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The melting of the Greenland Ice Sheet is accelerating, with glaciers shifting from marine to land termination and potential consequences for fjord ecosystems downstream. Monthly samples in 2016 in two fjords in southwest Greenland show that subglacial discharge from marine-terminating glaciers sustains high phytoplankton productivity that is dominated by diatoms and grazed by larger mesozooplankton throughout summer. In contrast, melting of land-terminating glaciers results in a fjord ecosystem dominated by bacteria, picophytoplankton and smaller zooplankton, which has only one-third of the annual productivity and half the CO 2 uptake compared to the fjord downstream from marine-terminating glaciers., Competing Interests: Competing interestsThe authors declare no competing interests., (© The Author(s) 2023.)

The chemical speciation of iron (Fe) in oceans is influenced by ambient pH, dissolved oxygen, and the concentrations and strengths of the binding sites of dissolved organic matter (DOM). Here, we derived new nonideal competitive adsorption (NICA) constants for Fe(III) binding to marine DOM via pH-Fe titrations. We used the constants to calculate Fe(III) speciation and derive the apparent Fe(III) solubility (SFe( III ) app ) in the ambient water column across the Peruvian shelf and slope region. We define SFe( III ) app as the sum of aqueous inorganic Fe(III) species and Fe(III) bound to DOM at a free Fe (Fe 3+ ) concentration equal to the limiting solubility of Fe hydroxide (Fe(OH) 3 (s)). A ca. twofold increase in SFe( III ) app in the oxygen minimum zone (OMZ) compared to surface waters is predicted. The increase results from a one order of magnitude decrease in H + concentration which impacts both Fe(III) hydroxide solubility and organic complexation. A correlation matrix suggests that changes in pH have a larger impact on SFe( III ) app and Fe(III) speciation than DOM in this region. Using Fe(II) measurements, we calculated ambient DFe(III) and compared the value with the predicted SFe( III ) app . The underlying distribution of ambient DFe(III) largely reflected the predicted SFe( III ) app , indicating that decreased pH as a result of OMZ intensification and ocean acidification may increase SFe( III ) app with potential impacts on surface DFe inventories.

Approximately half of the freshwater discharged from the Greenland and Antarctic Ice Sheets enters the ocean subsurface as a result of basal ice melt, or runoff draining via the grounding line of a deep ice shelf or marine-terminating glacier. Around Antarctica and parts of northern Greenland, this freshwater then experiences prolonged residence times in large cavities beneath floating ice tongues. Due to the inaccessibility of these cavities, it is unclear how they moderate the freshwater associated supply of nutrients such as iron (Fe) to the ocean. Here, we show that subglacial dissolved Fe export from Nioghalvfjerdsbrae (the '79°N Glacier') is decoupled from particulate inputs including freshwater Fe supply, likely due to the prolonged ~162-day residence time of Atlantic water beneath Greenland's largest floating ice-tongue. Our findings indicate that the overturning rate and particle-dissolved phase exchanges in ice cavities exert a dominant control on subglacial nutrient supply to shelf regions.

A spectrophotometric approach for quantification of dissolved manganese (DMn) with 1-(2-pyridylazo)-2-naphthol (PAN) has been adapted for in situ application in coastal and estuarine waters. The analyser uses a submersible microfluidic lab-on-chip device, with low power (~ 1.5 W) and reagent consumption (63 µL per sample). Laboratory characterization showed an absorption coefficient of 40,838 ± 1127 L⋅mol -1 ⋅cm -1 and a detection limit of 27 nM, determined for a 34.6 mm long optical detection cell. Laboratory tests showed that long-term stability of the PAN reagent was achieved by addition of 4% v/v of a non-ionic surfactant (Triton-X100). To suppress iron (Fe) interferences with the PAN reagent, the Fe(III) masking agents deferoxamine mesylate (DFO-B) or disodium 4,5-dihydroxy-1,3-benzenedisulfonate (Tiron) were added and their Fe masking efficiencies were investigated. The analyser was tested during a deployment over several weeks in Kiel Fjord (Germany), with successful acquisition of 215 in situ data points. The time series was in good agreement with DMn concentrations determined from discretely collected samples analysed via inductively coupled plasma mass spectrometry (ICP-MS), exhibiting a mean accuracy of 87% over the full deployment duration (with an accuracy of > 99% for certain periods) and clear correlations to key hydrographic parameters.

Climate change has led to a ~ 40% reduction in summer Arctic sea-ice cover extent since the 1970s. Resultant increases in light availability may enhance phytoplankton production. Direct evidence for factors currently constraining summertime phytoplankton growth in the Arctic region is however lacking. GEOTRACES cruise GN05 conducted a Fram Strait transect from Svalbard to the NE Greenland Shelf in summer 2016, sampling for bioessential trace metals (Fe, Co, Zn, Mn) and macronutrients (N, Si, P) at ~ 79°N. Five bioassay experiments were conducted to establish phytoplankton responses to additions of Fe, N, Fe + N and volcanic dust. Ambient nutrient concentrations suggested N and Fe were deficient in surface seawater relative to typical phytoplankton requirements. A west-to-east trend in the relative deficiency of N and Fe was apparent, with N becoming more deficient towards Greenland and Fe more deficient towards Svalbard. This aligned with phytoplankton responses in bioassay experiments, which showed greatest chlorophyll-a increases in + N treatment near Greenland and + N + Fe near Svalbard. Collectively these results suggest primary N limitation of phytoplankton growth throughout the study region, with conditions potentially approaching secondary Fe limitation in the eastern Fram Strait. We suggest that the supply of Atlantic-derived N and Arctic-derived Fe exerts a strong control on summertime nutrient stoichiometry and resultant limitation patterns across the Fram Strait region.

Background: Electroconvulsive therapy (ECT) is recommended in treatment guidelines as an efficacious therapy for treatment-resistant depression. However, it has been associated with loss of autobiographical memory and short-term reduction in new learning., Aims: To provide clinically useful guidelines to aid clinicians in informing patients regarding the cognitive side-effects of ECT and in monitoring these during a course of ECT, using complex data., Method: A Committee of clinical and academic experts from Australia and New Zealand met to the discuss the key issues pertaining to ECT and cognitive side-effects. Evidence regarding cognitive side-effects was reviewed, as was the limited evidence regarding how to monitor them. Both issues were supplemented by the clinical experience of the authors., Results: Meta-analyses suggest that new learning is impaired immediately following ECT but that group mean scores return at least to baseline by 14 days after ECT. Other cognitive functions are generally unaffected. However, the finding of a mean score that is not reduced from baseline cannot be taken to indicate that impairment, particularly of new learning, cannot occur in individuals, particularly those who are at greater risk. Therefore, monitoring is still important. Evidence suggests that ECT does cause deficits in autobiographical memory. The evidence for schedules of testing to monitor cognitive side-effects is currently limited. We therefore make practical recommendations based on clinical experience., Conclusions: Despite modern ECT techniques, cognitive side-effects remain an important issue, although their nature and degree remains to be clarified fully. In these circumstances it is useful for clinicians to have guidance regarding what to tell patients and how to monitor these side-effects clinically.

Rivers are a major supplier of particulate and dissolved material to the ocean, but their role as sources of bio-essential dissolved iron (dFe) is thought to be limited due to rapid, efficient Fe removal during estuarine mixing. Here, we use trace element and radium isotope data to show that the influence of the Congo River margin on surface Fe concentrations is evident over 1000 km from the Congo outflow. Due to an unusual combination of high Fe input into the Congo-shelf-zone and rapid lateral transport, the Congo plume constitutes an exceptionally large offshore dFe flux of 6.8 ± 2.3 × 10 8  mol year -1 . This corresponds to 40 ± 15% of atmospheric dFe input into the South Atlantic Ocean and makes a higher contribution to offshore Fe availability than any other river globally. The Congo River therefore contributes significantly to relieving Fe limitation of phytoplankton growth across much of the South Atlantic.

Marine phytoplankton growth at high latitudes is extensively limited by iron availability. Icebergs are a vector transporting the bioessential micronutrient iron into polar oceans. Therefore, increasing iceberg fluxes due to global warming have the potential to increase marine productivity and carbon export, creating a negative climate feedback. However, the magnitude of the iceberg iron flux, the subsequent fertilization effect and the resultant carbon export have not been quantified. Using a global analysis of iceberg samples, we reveal that iceberg iron concentrations vary over 6 orders of magnitude. Our results demonstrate that, whilst icebergs are the largest source of iron to the polar oceans, the heterogeneous iron distribution within ice moderates iron delivery to offshore waters and likely also affects the subsequent ocean iron enrichment. Future marine productivity may therefore be not only sensitive to increasing total iceberg fluxes, but also to changing iceberg properties, internal sediment distribution and melt dynamics.

Purpose of Review: To understand the current situation, needs and challenges in the area of postgraduate training in psychiatry in Asia and identify implementable solutions.Leaders in psychiatric education from nine Asia Pacific countries prepared country reports, based on a suggested list of items and met for a day to discuss and identify implementable solutions to improve the current unsatisfactory status of postgraduate training in psychiatry., Recent Findings: Except Japan, all the other countries have a very low number of psychiatrists per 100 000 population - far lower than the global target of 10 psychiatrist per 100 000 population. The undergraduate teaching in psychiatry in majority of the countries is restricted to 20 h of lectures given during the 4-6 semester and 2-3 weeks of clinical ward placements. The duration as well as the overall quality of postgraduate training and methods of assessment and accreditation varies widely across and within countries., Summary: Numerous gaps that need to be addressed to enhance the quality of psychiatrists trained in Asia were identified. There is a need to have uniform minimum standards of training and mechanisms of mutual support, for not only training but also academics and research activities in Asia.

Runoff from the Greenland Ice Sheet (GrIS) is thought to enhance marine productivity by adding bioessential iron and silicic acid to coastal waters. However, experimental data suggest nitrate is the main summertime growth-limiting resource in regions affected by meltwater around Greenland. While meltwater contains low nitrate concentrations, subglacial discharge plumes from marine-terminating glaciers entrain large quantities of nitrate from deep seawater. Here, we characterize the nitrate fluxes that arise from entrainment of seawater within these plumes using a subglacial discharge plume model. The upwelled flux from 12 marine-terminating glaciers is estimated to be >1000% of the total nitrate flux from GrIS discharge. This plume upwelling effect is highly sensitive to the glacier grounding line depth. For a majority of Greenland's marine-terminating glaciers nitrate fluxes will diminish as they retreat. This decline occurs even if discharge volume increases, resulting in a negative impact on nitrate availability and thus summertime marine productivity.

The term 'mood stabiliser' is ill-defined and lacks clinical utility. We propose a framework to evaluate medications and effectively communicate their mood stabilising properties - their acute and prophylactic efficacy across the domains of mania and depression. The standardised framework provides a common definition to facilitate research and clinical practice., Declaration of Interest: The Treatment Algorithm Group (TAG) was supported logistically by Servier who provided financial assistance with travel and accommodation for those TAG members travelling interstate or overseas to attend the meeting in Sydney (held on 18 November 2017). None of the committee were paid to participate in this project and Servier have not had any input into the content, format or outputs from this project.

Introduction: In December 2015, the Royal Australian and New Zealand College of Psychiatrists published a comprehensive set of mood disorder clinical practice guidelines for psychiatrists, psychologists and mental health professionals. This guideline summary, directed broadly at primary care physicians, is an abridged version that focuses on bipolar disorder. It is intended as an aid to the management of this complex disorder for primary care physicians working in collaboration with psychiatrists to implement successful long term management. Main recommendations: The guidelines address the main phases of bipolar disorder with a particular emphasis on long term management, and provide specific clinical recommendations. Mania: All physicians should be able to detect its early signs so that treatment can be initiated promptly. At the outset, taper and cease medications with mood-elevating properties and institute measures to reduce stimulation, and transfer the patient to specialist care. Bipolar depression: Treatment is complicated and may require trialling treatment combinations. Monotherapy with mood-stabilising agents or second generation antipsychotics has demonstrated efficacy but using combinations of these agents along with antidepressants is sometimes necessary to achieve remission. Commencing adjunctive structured psychosocial treatments in this phase is benign and likely effective. Long term management: Physicians should adjust treatment to prevent the recurrence of manic and/or depressive symptoms and optimise functional recovery. Closely monitor the efficacy of pharmacological and psychological treatments, adverse effects and compliance. Changes in management as a result of the guidelines: The guidelines position bipolar disorder as part of a spectrum of mood disorders and provide a longitudinal perspective for assessment and treatment. They provide new management algorithms for the maintenance phase of treatment that underscore the importance of ongoing monitoring to achieve prophylaxis. As a first line treatment, lithium remains the most effective medication for the prevention of relapse and potential suicide, but requires nuanced management from both general practitioners and specialists. The guidelines provide clarity and simplicity for the long term management of bipolar disorder, incorporating the use of new medications and therapies alongside established treatments.

Hydrogen peroxide (H 2 O 2 ) is present ubiquitously in marine surface waters where it is a reactive intermediate in the cycling of many trace elements. Photochemical processes are considered the dominant natural H 2 O 2 source, yet cannot explain nanomolar H 2 O 2 concentrations below the photic zone. Here, we determined the concentration of H 2 O 2 in full depth profiles across three ocean basins (Mediterranean Sea, South Atlantic and South Pacific Oceans). To determine the accuracy of H 2 O 2 measurements in the deep ocean we also re-assessed the contribution of interfering species to 'apparent H 2 O 2 ', as analysed by the luminol based chemiluminescence technique. Within the vicinity of coastal oxygen minimum zones, accurate measurement of H 2 O 2 was not possible due to interference from Fe(II). Offshore, in deep (>1000 m) waters H 2 O 2 concentrations ranged from 0.25 ± 0.27 nM (Mediterranean, Balearics-Algeria) to 2.9 ± 2.2 nM (Mediterranean, Corsica-France). Our results indicate that a dark, pelagic H 2 O 2 production mechanism must occur throughout the deep ocean. A bacterial source of H 2 O 2 is the most likely origin and we show that this source is likely sufficient to account for all of the observed H 2 O 2 in the deep ocean.

Family members are known to be highly influential in the development of sport expertise. To date, much of the research in this area has focused on parents, with less known about sibling influences on expertise. This investigation explored associations between sport expertise, sibling characteristics, and sibling participation in sport and physical activity. Athletes representing three skill levels provided details of sibling characteristics and participation in sport and physical activity via the Developmental History of Athletes Questionnaire. Elite athletes were more likely to be later-born children, while pre-elite and non-elite athletes were more likely to be first-born. Compared with siblings of non-elite athletes, siblings of elite athletes were more likely to have participated in regular physical activity and were more likely to have participated in sport at the pre-elite and elite levels. These results suggest siblings may play a key role in sport expertise development., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Depressive symptoms frequently accompany physical illness, but the association between the two is complex. The combination has detrimental implications for the patient's health outcome, quality of life, medical treatment and health care use. The presence of physical symptoms of the medical illness can lead to challenges in recognising and diagnosing depression. This is best dealt with by placing greater emphasis on the psychological symptoms of depression. Recognition may be improved through use of appropriate screening tools for depression in medically ill patients. The management of depression in the setting of medical illness involves both general and specific approaches. General approaches include optimal treatment of the medical illness, exclusion of treatments that are associated with depressive symptoms, and simple general health strategies aimed at improving sleep and exercise. Good evidence exists for selective psychotherapeutic approaches and antidepressant treatments, but care is required to avoid drug-drug and illness-drug interactions with the latter.

The quiet eye is a perceptual skill associated with expertise and superior performance; however, little is known about the transfer of quiet eye across domains. We attempted to replicate previous skill-based differences in quiet eye and investigated whether transfer of motor and perceptual skills occurs between similar tasks. Throwing accuracy and quiet eye duration for skilled and less-skilled basketball players were examined in basketball free throw shooting and the transfer task of dart throwing. Skilled basketball players showed significantly higher throwing accuracy and longer quiet eye duration in the basketball free throw task compared to their less-skilled counterparts. Further, skilled basketball players showed positive transfer from basketball to dart throwing in accuracy but not in quiet eye duration. Our results raise interesting questions regarding the measurement of transfer between skills.

Purpose: Refractory temporal lobe epilepsy (TLE) is often associated with hippocampal sclerosis (HS). Patients with major depression (MD) may also show structural abnormalities in the limbic system. Co-occurrence of TLE with HS and MD is not uncommon. We have investigated the clinical and morphological characteristics of TLE patients in relation to MD., Methods: 34 TLE patients with HS were assessed at a Comprehensive Epilepsy Programme. All relevant clinical data were obtained, including the history of antecedent events to epilepsy. MD was diagnosed based on detailed psychiatric investigation. MRI was used to measure the volume and tissue signal (T2 relaxometry) of the hippocampus and amygdala. The imaging data were expressed as a percentage of the values obtained in a series of 55 controls., Results: A history of MD was present in 15 (44%) of 34 patients. Patients with MD had a longer duration of their epilepsy (p<0.05) and a lower frequency of antecedent events (13% with MD, 58% without MD, p<0.05). Both groups had a similar degree of ipsilateral HS (small hippocampal volume, increased hippocampal T2 relaxation time) and demonstrated bilateral amygdaloid atrophy. However, the contralateral amygdala showed lower signal in the presence of MD (97 (9) ms; no MD 103 (8) ms; ANCOVA, p = 0.02)., Conclusion: The integrity of the amygdala may influence mood disturbances in TLE patients with HS, as depression was associated with a relative preservation of the contralateral amygdala. In contrast, hippocampal abnormalities were not related to the presence of depression.

Nutritional supplements are popular among athletes participating in a wide variety of sports. Creatine is one of the most commonly used dietary supplements, as it has been shown to be beneficial in improving performance during repeated bouts of high-intensity anaerobic activity. This review examines the specific effects of creatine supplementation on swimming performance, and considers the effects of creatine supplementation on various measures of power development in this population. Research performed on the effect of creatine supplementation on swimming performance indicates that whilst creatine supplementation is ineffective in improving performance during a single sprint swim, dietary creatine supplementation may benefit repeated interval swim set performance. Considering the relationship between sprint swimming performance and measurements of power, the effect of creatine supplementation on power development in swimmers has also been examined. When measured on a swim bench ergometer, power development does show some improvement following a creatine supplementation regime. How this improvement in power output transfers to performance in the pool is uncertain. Although some evidence exists to suggest a gender effect on the performance improvements seen in swimmers following creatine supplementation, the majority of research indicates that male and female swimmers respond equally to supplementation. A major limitation to previous research is the lack of consideration given to the possible stroke dependant effect of creatine supplementation on swimming performance. The majority of the research conducted to date has involved examination of the freestyle swimming stroke only. The potential for performance improvements in the breaststroke and butterfly swimming strokes is discussed, with regards to the biomechanical differences and differences in efficiency between these strokes and freestyle. Key PointsCreatine supplementation does not improve single sprint swimming performance.Creatine supplementation does improve repeated interval swim set performance.Creatine supplementation does improve power development in swimmers when measured on a swim bench ergometer.As a result of the high energy demands of the butterfly and breaststroke competitive swimming styles, potentially, the benefits associated with creatine supplementation and swimming performance could be greater when swimming butterfly or breaststroke, compared to the commonly examined freestyle swimming stroke.

The authors studied six patients with refractory temporal lobe epilepsy and postictal psychosis using quantitative MRI and histopathology, and compared the results with 45 patients with temporal lobe epilepsy without postictal psychosis. Total hippocampal volumes were not different between the two groups. However, patients with postictal psychosis had a relatively preserved anterior hippocampus, and temporal lobe dysplasia was more frequent (p = 0.006, chi-square test). These findings may be associated with the clinical symptoms.

This study examined whether stroke lesions involving left hemisphere prefrontal or basal ganglia structures are associated with poststroke depression. A consecutive series of first-ever stroke patients with single small lesions on CT scan were examined for the presence and severity of poststroke depressive disorder. Lesions involving left prefrontal or basal ganglia structures were compared with other left hemisphere lesions and all right hemisphere lesions. Forty-one patients were examined. Patients with lesions involving left hemisphere prefrontal or basal ganglia structures had a higher frequency of depressive disorder (9/12; 75%) than other left hemisphere lesions (1/12; 8%) or those with right hemisphere lesions (5/17; 29%), P = 0.002. These findings suggest that damage to neural pathways within left hemisphere prefrontal or basal ganglia structures is associated with depressed mood following stroke.

Objective: To describe a case of neuroleptic malignant syndrome associated with risperidone., Clinical Picture: An elderly patient with bipolar affective disorder presented with neuroleptic malignant syndrome and relapse of hypomania after commencing risperidone., Treatment: Risperidone was ceased and the patient monitored closely., Outcome: The symptoms of neuroleptic malignant syndrome were resolved., Conclusion: To our knowledge this is the first such case reported, and suggests that risperidone, like other neuroleptics, is associated with neuroleptic malignant syndrome.

The objective of this study was to describe the clinical characteristics of minor depression after stroke and to compare this disorder with poststroke major depression and the nondepressed state. Ninety-four stroke inpatients were examined 8 weeks after stroke and reexamined 15 months later. Twenty-one (22%) of the 94 patients suffered from minor depression, 14 (15%) suffered from major depression, and 59 (63%) were not depressed. Minor depressed patients were twice as symptomatic as nondepressed patients but were only half as symptomatic as major depressed patients. Minor depressed patients were more likely than nondepressed patients to have a previous history of stroke and were more physically disabled. They were less likely than major depressed patients to have a family history of affective disorder. Depression symptom severity was associated with greater physical disability among minor but not major depressed patients. Fewer minor than major depressed patients were depressed at 15 months. These findings suggest that poststroke major and minor depression may be different depressive syndromes. Some cases of minor depression may be construed as an adjustment reaction to stroke disability.