Growth resistance and resilience of mixed silver fir and Norway spruce forests in central Europe: Contrasting responses to mild and severe droughts

Extreme droughts are expected to increase in frequency and severity in many regions of the world, threatening multiple ecosystem services provided by forests. Effective strategies to adapt forests to such droughts require comprehensive information on the effects and importance of the factors influencing forest resistance and resilience. We used a unique combination of inventory and dendrochronological data from a long-term (>30 years) silvicultural experiment in mixed silver fir and Norway spruce mountain forests along a temperature and precipitation gradient in southwestern Germany. We aimed at examining the mechanisms and forest stand characteristics underpinning the resistance and resilience to past mild and severe droughts. We found that (i) fir benefited from mild droughts and showed higher resistance (i.e., lower growth loss during drought) and resilience (i.e., faster return to pre-drought growth levels) than spruce to all droughts; (ii) species identity determined mild drought responses while species interactions and management-related factors strongly influenced the responses to severe droughts; (iii) intraspecific and interspecific interactions had contrasting effects on the two species, with spruce being less resistant to severe droughts when exposed to interaction with fir and beech; (iv) higher values of residual stand basal area following thinning were associated with lower resistance and resilience to severe droughts; and (v) larger trees were resilient to mild drought events but highly vulnerable to severe droughts. Our study provides an analytical approach for examining the effects of different factors on individual tree- and stand-level drought response. The forests investigated here were to a certain extent resilient to mild droughts, and even benefited from such conditions, but were strongly affected by severe droughts. Lastly, negative effects of severe droughts can be reduced through modifying species composition, tree size distribution and stand density in mixed silver fir-Norway spruce forests.

Miller-Fisher syndrome after COVID-19: neurochemical markers as an early sign of nervous system involvement

Miller-Fisher syndrome (MFS) is classified as a variant of Guillain-Barré syndrome (GBS), accounting for 5%-25% of all GBS cases. Since the coronavirus disease-2019 (COVID-19) outbreak, increasing evidence has been reported of the neurological manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, affecting both the central and peripheral nervous system. Here we report the clinical course, detailed cerebrospinal fluid (CSF) profile including CSF/blood antibody status, and neurochemical characteristics of a patient with a typical clinical presentation of MFS after a positive SARS-CoV-2 infection test.

Competing magnetic phases and fluctuation-driven scalar spin chirality in the kagome metal YMn6Sn6

Identification, understanding, and manipulation of novel magnetic textures are essential for the discovery of new quantum materials for future spin-based electronic devices. In particular, materials that manifest a large response to external stimuli such as a magnetic field are subject to intense investigation. Here, we study the kagome-net magnet YMn₆Sn₆ by magnetometry, transport, and neutron diffraction measurements combined with first-principles calculations. We identify a number of nontrivial magnetic phases, explain their microscopic nature, and demonstrate that one of them hosts a large topological Hall effect (THE). We propose a previously unidentified fluctuation-driven mechanism, which leads to the THE at elevated temperatures. This interesting physics comes from parametrically frustrated interplanar exchange interactions that trigger strong magnetic fluctuations. Our results pave a path to chiral spin textures, promising for novel spintronics.

Retour d’expérience des transferts en HéliSmur de patients Covid-19

L’augmentation du nombre d’hospitalisations en réanimation de patients graves atteints de la Covid-19 a nécessité le transfert d’un certain nombre d’entre eux vers des régions moins touchées que le Grand Est et l’Île-de-France afin de ne pas dégrader la qualité des soins. Les HéliSmur ont fait partie intégrante du dispositif d’évacuation de ces patients. Utilisés au quotidien, ils ont confirmé leur utilisation en cas de crise où la problématique des élongations est une difficulté. Cependant, le recours aux HéliSmur a nécessité une adaptation de tous à de nouvelles modalités opérationnelles. Le transport de patients critiques, le port d’un équipement de protection individuelle par l’équipe médicale et les membres d’équipage ainsi que les procédures renforcées de bionettoyage ont impacté les temps d’intervention mais aussi la charge mentale des personnes à bord. La mise en place d’équipes médicales dédiées et rompues aux transferts héliportés a permis d’optimiser la prise en charge complexe de ces patients tant sur le plan médical qu’aéronautique. Nous présentons notre retour d’expérience des transferts en HéliSmur que nous avons réalisés au départ de la région francilienne.

COVID-19 Neurologic Complication with CNS Vasculitis-Like Pattern

Coronavirus disease 2019 (COVID-19) is a viral infection caused by the Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2), which spreads rapidly from person to person and manifests in most symptomatic patients as a respiratory illness, similar to prior SARS viruses. Neurologic manifestations of COVID-19 are uncommon; those so far reported include encephalopathy, stroke from large-vessel occlusion, and polyneuropathy. We report a unique neurologic complication of COVID-19 in a patient who had extensive cerebral small-vessel ischemic lesions resembling cerebral vasculitis in a characteristic combined imaging pattern of ischemia, hemorrhage, and punctuate postcontrast enhancement. Also, a characteristic lower extremity skin rash was present in our patient. Our observation lends support to the increasingly suspected mechanism of "endotheliitis" associated with this novel coronavirus.

The MuseLearn Platform: Personalized Content for Museum Visitors Assisted by Vision-Based Recognition and 3D Pose Estimation of Exhibits

MuseLearn is a platform that enhances the presentation of the exhibits of a museum with multimedia-rich content that is adapted and recommended for certain visitor profiles and playbacks on their mobile devices. The platform consists mainly of a content management system that stores and prepares multimedia material for the presentation of exhibits; a recommender system that monitors objectively the visitor’s behavior so that it can further adapt the content to their needs; and a pose estimation system that identifies an exhibit and links it to the additional content that is prepared for it. We present the systems and the initial results for a selected set of exhibits in Herakleidon Museum, a museum holding temporary exhibitions mainly about ancient Greek technology. The initial evaluation that we presented is encouraging for all systems. Thus, the plan is to use the developed systems for all museum exhibits as well as to enhance their functionality.

Effectiveness of antibacterial prophylaxis in children with acute leukemia: A report from a single institution over a 20-year period

BACKGROUND

Infection is the major cause of treatment-related mortality in childhood acute leukemia, mainly due to bacterial translocation across the intestinal mucosa. Only a few studies have reported the impact of different antibacterial prophylaxis treatments on digestive tract flora and infection-related mortality.

PROCEDURES

We performed a retrospective analysis of two different digestive tract decontamination modalities (selective or total digestive decontamination) in a large single-center series of 323 children during the induction treatment of acute leukemia between January 1995 and December 2014. We examined the impact of antibiotic prophylaxis and food regimen (sterile or selected) on the digestive tract flora during the period of antibacterial prophylaxis, on the frequency of bacteremia, and on antibiotic sensitivity.

RESULTS

Only one Gram-negative (Klebsiella pneumonia) translocation occurred in the SDD group. No infection-related death occurred. Extended-spectrum beta-lactamase (ESBL) bacteria were observed in seven of 170 (4%) patients in the SDD group. The faecal-flora total suppression and faecal-flora Gram-negative bacilli suppression was 67 and 77%, respectively, in the TDD group with sterile food, 0 and 58%, respectively, in the SDD group with sterile food, and 6 and 63%, respectively, in the SDD group with selective food.

CONCLUSIONS

This study gives a rationale not to use antibacterial prophylaxis systematically in children who receive induction treatment for acute leukemia; additionally, antibiotics should only be used in case of stool contamination by highly pathogenic bacteria with a high potential of translocation.

Perfusion magnetic resonance imaging in pediatric brain tumors

PURPOSE

The use of DSC-MR imaging in pediatric neuroradiology is gradually growing. However, the number of studies listed in the literature remains limited. We propose to assess the perfusion and permeability parameters in pediatric brain tumor grading.

METHODS

Thirty children with a brain tumor having benefited from a DSC-MR perfusion sequence have been retrospectively explored. Relative CBF and CBV were computed on the ROI with the largest lesion coverage. Assessment of the lesion's permeability was also performed through the semi-quantitative PSR parameter and the K2 model-based parameter on the whole-lesion ROI and a reduced ROI drawn on the permeability maps. A statistical comparison of high- and low-grade groups (HG, LG) as well as a ROC analysis was performed on the histogram-based parameters.

RESULTS

Our results showed a statistically significant difference between LG and HG groups for mean rCBV (p < 10^-3), rCBF (p < 10^-3), and for PSR (p = 0.03) but not for the K2 factor (p = 0.5). However, the ratio K2/PSR was shown to be a strong discriminating factor between the two groups of lesions (p < 10^-3). For rCBV and rCBF indicators, high values of ROC AUC were obtained (> 0.9) and mean value thresholds were observed at 1.07 and 1.03, respectively. For K2/PSR in the reduced area, AUC was also superior to 0.9.

CONCLUSIONS

The implementation of a dynamic T2* perfusion sequence provided reliable results using an objective whole-lesion ROI. Perfusion parameters as well as a new permeability indicator could efficiently discriminate high-grade from low-grade lesions in the pediatric population.

Three-dimensional computed tomography angiography of the pulmonary veins and their anatomical variations: involvement in video-assisted thoracoscopic surgery-lobectomy for lung cancer

BACKGROUND

Identification and section of pulmonary veins are an essential part of anatomical pulmonary resections. Intraoperative misunderstandings of pulmonary venous anatomy can lead to serious complications such as bleeding and delayed lung infarction or necrosis. We evaluated principally the rate of pulmonary veno-us anatomical variations, and secondarily the reliability and clinical outcomes of a preoperative morphological analysis.

MATERIALS AND METHODS

Between November 2012 and October 2013, we studied 100 consecutive patients with highly suspected or diagnosed stage I-II primitive lung cancer lesion. The surgical procedure initially retained was video-assisted thoracoscopic surgery (VATS) pulmonary resections and we studied preoperatively the proximal pulmonary venous anatomy using 64 channels multi- -detector computed tomography (CT)-scan angiography to describe the venous anatomical variations.

RESULTS

There were 65 men and 35 women with a mean age of 63 years. A pulmonary venous anatomical variation was present in 36 (36%) patients, and right-sided anatomical variations were more frequent than on left-sided ones (25% vs. 11%). The most frequent variation encountered on the right side was the existence of three separate pulmonary veins (16%), and on the left side a single pulmonary vein (8%). Surgical conversion occurred in 21% and we didn't experience a pulmonary venous lesion (0%) or a post-operative lung infarction (0%).

CONCLUSIONS

We described pulmonary venous anatomical variations and their frequency. Anatomical variations exist and preoperative assessment of pulmo-nary venous anatomy using CT scan is a useful tool in VATS lobectomy to avoid unnecessary extension of pulmonary resections or iatrogenic complications in lung cancer surgery.

Polymorphism of Metallic Sodium under Nanoconfinement

(23)Na NMR studies of sodium nanoparticles confined to porous glass with the 3.5 nm mean pore size were carried out. The emergence of the second component of the NMR line was observed below 240 K that evidences the occurrence of another modification of metallic sodium. The phase transition temperature is much higher than the martensite transformation temperature in bulk sodium.

Unusual course of the aberrant right hepatic artery running through the pancreatic parenchyma during modified Frey's procedure

We report a variation of an aberrant right hepatic artery arising from the superior mesenteric artery and crossing into pancreatic head without other hepatic artery substitution. The variant was discovered during radiological examinations in a patient with symptomatic chronic pancreatitis requiring Frey's procedure with reinsertion of the common bile duct into the pancreatic head. An aberrant right hepatic artery arising from the superior mesenteric artery is present in 10 to 20% of case and its course is usually retro-pancreatic. The course of this artery into the pancreatic head is uncommon and can be present up to 10% in case of ARHA. Knowledge of an aberrant right hepatic artery crossing into the pancreatic head is important before pancreatic surgery in order to avoid surgical complications, especially for liver necrosis.

Protonenspinrelaxation von Benzol an Silikageloberflächen

Using spin-echo-techniques the temperature dependence of the proton magnetic relaxation times T1 and T2 of adsorbed benzene has been measured in the interval between +70 °C and —140 °C. Normal benzene C6H6 and mixtures of benzene and C6D6 e were adsorbed on two sorts of silicagels which have been described elsewhere 4,9.

The effective nuclear magnetic relaxation rates of adsorbed benzene are given by four contributions: the intramolecular proton-proton interaction, the interaction between benzene protons and paramagnetic impurities of the adsorbents, the interaction between benzene protons and hydroxyl protons on the silicagel surface, and the intermolecular interaction between benzene protons. These proton relaxation mechanisms depend differently on the H/D-ratio in C6H6—C6D6 mixtures (see section 4.1).

The temperature dependence of the contributions 1/T1 intra and 1/T2 intra due to intramolecular proton-proton interaction suggests an anisotropic rotation of benzene molecules on the gel used. Furthermore, the existence of three different regions for the adsorbed benzene molecules has been inferred (see sections 4.2 and 5).

A novel handheld fluorescent microarray reader for point-of-care diagnostic

A novel handheld optical sensor for quantification of fluorescent microarrays, the so-called portMD-113 has been developed. On the surface of a planar waveguide, the spots of different fluorescently labeled biological complexes are excited by the evanescent field of the guided light. The emitted fluorescence signals of the spots are independently and simultaneously detected applying our system, which consists of a pinehole array, a microlens array, an interference filter and a detector array. As it is demonstrated in comparative measurements, the detection limit of this sensor is close to that of commercial top microarray readers, e.g. of modern laser scanners, while it has remarkable and important advantages over them. Namely, the device comprises only a few low-cost, lightweight and small components without applying any moving or energy-intensive elements, which results in turn in a commercially competitive, handheld and compact design and in the possibility to be supplied simply by a battery or a personal computer. These advantageous properties open prospects e.g. for point-of-care medical checks, as well.

Roles of heat shock factor 1 and 2 in response to proteasome inhibition: consequence on p53 stability

A single heat shock factor (HSF), mediating the heat shock response, exists from yeast to Drosophila, whereas several related HSFs have been found in mammals. This raises the question of the specific or redundant functions of the different members of the HSF family and in particular of HSF1 and HSF2, which are both ubiquitously expressed. Using immortalized mouse embryonic fibroblasts (iMEFs) derived from wild-type, Hsf1(-/-), Hsf2(-/-) or double-mutant mice, we observed the distinctive behaviors of these mutants with respect to proteasome inhibition. This proteotoxic stress reduces to the same extent the viability of Hsf1(-/-)- and Hsf2(-/-)-deficient cells, but through different underlying mechanisms. Contrary to Hsf2(-/-) cells, Hsf1(-/-) cells are unable to induce pro-survival heat shock protein expression. Conversely, proteasome activity is lower in Hsf2(-/-) cells and the expression of some proteasome subunits, such as Psmb5 and gankyrin, is decreased. As gankyrin is an oncoprotein involved in p53 degradation, we analyzed the status of p53 in HSF-deficient iMEFs and observed that it was strongly stabilized in Hsf2(-/-) cells. This study points a new role for HSF2 in the regulation of protein degradation and suggests that pan-HSF inhibitors could be valuable tools to reduce chemoresistance to proteasome inhibition observed in cancer therapy.

Sequential interplay between BAG6 and HSP70 upon heat shock

BAG6/Scythe/Bat3 is a cochaperone of the heat shock protein HSP70 and is involved in various developmental processes, cellular stress and viability. BAG6 interferes with the protein-refolding activity of HSP70 but its precise involvement in proteotoxic stresses remains unknown. We show that BAG6 is required for the accumulation of HSP70 upon heat shock and that conversely, once accumulated, HSP70 leads to the massive and CHIP-independent degradation of BAG6 through the ubiquitin-proteasome system. These reciprocal influences between BAG6 and HSP70 upon heat shock suggest that BAG6 is a central regulator of the cellular content of HSP70. The HSP70-driven degradation of BAG6, following the BAG6-dependent accumulation of HSP70, could allow the protein-refolding activity of HSP70 and limit the extent of its induction.

Phase transitions in K(1-x)Na(x)NO(3) embedded into molecular sieves

Dielectric studies of molecular sieves MCM-41 filled with K(1-x)Na(x)NO(3) salts (x = 0, 0.05 and 0.10) were carried out and compared with results obtained for their bulk counterparts. The regular increase upon warming of the temperature of the reconstructive phase transition from phase II to phase I with decreasing pore sizes was observed for all x. A thermodynamic model for shifts of reconstructive phase transitions was suggested. Ferroelectric phase III was shown to occur upon cooling in bulk binary salts and for all x in confined geometry under the thermal conditions when phase III does not arise in bulk KNO(3). Ferroelectricity persisted below room temperature in the bulk binary salt with x = 0.10.