Author Correction: Forearc carbon sink reduces long-term volatile recycling into the mantle.

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

Author Correction: Forearc carbon sink reduces long-term volatile recycling into the mantle.

Change history: In this Article, the original affiliation 2 was not applicable and has been removed. In addition, in the Acknowledgements there was a statement missing and an error in a name. These errors have been corrected online.

Forearc carbon sink reduces long-term volatile recycling into the mantle.

Carbon and other volatiles in the form of gases, fluids or mineral phases are transported from Earth's surface into the mantle at convergent margins, where the oceanic crust subducts beneath the continental crust. The efficiency of this transfer has profound implications for the nature and scale of geochemical heterogeneities in Earth's deep mantle and shallow crustal reservoirs, as well as Earth's oxidation state. However, the proportions of volatiles released from the forearc and backarc are not well constrained compared to fluxes from the volcanic arc front. Here we use helium and carbon isotope data from deeply sourced springs along two cross-arc transects to show that about 91 per cent of carbon released from the slab and mantle beneath the Costa Rican forearc is sequestered within the crust by calcite deposition. Around an additional three per cent is incorporated into the biomass through microbial chemolithoautotrophy, whereby microbes assimilate inorganic carbon into biomass. We estimate that between 1.2 × 108 and 1.3 × 1010 moles of carbon dioxide per year are released from the slab beneath the forearc, and thus up to about 19 per cent less carbon is being transferred into Earth's deep mantle than previously estimated.

Consensus protocol for management of early and late twin-twin transfusion syndrome: Delphi study.

OBJECTIVE: Fetoscopic laser photocoagulation (FLP) is a well-established treatment for twin-twin transfusion syndrome (TTTS) between 16 and 26 weeks' gestation. High-quality evidence and guidelines regarding the optimal clinical management of very early (prior to 16 weeks), early (between 16 and 18 weeks) and late (after 26 weeks) TTTS are lacking. The aim of this study was to construct a structured expert-based clinical consensus for the management of early and late TTTS. METHODS: A Delphi procedure was conducted among an international panel of experts. Participants were chosen based on their clinical expertise, affiliation and relevant publications. A four-round Delphi survey was conducted using an online platform and responses were collected anonymously. In the first round, a core group of experts was asked to answer open-ended questions regarding the indications, timing and modes of treatment for early and late TTTS. In the second and third rounds, participants were asked to grade each statement on a Likert scale (1, completely disagree; 5, completely agree) and to add any suggestions or modifications. At the end of each round, the median score for each statement was calculated. Statements with a median grade of 5 without suggestions for change were accepted as the consensus. Statements with a median grade of 3 or less were excluded from the Delphi process. Statements with a median grade of 4 were modified according to suggestions and reconsidered in the next round. In the last round, participants were asked to agree or disagree with the statements, and those with more than 70% agreement without suggestions for change were considered the consensus. RESULTS: A total of 122 experts met the inclusion criteria and were invited to participate, of whom 53 (43.4%) agreed to take part in the study. Of those, 75.5% completed all four rounds. A consensus on the optimal management of early and late TTTS was obtained. FLP can be offered as early as 15 weeks' gestation for selected cases, and can be considered up to 28 weeks. Between 16 and 18 weeks, management should be tailored according to Doppler findings. CONCLUSIONS: A consensus-based treatment protocol for early and late TTTS was agreed upon by a panel of experts. This protocol should be modified at the discretion of the operator, according to their experience and the specific demands of each case. This should advance the quality of future studies, guide clinical practice and improve patient care. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Impact of Asthma Inhalers on Global Climate: A Systematic Review of Their Carbon Footprint and Clinical Outcomes in Spain.

BACKGROUND: Pressurized metered-dose inhalers (pMDIs) exert an environmental impact resulting from CO2 emissions. Therapeutic alternatives with less environmental impact are widely used. Nevertheless, the choice of device and appropriate therapy should meet the clinical needs and the characteristics of the patient. OBJECTIVE: The primary objective was to estimate the impact of pMDIs prescribed for any indication on annual CO2 emissions in Spain.The secondary objective was to evaluate the potential impact of switching pMDIs to dry-powder inhalers (DPIs) in patients with asthma. METHODS: A systematic review of the evidence published during 2010-2021 was carried out. Average annual CO2 emissions of DPIs and pMDIs were calculated in 2 scenarios: the current situation and a hypothetical situation involving a switch from all pMDIs to DPIs. The impact of the switch on clinical outcomes was also evaluated. RESULTS: The total value of CO2-eq/year due to DPIs and pMDIs accounted for 0.0056% and 0.0909%, respectively, of total emissions in Spain. In the event of switching pMDIs to DPIs, except those used for rescue medication, the percentages were 0.0076% and 0.0579%. The evaluation of efficacy, handling, satisfaction, safety, and use of health care resources was not conclusive. CONCLUSIONS: Current CO2 emissions by pMDIs account for a small percentage of the total CO2 footprint in Spain. Nevertheless, there is a need for research into new and more sustainable devices. Suitability and patient clinical criteria such as age and inspiratory flow should be prioritized when prescribing an inhaler.

Milk triglycerides from dairy cows abomasally infused with increasing amounts of high-oleic sunflower fatty acids.

The triglyceride composition of milk fat largely determines the manufacturing characteristics of products containing milk fat. Increasing oleic acid content of milk fat might be desirable for human nutrition and also for butter and whipping cream, among other product applications. The objective of this research was to determine the effects of increasing intestinally available oleic acid (provided via abomasal infusion) on the profile of milk triglycerides. A control and 4 increasing doses of free fatty acids from high oleic sunflower oil (HOSFA) were infused into the abomasum of 4 lactating dairy cows in a changeover experimental design with periods of 7 d. Treatments were (1) control (no fatty acids infused), (2) HOSFA (250 g/d), (3) HOSFA (500 g/d), (4) HOSFA (750 g/d), and (5) HOSFA (1,000 g/d). All treatments included meat solubles and Tween 80 as emulsifiers. Infusion of HOSFA increased oleic acid and decreased short- and medium-chain fatty acids in milk fat. Statistical analysis of results showed linear changes in most of the milk triglycerides analyzed. The most significant changes as the result of increasing HOSFA infusion were a decrease in triglycerides with saturated fatty acids (butyrin-caprylin-palmitin, butyrin-laurin-olein, butyrin-myristin-palmitin, butyrin-palmitin-palmitin, caproin-myristin-palmitin, butyrin-palmitin-stearin, caproin-palmitin-palmitin) and an increase in dioleyl triglycerides (with butyric, lauric, myristic and palmitic acids) and triolein. The synthesis of triglyceride is position-specific and does not follow a random distribution model.

Functional properties of cream from dairy cows with experimentally altered milk fat composition.

Modification of milk fat composition might be a desirable method to alter manufacturing characteristics or produce dairy products low in saturated fat that more closely meet consumer dietary preferences. The aim of this research was to evaluate functional properties of cream obtained from milks with fat composition modified by altering the profile of long-chain fatty acids (FA) absorbed from the intestine. A control and 5 mixtures of long-chain free FA were infused into the abomasum of lactating dairy cows in a 6 × 6 Latin square design with 21-d periods. Treatments were as follows: (1) control (no FA infused), (2) mostly saturated FA (C16:C18 = 0.74), (3) low linoleic palm FA (C16:C18 = 0.73), (4) palm FA (C16:C18 = 0.73), (5) soy FA (C16:C18 = 0.10), and (6) high palmitic soy FA (C16:C18 = 0.73). All treatments included meat solubles and Tween 80 as emulsifiers. Viscosity, overrun, whipping time, foam firmness, and foam stability were evaluated in creams (33% fat). Cream from cows infused with soy FA (treatment 5) had the longest whipping time and lowest overrun, foam stability, viscosity, melting point, firmness, and solid fat content at 5 and 20°C because the fat had the highest unsaturated FA content. Increasing palmitic acid content of soy FA (treatment 6) improved functional variables in cream relative to soy FA alone. Differences among treatments 1 to 4 were less pronounced because of the effect of C18:1 trans in treatments 3 and 4 on milk fat yield and composition. Milk fat from cows infused with palm FA (treatment 4) exhibited comparable or better functionality than control cream. Increased polyunsaturated FA in milk fat resulted in increased amounts of triglyceride (TG) fractions with 28, 30, 38, and 40 carbon numbers, increased oleic acid resulted in increased 50-carbon TG, and higher palmitic and myristic acids resulted in greater 44, 46, and 48 carbon number TG. These TG groups consistently correlated with functional properties of creams from different treatments. Our results indicated that optimal functionality of cream is dependent more on its content of palmitic acid than on unsaturated FA. However, an optimal composition of milk fat for cream functional characteristics might be obtained through nutritional manipulation of diets for dairy cows to deliver an optimal profile of FA.

Etest ECVs/ECOFFs for Detection of Resistance in Prevalent and Three Nonprevalent Candida spp. to Triazoles and Amphotericin B and Aspergillus spp. to Caspofungin: Further Assessment of Modal Variability.

Susceptibility testing is an important tool in the clinical setting; its utility is based on the availability of categorical endpoints, breakpoints (BPs), or epidemiological cutoff values (ECVs/ECOFFs). CLSI and EUCAST have developed antifungal susceptibility testing, BPs, and ECVs for some fungal species. Although the concentration gradient strip bioMérieux Etest is useful for routine testing in the clinical laboratory, ECVs are not available for all agent/species; the lack of clinical data precludes development of BPs. We reevaluated and consolidated Etest data points from three previous studies and included new data. We defined ECOFFinder Etest ECVs for three sets of species-agent combinations: fluconazole, posaconazole, and voriconazole and 9 Candida spp.; amphotericin B and 3 nonprevalent Candida spp.; and caspofungin and 4 Aspergillus spp. The total of Etest MICs from 23 laboratories (Europe, the Americas, and South Africa) included (antifungal agent dependent): 17,242 Candida albicans, 244 C. dubliniensis, 5,129 C. glabrata species complex (SC), 275 C. guilliermondii (Meyerozyma guilliermondii), 1,133 C. krusei (Pichia kudriavzevii), 933 C. kefyr (Kluyveromyces marxianus), 519 C. lusitaniae (Clavispora lusitaniae), 2,947 C. parapsilosis SC, 2,214 C. tropicalis, 3,212 Aspergillus fumigatus, 232 A. flavus, 181 A. niger, and 267 A. terreus SC isolates. Triazole MICs for 66 confirmed non-wild-type (non-WT) Candida isolates were available (ERG11 point mutations). Distributions fulfilling CLSI ECV criteria were pooled, and ECOFFinder Etest ECVs were established for triazoles (9 Candida spp.), amphotericin B (3 less-prevalent Candida spp.), and caspofungin (4 Aspergillus spp.). Etest fluconazole ECVs could be good detectors of Candida non-WT isolates (59/61 non-WT, 4 of 6 species).

Clinical and molecular characterization of Chilean patients with X-linked hypophosphatemia.

We report the most comprehensive clinical and molecular characterization of XLH patients performed in Chile. We show high prevalence of musculoskeletal burden and pain, associated with significantly impaired physical capacity and quality of life, with many relevant complications presenting more frequently than previously reported in cohorts from developed countries. INTRODUCTION: Our current understanding of the clinical presentation and natural history of X-linked hypophosphatemia (XLH) comes mainly from cohorts from developed countries, with limited data on the clinical and genetic abnormalities of XLH patients in South America. OBJECTIVE: To describe the clinical, biochemical, and molecular presentation of patients with XLH in Chile. METHODS: Patients with XLH referred by endocrinologist throughout Chile were included. Demographic data and clinical presentation were obtained from a clinical interview. Surveys were applied for quality of life (QoL), pain, and functionality. FGF23 was measured by ELISA, and genetic testing was performed. Imaging studies were conducted to assess skeletal and renal involvement. RESULTS: We included 26 patients, aged 2-64 years, from 17 unrelated Chilean families. All pediatric patients but only 40% of adults were receiving conventional therapy, while 65% of all patients had elevated alkaline phosphatase. All patients had mutations in PHEX, including 5 novel variants. Radiographic skeletal events (RSE) and enthesopathies in adults were frequent (34% and 85%, respectively). The duration of treatment was associated with fewer RSE (p < 0.05). Most adults reported pain and impaired QoL, and 50% had impaired physical capacity. The number of enthesopathies was associated with worse pain and stiffness scores (p < 0.05). CONCLUSION: Chilean patients with XLH have a high prevalence of musculoskeletal burden associated with pain and impaired physical capacity and QoL, especially in adults who were generally undertreated. These data identify a significant unmet need, inform our understanding of the current status of patients, and can guide care for XLH patients in similarly socioeconomically defined countries.

Long-term decline of the Amazon carbon sink.

Atmospheric carbon dioxide records indicate that the land surface has acted as a strong global carbon sink over recent decades, with a substantial fraction of this sink probably located in the tropics, particularly in the Amazon. Nevertheless, it is unclear how the terrestrial carbon sink will evolve as climate and atmospheric composition continue to change. Here we analyse the historical evolution of the biomass dynamics of the Amazon rainforest over three decades using a distributed network of 321 plots. While this analysis confirms that Amazon forests have acted as a long-term net biomass sink, we find a long-term decreasing trend of carbon accumulation. Rates of net increase in above-ground biomass declined by one-third during the past decade compared to the 1990s. This is a consequence of growth rate increases levelling off recently, while biomass mortality persistently increased throughout, leading to a shortening of carbon residence times. Potential drivers for the mortality increase include greater climate variability, and feedbacks of faster growth on mortality, resulting in shortened tree longevity. The observed decline of the Amazon sink diverges markedly from the recent increase in terrestrial carbon uptake at the global scale, and is contrary to expectations based on models.

Rathke's cleft cyst infections and pituitary abscesses: case series and review of the literature.

PURPOSE: Pituitary abscesses (PAs) are a rare clinical entity which may arise from normal pituitary tissue or underlying lesions within the gland. Rathke's cleft cysts (RCCs) are not commonly associated with the development of PA. METHODS: Retrospective chart review of three patients with PAs within RCCs at a single university center and review of the literature. RESULTS: Three cases are reported. The first case presented with fever and headache and a history of prior surgery due to RCC and a recent respiratory tract infection. The second case had a history of recent skin infections and presented with sudden onset headache and hypopituitarism. In the third case, chronic visual field impairment prompted an ophthalmologic evaluation resulting in a diagnosis of an adenoma and an infected RCC. In all three cases, an endoscopic endonasal approach was performed to drain infected tissue and allowed microbiological identification of gram-positive cocci, followed by treatment with antibiotics for at least three weeks. Cases in the literature are scarce and the diagnosis is usually made intraoperatively due to non-specific manifestations and imaging. PAs arising from underlying pituitary lesions are less common than primary PAs. Differential diagnosis should include pituitary apoplexy, hypophysitis and other cystic lesions. CONCLUSION: PAs occurring in RCCs are infrequent. Clinical manifestations are commonly subacute, without septic symptoms. Imaging is usually non-specific. Preoperative diagnosis is infrequent and a broad differential diagnosis should be considered. Empirical antimicrobial therapy should be initiated and adjusted after obtaining cultures to reduce the rate of recurrence and improve clinical outcomes.

Concordance between estimated glomerular filtration rate using equations and that measured using an imaging method.

BACKGROUND: Guidelines recommend estimating glomerular filtration rate (GFR) using creatinine-based equations (CBE). AIM: To evaluate the agreement between GFR measured using radionuclide imaging and estimated using creatinine-based equations. MATERIAL AND METHODS: In 421 patients aged 54 ± 17 years (47% women) GFR was estimated using the MDRD-4, CKD-EPI and the body surface adjusted Cockroft Gault equation. GFR was also measured using a radionuclide imaging method with 99mTc-DTPA. The concordance between estimated and measured GFR was calculated using Lin's concordance coefficient and Bland and Altman plots. RESULTS: Average GFR values obtained with CKD-EPI, MDRD-4, body surface adjusted Cockroft Gault equation and 99mTc-DTPA imaging were 75.9 ± 26.6, 76.3 ± 28.8, 77.1 ± 31.6 and 77.9 ± 28.4 ml/min/1.73 m2, respectively. There was no significant difference in means and 29% of participants had a GFR < 60 ml/min/1.73 m2 by CKD-EPI. The correlation was good between equations, but acceptable when compared with the 99mTc-DTPA imaging. The weighted kappa between CBEs was good, but low when comparing CBEs with measured GFR. The Lin's concordance coefficient between estimated and measured GFR was low. CONCLUSIONS: GFR measured by 99mTc-DTPA radionuclide imaging has a low correlation and poor concordance with estimations using CBE.

Antiphospholipid Syndrome: A Seronegative Case at Ho Teaching Hospital, Ghana.

Antiphospholipid syndrome is a systemic autoimmune disease characterized by thrombosis and/or pregnancy morbidity in the presence of persistently positive antiphospholipid antibodies. The finding of individuals who present a clinical picture highly suggestive of antiphospholipid syndrome, but who are persistently negative for "criteria" of antiphospholipid antibodies has led physicians to refer to this patient population as having "seronegative" Antiphospholipid syndrome. We present a case of a 35-years old patient with strong clinical suspicion of antiphospholipid syndrome, with a history of recurrent pregnancy loss and one episode of deep vein thrombosis, but serologically negative, who was admitted and successfully managed and discharged.

Le syndrome des antiphospholipides est une maladie autoimmune systémique caractérisée par une thrombose et/ou une morbidité de la grossesse en présence d'anticorps antiphospholipides positifs persistants. La découverte d'individus qui présentent un tableau clinique hautement évocateur du syndrome des antiphospholipides, mais qui sont constamment négatifs pour les « critères ¼ des anticorps antiphospholipides a conduit les médecins à qualifier cette population de patients de syndrome des antiphospholipides « séronégatifs ¼. Nous présentons le cas d'une patiente de 35 ans avec une forte suspicion clinique de syndrome des antiphospholipides, avec des antécédents de fausses couches à répétition et un épisode de thrombose veineuse profonde, mais sérologiquement négative, qui a été admise et prise en charge avec succès et sortie de l'hôpital.

Pseudomonas aeruginosa isolates from cystic fibrosis patients induce neutrophil extracellular traps with different morphologies that could correlate with their disease severity.

Cystic fibrosis (CF) is a disease characterized by bacterial chronic infection of the respiratory tract and inflammation, which leads to a progressive decrease in lung function. Pseudomonas aeruginosa is commonly isolated from the sputum of patients and their presence is associated with a predominant airway inflammation with neutrophils, causing chronic colonization and higher mortality rates. Neutrophil extracellular traps (NETs) have been observed in response against Pseudomonas, however, these cannot eliminate the pathogen from the respiratory tract, so one possibility is that the bacteria could promote their production to use them as a scaffold to colonize the lungs and as a nutrient source, however, their overproduction could also lead to increased damage to the lungs. In this work, we evaluated NETs formation by Pseudomonas clinical isolates obtained from CF patients and found that these induced NETs formation with globular or spread morphologies, of note, we found that there is a trend by which the spread forms were induced mainly by isolates obtained from patients with severe disease, whereas, the globular morphologies were observed for isolates obtained from patients with mild/moderate disease. Finally, we screened for bacterial molecules implicated in NETs formation and found that Exotoxin S, pyocin S2 and pyoverdine could participate in the process.

Psychosocial repercussion of migraine: is it a stigmatized disease?

INTRODUCTION: Stigma manifests both in prejudices and rejection from society towards patients who suffer from a specific pathology, and by patient's internalization of this discrimination, with the consequent repercussions on their state of mind and quality of life. The aim of the study was to quantify the stigma associated with migraine and analyze whether it is related to the clinical-demographic characteristics of the patients, as well as the possible impact on their daily lives. MATERIALS AND METHODS: The stigma scale for chronic illness (SSCI) and other questionnaires were administered to 56 patients with episodic migraine (EM), 18 with chronic migraine (CM), and 21 with epilepsy, as a control group. RESULTS: The mean SSCI score was higher (51.6 ± 15.0) in the CM group than in the EM (45.0 ± 13.5) and epilepsy (47.6 ± 15.5) groups, without reaching statistical significance. In addition, the score was higher in patients who were unemployed, divorced, and in those who had migraine with aura. A statistically significant correlation was found between the SSCI score and the impact of migraine on daily life, the presence of stress, anxiety and depression, and low self-esteem. CONCLUSIONS: There is a stigma around migraine in our society, which seems to be more prevalent in patients with certain socio-demographic characteristics, and that is related to stress, mood alterations, and low self-esteem. Trying to reduce stigma could contribute to improve the control of migraine and reduce the impact of the disease at a socio-economic level.

Virulence properties and antimicrobial resistance of Pseudomonas aeruginosa isolated from cave waters at Roraima Tepui, Guayana Highlands.

Pseudomonas aeruginosa is a prominent member of emerging waterborne pathogens. The environmental reservoirs of multi-resistant phenotypes and other virulence factors in this bacterium are poorly understood. Our study aimed to determine the virulence properties of P. aeruginosa isolated from Roraima Sur Cave (RSC) waters at Guayana Highlands. Based on the best identification at species level by biochemical tests, 16S rRNA sequencing and phylogenetic inferences, one RSC isolate named LG11 was characterized for virulence properties in comparison with P. aeruginosa reference strains. PCR amplification of alginate, elastase, exoenzyme S, exotoxin A, neuraminidase and Quorum-Sensing genes showed a high virulence potential in LG11. This isolate demonstrated multi-resistance to ceftriaxone, tigecycline and imipenem. Pyocyanin production was greater in LG11 (0·478 µg ml-1 ) than the strain ATCC 10145 (0·316 µg ml-1 ), but the highest pigment concentration (2·140 µg ml-1 ) was displayed by the clinical strain CVCM 937 (P = 0·000175). Pronounced biomass production on granite and glass (P < 0·05) and well-developed biofilms indicated the ability of P. aeruginosa from RSC to colonize surfaces found in human and healthcare environments. These data suggest that waters from pristine ecosystems such as RSC could be reservoirs of this opportunistic bacterium carrying important virulence properties with potential epidemiological implications. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows for the first time the occurrence of virulence genes and multi-resistance to antimicrobials in Pseudomonas aeruginosa isolated from cave waters at Guayana Highlands. These findings, together with the biofilm formation on surfaces found in human and healthcare settings, suggest public health risks and the potential of these virulence properties to be transferred from or to native populations in waters. Our results provide important insights to the current knowledge of P. aeruginosa in the environment, setting the basis for future studies driven to assess reservoirs of multi-resistant bacteria and virulence features unknown in pristine ecosystems.

Method-Dependent Epidemiological Cutoff Values for Detection of Triazole Resistance in Candida and Aspergillus Species for the Sensititre YeastOne Colorimetric Broth and Etest Agar Diffusion Methods.

Although the Sensititre Yeast-One (SYO) and Etest methods are widely utilized, interpretive criteria are not available for triazole susceptibility testing of Candida or Aspergillus species. We collected fluconazole, itraconazole, posaconazole, and voriconazole SYO and Etest MICs from 39 laboratories representing all continents for (method/agent-dependent) 11,171 Candida albicans, 215 C. dubliniensis, 4,418 C. glabrata species complex, 157 C.guilliermondii (Meyerozyma guilliermondii), 676 C. krusei (Pichia kudriavzevii), 298 C.lusitaniae (Clavispora lusitaniae), 911 C.parapsilosissensu stricto, 3,691 C.parapsilosis species complex, 36 C.metapsilosis, 110 C.orthopsilosis, 1,854 C.tropicalis, 244 Saccharomyces cerevisiae, 1,409 Aspergillus fumigatus, 389 A.flavus, 130 A.nidulans, 233 A.niger, and 302 A.terreus complex isolates. SYO/Etest MICs for 282 confirmed non-wild-type (non-WT) isolates were included: ERG11 (C. albicans), ERG11 and MRR1 (C. parapsilosis), cyp51A (A. fumigatus), and CDR2 and CDR1 overexpression (C. albicans and C. glabrata, respectively). Interlaboratory modal agreement was superior by SYO for yeast species and by the Etest for Aspergillus spp. Distributions fulfilling CLSI criteria for epidemiological cutoff value (ECV) definition were pooled, and we proposed SYO ECVs for S. cerevisiae and 9 yeast and 3 Aspergillus species and Etest ECVs for 5 yeast and 4 Aspergillus species. The posaconazole SYO ECV of 0.06 µg/ml for C. albicans and the Etest itraconazole ECV of 2 µg/ml for A. fumigatus were the best predictors of non-WT isolates. These findings support the need for method-dependent ECVs, as, overall, the SYO appears to perform better for susceptibility testing of yeast species and the Etest appears to perform better for susceptibility testing of Aspergillus spp. Further evaluations should be conducted with more Candida mutants.

Norovirus and human adenovirus occurrence and diversity in recreational water in a karst aquifer in the Yucatan Peninsula, Mexico.

AIMS: To determine the seasonal occurrence and diversity of norovirus (NoV) and human adenovirus (HAdV) in groundwater from sinkholes, and brackish water used for recreational activities in the karst aquifer of the Yucatan Peninsula, Mexico. METHODS AND RESULTS: Hollow fibre ultrafiltration was used to concentrate viruses and standard plaque assay methods were used to enumerate somatic and F+ specific coliphages as viral indicators. Real-time quantitative polymerase chain reaction assays were used to estimate the number of genome copies for NoV strains GI, and GII, and HAdVs. The predominant NoV genotypes and HAdV serotypes were identified by comparative sequence analysis. Somatic and male F+ specific coliphages were detected at concentrations up to 94 and 60 plaque-forming units per 100 ml respectively. The NoV genogroup I (GI) was associated with 50% of the sampled sites during the rainy season only, at concentrations ranging from 120 to 1600 genome copies per litre (GC l-1 ). The NoV genogroup II (GII) was detected in 30 and 40% of the sampled sites during the rainy and dry seasons, respectively, at concentrations ranging from 10 to 290 GC l-1 . During the rainy and dry seasons, HAdVs were detected in 20% of the sites, at concentrations ranging from 24 to 690 GC l-1 . Identification of viral types revealed the presence of NoV GI.2, GII.Pe, GII.P16 and GII.P17, and HAdV F serotypes 40 and 41. CONCLUSIONS: These findings demonstrate that NoVs and HAdVs are prevalent as virus contaminants in the karst aquifer, representing potential health risks particularly during the rainy season, in one of the most important areas used for tourism in Mexico. SIGNIFICANCE AND IMPACT OF THE STUDY: This is one of the few studies conducted in karst aquifers that provide a foundational baseline of the distribution, concentrations and diversity of NoVs and HadVs in these particular environments.

Improved conidiation from entomopathogenic fungi through 26% oxygen pulses in solid-state culture depends on a balance between headspace volume and substrate amounts.

Oxygen-enriched atmospheres applied as periodic pulses increased conidia production from entomopathogenic fungi in agar surface cultures. However, this advantage has not been obtained in solid-state cultures (SSC), probably as a result of different biomass production between both culture systems. In this work, the biomass formation from two Isaria strains was limited in SSC using 5, 2·5 and 1 initial grams of substrate (gds). In the system with 5 gds, conidia production decreased in 26% oxygen-enriched pulses compared to the normal atmosphere. Conversely, 26% oxygen pulses increased conidiation up to one order magnitude in systems with 2·5 and 1 gds, respective to the normal atmosphere. These results were explained by oxygen depletion and high CO2 accumulation in the 5 gds system. Whereas in systems with 2·5 or 1 gds, oxygen levels remained high enough to stimulate conidiation. These results were attributed to the headspace volume:gds ratio, which is suggested to be ≥48 ml per gds. This ratio is proposed as a scaling-up criterion for bioreactor design when oxygen-enriched pulses are used in SSC for improvement of conidia production. SIGNIFICANCE AND IMPACT OF THE STUDY: Oxygen-enriched atmospheres applied as periodic pulses increase conidiation in entomopathogenic fungi (EF). However, this remained restricted to agar surface cultures, since conidiation decreased when carried out in solid-state culture (SSC) which is used as large-scale production system. We identified that in SSC the ratio between the headspace volume containing 26% oxygen-enriched pulses and the grams of substrate determines the conidiation response to oxygen-enriched pulses. For the first time, oxygen-enriched pulses increased conidiation in SSC respective to the normal atmosphere in four EF. This ratio is proposed as a bioreactor criterion design for large-scale conidia production of EF using oxygen-enriched pulses.

HAADF-STEM Image Resolution Enhancement Using High-Quality Image Reconstruction Techniques: Case of the Fe3O4(111) Surface.

From simple averaging to more sophisticated registration and restoration strategies, such as super-resolution (SR), there exist different computational techniques that use a series of images of the same object to generate enhanced images where noise and other distortions have been reduced. In this work, we provide qualitative and quantitative measurements of this enhancement for high-angle annular dark-field scanning transmission electron microscopy imaging. These images are compared in two ways, qualitatively through visual inspection in real and reciprocal space, and quantitatively, through the calculation of objective measurements, such as signal-to-noise ratio and atom column roundness. Results show that these techniques improve the quality of the images. In this paper, we use an SR methodology that allows us to take advantage of the information present in the image frames and to reliably facilitate the analysis of more difficult regions of interest in experimental images, such as surfaces and interfaces. By acquiring a series of cross-sectional experimental images of magnetite (Fe3O4) thin films (111), we have generated interpolated images using averaging and SR, and reconstructed the atomic structure of the very top surface layer that consists of a full monolayer of Fe, with topmost Fe atoms in tetrahedrally coordinated sites.