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We propose a conceptual model comprising a cascade of tipping points as a mechanism for past abrupt climate changes. In the model, changes in a control parameter, which could for instance be related to changes in the atmospheric circulation, induce sequential tipping of sea ice cover and the ocean's meridional overturning circulation. The ocean component, represented by the well-known Stommel box model, is shown to display so-called rate-induced tipping. Here, an abrupt resurgence of the overturning circulation is induced before a bifurcation point is reached due to the fast rate of change of the sea ice. Because of the multi-scale nature of the climate system, this type of tipping cascade may also be a risk concerning future global warming. The relatively short timescales involved make it challenging to detect these tipping points from observations. However, with our conceptual model we find that there can be a significant delay in the tipping because the system is attracted by the stable manifold of a saddle during the rate-induced transition before escaping towards the undesired state. This opens up the possibility for an early warning of the impending abrupt transition via detection of the changing linear stability in the vicinity of the saddle. To do so, we propose estimating the Jacobian from the noisy time series. This is shown to be a useful generic precursor to detect rate-induced tipping.

We investigate the freshwater budget of the Atlantic and Arctic oceans in coupled climate change simulations with the Community Earth System Model and compare a strongly eddying setup with 0.1∘ ocean grid spacing to a non-eddying 1∘ configuration typical of Coupled Model Intercomparison Project phase 6 (CMIP6) models. Details of this budget are important to understand the evolution of the Atlantic Meridional Overturning Circulation (AMOC) under climate change. We find that the slowdown of the AMOC in the year 2100 under the increasing CO2 concentrations of the Representative Concentration Pathway 8.5 (RCP8.5) scenario is almost identical between both simulations. Also, the surface freshwater fluxes are similar in their mean and trend under climate change in both simulations. While the basin-scale total freshwater transport is similar between the simulations, significant local differences exist. The high-ocean-resolution simulation exhibits significantly reduced ocean state biases, notably in the salt distribution, due to an improved circulation. Mesoscale eddies contribute considerably to the freshwater and salt transport, in particular at the boundaries of the subtropical and subpolar gyres. Both simulations start in the single equilibrium AMOC regime according to a commonly used AMOC stability indicator and evolve towards the multiple equilibrium regime under climate change, but only the high-resolution simulation enters it due to the reduced biases in the freshwater budget.

Abstract Background Pneumatosis intestinalis (PI) is a rare entity which refers to the presence of gas within the wall of the small bowel or colon which is a radiographic sign. The etiology and clinical presentation are variable. Patients with PI may present either with chronic mild non-specific symptoms or with acute abdominal pain with peritonitis. Some cases of intestinal pneumatosis have been reported as adverse events of new oncological treatments such as targeted therapies that are widely used in multiple tumors. Case presentation A 59-year-old caucasian female with radioactive iodine-refractory metastatic thyroid papillary carcinoma with BRAF V600E mutation was treated with dabrafenib and trametinib as a compassionate use. After 4 months treatment, positron emission tomography–computed tomography (PET–CT) showed PI. At the time of diagnosis, the patient was asymptomatic without signs of peritonitis. The initial treatment was conservative and no specific treatment for PI was needed. Unfortunately, after dabrafenib–trametinib withdrawal, the patient developed tumor progression with significant clinical worsening. Conclusions This case report is, in our knowledge, the first description of PI in a patient treated with dabrafenib–trametinib. Conservative treatment is feasible if there are no abdominal symptoms.

The Trajectory-Adaptive Multilevel Sampling (TAMS) is a promising method to determine probabilities of noise-induced transition in multi-stable high-dimensional dynamical systems. In this paper, we focus on two improvements of the current algorithm related to (i) the choice of the target set and (ii) the formulation of the score function. In particular, we use confidence ellipsoids determined from linearised dynamics in the choice of the target set. Furthermore, we define a score function based on empirical transition paths computed at relatively high noise levels. The suggested new TAMS method is applied to two typical problems illustrating the benefits of the modifications.

Since shifts in altitudinal range are expected in response to climate change, we explored the effect on survivorship and growth of moving populations of three Mexican pine species (Pinus devoniana, P. leiophylla and P. pseudostrobus) to higher altitude, aiming to realign the populations to projected future climates in an experimental assisted migration. Twelve populations were collected across an altitudinal gradient (1650–2520 m above sea level [asl]) in a mountainous zone in the central‐west region of the Mexican Trans‐Volcanic Belt, and were planted in common garden tests at three forest sites of different altitudes (low: 2110, medium: 2422 and upper: 2746 m asl). Climate was estimated using a spline climatic model at the seed source and test sites and also measured using in situ data loggers. Survivorship and seedling height were evaluated in the field during the second and third growing seasons. Results were analyzed using mixed models to include the effect of climatic transfer distances (difference in climate between seed source and test site). Significant differences were found in seedling growth among Pinus devoniana, P. pseudostrobus and P. leiophylla, and among populations within the former two species. These were associated primarily with climatic transfer distances of extreme temperatures (minimum temperature in the coldest month and mean temperature in the warmest month). There was a significant decrease in growth in P. devoniana when the transfer exceeded 650 m of upward altitudinal shift or a reduction of 1.5°C with transfer to colder sites. There was also a decrease of growth in P. pseudostrobus when transfer exceeded 400 m of upward altitudinal shift or 1.5°C, with a significant decrease in survivorship. Pinus leiophylla, however, exhibited similar growth at all altitudes tested, probably due to phenotypic plasticity. Although further research is required with field tests using commercial spacing and trees of older ages, the results suggest that an assisted upwards migration of 300 m in altitude, in order to approach a realignment of the populations to the climate projected for the decade centered around the year 2030, appears to be a viable strategy with which to accommodate the effects of climate change.

AIM OF THE STUDY The study is about Medicine ward inpatients in one acute hospital, before and after the implementation of the Post Acute Care Unit (PACU). Clinical parameters to be accepted in PACU and clinical and assistential needs are defined. METHODS The selection of patients relies on the absence of criteria for staying in acute hospital, as defined in the Hospital Utilization Evaluation Protocol (PRUO), and excluding patients with end stage tumors. The care burden is calculated applying the Care Complexity Score (CCS) at time of take in charge. We present data related to the first 100 consecutive patients managed in PACU, compared with those of Medicine staying obtained in 3 different days during the month antecedent the activation of PACU. RESULTS Among the in-patients in the medical ward, 17.3% can be managed in PACU. Compared to all in-patients, post acute population resulted older, with greater CCS and need of care support at discharge. The high number of deaths (24%) is due to patients with several end stage co-morbidities, which are very difficult to manage at home, with adequate tools. CONCLUSIONS Octogenarians who overcrowd acute-patient hospitals demonstrate increased care demands and may need a prolonged hospital stay to achieve clinical stabilization or functional independence after an acute event. This goal can be obtained in a specifically oriented hospital setting. The same area could also manage the end of life of patients with multiple co-morbidities, even if not with neoplastic disease.

El bastidor de la cosechadora cubana de caña de azúcar KTP-2M, es un elemento de un elevado grado de hiperestaticidady de una alta complejidad constructiva. Garantizar el diseño óptimo del mismo es un problema actual. En la presenteponencia se expone el trabajo realizado para lograr el perfeccionamiento del bastidor de la cosechadora KTP-2M,garantizando la resistencia y durabilidad de este con un gasto mínimo de materiales, para ello se utilizó el métodoextensométrico eléctrico de medición de deformaciones y se creó un modelo físico-matemático del mismo, el cual fuecalculado mediante un sistema automatizado de análisis de estructuras basado en el cálculo matricial de estas.Palabras claves: Bastidor, extensometría, strain gage, análisis, estructuras, durabilidad, frame.______________________________________________________________________AbstractThe frame of the cuban KTP-2M sugar cane harvester is an element of hight hyperstatic degree and hight constructivecomplexity. In the following report is exposed the work done to assure the improvement of the frame in the KTP-2Mharvester, warranting its strength and durability with a minimum expense of materials. The extensometer-electrical methodof measuring distortions has been used and has been created a physical-mathematical model of the structure, which wascalculated by means of an automated system of analysis based on the Finite Elements Method.Key words: Extensometer, strain gage, analysis, structures, durability, frame.

Background: Hepatitis G virus (HGV) has recently been cloned and tests for HGV RNA and envelope antibodies (anti-E2) have been developed. HGV infection is widespread among blood donors worldwide, but the clinical and serologic outcome of transfusion-associated HGV infection has not been fully characterized., Study Design and Methods: Consecutive blood donors (n = 2210) were investigated for HGV markers (RNA and anti-E2). The recipients of HGV RNA-positive blood were followed for 1 year after transfusion., Results: Forty-two blood donors (1.9%) were positive for HGV RNA. Eight recipients of HGV RNA-positive blood were retrospectively identified within 2 weeks of transfusion and prospectively followed. In four patients, the presence of anti-E2 before transfusion or an early antibody response protected them from reinfection or prevented HGV persistence, while, in the remaining four patients, transient or persistent viremia was detected shortly after exposure. None of the infected recipients had any evidence of liver disease., Conclusion: These results do not support the screening of donors to prevent transfusion-associated HGV infection.