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Introduction: Causes of epileptic seizures are often multifactorial but for an effective therapy, they should be uncovered in detail. Case Presentation: We present a 67-year-old male patient with a central diabetes insipidus, who experienced a generalized tonic-clonic seizure. The patient was treated with levetiracetam for prevention of further seizures, opioids and non-steroidal anti-inflammatory drugs, i.e., ibuprofen because of severe back pain due to vertebral compression fractures. In this setting, he developed significant hyponatremia and experienced another epileptic seizure. After stopping analgesics and switching from levetiracetam to lacosamide, sodium levels returned to normal and the patient remained free of seizures since then. Conclusion: The interrelationships of medical therapy, sodium levels and epileptic seizures in the context of central diabetes insipidus are discussed.

Introduction: Biocatalysis, particularly through engineered enzymes, presents a cost-effective, efficient, and eco-friendly approach to compound synthesis. We sought to identify ketoreductases capable of synthesizing optically pure alcohols or ketones, essential chiral building blocks for active pharmaceutical ingredients.Methods: Using BioMatchMaker®, an in silico high-throughput platform that allows the identification of wild-type enzyme sequences for a desired chemical transformation, we identified a bacterial SDR ketoreductase from Thermus caliditerrae, Tcalid SDR, that demonstrates favorable reaction efficiency and desired enantiomeric excess.Results: Here we present two crystal structures of the Tcalid SDR in an apo-form at 1.9 Å and NADP-complexed form at 1.7 Å resolution (9FE6 and 9FEB, respectively). This enzyme forms a homotetramer with each subunit containing an N-terminal Rossmann-fold domain. We use computational analysis combined with site-directed mutagenesis and enzymatic characterization to define the substrate-binding pocket. Furthermore, the enzyme retained favorable reactivity and selectivity after incubation at elevated temperature.Conclusion: The enantioselectivity combined with the thermostability of Tcalid SDR makes this enzyme an attractive engineering starting point for biocatalysis applications.

Abstract This study was performed to evaluate the efficacy of Alfamurom (alpha-cypermethrin) against Aedes aegypti mosquitoes under spatial application using a portable ultra-low volume (ULV) nebulizer. The study consisted of two treatments: the treatment with four repetitions using two cages at each application distance of 10, 15, 20, and 25 meters, and a control group. Twenty-five female mosquitoes were used per repetition (cage). The sample was diluted to obtain a formulation containing 300 mL of Alfamurom + 100 mL of water + 100 mL of Natuinset. A total of 37.5 mL of this solution was applied to a final area of 750 m2 (equivalent to 500 mL per hectare). Knockdown assessment was conducted after 60 minutes, and mortality evaluation was performed 24 hours after insecticide application. The results showed 100% A. aegypti mortality at distances of 10, 15, 20, and 25 meters. The study was considered remarkable appropriate since there was no mortality in the control group. The A. aegypti female mosquitoes’ mortality in this experiment with alpha-cypermethrin (Alfamurom) using the ULV formulation was proved, and this formulation can be used in vector control actions alongside the adjuvant Natuinset.

Proton-sensing G Protein Coupled Receptors (GPCRs) sense changes in the extracellular pH to effect cell signaling for cellular homeostasis. They tend to be overexpressed in solid tumors associated with acidic extracellular pH, and are of direct interest as drug targets. How proton-sensing GPCRs sense extracellular acidification and activate upon protonation change is important to understand, because it may guide the design of therapeutics. Lack of publicly available experimental structures make it challenging to discriminate between conflicting mechanisms proposed for proton-binding, as main roles have been assigned to either an extracellular histidine cluster or to an internal carboxylic triad. Here we present a protocol to derive and evaluate structural models of the proton-sensing GPR68. This approach integrates state-of-the-art homology modeling with microsecond-timescale atomistic simulations, and with a detailed assessment of the compatibility of the structural models with known structural features of class A GPCRs. To decipher structural elements of potential interest for protonation-coupled conformational changes of GPR68, we used the best-compatible model as a starting point for independent atomistic simulations of GPR68 with different protonation states, and graph computations to characterize the response of GPR68 to changes in protonation. We found that GPR68 hosts an extended hydrogen-bond network that inter-connects the extracellular histidine cluster to the internal carboxylic triad, and which can even reach groups at the cytoplasmic G-protein binding site. Taken together, results suggest that GPR68 relies on dynamic, hydrogen-bond networks to inter-connect extracellular and internal proton-binding sites, and to elicit conformational changes at the cytoplasmic G-protein binding site.

Effective conservation requires reliable data and information on the status of biodiversity. The conservation of freshwater biodiversity lags behind terrestrial and marine biodiversity because data and information limitations are greatest in freshwater ecosystems. Given that freshwater ecosystems are inhabited by disproportionately more species than other ecosystems, paucity of data and information threatens many species and dependent ecosystem services. Data and information on freshwater biodiversity is limited mainly because few freshwater ecosystems are considered for regular monitoring. However, even existing data is scattered and in non-user-friendly formats, limiting accessibility and use. It is desirable to make freshwater biodiversity data and information accessible everywhere so that it attains its full potential in guiding conservation. To increase accessibility to freshwater biodiversity data in Uganda, we present 34 datasets covering three major freshwater taxa: zooplankton, macroinvertebrates, and fish within freshwater ecosystems in the country. The datasets provide occurrence records and corresponding abundance data where applicable for the three major groups. The datasets which are available through the Global Biodiversity Information Facility (GBIF) cover a long period from 1971-2021 and have a total of 56,104 occurrence records. Of these records, 8,674 records were published in 2022. The data were mobilized from primary biodiversity surveys conducted by scientists at the National Fisheries Resources Research Institute (NaFIRRI) in Uganda. The surveys covered most of the water bodies in the country. The datasets are envisaged to increase accessibility to data for freshwater conservation research, decision making and capacity building. The data has already found use in development of conservation tools and conservation status assessments.

Background: Atrial fibrillation is the most common arrhythmia and has been described as driver of cardiovascular morbidity and risk factor for cardiac device-related complications, as well as in transvenous lead extraction (TLE). Objectives: Aim of this study was to characterize the procedural outcome and risk-factors of patients with atrial fibrillation (AF) undergoing TLE. Methods: We performed a subgroup analysis of all AF patients in the GALLERY (GermAn Laser Lead Extraction RegistrY) database. Predictors for all-cause mortality were assessed. Results: A total number of 510 patients with AF were identified with a mean age of 74.0 ± 10.3 years. Systemic infection (38.4%) was the leading cause for TLE, followed by local infection (37.5%) and lead dysfunction (20.4%). Most of the patients (45.9%) presented with pacemaker systems to be extracted. The total number of leads was 1181 with a 2.3 ± 0.96 leads/patient. Clinical procedural success was achieved in 97.1%. Occurrence of major complications was 1.8% with a procedure-related mortality of 1.0%. All-cause mortality was high with 5.9% and septic shock being the most common cause. Systemic device infection (OR: 49.73; 95% CI: 6.56–377.09, p < 0.001), chronic kidney disease (CKD; OR: 2.67; 95% CI: 1.01–7.03, p = 0.048) and a body mass index < 21 kg/m2 (OR: 6.6; 95% CI: 1.68–25.87, p = 0.007) were identified as independent predictors for all-cause mortality. Conclusions: TLE in AF patients is effective and safe, but in patients with systemic infection the mortality due to septic shock is high. Systemic infection, CKD and body mass index 2 are risk factors for death in patient with AF undergoing TLE.

Myeloid-derived growth factor (MYDGF) is an angiogenic growth factor with therapeutic potential for ischemic tissue repair and the receptor is still unknown. Here the authors present the crystal structure of human MYDGF and identify its functional epitope through mutagenesis studies.

The design of urban public open spaces plays a key role in the development of micro-scale reactions to global phenomena (pandemic, climate change, etc.) that are currently reshaping the human habitat. Their transformability and healthy influence on the urban environment make them strategic nodes for acupunctural regeneration with systemic effects. Several methods, models, and indicators have been developed to face the complexity of these spaces, made up of tangible and intangible layers; however, there is a gap between theoretical investigation and the need for public administrations to devise feasible solutions, strategies, and guidelines. The paper focuses on this mediation, presenting, as a case study, an adopted methodology and the first results achieved according to guidelines for the regeneration of the system of squares in the historical center of Alessandria (Piedmont, Italy). In this case, a multidisciplinary approach and a Multi-Criteria Analysis (MCA) method, supported by geospatial analysis and GIS technology, have been employed to work as mediators for a participatory process which will involve public administration, stakeholders, experts, and researchers. The paper presents an overview of the workflow, with a focus on the first set of thematic indicators and an open conclusion. It will explain how they have been defined, integrated, and turned into a dialogic tool, with the aim of laying the foundation for the next stage of involvement by the public administration and stakeholders. Specific attention will be paid to the key role of vegetational and environmental parameters, which represents the requalification strategy’s backbone, for both local and systemic scales.

The massive presence and use of digital technologies in urban areas generate a growing amount of data. This new knowledge, from one side, assigns to the city the new posthuman image of a smart system; from the other side, the polyphony of data-sources interferes with the narrative structure of the city, increasing its complexity and multiplying both the possibilities of its explorations as the management and design of its futures. In fact, the integration of digital tools for the collection, analysis and visualization of data makes it possible to simulate possible scenarios of transformation. But how this system of fluctuating parameters relates to the physical space of the city? How these multiple virtual possibilities change the urban narrative? The intersection between digital mediation and physical urban space is the object of this paper, that moves from an interdisciplinary perspective, between narratology and urban design. We analyzed three case studies (Saint Petersburg, Bologna, Barcelona), representative of how the use of digital technologies transforms the representation of the city. In Saint Petersburg we have reshaped the (semantic) landscape of the city through Instagram data; in Bologna we have followed the (digital) traces of the temporary community of students, investigating the interaction and interference between the ‘univercity’ and the physical urban environment; in Barcelona we have analyzed an urban fragment (the street of La Rambla), considering it as a microcosmos of data.

Begitu mudah bagi debitur yang utangnya telah jatuh tempo dan dapat ditagih di pengadilan untuk dipailitkan berdasarkan pasal 2 ayat 1 dan pasal 8 ayat 4 No. 37 Tahun 2004 Tentang Kepailitan-PKPU. Syarat pailit yang dimuat seperti itu dapat dimanfaatkan debitur nakal atau debitur yang kondisi keuangannya lagi sulit untuk memohon pailit atas diri sendiri (Voluntary Bankruptcy Petition). Kepailitan yang hanya didasarkan pertimbangan pasal 2 ayat 1 dan pasal 8 ayat 4 UUK-PKPU tersebut tentu menyimpang dari prinsip kepailitan yang memandang bahwa kepailitan sebagai Commercial Exit From Financial Distress (jalan keluar dari persoalan yang membelit dalam keuangan). Oleh karenanya, Kepailitan bukan sebagai pranata untuk membangkrutkan suatu usaha. Terkait dalam hal ini perlu dipertimbangan keadaan insolven dari debitur. Debitur harus berada dalam keadaan insolven, baru kemudian hakim pengadilan dapat menjatuhkan pailit kepada debitur. Fakta mengungkapkan bahwa praktek hakim pengadilan dalam menerapkan prinsip Commercial Exit From Financial Distress di pengadilan Indonesia terhadap Voluntary Bankruptcy Petition masih berbeda-beda atau variatif. Putusan pengadilan dalam permohonan Voluntary Bankruptcy Petition PT Daya Guna Samudra menunjukkan bahwa dalam pertimbangan hukumnya pada perkara No.28/PAILIT/2004/PN.NIAGA.JKT.PST. Pada tanggal 16 Agustus 2004 tampak bahwa hakim menerapkan prinsip Commercial Exit From Fianncial. Dalam kasus Voluntary Bankruptcy Petition PT J & J Garment Indonesia dengan Nomor Perkara No.41/Pdt.Sus/Pailit/2013/PN.NIAGA.JKT.PST tertanggal 15 Agustus 2013, juga merupakan putusan yang tepat yaitu dengan menolak permohonan tersebut. Hakim memandang bahwa permohonan PT J & J Garmnet Indonesia tidak sertai dengan Account Audit dari Auditor Independen, sehingga tidak jelas bahwa debitur berada dalam keadaan insolven. Sementara putusan pengadilan terhadap permohonan Voluntary Bankruptcy Petition PT Mandala Airlines dengan Nomor Perkara No.48/Pdt.Sus.Pailit/2014/PN.Niaga.JKT.PSTbelum menerapkan Prinsip Commercial Exit From Financial Distress.

Chinook salmon (Oncorhynchus tshawytscha) farmed in New Zealand are known to develop abnormal spinal curvature late in seawater production. Its cause is presently unknown, but there is evidence to suggest a neuromuscular pathology. Using magnetic resonance imaging (MRI), we evaluated the relationship between soft tissue pathology and spinal curvature in farmed Chinook salmon. Regions of interest (ROIs) presenting as pathologic MRI signal hyper-intensity were identified from scans of 24 harvest-sized individuals: 13 with radiographically-detectable spinal curvature and 11 without. ROIs were excised from individuals using anatomical landmarks as reference points and histologically analysed. Pathologic MRI signal was observed more frequently in individuals with radiographic curvature (92%, n = 12) than those without (18%, n = 2), was localized to the peri-vertebral connective tissues and musculature, and presented as three forms: inflammation, fibrosis, or both. These pathologies are consistent with a chronic inflammatory process, such as that observed during recovery from a soft tissue injury, and suggest spinal curvature in farmed Chinook salmon may be associated with damage to and/or compromised integrity of the peri-vertebral soft tissues. Future research to ascertain the contributing factors is required., (© 2023 The Authors. Journal of Fish Diseases published by John Wiley & Sons Ltd.)

Marine organisms are under threat from a simultaneous combination of climate change stressors, including warming sea surface temperatures (SST), marine heatwave (MHW) episodes, and hypoxic events. This study sought to investigate the impacts of these stressors on the Australasian snapper ( C. auratus ) - a finfish species of high commercial and recreational importance, from the largest snapper fishery in Aotearoa New Zealand (SNA1). A MHW scenario was simulated from 21°C (current February SST average for north-eastern New Zealand) to a future predicted level of 25°C, with the whole-animal and mitochondrial metabolic performance of snapper in response to hypoxia and elevated temperature tested after 1-, 10-, and 30-days of thermal challenge. It was hypothesised that key indicators of snapper metabolic performance would decline after 1-day of MHW stress, but that partial recovery might arise as result of thermal plasticity after chronic (e.g., 30-day) exposures. In contrast to this hypothesis, snapper performance remained high throughout the MHW: 1) Aerobic metabolic scope increased after 1-day of 25°C exposure and remained high. 2) Hypoxia tolerance, measured as the critical O 2 pressure and O 2 pressure where loss of equilibrium occurred, declined after 1-day of warm-acclimation, but recovered quickly with no observable difference from the 21°C control following 30-days at 25°C. 3) The performance of snapper mitochondria was also maintained, with oxidative phosphorylation respiration and proton leak flux across the inner mitochondrial membrane of the heart remaining mostly unaffected. Collectively, the results suggest that heart mitochondria displayed resilience, or plasticity, in snapper chronically exposed to 25°C. Therefore, contrary to the notion of climate change having adverse metabolic effects, future temperatures approaching 25°C may be tolerated by C. auratus in Northern New Zealand. Even in conjunction with supplementary hypoxia, 25°C appears to represent a metabolically optimal temperature for this species., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Bowering, McArley, Devaux, Hickey and Herbert.)

Improving the feed conversion ratio (FCR; the amount of feed consumed relative to the amount of weight gain) can reduce both production costs and environmental impacts of farmed fish. The aim of this study was to investigate what drives FCR to understand how nutrients are retained, as well as the amount of oxygen consumed for digestion, absorption and assimilation (a metabolic process known as specific dynamic action, SDA). Feed-efficient and inefficient Chinook salmon (Oncorhynchus tshawytscha) in fresh water were identified using ballotini beads and X-radiography that tracked individual feed intake across three assessment periods under satiated feeding. This allowed a comparison of physiological traits and body composition between the two FCR phenotypes over two time points as Chinook salmon grew from 305 to 620 g. Fish with higher daily feed intake (DFI) had higher daily weight gain (DWG) as expected. Nonetheless, the relationship between FCR and DFI as well as FCR and DWG was variable between time points. FCR and DWG were not correlated at the first time point and were negatively correlated at the second time point. In contrast, FCR and DFI were positively correlated at the first time point but not the second. Despite this, efficient fish ate smaller meals and retained more protein, lipid and energy in their body tissues. There was no detectable difference in metabolism between the two FCR phenotypes with respect to minimal resting metabolic rate, maximum metabolic rate, aerobic scope, or SDA parameters. In conclusion, FCR is not consistently associated with growth and metabolic differences in freshwater Chinook salmon, but FCR-efficient fish retain more nutrients and consume smaller meals., (© 2022 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of Fisheries Society of the British Isles.)

Spinal anomalies are a recognised source of downgrading in finfish aquaculture, but identifying their cause(s) is difficult and often requires extensive knowledge of the underlying pathology. Late-onset spinal curvatures (lordosis, kyphosis, scoliosis) can affect up to 40% of farmed New Zealand Chinook (king) salmon (Oncorhynchus tshawytscha) at harvest, but little is known about their pathogenesis. Curvature development was radiographically documented in two related cohorts of commercially-farmed Chinook salmon throughout seawater production to determine (1) the timing of radiographic onset and relationships between (2) the curvature types, (3) the spinal regions in which they develop and (4) their associations with co-existing vertebral body anomalies (vertebral compression, fusion and vertical shift). Onset of curvature varied between individuals, but initially occurred eight months post-seawater transfer. There were strong associations between the three curvature types and the four recognised spinal regions: lordosis was predominantly observed in regions (R)1 and R3, kyphosis in R2 and R4, manifesting as a distinct pattern of alternating lordosis and kyphosis from head to tail. This was subsequently accompanied by scoliosis, which primarily manifested in spinal regions R2 and R3, where most of the anaerobic musculature is concentrated. Co-existing vertebral body anomalies, of which vertebral compression and vertical shift were most common, appeared to arise either independent of curvature development or as secondary effects. Our results suggest that spinal curvature in farmed New Zealand Chinook salmon constitutes a late-onset, rapidly-developing lordosis-kyphosis-scoliosis (LKS) curvature complex with a possible neuromuscular origin.

Acute heat shock has previously been shown to improve subsequent low O2 (hypoxia) tolerance in an intertidal fish species, a process known as cross-tolerance, but it is not known whether this is a widespread phenomenon. This study examined whether a rock pool specialist, the triplefin fish Bellapiscis medius, exhibits heat shock induced cross-tolerance to hypoxia, i.e., longer time to loss of equilibrium (LOE) and lower critical O2 saturation (Scrit) after recovering from an acute heat challenge. Non-heat shock controls had a median time to loss of equilibrium (LOE50) of 54.4 min under severe hypoxia (7% of air saturation) and a Scrit of 15.8% air saturation. Contrary to expectations, however, treatments that received an 8 or 10°C heat shock showed a significantly shorter LOE50 in hypoxia (+8°C = 41.5 min; +10°C = 28.7 min) and no significant change in Scrit (+8°C = 17.0% air saturation; +10°C = 18.3% of air saturation). Thus, there was no evidence of heat shock induced cross-tolerance to hypoxia in B. medius because exposure to acute heat shock impaired hypoxia tolerance., Competing Interests: The authors have declared that no competing interests exist.

To examine how different fish coping strategies respond to salinity challenge, olive flounder ( Paralichthys olivaceus ) with active coping style (AC) and passive coping style (PC) were transferred from seawater (SW) to freshwater (FW) and their behavior and physiology were analyzed. Different behavioral coping strategies, in terms of escape and feeding tendencies, were confirmed in AC and PC fish without FW exposure. Differences in swimming distance between AC and PC flounder were then assessed after 1 and 2 days of FW transfer. Plasma parameters and branchial gene expression were also determined 2, 5, 8, and 14 days after transfer, with comparisons between AC and PC fish and against a SW-acclimated control group. The results showed that: (1) PC flounder exhibited a significant reduction in swimming activity, while AC flounder significantly increased locomotion 2 days after transfer. (2) The plasma osmolality and plasma ionic (Na + and Cl - ) concentration of FW-acclimated PC flounder declined in a continuous fashion over time but this contrasted against the plasma parameters of AC flounder which fluctuated below the baseline level of a SW-acclimated control group. (3) The expression of NKA-α1 and NHE-3-like mRNA in PC flounder gill increased significantly from 5 days, but the expression of these two genes in AC flounder only increased after 8 days of transfer. (4) There were no remarkable differences observed in Rhcg expressions between AC and PC flounder. This study indicates for the first time that PC flounder adopt a "freeze-passive tolerance" strategy while AC flounder adopt a "flight-active resistance" defense strategy in response to salinity challenge., (Copyright © 2019 Zeng, Herbert and Lu.)

Decreased oxygen (O 2 ) availability (hypoxia) is common in rock pools and challenges the aerobic metabolism of fishes living in these habitats. In this study, the critical O 2 tension (P crit ), a whole animal measure of the aerobic contribution to hypoxia tolerance, was compared between four New Zealand triplefin fishes including an intertidal specialist (Bellapiscis medius), an occasional intertidal inhabitant (Forsterygion lapillum) and two exclusively subtidal species (F. varium and F. malcolmi). The intertidal species had lower P crit values than the subtidal species indicating traits to meet resting O 2 demands at lower O 2 tensions. While resting O 2 demand (standard metabolic rate; SMR) did not show a major difference between species, the intertidal species had higher maximal rates of O 2 consumption ([Formula: see text]) and higher aerobic metabolic scope (MS). The high O 2 extractive capacity of the intertidal species was associated with increased blood O 2 carrying capacity (i.e., higher Hb concentration), in addition to higher mass-specific gill surface area and thinner gill secondary lamellae that collectively conveyed a higher capacity for O 2 flux across the gills. The specialist intertidal species B. medius also had higher glycogen stores in both white muscle and brain tissues, suggesting a greater potential to generate ATP anaerobically and survive in rock pools with O 2 tensions less than P crit . Overall, this study shows that the superior P crit of intertidal triplefin species is not linked to a minimisation of SMR, but is instead associated with an increased O 2 extractive capacity of the cardiorespiratory system (i.e., [Formula: see text], MS, Hb and gill O 2 flux).

Daytime low tides that lead to high-temperature events in stranded rock pools often co-occur with algae-mediated hyperoxia as a result of strong solar radiation. Recent evidence shows aerobic metabolic scope (MS) can be expanded under hyperoxia in fish but so far this possibility has not been examined in intertidal species despite being an ecologically relevant scenario. Furthermore, it is unknown whether hyperoxia increases the upper thermal tolerance limits of intertidal fish and, therefore, their ability to withstand extreme high-temperature events. Therefore, we measured the metabolic response (mass-specific rate of oxygen consumption, Ṁ O 2 ) to thermal ramping (21-29°C) and the upper thermal tolerance limit ( U TL ) of two intertidal triplefin fishes ( Bellapiscis medius and Forsterygion lapillum ) under hyperoxia and normoxia. Hyperoxia increased maximal oxygen consumption ( Ṁ O 2 ,max ) and MS of each species at ambient temperature (21°C) but also after thermal ramping to elevated temperatures such as those observed in rock pools (29°C). While hyperoxia did not provide a biologically meaningful increase in upper thermal tolerance of either species (>31°C under all conditions), the observed expansion of MS at 29°C under hyperoxia could potentially benefit the aerobic performance, and hence the growth and feeding potential, etc., of intertidal fish at non-critical temperatures. That hyperoxia does not increase upper thermal tolerance in a meaningful way is cause for concern as climate change is expected to drive more extreme rock pool temperatures in the future and this could present a major challenge for these species., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2018. Published by The Company of Biologists Ltd.)

Intertidal fish species face gradual chronic changes in temperature and greater extremes of acute thermal exposure through climate-induced warming. As sea temperatures rise, it has been proposed that whole-animal performance will be impaired through oxygen and capacity limited thermal tolerance [OCLTT; reduced aerobic metabolic scope (MS)] and, on acute exposure to high temperatures, thermal safety margins may be reduced because of constrained acclimation capacity of upper thermal limits. Using the New Zealand triplefin fish ( Forsterygion lapillum ), this study addressed how performance in terms of growth and metabolism (MS) and upper thermal tolerance limits would be affected by chronic exposure to elevated temperature. Growth was measured in fish acclimated (12 weeks) to present and predicted future temperatures and metabolic rates were then determined in fish at acclimation temperatures and with acute thermal ramping. In agreement with the OCLTT hypothesis, chronic exposure to elevated temperature significantly reduced growth performance and MS. However, despite the prospect of impaired growth performance under warmer future summertime conditions, an annual growth model revealed that elevated temperatures may only shift the timing of high growth potential and not the overall annual growth rate. While the upper thermal tolerance (i.e. critical thermal maxima) increased with exposure to warmer temperatures and was associated with depressed metabolic rates during acute thermal ramping, upper thermal tolerance did not differ between present and predicted future summertime temperatures. This suggests that warming may progressively decrease thermal safety margins for hardy generalist species and could limit the available habitat range of intertidal populations., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2017. Published by The Company of Biologists Ltd.)

The clownfish-anemone association exemplifies a symbiosis where both members benefit from nutrient exchange and protection from predators. Clownfish also perform aeration-like behaviour in their host anemones at night, but it is not yet known whether this is stimulated by the onset of hypoxia, and whether both members benefit from O 2 replenishment. Oxygen at 3 distances above the sea anemone Entacmaea quadricolor (0.2, 1.2 and 2.2 cm) therefore was measured under 3 light levels (photon flux density = 0, 55 and 110 µmol m -2 s -1 ), with and without the anemonefish Amphiprion frenatus. Hypoxia (O 2  < 50% air saturation) was recorded in the anemone, but only at 0.2 cm away from the anemone surface under dark conditions when A. frenatus was absent. This localised layer of hypoxia was eliminated by the presence of A. frenatus exhibiting aeration-like behaviour. Respirometry revealed that A. frenatus is extremely hypoxia tolerant (S crit  = 14.3% at 25 °C), suggesting that aeration behaviour does not provide a major metabolic advantage to clownfish because they do not breathe water at 0.2 cm and are not metabolically constrained by O 2 at distances ≥ 1.2 cm. That the aeration behaviour of A. frenatus facilitates only the metabolism of its O 2 -conforming host reveals a unique aspect of this symbiotic relationship.

Turbidity as a result of increased suspended sediments in coastal waters is an environmental stress of worldwide concern. Recent research on fish suggests that detrimental changes to gill structure can occur in turbid waters, with speculation that these alterations diminish fitness variables, such as growth and development, by negatively impacting the O 2 uptake capacity (respiration) of fish. Specifically to address this unknown, the impact of turbid water on the gill structure, somatic growth rate and O 2 uptake rates of a juvenile sparid species ( Pagrus auratus ) was addressed following exposure to five different turbidity treatments (<10, 20, 40, 60 or 80 nephelometric turbidity units) for 30 days. Significant gill structural change was apparent with a progressive increase in turbidity and was quantified as a reduction in lamellar density, as well as an increase in basal hyperplasia, epithelial lifting and increased oxygen diffusion distance across the lamellae. The weight of control fish did not change throughout the experiment, but all fish exposed to turbid waters lost weight, and weight loss increased with nephelometric turbidity units, confirming that long-term turbidity exposure is detrimental to growth productivity. The growth of fish could be impacted in a variety of ways, but the specific hypothesis that structural alteration of the gills impairs O 2 uptake across the gills and limits growth fitness was not supported because there was no measurable difference in the standard metabolic rate, maximal metabolic rate, aerobic metabolic scope or critical oxygen saturation limit of fish measured in clear water after 30 days of exposure. Although impaired O 2 uptake as a result of structurally adjusted gills is unlikely to be the cause of poor fish growth, the exact mechanism by which growth productivity is affected in turbid conditions remains unclear and warrants further investigation.

Understanding how mitochondrial function alters with acclimation may provide insight to the limits these organelles place on temperate fish hearts facing seasonal temperature fluctuations. This investigation determined if compromised cardiac mitochondrial function contributed to heart failure (HF) in the New Zealand wrasse Notolabrus celidotus acclimated at their mean summer and winter ocean temperatures. To test this hypothesis, fish were acclimated to cold (CA, 15°C) and warm (WA, 21°C) temperatures. The temperature of HF was determined by Doppler sonography and mitochondrial function in permeabilised cardiac fibres was tested using high resolution respirometry. Heat stress mediated HF occurred at a THF of 26.7±0.4°C for CA fish, and at 28.2±0.6°C for WA fish. Biochemical analyses also revealed that WA fish had elevated resting plasma lactate indicating an increased dependence on anaerobic pathways. When cardiac fibres were tested with increasing temperatures, apparent breakpoints in the respiratory control ratio (RCR-I) with substrates supporting complex I (CI) oxygen flux occurred below the THF for both acclimated groups. While WA cardiac mitochondria were less sensitive to increasing temperature for respirational flux supported by CI, Complex II, and chemically uncoupled flux, CA fish maintained higher RCRs at higher temperatures. We conclude that while acclimation to summer temperatures does alter cardiac mitochondrial function in N. celidotus, these changes need not be beneficial in terms of oxidative phosphorylation efficiency and may come at an energetic cost, which would be detrimental in the face of further habitat warming., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Induced-swimming can improve the growth and feed conversion efficiency of finfish aquaculture species, such as salmonids and Seriola sp., but some species, such as Atlantic cod, show no or a negative productivity response to exercise. As a possible explanation for these species-specific differences, a recent hypothesis proposed that the applicability of exercise training, as well as the exercise regime for optimal growth gain (ERopt growth), was dependent upon the size of available aerobic metabolic scope (AMS). This study aimed to test this hypothesis by measuring the growth and swimming metabolism of hapuku, Polyprion oxygeneios, to different exercise regimes and then reconciling the metabolic costs of swimming and specific dynamic action (SDA) against AMS. Two 8-week growth trials were conducted with ERs of 0.0, 0.25, 0.5, 0.75, 1, and 1.5 body lengths per second (BL s(-1)). Fish in the first trial showed a modest 4.8% increase in SGR over static controls in the region 0.5-0.75 BL s(-1) whereas the fish in trial 2 showed no significant effect of ER on growth performance. Reconciling the SDA of hapuku with the metabolic costs of swimming showed that hapuku AMS is sufficient to support growth and swimming at all ERs. The current study therefore suggests that exercise-induced growth is independent of AMS and is driven by other factors.

Oxygen demand generally increases in ectotherms as temperature rises in order to sustain oxidative phosphorylation by mitochondria. The thermal plasticity of ectotherm metabolism, such as that of fishes, dictates a species survival and is of importance to understand within an era of warming climates. Within this study the whole animal O2 consumption rate of a common New Zealand intertidal triplefin fish, Forsterygion lapillum, was investigated at different acclimation temperatures (15, 18, 21, 24 or 25 °C) as a commonly used indicator of metabolic performance. In addition, the mitochondria within permeabilised skeletal muscle fibres of fish acclimated to a moderate temperature (18 °C Cool acclimation group-CA) and a warm temperature (24 °C. Warm acclimation group-WA) were also tested at 18, 24 and 25 °C in different states of coupling and with different substrates. These two levels of analysis were carried out to test whether any peak in whole animal metabolism reflected the respiratory performance of mitochondria from skeletal muscle representing the bulk of metabolic tissue. While standard metabolic rate (SMR- an indicator of total maintenance metabolism) and maximal metabolic rate ([Formula: see text]O2 max) both generally increased with temperature, aerobic metabolic scope (AMS) was maximal at 24 °C, giving the impression that whole animal (metabolic) performance was optimised at a surprisingly high temperature. Mitochondrial oxygen flux also increased with increasing assay temperature but WA fish showed a lowered response to temperature in high flux states, such as those of oxidative phosphorylation and in chemically uncoupled states of respiration. The thermal stability of mitochondria from WA fish was also noticeably greater than CA fish at 25 °C. However, the predicted contribution of respirational flux to ATP synthesis remained the same in both groups and WA fish showed higher anaerobic activity as a result of high muscle lactate loads in both rested and exhausted states. CA fish had a comparably lower level of resting lactate and took 30 % longer to fatigue than WA fish. Despite some apparent acclimation capacity of skeletal muscle mitochondria, the ATP synthesis capacity of this species is constrained at high temperatures, and that a greater fraction of metabolism in skeletal muscle appears to be supported anaerobically at higher temperatures. The AMS peak at 24 °C does not therefore represent utilisation efficiency of oxygen but, rather, the temperature where scope for oxygen flow is greatest.