A new Middle Pleistocene interglacial sequence from Måløv, Sjælland, Denmark

Interglacial deposits in Denmark have traditionally been referred to the Cromerian complex (Hareskovian), Holsteinian or Eemian stages. However, based on studies of sediment cores from the deep sea many more than three Quaternary interglacials have been documented, and in other parts of north-western Europe it is becoming increasingly clear that the on-shore Quaternary sequences are much more complex than previously believed. Interglacial deposits are characterised by plant and animal remains indicating longer periods with climatic conditions similar to or warmer than today, whereas interstadial deposits were formed during shorter time spans and usually contain remains of relatively cold-adapted, arctic or sub-arctic species. Interglacial and interstadial deposits can be dated more or less precisely, and thus provide information about the relative age of glacial deposits

Systematic review and narrative synthesis of surgeons’ perception of postoperative outcomes and risk

Background The accuracy with which surgeons can predict outcomes following surgery has not been explored in a systematic way. The aim of this review was to determine how accurately a surgeon's ‘gut feeling’ or perception of risk correlates with patient outcomes and available risk scoring systems. Methods A systematic review was undertaken in accordance with PRISMA guidelines. A narrative synthesis was performed in accordance with the Guidance on the Conduct of Narrative Synthesis In Systematic Reviews. Studies comparing surgeons' preoperative or postoperative assessment of patient outcomes were included. Studies that made comparisons with risk scoring tools were also included. Outcomes evaluated were postoperative mortality, general and operation‐specific morbidity and long‐term outcomes. Results Twenty‐seven studies comprising 20 898 patients undergoing general, gastrointestinal, cardiothoracic, orthopaedic, vascular, urology, endocrine and neurosurgical operations were included. Surgeons consistently overpredicted mortality rates and were outperformed by existing risk scoring tools in six of seven studies comparing area under receiver operating characteristic (ROC) curves (AUC). Surgeons' prediction of general morbidity was good, and was equivalent to, or better than, pre‐existing risk prediction models. Long‐term outcomes were poorly predicted by surgeons, with AUC values ranging from 0·51 to 0·75. Four of five studies found postoperative risk estimates to be more accurate than those made before surgery. Conclusion Surgeons consistently overestimate mortality risk and are outperformed by pre‐existing tools; prediction of longer‐term outcomes is also poor. Surgeons should consider the use of risk prediction tools when available to inform clinical decision‐making. Introduction Surgical procedures all carry associated risks. It is therefore important that surgeons are able to make accurate predictions of potential benefit and risk, including immediate mortality and morbidity, as well as long‐term outcomes, to enable balanced decision‐making and fully informed consent. Risks can also be estimated after surgery, based on additional perioperative and intraoperative data, which allows contemporary prediction of outcome. There are numerous risk prediction models that enable the surgeon to quantify risk based on measurable parameters1-5. However, there are inherent limitations in using a generalized risk prediction model, which may not include clinical data pertinent to the individual case in question, leading to variability in model accuracy6-10. As a result, risk prediction tools are generally used in tandem with the surgeon's ‘gut feeling’ of overall risk and anticipated outcome (‘clinical gestalt’). Several disparate factors influence surgeons' perception of outcome: patient factors, such as their perceived fitness, their pathology and planned procedure; setting factors, such as the experience of other members of staff; and surgeon factors, such as clinical knowledge, operative skill, previous significant surgical complications, and inclinations and attitudes11-13. Anticipating surgical risk is subject to multiple biases, which make it challenging. These include the natural tendency toward anecdotal recall and the availability heuristic (the likelihood of making a decision based on how easily the topic or examples come to mind)14, 15. Some studies16-18 support the accuracy and reproducibility of surgeons' predictions, whereas others19-22 demonstrate less favourable results. The complexity of synthesizing risk perceptions is significant and incompletely understood23, 24. The accuracy of surgeons' prediction has not been explored previously in a systematic manner. The aim of this review was thus to determine, from the available evidence, whether a surgeon's gut feeling or perception of risk correlates with postoperative outcomes, and to compare this prediction with currently available risk scoring systems, where available. Methods This systematic review was undertaken in accordance with the PRISMA guidelines25, 26. MEDLINE (via PubMed), Embase, the Cochrane Library Database, and the Cochrane Collaboration Central Register of Controlled Clinical Trials were searched with no date or language restrictions, with the last search date on 9 July 2018. The search term used was (‘Surgeons’[Mesh] OR ‘General Surgery/manpower*’ [MeSH]) AND (‘perception’ OR ‘intuition’ OR ‘predict*’ OR ‘decision making’ [mesh]). There was no restriction on publication type. This search was complemented by an exhaustive review of the bibliography of key articles, and also by using the Related Articles function in PubMed of included papers. Results were restricted to human research published in English. Inclusion and exclusion criteria All studies of patients undergoing surgery in which a preoperative or postoperative surgeon assessment (or proxy assessment) of a postoperative outcome was performed were included. This included articles that reported general risk (such as mortality) or a surgery‐specific risk (for example anastomotic leakage). Studies that made comparisons with established risk scoring tools were also included. Papers or abstracts in English, or non‐English papers with an English abstract, were included. Papers describing the risk assessment of ‘theoretical’ cases, or patient vignettes in a situation distant from clinical practice (such as a conference), were excluded, as were studies in which surgeons' assessment of risk was compared with an established risk scoring tool, without data on actual patient outcome. Data extraction and assessment of study quality Three authors independently extracted data and assessed the methodological quality of the studies, with all data extraction independently checked by the senior author. The following baseline data were extracted from each study: first author, year of publication, data collection period, geographical location, study design and type (single or multiple centres, number of surgeons involved in risk estimation, whether consecutive patients were enrolled), surgical specialty, whether other risk scoring systems were used for comparison and, if so, whether the assessor was blinded to this result. Data extracted regarding the assessment of risk included: risk outcome assessed; timing of risk estimation (preoperative or postoperative); type of risk assessment by surgeons (qualitative, quantitative, continuous scale such as a visual analogue scale (VAS), or composite score); absolute value of risk event predicted by surgeon and by scoring system; absolute value of risk occurrence rate; summary data on outcome reported, including area under the curve (AUC) of receiver operating characteristic (ROC) curves, observed : expected (O : E) or predicted : observed (P : O) ratios, or any other summary data. When data were available, AUCs were extracted with their 95 per cent confidence intervals. AUCs greater than 0·9 were considered as indicating high performance, 0·7–0·9 as moderate performance, 0·5–0·7 as low performance, and less than 0·5 as indicating risk assessment no better than chance alone27, 28. Risk predictions made by pre‐existing tools, such as the Physiological and Operative Severity Score for the enumeration of Mortality and morbidity (POSSUM)1, Portsmouth‐POSSUM (P‐POSSUM)4 or Continuous Improvement in Cardiac Surgery Program (CICSP)5, were compared with outcome when given. Internal prediction models, where authors would derive significant predictive co‐variables from their data set and assess the accuracy of these co‐variables within the same data set, were not evaluated as they lacked validity. Study quality was assessed using the Newcastle–Ottawa (NO) score29, 30. The NO score assigns points based on: the quality of patient selection (maximum 4 points); comparability of the cohort (maximum 2 points); and outcome assessment (maximum 3 points). Studies that scored 6 points or more were considered to be of higher quality. Outcome measures The following outcome measures were defined a priori and refined during data extraction: postoperative mortality (usually defined as 30 days after surgery); postoperative general morbidity (usually defined as 30 days after surgery); postoperative procedure‐specific morbidity; and long‐term outcome (typically operation‐specific). Further comparative analyses of outcomes included comparison of preoperative and postoperative predictions, and of predictions made by consultants and surgical trainees. Narrative synthesis Given the marked heterogeneity in study design, patient population included, method of assessing risk and outcomes assessed, meta‐analysis was deemed not appropriate. A narrative synthesis was therefore performed according to the Guidance on the Conduct of Narrative Synthesis In Systematic Reviews31. Three authors systematically summarized each article using bullet points to document key aspects of each study, focusing particularly on methods used and results obtained. The validity and certainty of the results were noted (whether appropriate statistical comparisons were used and, if so, their effect size and significance). The senior author identified and grouped common themes, divided larger themes into subthemes, tabulated a combined summary of the paper, and synthesized a common rubric for each theme. Consolidated reviewers' comments can be found in Table S1 (supporting information). Results A total of 584 articles were identified from the literature search, of which 48 were retrieved for evaluation. Papers were excluded on the basis of being duplicates (1) and being irrelevant based on the title (497) and abstract (38) (Fig. 1). Twenty‐seven studies16-24, 32-49 comprising 20 898 patients met the inclusion criteria and were included in the narrative synthesis (Appendix S1, supporting information)

Enregistrement des biocénoses de la première moitié de l'Holocène en contexte tufacé à Saint-Germain-le-Vasson (Calvados)

À Saint-Germain-le-Vasson (Calvados) l'accumulation d'un tuf de source sur 10 mètres d'épaisseur reposant sur des dépôts organiques, a permis une étude paléoenvironnementale à haute résolution de la première moitié de l'Holocène (9700 ± 90 à 4213 ± 77 BP) par l'analyse des cortèges malacologiques et polliniques répartis sur quatre séquences. La succession des malacocénoses, particulièrement riches et bien conservées, montre, après une première phase de prairie marécageuse, l'apparition puis le développement régulier du couvert forestier. Plusieurs espèces, repérées dans d'autres séries tufacées d'Europe du Nord-Ouest pour leur intérêt biostratigraphique et biogéographique, sont présentes à Saint-Germain-le-Vasson. La stratigraphie des tufs présentant souvent une forte variabilité latérale, les occurrences de ces espèces repères ont été utilisées pour proposer des corrélations entre les différents profils observés. Celles-ci ont amené à identifier des hiatus au sommet et à la base du dépôt sur certains des carottages étudiés. L'analyse des cortèges polliniques dans l'argile organique, la tourbe et le début de la formation tufacée qui forment la base du dépôt, ainsi que les datations radiocarbone, ont permis de confirmer les discontinuités mises en évidence par les données malacologiques, de conforter les corrélations établies sur la base du développement des successions malacologiques et de reconnaître un autre hiatus au début de l'enregistrement sédimentaire.Results are presented of a detailed palaeoenvironmental study from a 10m thick tufa of early Holocene age (9700 ± 90 to 4213 ± 77 yr BP) at Saint-Germain-le-Vasson, Normandy. The work is based on malacological and palynological analyses from four profiles. Malacofaunas are rich and well preserved and show an early phase of marshy grassland assemblages followed by a sequence of shade-demanding taxa, reflecting the encroachment of woodland. Several species of biostratigraphical and biogeographical significance are present, allowing correlation between the studied profiles. Stratigraphical hiatus have been identified at both the base and the top of the deposit. Pollen analysis (and radiocarbon dates) of the basal clay, the black peat and lowermost tufa provides additional evidence for stratigraphical discontinuities and supports correlations based on malacological data. It has also allowed the identification another hiatus at the beginning of the sequence

Late-glacial and Early Holocene climate and environment from stable isotopes in Welsh tufa

The Caerwys tufa in North Wales (UK) contains basal deposits thought to represent carbonate precipitation during the Late-glacial interstadial. These deposits are used to test whether stable isotope data record all or part of a warming-cooling-warming trend through the transition of the Late-glacial interstadial, Younger Dryas stadial and early Holocene. The d18O values and molluscan abundance data suggest that deposition of the Late-glacial tufa occurred mainly during a relatively warm period (? GL-1c or 1e) followed by cooling, the latter likely to be the transition into the Younger Dryas stadial. Tufa deposition is not recorded in the coldest part of the stadial: it is replaced by a sandy horizon. d13C values around -8.5‰ in the basal Late-glacial interstadial tufas show there was a significant influence from isotopically light soil-zone CO2, consistent with development of birch scrub and woodland further south in North Wales. During climatic cooling into the Younger Dryas stadial a 1‰ decrease in tufa d13C is interpreted to represent decreasing phytoplankton photosynthetic activity in pools causing less isotopic enrichment of the tufa d13C.  In the (pre-9000 cal. years BP) early Holocene tufas at Caerwys, palaeo-water temperatures calculated from d18O in tufa calcite and from shell carbonate of Lymnaea peregra agree well and suggest summer water temperatures in the range 13 to 16.5°C.  d13C data from these early Holocene pool-micrite tufas demonstrate that phytoplanktonic photosynthetic activity within the water column resumed under the warmer conditions causing isotopic enrichment of the tufa d13C values.Le tuf de Caerwys situé au nord du Pays de Galles (Grande-Bretagne) contient, à sa base, des dépôts à précipitations carbonatées, attribués à l'interstade du Tardiglaciaire. Ces dépôts sont utilisés pour tester la validité des isotopes stables dans l'enregistrement d'une séquence de température chaud-froid-chaud au cours de la transition Interstade du Tardiglaciaire-Dryas récent- début Holocène. Les valeurs de d18O  ainsi que la courbe d'abondance des malacofaunes indiquent que le tuf tardiglaciaire s'est déposé au cours d'une phase tempérée (GL-1c ou 1e ?) suivie par un refroidissement qui pourrait correspondre à la transition vers le Dryas récent. Au cours de la phase la plus froide de cet épisode stadiaire la formation du tuf cesse et la sédimentation devient sableuse. Les valeurs de d13C  qui se placent autour de -8.5‰ dans le tuf interstadiaire de base montrent une influence significative de la zone CO2 du sol isotopiquement faible qui est cohérente avec l'extension vers le sud de forêts de bouleaux dans la partie nord du Pays de Galles. Pendant le refroidissement du Dryas récent, la baisse de 1‰ du d13C du tuf est interprétée comme la représentation de la diminution de l'activité photosynthétique du phytoplancton dans les mares qui est la cause d'un enrichissement isotopique plus faible du d13C du tuf. Au sein des tout premiers niveaux de tuf holocènes (pré-9000 cal.an BP) à Caerwys, les paléo-températures de l'eau calculées à partir du d18O de la calcite du tuf et des carbonates des coquilles de Lymnaea peregra sont en bon accord et suggèrent des estimations des températures estivales de l'eau situées entre 13 et 16.5°C.  Les données de d13C  obtenues dans ces tufs de mare-micrite du début de l'Holocène démontrent que l'activité photosynthétique du phytoplancton à l'intérieur de la colonne d'eau reprend quand les conditions sont plus chaudes et provoquent un enrichissement isotopique des valuers de d13C du tuf

Molecular fossils as a tool for tracking Holocene sea-level change in the Loch of Stenness, Orkney

Sediments deposited in the Loch of Stenness (Orkney Islands, Scotland) during the Holocene transgression, previously dated to between ~5939–5612 bp, were analysed for molecular fossils – lipids and chlorophyll pigments from primary producers – that complement conventional microfossil and lithological approaches for studying past sea-level change. While microfossil and lithological studies identified a transgression between 102 and 81 cm core depth, key molecular fossils fluctuate in occurrence and concentration between 118 and 85 cm, suggesting an earlier start to the transgression. Terrestrial lipid concentrations decreased and algal-derived, short-chain, n-alkanoic acid concentrations increased at 118 cm, indicating a disruption of the freshwater lake conditions associated with the early stages of the marine transgression. The lipid and pigment analyses provided information that complements and extends that from microfossil analysis, presenting a more complete record of Holocene sea-level changes and local vegetation changes in the Loch of Stenness. The isostatic stability of Stenness during the Holocene points towards other factors to explain the transgression, such as regional factors and/or melting of the Antarctic ice sheet (which occurred up to 3 ka)

Redescription of Acmella tersa (Benson, 1853), the Type Species of Acmella W.T. Blanford, 1869 (Gastropoda: Assimineidae), from Meghalaya, Northeast India

The type species of the assimineid genus Acmella W.T. Blanford, 1869 is Cyclostoma tersum Benson, 1853, originally described from ‘Musmai’ [Mawsmai], Meghalaya, Northeast India. No specimens from Benson’s type series can be traced, and contemporary shells collected from the type locality in museum collections are extremely worn. It has therefore been impossible to examine shell microsculpture, an important taxonomic character in the diagnosis of species of Assimineidae, using museum specimens. In order to provide better diagnostic characters for the genus Acmella, we redescribe and illustrate Acmella tersa from newly collected specimens, one of which is designated as the neotype. We also provide a list of all known species attributed to Acmella

An aminostratigraphy for the British Quaternary based on Bithynia opercula

Aminostratigraphies of Quaternary non-marine deposits in Europe have been previously based on the racemization of a single amino acid in aragonitic shells from land and freshwater molluscs. The value of analysing multiple amino acids from the opercula of the freshwater gastropod Bithynia, which are composed of calcite, has been demonstrated. The protocol used for the isolation of intra-crystalline proteins from shells has been applied to these calcitic opercula, which have been shown to more closely approximate a closed system for indigenous protein residues. Original amino acids are even preserved in bithyniid opercula from the Eocene, showing persistence of indigenous organics for over 30 million years. Geochronological data from opercula are superior to those from shells in two respects: first, in showing less natural variability, and second, in the far better preservation of the intra-crystalline proteins, possibly resulting from the greater stability of calcite. These features allow greater temporal resolution and an extension of the dating range beyond the early Middle Pleistocene. Here we provide full details of the analyses for 480 samples from 100 horizons (75 sites), ranging from Late Pliocene to modern. These show that the dating technique is applicable to the entire Quaternary. Data are provided from all the stratotypes from British stages to have yielded opercula, which are shown to be clearly separable using this revised method. Further checks on the data are provided by reference to other type-sites for different stages (including some not formally defined). Additional tests are provided by sites with independent geochronology, or which can be associated with a terrace stratigraphy or biostratigraphy. This new aminostratigraphy for the non-marine Quaternary deposits of southern Britain provides a framework for understanding the regional geological and archaeological record. Comparison with reference to sites yielding independent geochronology, in combination with other lines of evidence, allows tentative correlation with the marine oxygen isotope record

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Reductions in co-contraction following neuromuscular re-education in people with knee osteoarthritis

Background Both increased knee muscle co-contraction and alterations in central pain processing have been suggested to play a role in knee osteoarthritis pain. However, current interventions do not target either of these mechanisms. The Alexander Technique provides neuromuscular re-education and may also influence anticipation of pain. This study therefore sought to investigate the potential clinical effectiveness of the AT intervention in the management of knee osteoarthritis and also to identify a possible mechanism of action. Methods A cohort of 21 participants with confirmed knee osteoarthritis were given 20 lessons of instruction in the Alexander Technique. In addition to clinical outcomes EMG data, quantifying knee muscle co-contraction and EEG data, characterising brain activity during anticipation of pain, were collected. All data were compared between baseline and post-intervention time points with a further 15-month clinical follow up. In addition, biomechanical data were collected from a healthy control group and compared with the data from the osteoarthritis subjects. Results: Following AT instruction the mean WOMAC pain score reduced by 56% from 9.6 to 4.2 (P<0.01) and this reduction was maintained at 15 month follow up. There was a clear decrease in medial co-contraction at the end of the intervention, towards the levels observed in the healthy control group, both during a pre-contact phase of gait (p<0.05) and during early stance (p<0.01). However, no changes in pain-anticipatory brain activity were observed. Interestingly, decreases in WOMAC pain were associated with reductions in medial co-contraction during the pre-contact phase of gait. Conclusions: This is the first study to investigate the potential effectiveness of an intervention aimed at increasing awareness of muscle behaviour in the clinical management of knee osteoarthritis. These data suggest a complex relationship between muscle contraction, joint loading and pain and support the idea that excessive muscle co-contraction may be a maladaptive response in this patient group. Furthermore, these data provide evidence that, if the activation of certain muscles can be reduced during gait, this may lead to positive long-term clinical outcomes. This finding challenges clinical management models of knee osteoarthritis which focus primarily on muscle strengthening