the size of the ovarian follicle pool. Altogether, our results provide more insight into the biology of AMH and, accordingly, the biological processes involved in ovarian ageing. STUDY FUNDING/COMPETING INTEREST(S) Nurses’ Health Study and Nurses’ Health Study II were supported by research grants from the National Institutes of Health (CA172726, CA186107, CA50385, CA87969, CA49449, CA67262, CA178949). The UK Medical Research Council and Wellcome (217065/Z/19/Z) and the University of Bristol provide core support for ALSPAC. This publication is the work of the listed authors, who will serve as guarantors for the contents of this article. A comprehensive list of grants funding is available on the ALSPAC website (http://www.bristol.ac.uk/alspac/external/documents/grant-acknowledgements.pdf). Funding for the collection of genotype and phenotype data used here was provided by the British Heart Foundation (SP/07/008/24066), Wellcome (WT092830M and WT08806) and UK Medical Research Council (G1001357). M.C.B., A.L.G.S. and D.A.L. work in a unit that is funded by the University of Bristol and UK Medical Research Council (MC_UU_00011/6). M.C.B.’s contribution to this work was funded by a UK Medical Research Council Skills Development Fellowship (MR/P014054/1) and D.A.L. is a National Institute of Health Research Senior Investigator (NF-0616-10102). A.L.G.S. was supported by the study of Dynamic longitudinal exposome trajectories in cardiovascular and metabolic non-communicable diseases (H2020-SC1-2019-Single-Stage-RTD, project ID 874739). The Doetinchem Cohort Study was financially supported by the Ministry of Health, Welfare and Sports of the Netherlands. The funder had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. Ansh Labs performed the AMH measurements for the Doetinchem Cohort Study free of charge. Ansh Labs was not involved in the data analysis, interpretation or reporting, nor was it financially involved in any aspect of the study. R.M.G.V. was funded by the Honours Track of MSc Epidemiology, University Medical Center Utrecht with a grant from the Netherlands Organization for Scientific Research (NWO) (022.005.021). The Study of Women's Health Across the Nation (SWAN) has grant support from the National Institutes of Health (NIH), DHHS, through the National Institute on Aging (NIA), the National Institute of Nursing Research (NINR) and the NIH Office of Research on Women’s Health (ORWH) (U01NR004061; U01AG012505, U01AG012535, U01AG012531, U01AG012539, U01AG012546, U01AG012553, U01AG012554, U01AG012495). The SWAN Genomic Analyses and SWAN Legacy have grant support from the NIA (U01AG017719). The Generations Study was funded by Breast Cancer Now and the Institute of Cancer Research (ICR). The ICR acknowledges NHS funding to the NIHR Biomedical Research Centre. The content of this manuscript is solely the responsibility of the authors and does not necessarily represent official views of the funders. The Sister Study was funded by the Intramural Research Program of the National Institutes of Health (NIH), National Institute of Environmental Health Sciences (Z01-ES044005 to D.P.S.); the AMH assays were supported by the Avon Foundation (02-2012-065 to H.B. Nichols and D.P.S.). The breast cancer genome-wide association analyses were supported by the Government of Canada through Genome Canada and the Canadian Institutes of Health Research, the ‘Ministère de l’Économie, de la Science et de l’Innovation du Québec’ through Genome Québec and grant PSR-SIIRI-701, The National Institutes of Health (U19 CA148065, X01HG007492), Cancer Research UK (C1287/A10118, C1287/A16563, C1287/A10710) and The European Union (HEALTH-F2-2009-223175 and H2020 633784 and 634935). All studies and funders are listed in Michailidou et al. (Nature, 2017). F.J.M.B. has received fees and grant support from Merck Serono and Ferring BV. D.A.L. has received financial support from several national and international government and charitable funders as well as from Medtronic Ltd and Roche Diagnostics for research that is unrelated to this study. N.S. is scientific consultant for Ansh Laboratories. The other authors declare no competing interests.

In a patient with Usher syndrome and atypical muscle complaints, we have identified two separate variants in MYO7A andNEB genes by exome sequencing. The homozygous variants in these two recessive genes could explain the full phenotype of our patient., In a patient with Usher syndrome and atypical muscle complaints, we have identified two separate variants in MYO7A and NEB genes by exome sequencing. The homozygous variants in these two recessive genes could explain the full phenotype of our patient.

Microalgae are widely used in the bioremediation of wastewaters due to their efficient removal of pollutants such as nitrogen, phosphorus, and contaminants of emerging concern (CECs). Siloxanes are CECs that reach wastewater treatment plants (WWTPs), leading to the production of biogas enriched with these compounds, associated with the breakdown of cogeneration equipment. The biological removal of siloxanes from wastewaters could be a sustainable alternative to the costly existing technologies, but no investigation has been performed using microalgal cultures for this purpose. This study evaluated the ability of Chlorella vulgaris to bioremediate primary (PE) and secondary (SE) urban effluents and remove volatile methylsiloxanes (VMSs). C. vulgaris grew successfully in both effluents, and approximately 86% of nitrogen and 80% of phosphorus were efficiently removed from the PE, while 52% of nitrogen and 87% of phosphorus were removed from the SE, and the presence of VMSs does not seem to have a negative influence on nutrient removal. Three out of the seven of the analysed VMSs were detected in the microalgal biomass at the end of the PE assay. However, dodecamethylcyclohexasiloxane (D6) was the one that accumulated to a greater extent, since 48% of the initial mass of D6 was detected in the biomass samples. D6 is one of the most lipophilic VMSs, which might contribute to the higher adsorption onto the surface of microalgae. Overall, the results indicate C. vulgaris’ potential to remove specific VMSs from effluents.

This work proposes distinct configurations for tubular photobioreactors (PBRs) illuminated with specific and adequate light wavelength provided by LEDs. The PBRs are characterized by an involute/flat reflective surface around/below a cylindrical borosilicate glass tube that is illuminated by a LEDs panel located above. Reflectors can enlarge the absorber tube's illuminated area, enabling a uniform (spatial and temporal) light distribution across the culture vessel. Additionally, high-energy-efficient LEDs can minimize heat generation and energetic-related costs. Coupling these two factors can result in higher light utilization efficiency and photosynthetic activity. Depending on the reflector design, almost all the light arriving at the collector aperture can be collected and available for microalgal cultivation. Chlorella vulgaris (C. vulgaris) growth was evaluated as a function of the reflector geometry (flat (F), simple double parabola (SP) and traditional double parabola (DP)) and material (anodized aluminum with (MS) and without (R85) protective coating and stainless steel (SS)). C. vulgaris growth as a function of time was found to be in good agreement with the actinometric results, where the parabolic reflectors (SP and DP) made of higher specular reflectance materials (R85 and MS) were the most efficient systems. Conversely, energy-based specific growth rates slightly increased as the photon flux decreased, signaling an energetic efficiency loss due to the low transmissibility of microalgal suspensions. Additional tests using two absorber tubes (spaced between 12.5 and 75.0 mm) over the R85-F reflector were also carried out, showing that the distance of 50.0 mm led to the best compromise between the specific growth rates and biomass productivities per square meter of solar collector. Under these conditions, higher efficiency on the photonic energy usage was attained compared to the single-tube test.

RASGRP2 encodes the calcium and diacylglycerol (DAG)-regulated guanine nucleotide exchange factor I (CalDAG-GEFI) identified as a Rap1-activating molecule. Pathogenic variants previously identified in RASGRP2 allowed the characterization of CalDAG-GEFI deficiency as a non-syndromic, autosomal recessive platelet function disease. We report on the clinical manifestations and laboratory features of a Portuguese family with a likely pathogenic variant in RASGRP2 (c.999G>C leading to a p.Lys333Asn change in the CDC25 catalytic domain of CalDAG-GEFI) and discuss the contribution of this variant to the disease manifestations. Based on the study of this family with one homozygous patient and five heterozygous carriers and on a critical analysis of the literature, we challenge previous knowledge that CalDAG-GEFI deficiency only manifests in homozygous patients. Our data suggest that at least for the RASGRP2 variant reported herein, there is a phenotypic expression, albeit milder, in heterozygous carriers.

Study question Should sperm aneuploidies and sperm DNA fragmentation (sDNAfrag) be included as valid tests in the routine investigation of male infertility? Summary answer Sperm DNA fragmentation was associated with male age, oligozoospermia (OZ), oligoteratozoospermia (OT), astenoteratozoospermia (AT) and oligoastenoteratozoospermia (OAT). Sperm aneuploidies were associated with OT and OAT. What is known already Semen parameters assist male infertility diagnosis and treatment, but sDNAfrag and aneuploidy analysis could add useful information, as abnormal values compromise fertility. To include these tests in the routine diagnosis it should be determined if behave as informative parameter and add information regarding the fertility status. For that, further studies comparing these tests to semen parameters are needed, since previous results are not consensual. Additionally, standardization of a sDNAfrag cut-off is needed, as different sample sizes and techniques originate distinct results. Also, until a standardization of the protocol is missing, a cut-off value should be defined for each laboratory. Study design, size, duration A retrospective and prospective investigation was performed, within a 12 years period (April 2007-December 2019). A total of 835 infertile males with a normal karyotype (46,XY) were included. Karyotyping and evaluation of sDNAfrag and sperm aneuploidies were made at a public Genetic unit. All normozoospermic (NZ) patients with a born child and patients whose infertility treatments were done due to female factors were selected from our database and used as controls (60 individuals). Participants/materials, setting, methods Semen analysis followed WHO–2010 guidelines. sDNAfrag was evaluated using the TUNEL assay. Sperm aneuploidies were detected using FISH (chromosomes 13, 18, 21, X, Y). Several tests were applied: correlations for linear associations between numerical variables, ANOVA for comparisons between means, Dunn-test for post-hoc comparisons. To determine the sDNAfrag cut-off value, the area under the ROC curve, sensitivity and specificity, were calculated, with the Youden-Index used to find a threshold that maximizes both sensitivity and specificity. Main results and the role of chance Regarding male age, it was observed a positive correlation with sperm concentration, a negative correlation with sperm vitality (VT) and hypoosmolality, and a positive correlation with sDNAfrag. Regarding sDNAfrag, it was observed negative correlation with sperm concentration, total progressive motility (TPM), morphology, VT and hypoosmolality. Regarding sperm aneuploidies, both total sperm aneuploidy and total sperm disomy exhibited a negative association with sperm concentration, TPM and morphology. It was also investigated whose groups of individuals could be indicated for sDNAfrag or sperm aneuploidy testing. The NZ group evidenced significant lower sDNAfrag, total sperm aneuploidy and total sperm disomy in relation to the non-NZ group. In the NZ group, sDNAfrag was significantly lower in relation to the OZ, OT, AT and OAT groups. The NZ group presented significant lower percentages of sperm aneuploidy in relation to the OT and OAT groups, and significant lower percentages of sperm disomy in relation to the OAT group. Additionally, sDNAfrag was positively correlated with total sperm aneuploidy and total sperm disomy. From the present large population, ROC curve analysis allowed estimating a cut-off value of 18.8% for the TUNEL-assay (sDNAfrag), with 0.658 of area under the curve, 53.9% sensitivity and 76.7% specificity. Limitations, reasons for caution Although presenting a high number of cases and strict controls, the present study was unable to include as controls healthy men with proven fertility. Additionally, the present study did not take into account life-style factors and male associated pathologies besides infertility. Wider implications of the findings: Semen parameters were shown to be negatively correlated with sDNAfrag and sperm aneuploidies. As sDNAfrag testing and sperm aneuploidy testing were associated with semen abnormalities and male age, it is suggested their inclusion in the routine evaluation of infertile men, thus adding important complementary information about the fertility status. Trial registration number Not Appliable

X-linked myotubular myopathy (XLMTM), a centronuclear congenital myopathy secondary to pathogenic variants in the MTM1 gene encoding myotubularin, is typically recognized for its classic and severe phenotype which includes neonatal hypotonia, severe muscle weakness, long-term ventilator dependence, markedly delayed gross motor milestones with inability to independently ambulate, and a high neonatal and childhood mortality. However, milder congenital forms of the condition and other phenotypes are recognized. We describe a 6-year-old boy with a mild XLMTM phenotype with independent gait and no respiratory insufficiency even in the neonatal period. The child has a hemizygous novel splice site variant in the MTM1 gene (c.232–25A > T) whose pathogenicity was confirmed by cDNA studies (exon 5 skipping) and muscle biopsy findings. We also compared the phenotype of our patient with the few reported cases that presented a mild XLMTM phenotype and no respiratory distress at birth, and discussed the potential mechanisms underlying this phenotype such as the presence of residual expression of the normal myotubularin transcript.

Microalgal biorefineries have been proposed as an excellent opportunity to take advantage of the wealthy composition of microalgal biomass and sustainably supply the market needs with a wide diversity of compounds (e.g., lipids, carbohydrates, proteins, pigments, vitamins and antioxidants). Although very promising, microalgal biorefineries present some limitations that should be addressed for successful deployment at scale. These include the scalability of the process and challenges faced within the microalgal biomass production and processing chain: (i) laboratory-scale experiments to define microalgal strain and optimal conditions for attaining high biomass and target compounds' productivities; (ii) improvement of biomass productivities and induction of target products' accumulation through the selection of an adequate cultivation system and operation mode; and (iii) selection of adequate downstream processes for biomass recovery, cell disruption and product extraction, taking into account the market value and regulations established for the target compounds. This chapter highlights the main challenges and process options faced in each step of microalgal biorefineries.

The connection between tourism and nature justifies the environmental concerns from tourism agents, namely global hotel chains. This paper explores the differences between smaller hotel chains and their larger global counterparts regarding environmentally sustainable practices. The research approach is qualitative, based on the analysis of 40 company websites and in-depth interviews with 18 entrepreneurs and executives. Results suggest that environmental issues are, for most companies, not a response to societal challenges (‘doing the right thing’), but a response to owners’ concerns (‘doing things right’). Hotel chains develop environmental sustainability practices, mainly for cost-reduction purposes, accommodating the owners’ demands for efficiency. Notwithstanding, there are differences according to the chain’s size. Smaller companies are less prone to adopt environmental practices and to invest in communicating them than global chains. Concerning sustainability in the hotel industry, most studies focus on specific topics and discussions. A more holistic approach to sustainability to establish a deeper understanding of sustainable business decisions in the hotel sector is scarce in the literature. This paper addresses this gap by exploring the strategic reasons behind the sustainable practices of hotel companies, namely smaller ones. Managerial implications of the results are also derived in this paper.

Leachates treatment relies on the adoption of a multi-barrier strategy, involving primary, secondary, and tertiary processes. Due to their ability to grow in a wide variety of environmental conditions, and their nutritional requirements, especially in terms of nitrogen and phosphorus, microalgae appear as a promising alternative for the tertiary treatment of landfill leachates. Despite these advantages, only a few studies have promoted landfill leachates treatment using microalgae, most of them emphasizing the need for effluent dilution in water to minimize the toxicity and high color/turbidity of these effluents. An option to avoid the use of freshwater for effluent dilution would be the development of novel photobioreactors (PBRs), able to improve light absorption and, hence, light utilization efficiency by microalgae. This study evaluated the potential of Chlorella vulgaris and Tetradesmus obliquus on nitrogen (in the forms of nitrate and nitrite) removal from a pre-treated landfill leachate. Preliminary experiments using different concentrations of the pre-treated leachate were carried out in 1-L flasks. These results have shown that microalgal growth and nitrogen removal were higher in more diluted conditions. After selection of the adequate effluent concentration, a tubular PBR coupled to an optical reflector was used for biomass production. This innovative PBR is known to improve light distribution along the tube perimeter, enhancing microalgal photosynthetic activity. In fact, a significant improvement in C. vulgaris biomass productivities and nitrogen species removal efficiencies was observed in this PBR, confirming its potential as an effective platform for microalgal biomass production and tertiary treatment of landfill leachates.

The global population is expected to rise from seven to nine billion by 2050, which will create challenges to sustainable development. This rapid population growth will increase the pressure on natural resources, mainly for energy and food supply. Regarding food supply, the development of food industry and food-related activities contributes to the intensification of water use, with the consequent increase in wastewater produced, which needs to be properly treated. At the same time, to meet these demands for increased food supplies, it is important to improve the productivity of food crops and soil fertility. Finally, livestock and aquaculture production processes should reduce their dependence on feed supplies obtained from food crops. To meet these broad-spectrum goals related to food industry processes, the use of microalgal cultures may be a valuable alternative, as microalgae are photosynthetic microorganisms known for their enormous potential in several applications, including: (1) nutrient assimilation from different wastewaters; (2) CO2 capture from the atmosphere or industrial gaseous emissions; and (3) source of biologically active metabolites with potential for use in agriculture and in the cosmetics, pharmaceutical, food, feed, and biofuel industries. Considering these undeniable benefits, this chapter highlights how microalgal cultures, biomass, and metabolites can contribute to food industry applications, beyond direct human consumption.

The Kingdom of Portugal was established with the help of military-monastic orders, which provided important defence against Muslim armies during the 12th–13th century Christian conquest. While historical sources document the main events of this period, this research seeks to elucidate individual lifestyles and movement, aspects typically absent from written records. A multi-isotopic approach was used on skeletal material from eight Christian and two Muslim burials from Evora, Portugal (11th–13th centuries). Anthropological and archaeological evidence suggests the Christian adults belonged to the Evora Militia, which we seek to confirm through the reconstructed diet and mobility of these individuals. Stable carbon, nitrogen and sulphur isotopes were measured in bone collagen, and radiogenic strontium, carbonate stable oxygen and apatite stable carbon isotopes were measured in tooth enamel. Results of the stable oxygen and radiogenic strontium isotopes indicated diverse origins of the Christian population, while at least one individual was local. The Muslim adult was local, as anticipated. The δ13Cen (enamel) values provide evidence of childhood consumption of different cereals (C3 and C4), possibly linked to social status. The δ13Ccol (bone collagen) human values indicated mostly C3 diets with varying inputs of C4, while δ15N reflected high protein intake overall. The mean diet-consumer spacing of this population was compared to other isotopic studies from Medieval Iberia and other European monastic/convent populations. A visible trend emerged in populations that likely followed religious fasting rules, including the Evora Christians. The results of this study indicate that the Order of Evora was composed of members from diverse geographic and possibly social origins, an aspect previously unclear in written sources.

Although very promising, the use of microalgae for CO2 capture still faces some limitations. Due to the low solubility of this gas in the liquid medium, poor CO2 utilisation efficiencies by microalgae are very common, resulting in low CO2 fixation rates and CO2 losses to the atmosphere. Considering this limitation, several researchers have focused on improving photobioreactor (PBR) design to increase CO2 gas-liquid mass transfer rates. However, these systems typically rely on high fluid turbulence and power consumption due to CO2 gas compression. As an alternative, this study proposes using an oscillatory flow reactor with smooth periodic constrictions (OFR-SPC). So far, this reactor design has been successfully applied to improve the mixing efficiency of several chemical processes. However, there is no evidence of its use for microalgal cultivation. To evaluate its potential for microalgal biomass production, a detailed characterisation of CO2 mass transfer was performed. CO2 mass transfer and bubbles’ dynamics were evaluated under different operational conditions: (i) oscillation amplitude and frequency; (ii) aeration rate; (iii) CO2 concentration in the inlet gas; and (iv) biomass concentration. This study made it possible to understand the effect of each process variable on the individual values of liquid-side mass transfer coefficient, k L , and specific interfacial area, a . According to the results, CO2 gas-liquid mass transfer was enhanced by increasing the oscillatory movement, aeration rate and CO2 concentration. Moreover, this study demonstrated that promising CO2 mass transfer rates can be achieved without significantly increasing power consumption and fluid turbulence.

This study investigated the impact of varying concentrations of tetracycline on the performance of mixed microalgae-bacteria photo-bioreactors. Photo-bioreactors were assessed for their ability to remove carbon dioxide (CO2) from the biogas of anaerobic membrane bioreactor (anMBR), and nutrients from the anaerobic effluent. The varying concentrations of tetracycline had no impact on the removal of CO2 from biogas. 29% v/v of CO2 was completely removed to generate > 20% v/v of oxygen (O2) in all reactors. Removal of nutrients and biomass was not affected at low concentrations of tetracycline (≤ 150 μg/L), but 20 mg/L of tetracycline lowered the biomass generation and removal efficiencies of phosphate. Conversely, high chlorophyll a and b content was observed at 20 mg/L of tetracycline. High tetracycline level had no impact on the diversity of 18S rRNA gene-based microalgal communities but adversely affected the 16S rRNA gene-based microbial communities. Specifically, both Proteobacteria and Bacteroidetes phyla decreased in relative abundance but not phylum Chloroplast. Additionally, both nitrogen-fixing (e.g. Flavobacterium, unclassified Burkholderiales and unclassified Rhizobiaceae) and denitrifying groups (e.g. Hydrogenophaga spp.) were significantly reduced in relative abundance at high tetracycline concentration. Phosphate-accumulating microorganisms, Acinetobacter spp. and Pseudomonas spp. were similarly reduced upon exposure to high tetracycline concentration. Unclassified Comamonadaceae, however, increased in relative abundance, which correlated with an increase in the abundance of tetracycline resistance genes associated with efflux pump mechanism. Overall, the findings demonstrate that antibiotic concentrations in municipal wastewaters will not significantly affect the removal of nutrients by the mixed microalgae-bacteria photo-bioreactors. However, utilizing such photo-bioreactors as a polishing step for anMBRs that treat wastewaters with high tetracycline concentration may not be effective as evidenced from the lower nutrient removal and occurrence of antibiotic resistance genes.

The increase in carbon dioxide (CO2) emissions to the atmosphere is provoking an environmental crisis, as CO2 is considered the main responsible for the greenhouse effect and, consequently, global warming. The constant search for effective systems to capture CO2 has revealed the potential of microalgal cultures to perform this task. Microalgae are photosynthetic microrganisms able to uptake CO2 from both the atmosphere and flue gas emissions, converting it into biomass or other organic compounds. One important advantage of microalgae is that they present higher specific growth rates and biomass productivities than other photosynthetic organisms, such as terrestrial plants. This chapter presents an overview of the main studies aiming to evaluate the performance of microalgae for CO2 capture from the atmosphere or flue gas emissions. Also, the main limitations of using these microrganisms are described, highlighting the main research needs.

Microalgae have attracted the attention of several researchers, due to the undeniable potential of these microorganisms in several applications. Microalgae can be used in environmental applications, such as CO2 capture from the atmosphere or flue gas emissions, and in the removal of nutrients and pollutants from different wastewaters. They can also be used in the energetic sector, as a renewable energy source. Due to their very rich composition in terms of proteins, vitamins, lipids, polyunsaturated fatty acids, and other valuable compounds, microalgae can be used as raw material for several industries, such as food and feed, pharmaceuticals, and cosmetics. Despite the advantages of microalgal culturing, commercialization of microalgal biomass and products is still not economically feasible, particularly due to the costs associated to microalgal recovery/harvesting (which typically account for 20%–30% of overall production costs). Microalgal growth in dilute suspensions (0.02%–0.05% dry solids), similar densities between microalgal cells and the culture medium, and small-sized (

BACKGROUND Alongside with the development of hand held equipment, echo is becoming more accessible to nontraditional settings. General and family medicine (GPs) are at the forefront of any health system, but the use of cardiac echo by GPs is still unexplored. PURPOSE: This study aims to evaluate the accuracy of echocardiography assessment performed as an extension of the physical exam by GPs. METHODS: Two GPs underwent standard echocardiography training for 6 months. Subsequently, patients with diabetes or arterial hypertension were submitted to an echocardiogram performed by their GPs using a pocket ultrasound. Views obtained (with and without color Doppler) were parasternal long and short axis, apical and subcostal, with measurements of the posterior wall (PW), interventricular septum (IVS), left ventricle (LV), left atrium (LA), aorta and inferior vena cava (IVC). Studies were reviewed at the workstation and measured by two experts who classified the exams according to the image quality. RESULTS: Sixty echocardiograms were analyzed (mean age of 61y, 42% females and 58% males). In 50% the image quality was considered sufficient, 42% considered good and 8% considered bad. There were statistically significant differences between the GPs and expert measurements on the sinus of Valsalva (30.3 ± 3 to 28.8 ± 3.1mm, p = 0.001), LV in systole (p

Microalgae and cyanobacteria have a wide range of applications, going from food industry to wastewater treatment. Although microalgal cultivation has been studied for more than half a century, their applicability in large scale is still prohibitive. Microalgal harvesting remains a critical point due to microalgae small size, high growth rates (which implies frequent harvesting), and the higher costs and energy consumption. In this sense, immobilization methods have been applied to microalgae to solve the problems associated to suspended growth systems. Accordingly, microalgal biofilms emerged as a cost-effective and ecologically safe solution, as they can remove nutrients and heavy metals from wastewaters and also produce biomass that can be used for the production of valuable compounds. A detailed description of microalgal applications, harvesting techniques, and biofilm formation is reviewed in this chapter. Additionally, the application of microalgal biofilms on wastewater treatment is discussed in more detail.

This paper presents results on the research currently being carried out with the objective of developing new electrochemistry-based processes to produce renewable synthetic fuels from liquefied biomass. In the current research line, the gas mixtures obtained from the typical electrolysis are not separated into their components but rather are introduced into a reactor together with liquefied biomass, at atmospheric pressure and different temperatures, under acidified zeolite Y catalyst, to obtain synthesis gas. This gaseous mixture has several applications, like the production of synthetic 2nd generation biofuel (e. g., biomethane, biomethanol, bio-dimethyl ether, formic acid, etc.). The behaviour of operational parameters such as biomass content, temperature and the use of different amounts of acidified zeolite HY catalyst were investigated. In the performed tests, it was found that, in addition to the synthesis gas (hydrogen, oxygen, carbon monoxide and carbon dioxide), methane was also obtained. Therefore, this research is quite promising, and the most favourable results were obtained by carrying out the biomass test at 300 °C, together with 4% of acidified zeolite Y catalyst, which gives a methane volumetric concentration equal to 35%.

Humanity is facing some major global threats, namely lack of environmental sustainability, the energy crisis associated with the unsustainable reliance on fossil fuels, and water scarcity, which will be exacerbated with the rapid growth of urban areas. Researchers have drawn their attention to microalgae, photosynthetic microorganisms known for their environmental applications, such as wastewater remediation and lipids accumulation, to produce third-generation biofuels to solve some of these major issues. Considering this dual role, this study evaluated the potential of the microalga Chlorella vulgaris on nutrient removal from a paper industry effluent and bioenergy production. Firstly, experiments were performed to assess the potential of this microalga to: (i) successfully grow in different concentrations of a paper industry effluent (20% to 100%), and (ii) treat the industrial effluent, reducing phosphorus concentrations to values below the accepted legal limits. Then, a techno-economic assessment was performed to study the viability of a C. vulgaris biorefinery targeting the remediation of a paper industry effluent and bioenergy production. The results have shown that C. vulgaris was able to successfully grow and treat the paper industry effluent. Under these conditions, average biomass productivities determined for this microalga ranged between 15.5 &plusmn, 0.5 and 26 &plusmn, 1 mg dry weight (DW) L&minus, 1 d&minus, 1, with maximum biomass concentrations reaching values between 337 &plusmn, 9 and 495 &plusmn, 25 mg DW L&minus, 1. Moreover, final phosphorus concentrations ranged between 0.12 &plusmn, 0.01 and 0.5 &plusmn, 0.3 mg P L&minus, 1, values below the legal limits imposed by the Portuguese Environment Agency on the paper industry. Regarding the proposal of a microalgal biorefinery for the bioremediation of paper industry effluents with bioenergy production, the techno-economic study demonstrated that six of the seven studied scenarios resulted in an economically-viable infrastructure. The highest net present value (15.4 million euros) and lowest discounted payback period (13 years) were determined for Scenario 3, which assumed a photosynthetic efficiency of 3%, a lipids extraction efficiency of 75%, and an anaerobic digestion efficiency of 45%. Therefore, it was possible to conclude that besides being economically viable, the proposed biorefinery presents several environmental benefits: (i) the remediation of an industrial effluent, (ii) CO2 uptake for microalgal growth, which contributes to a reduction in greenhouse gases emissions, (iii) production of clean and renewable energy, (iv) soil regeneration, and (v) promotion of a circular economy.

Cultivation of microalgae has been the focus of several research studies worldwide, due to the huge potential of these photosynthetic microorganisms in a wide range of applications, namely environmental and biotechnological ones. Regarding environmental applications, these microorganisms can play an important role in CO2 uptake and wastewater treatment processes and can be used as raw materials for bioenergy production. However, cultivation of these microorganisms for these applications still faces some problems: (1) it is very difficult to maintain pure cultures of these microorganisms in wastewater treatment processes and (2) bioenergy production process using these microorganisms is still not economically viable. To face these challenges, several studies have reported the use of microalgal consortia. When using microalgal consortia, cooperative interactions can occur, enhancing biomass productivities and therefore nutrients uptake and lipids content. Additionally, these systems tend to be more resistant to environmental conditions’ oscillations, facilitating the overall production process. In this study, an overview on the use of microalgal consortia for CO2 capture, wastewater treatment and bioenergy production is provided, focusing on the interactions that can occur between these microorganisms and how they can improve these environmental applications.

The increased interest in photosynthetic microorganisms for wastewater treatment processes has led to the demand for new biomass harvesting strategies. Biofilm systems have emerged as a good alternative to planktonic photosynthetic cultures. However, knowledge on the environmental aspects influencing microalgal/cyanobacterial biofilm formation is required. This study reports the influence of: (i) surface physicochemical properties of selected microorganisms (Chlorella vulgaris, Pseudokirchneriella subcapitata, Synechocystis salina, and Microcystis aeruginosa) and materials (copper—Cu; glass—G; poly(methyl methacrylate)—PMMA; polystyrene—PS; polyvinyl chloride—PVC; and AISI316 stainless steel—SS) and (ii) culture media composition (glucose-deficient and glucose-enriched media) on biofilm formation (up to 7 days), with constant temperature, light irradiation, and shaking conditions. Adhesion was assessed through thermodynamic prediction of adhesion and by in vitro adhesion assays on microtiter plates. In general, higher biofilm densities were observed after 7 days of experiment, and followed the order: SS > PS > G > PVC > PMMA> Cu. M. aeruginosa was the highest biofilm-former microorganism (2.1 × 106 CFU cm−2), while P. subcapitata has shown lack of ability to adhere. Moreover, the higher biofilm formation ability was observed when glucose-deficient medium was used. Furthermore, the present results pointed out that the thermodynamic approach failed to predict the stochasticity of microalgal/cyanobacterial adhesion. In light of these findings, others factors must be considered when using predictive tools. Therefore, fine-tuning on photosynthetic biofilm formation can be obtained by optimizing the bulk fluid composition and the type of surface. In conclusion, the results show the potential of the selected microalgae/cyanobacteria for biofilm-based technology.

Carbon dioxide (CO2) is an important greenhouse gas (GHG), which concentration in the atmosphere has been rising since the Industrial Revolution due to emissions from anthropogenic activities (mainly burning of fossil fuels). The continuous CO2 emissions may lead to a potentially irreversible climate change (global warming) and ocean acidification. Even if CO2 emissions could be cut to zero today, the environmental impacts would persist in the future due to the long residence time of this GHG. Therefore an international agreement was signed, aiming to limit the increase of the global temperature at 2°C. In this context, CO2 capture from large point sources is gaining the attention of the scientific community as a mitigation option. The pure stream obtained can be transported and stored, avoiding the emission of high amounts of CO2. However, since half of the CO2 emissions come from diffuse sources, capturing CO2 from the atmosphere may be also needed to fulfill the mitigation targets. Despite the higher costs when compared to CO2 capture from large sources, negative emission technologies (NETs) present several advantages: (1) it can capture CO2 emitted from different sources at different locations and time, and (2) the sequestration site can be placed anywhere, avoiding infrastructures’ transportation. NETs can be divided into two routes: (1) direct air capture—using physicochemical processes and (2) indirect air capture—using biological processes. This chapter aims to present an overview of the main NETs, demonstrating their advantages and drawbacks. Currently, there is no single process that can be considered the only solution to achieve the mitigation goals. Research efforts should be made to completely assess the environmental impacts and reduce its costs, possibly through a process integration.

BACKGROUND: We describe a female infant with Fragile-X syndrome, with a fully expanded FMR1 allele and preferential inactivation of the homologous X-chromosome carrying a de novo deletion. This unusual and rare case demonstrates the importance of a detailed genomic approach, the absence of which could be misguiding, and calls for reflection on the current clinical and diagnostic workup for developmental disabilities. CASE PRESENTATION: We present a female infant, referred for genetic testing due to psychomotor developmental delay without specific dysmorphic features or relevant family history. FMR1 mutation screening revealed a methylated full mutation and a normal but inactive FMR1 allele, which led to further investigation. Complete skewing of X-chromosome inactivation towards the paternally-inherited normal-sized FMR1 allele was found. No pathogenic variants were identified in the XIST promoter. Microarray analysis revealed a 439 kb deletion at Xq28, in a region known to be associated with extreme skewing of X-chromosome inactivation. CONCLUSIONS: Overall results enable us to conclude that the developmental delay is the cumulative result of a methylated FMR1 full mutation on the active X-chromosome and the inactivation of the other homologue carrying the de novo 439 kb deletion. Our findings should be taken into consideration in future guidelines for the diagnostic workup on the diagnosis of intellectual disabilities, particularly in female infant cases. Dr. Paula Jorge received a research grant “Bolsa de Investigação DEFI 2015”, CHP, E.P.E. info:eu-repo/semantics/publishedVersion

Congenital muscular dystrophy type 1A (MDC1A) is one of the main subtypes of early-onset muscle disease, caused by disease-associated variants in the laminin-α2 (LAMA2) gene. MDC1A usually presents as a severe neonatal hypotonia and failure to thrive. Muscle weakness compromises normal motor development, leading to the inability to sit unsupported or to walk independently. The phenotype associated with LAMA2 defects has been expanded to include milder and atypical cases, being now collectively known as LAMA2-related muscular dystrophies (LAMA2-MD). Through an international multicenter collaborative effort, 61 new LAMA2 disease-associated variants were identified in 86 patients, representing the largest number of patients and new disease-causing variants in a single report. The collaborative variant collection was supported by the LOVD-powered LAMA2 gene variant database (https://www.LOVD.nl/LAMA2), updated as part of this work. As of December 2017, the database contains 486 unique LAMA2 variants (309 disease-associated), obtained from direct submissions and literature reports. Database content was systematically reviewed and further insights concerning LAMA2-MD are presented. We focus on the impact of missense changes, especially the c.2461A > C (p.Thr821Pro) variant and its association with late-onset LAMA2-MD. Finally, we report diagnostically challenging cases, highlighting the relevance of modern genetic analysis in the characterization of clinically heterogeneous muscle diseases. info:eu-repo/semantics/publishedVersion

Microalgae and cyanobacteria have received ample attention in the last few decades due to their environmental and biotechnological applications. Co-cultures of these microorganisms may present benefits particularly on wastewater bioremediation and biomass production. However, the understanding on the interactions between photosynthetic microorganisms is still in an early stage of knowledge. In this line, the aim of the present study was the evaluation of the growth dynamics of co-cultures of a cyanobacterium, Synechocystis salina, and a microalga, Pseudokirchneriella subcapitata, under low phosphate-phosphorus concentrations. Kinetic growth parameters were determined through the Monod and modified Gompertz models and evidence of allelochemical production was confirmed through metabolomic analysis of the supernatant obtained from the co-cultures using GC-MS and 1D-NMR. Kinetic growth parameters have shown that P. subcapitata was better adapted to grow under low phosphorus concentrations. Co-cultivation of these microorganisms did not influence P. subcapitata growth; however, S. salina growth was strongly inhibited. The modified Gompertz model has shown that growth inhibition of S. salina in co-cultures may be related to the activity of allelochemicals produced by P. subcapitata. This assumption was corroborated by the assessment of the antimicrobial potential of lactic acid (2-hydroxypropanoic acid), an organic acid identified in the supernatant from the co-cultures with growth inhibitory effects against S. salina.

Biofilms can cause severe problems to human health due to the high tolerance to antimicrobials; consequently, biofilm science and technology constitutes an important research field. Growing a relevant biofilm in the laboratory provides insights into the basic understanding of the biofilm life cycle including responses to antibiotic therapies. Therefore, the selection of an appropriate biofilm reactor is a critical decision, necessary to obtain reproducible and reliable in vitro results. A reactor should be chosen based upon the study goals and a balance between the pros and cons associated with its use and operational conditions that are as similar as possible to the clinical setting. However, standardization in biofilm studies is rare. This review will focus on the four reactors (Calgary biofilm device, Center for Disease Control biofilm reactor, drip flow biofilm reactor, and rotating disk reactor) approved by a standard setting organization (ASTM International) for biofilm experiments and how researchers have modified these standardized reactors and associated protocols to improve the study and understanding of medical biofilms.

Background Pathogenic variants in ryanodine receptor type 1 (RYR1) gene are an important cause of congenital myopathy. The clinical, histopathologic and genetic spectrum is wide. Objective Review a group of the patients diagnosed with ryanodinopathy in a tertiary centre from North Portugal, as an attempt to define some phenotypical patterns that may help guiding future diagnosis. Methods Patients were identified from the database of the reference centre for Neuromuscular Disorders in North Portugal. Their data (clinical, histological and genetic) was retrospectively accessed. Results Seventeen RYR1-related patients (including 4 familial cases) were identified. They were divided in groups according to three distinctive clinical characteristics: extraocular muscle (EOM) weakness (N = 6), disproportionate axial muscle weakness (N = 2) and joint laxity (N = 5). The fourth phenotype includes patients with mild tetraparesis and no distinctive clinical features (N = 4). Four different histopathological patterns were found: centronuclear (N = 5), central core (N = 4), type 1 fibres predominance (N = 4) and congenital fibre type disproportion (N = 1) myopathies. Each index case, except two patients, had a different RYR1 variant. Four new genetic variants were identified. All centronuclear myopathies were associated with autosomal recessive inheritance and EOM weakness. All central core myopathies were caused by pathogenic variants in hotspot 3 with autosomal dominant inheritance. Three genetic variants were reported to be associated to malignant hyperthermia susceptibility. Conclusions Distinctive clinical features were recognized as diagnostically relevant: extraocular muscle weakness (and centronuclear pattern on muscle biopsy), severe axial weakness disproportionate to the ambulatory state and mild tetraparesis associated with (proximal) joint laxity. There was a striking genetic heterogeneity, including four new RYR1 variants.

Microalgal based biofuels have been reported as an attractive alternative for fossil fuels, since they constitute a renewable energy source that reduces greenhouse gas emissions to the atmosphere. However, producing biofuels from microalgae is still not economically viable. Therefore, the integration of biofuel production with other microalgal applications, such as CO2 capture and nutrient removal from wastewaters, would reduce the microalgal production costs (and the environmental impact of cultures), increasing the economic viability of the whole process. Additionally, producing biofuels from microalgae strongly depends on microalgal strain and culture conditions. This study evaluates the effect of culture conditions, namely light irradiance (36, 60, 120 and 180 μE m−2 s−1) and light:dark ratio (10:14, 14:10 and 24:0), on microalgal growth, atmospheric CO2 uptake and nutrient (nitrogen and phosphorous) removal from culture medium. Four different microalgal strains, Chlorella vulgaris, Pseudokirchneriella subcapitata, Synechocystis salina and Microcystis aeruginosa, were studied to ascertain the most advantageous regarding the referred applications. This study has shown that higher light irradiance values and light periods resulted in higher specific growth rates and CO2 uptake rates. C. vulgaris presented the highest specific growth rate and CO2 uptake rate: 1.190 ± 0.041 d−1 and 0.471 ± 0.047 gCO2 L−1 d−1, respectively. All the strains have shown high nitrogen removal efficiencies, reaching 100% removal percentages in cultures with higher light supply. Phosphorus removal increased with light irradiance and with light:dark ratio. The highest removal efficiency, 67.6 ± 7.1%, was achieved by the microalga C. vulgaris.

The development of anthropogenic activities has led to an excessive disposal of wastes into water bodies, thus reducing water quality and damaging aquatic ecosystems. To avoid the negative impacts associated to the discharge of wastes into water courses, effective remediation processes are required to reduce nitrogen and phosphorus concentrations in discharged effluents. Current methodologies applied for nutrients removal tend to be complex, expensive and energy demanding. Therefore, cultivation of microalgae has appeared as an emerging alternative for nutrients removal from wastewaters. These photosynthetic microorganisms require large amounts of nitrogen and phosphorus for their growth. However, since it is very difficult to maintain pure cultures of these microorganisms in wastewater treatment processes, several studies have reported the use of natural and artificial microalgal consortia composed exclusively by microalgae or by microalgae and bacteria. The use of these consortia in the remediation of wastewaters can be very advantageous because: (i) cooperative interactions between the co-cultivated microorganisms can occur, enhancing the overall uptake of nutrients; and (ii) these systems tend to be more resistant to environmental conditions oscillations. This study provides an updated review of the literature regarding the application of microalgal consortia in the remediation of wastewaters from different sources, focusing on the mechanisms involved in nutrients removal by microalgae and the main interactions established between the microorganisms integrating the consortia and how they can influence nutrients removal efficiencies. (c) 2016 Elsevier B.V.

Algae presents a viable biofuel alternative because the production of algae for fuel, unlike other agro-based biofuels, does not compete with food production. This book covers algae-based biofuel options and discusses the design and economic viability of algal bioenergy co-production concepts.

The extensive use of fossil fuels has contributed to the scarcity of this energy source and to an increase of greenhouse gases emissions to the atmosphere contributing to the global warming phenomenon. To avoid the problems associated to fossil fuels, it becomes necessary to use cleaner and renewable energy sources. However, these new energy sources should compete with the prices of fossil fuels. In the last decades, several efforts have been conducted to produce chemical compounds that can replace fossil fuels using microorganisms. For that, these compounds, normally corresponding to higher alcohols or long-chain fatty acids, must have properties comparable to those of current transportation fuels. However, native organisms cannot synthesize these fuels in a cost-effective way. Owing to that, advances in metabolic engineering, as well as in synthetic and systems biology, appear as a viable alternative for the production of these compounds. Higher alcohols, such as 1-butanol, isobutanol, 2-methyl-1-butanol and 3-methyl-1-butanol, have shown to present comparable properties to those of gasoline, being potential substitutes or additives for this petroleum-derived fuel. This review shows the recent developments in metabolic engineering of Escherichia coli for higher alcohols production and tolerance, emphasizing two different pathways: (i) the fermentative pathway, originally from microorganisms from the genera Clostridia ; and (ii) the non-fermentative pathway, also known as the keto acid pathway. Engineering these synthetic pathways in heterologous organisms that are well-known and better suited for large-scale growth and industrial production, normally E. coli and Saccharomyces cerevisiae , can significantly improve advanced biofuels production.

Landfill leachates result from the degradation of solid residues in sanitary landfills, thus presenting a high variability in terms of composition. Normally, these effluents are characterized by high ammoniacal-nitrogen (N–NH4+) concentrations, high chemical oxygen demands and low phosphorus concentrations. The development of effective treatment strategies becomes difficult, posing a serious problem to the environment. Phycoremediation appears to be a suitable alternative for the treatment of landfill leachates. In this study, the potential of Chlorella vulgaris for biomass production and nutrients (mainly nitrogen and phosphorus) removal from different compositions of a landfill leachate was evaluated. Since microalgae also require phosphorus for their growth, different loads of this nutrient were evaluated, giving the following N:P ratios: 12:1, 23:1 and 35:1. The results have shown that C. vulgaris was able to grow in the different leachate compositions assessed. However, microalgal growth was higher in the cultures presenting the lowest N–NH4+ concentration. In terms of nutrients uptake, an effective removal of N–NH4+ and phosphorus was observed in all the experiments, especially in those supplied with phosphorus. Nevertheless, N–NO3− removal was considered almost negligible. These promising results constitute important findings in the development of a bioremediation technology for the treatment of landfill leachates.