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The Mediterranean region is projected to experience severe drying trends and more extreme hydroclimate events as a consequence of anthropogenic climate change over the next century. In some places this signal may have already emerged from natural variability, but uncertainty in long-term paleoclimate reconstructions can be a significant challenge to the detection of the influence of rising CO 2 on droughts. Here we provide expanded context for recent and future hydroclimate changes with a new high-resolution (0.5 o ) spatial reconstruction of the Palmer Drought Severity Index (PDSI) using a tree-ring network that spans much of the last millennium. This network provides new perspective on the existing Old World Drought Atlas (OWDA) and allows us to characterize differences between OWDA and our reconstruction. In light of the uncertainties we identify, we also reexamine previous conclusions about the severity of recent droughts in the context of earlier centuries. We find that, in both the western Mediterranean and the Levant, recent dry periods remain the worst in at least the last 500 years, but our assessment of the significance and confidence in this finding is affected by differences in the tree-ring networks used for the reconstructions. Long millennium-length hydroclimate reconstructions in the Mediterranean do provide the opportunity to understand variability and trends in the hydroclimate of the region, but extant uncertainties arising from the existing tree-ring chronology network and methodological choices call attention to locations that require further proxy collection, chronology updates, and statistical scrutiny. [ABSTRACT FROM AUTHOR]

Corded and hyalinized endometrioid carcinoma (CHEC) typically shows low-grade features and "no specific molecular profile" (NSMP). This study aimed to perform a clinicopathological and molecular characterization of endometrial CHEC with high-grade features. Immunohistochemistry for cytokeratin AE1/AE3, e-cadherin, β-catenin, estrogen receptor, progesterone receptor, p53, p16, and mismatch repair proteins was performed. A next-generation sequencing kit was used to assess POLE, POLD1, APC, MLH1, MSH2, MSH6, PMS2, MUTYH, EPCAM, and CTNNB1. Molecular groups, i.e., POLE-mutant, mismatch repair deficient (MMRd), p53-abnormal, and NSMP, were assigned according to the TCGA classifier. Six high-grade endometrial CHECs were identified. The mean age was 57.5 years; 5/6 cases were uterine-confined. Five cases showed a diffusely and markedly atypical corded component and a MMRd or p53-abnormal signature; additional features included single-cell keratinization, necrosis, osteoid or myxoid/chondro-myxoid matrix, foci of anaplasia, and nuclear β-catenin expression. The remaining case showed a low mitotic count and a NSMP phenotype, with focal bizarre cells in an otherwise classical CH endometrioid carcinoma. All cases showed variably reduced expression of epithelial markers and hormone receptors in the corded component. No mutations were found in any of the analyzed genes. In conclusion, high-grade CHECs are a heterogeneous subset of biphasic endometrial carcinoma which show similarities and differences with classical CHEC and carcinosarcoma. These cases often show MMRd or p53-abnormal signatures. [ABSTRACT FROM AUTHOR]

Key message: An exceptionally high number of blue rings were formed within and between Scots pine trees from Estonia in 1976: a year that is well known for its outstanding summer heatwave over Western Europe, but its extreme autumnal cooling over Eastern Europe has so far been neglected in scientific literature. 'Blue rings' (BRs) are visual indicators of less lignified cell walls typically formed towards the end of a tree's growing season. Though BRs have been associated with ephemeral surface cooling, often following large volcanic eruptions, the intensity of cold spells necessary to produce BRs, as well as the consistency of their formation within and between trees still remains uncertain. Here, we report an exceptionally high BR occurrence within and between Scots pine (Pinus sylvestris L.) trees at two sites in Estonia, including the first published whole-stem analysis for BRs. Daily meteorological measurements from a nearby station allowed us to investigate the role temperature has played in BR formation since the beginning of the twentieth century. The single year in which BRs were consistently formed within and amongst most trees was 1976. While the summer of 1976 is well known for an exceptional heatwave in Northwest Europe, mean September and October temperatures were remarkably low over Eastern Europe, and 3.8 °C below the 1961–1990 mean at our sites. Our findings contribute to a better eco-physiological interpretation of BRs, and further demonstrate their ability to reveal ephemeral cooling not captured by dendrochronological ring width and latewood density measurements. [ABSTRACT FROM AUTHOR]

Herein, we present a clinicopathological and molecular analysis of four cases of endometrial carcinoma (EC) diffusely exhibiting dyshesive cells with wide eosinophilic and vacuolated cytoplasm (histiocyte-like tumor cells, HLTCs). We compared these HLTCs to similar cells found in microcystic, elongated and fragmented (MELF) pattern (n = 20) or after neoadjuvant chemotherapy (NAC) (n = 5). The four cases were endometrioid, serous, clear cell, and gastric-type; all were at FIGO stage ≥ III. HLTCs showed an epithelial Müllerian phenotype and at least focal CK20, HNF1β, and CK5/6 expression, with aberrant e-cadherin and β-catenin expression; two cases were MMR-deficient, and one was p53-abnormal; all were POLE wild type. MELF-associated and NAC-associated HLTCs showed similar morphological/immunophenotypical features. However, MELF-associated HLTCs were mainly intraglandular and inflammation-associated, did not form a distinct tumor component, and showed no relationship with lymph node metastases. In conclusion, different histotypes of EC may show a prominent HLTC component, which shows peculiar morphological/immunophenotypical features and appears associated with aggressive behavior. [ABSTRACT FROM AUTHOR]

Pancreatic cancer is characterized by abundant desmoplasia, a dense stroma composed of extra-cellular and cellular components, with cancer associated fibroblasts (CAFs) being the major cellular component. However, the tissue(s) of origin for CAFs remains controversial. Here we determine the tissue origin of pancreatic CAFs through comprehensive lineage tracing studies in mice. We find that the splanchnic mesenchyme, the fetal cell layer surrounding the endoderm from which the pancreatic epithelium originates, gives rise to the majority of resident fibroblasts in the normal pancreas. In a genetic mouse model of pancreatic cancer, resident fibroblasts expand and constitute the bulk of CAFs. Single cell RNA profiling identifies gene expression signatures that are shared among the fetal splanchnic mesenchyme, adult fibroblasts and CAFs, suggesting a persistent transcriptional program underlies splanchnic lineage differentiation. Together, this study defines the phylogeny of the mesenchymal component of the pancreas and provides insights into pancreatic morphogenesis and tumorigenesis. Cancer-associated fibroblasts (CAFs) are the main component of the stroma in pancreatic cancer, but their tissue of origin remains to be defined. Here the authors perform lineage tracing and single cell RNA sequencing in mice and suggest the splanchnic mesenchyme as the tissue of origin for CAFs. [ABSTRACT FROM AUTHOR]

Ensuring and disseminating high-quality data is crucial for central banks to adequately support monetary analysis and the related decision-making processes. In this paper, we develop a new machine learning procedure for the identification of errors in banks' supervisory reports on loans to the private sector, which are employed in the Bank of Italy's production of statistics on Monetary Financial Institutions' (MFIs) Balance Sheet Items (BSI). We model a "Revisions Adjusted–Quantile Regression Random Forest" (RA–QRRF) algorithm in which the predicted acceptance regions of the reported values are calibrated through an individual "imprecision rate" derived from the entire history of each bank's reporting errors and revisions collected by the Bank of Italy. The analysis shows that our RA-QRRF approach provides very satisfying results in terms of error detection, especially for loans to the households sector, and outperforms well-established alternative outlier detection procedures based on probit and logit models. [ABSTRACT FROM AUTHOR]

More than 200 years after von Humboldt's pioneering work on the treeline, our understanding of the cold distribution limit of upright plant growth is still incomplete. Here, we use wood anatomical techniques to estimate the degree of stem cell wall lignification in 1770 plant species from six continents. Contrary to the frequent belief that small plants are less lignified, we show that cell wall lignification in 'woody' herbs varies considerably. Although trees and shrubs always exhibit lignified cell walls in their upright stems, small plants above the treeline may contain less lignin. Our findings suggest that extremely cold growing season temperatures can reduce the ability of plants to lignify their secondary cell walls. Corroborating experimental and observational evidence, this study proposes to revisit existing theories about the thermal distribution limit of upright plant growth and to consider biochemical and biomechanical factors for explaining the global treeline position. A global survey of lignin content in plant cell walls corroborates suggestions that cold temperature limits upright tree growth. [ABSTRACT FROM AUTHOR]

The largest explosive volcanic eruption of the Common Era in terms of estimated sulphur yield to the stratosphere was identified in glaciochemical records 40 years ago, and dates to the mid-thirteenth century. Despite eventual attribution to the Samalas (Rinjani) volcano in Indonesia, the eruption date remains uncertain, and the climate response only partially understood. Seeking a more global perspective on summer surface temperature and hydroclimate change following the eruption, we present an analysis of 249 tree-ring chronologies spanning the thirteenth century and representing all continents except Antarctica. Of the 170 predominantly temperature sensitive high-frequency chronologies, the earliest hints of boreal summer cooling are the growth depressions found at sites in the western US and Canada in 1257 CE. If this response is a result of Samalas, it would be consistent with an eruption window of circa May–July 1257 CE. More widespread summer cooling across the mid-latitudes of North America and Eurasia is pronounced in 1258, while records from Scandinavia and Siberia reveal peak cooling in 1259. In contrast to the marked post-Samalas temperature response at high-elevation sites in the Northern Hemisphere, no strong hydroclimatic anomalies emerge from the 79 precipitation-sensitive chronologies. Although our findings remain spatially biased towards the western US and central Europe, and growth-climate response patterns are not always dominated by a single meteorological factor, this study offers a global proxy framework for the evaluation of paleoclimate model simulations. [ABSTRACT FROM AUTHOR]

Purpose: To investigate critical aspects and effectiveness of in vivo dosimetry (IVD) tests obtained by an electronic portal imaging device (EPID) in a multicenter and multisystem context. Materials and methods: Eight centers with three commercial systems—SoftDiso (SD, Best Medical Italy, Chianciano, Italy), Dosimetry Check (DC, Math Resolution, LCC), and PerFRACTION (PF, Sun Nuclear Corporation, SNC, Melbourne, FL)—collected IVD results for a total of 2002 patients and 32,276 tests. Data are summarized for IVD software, radiotherapy technique, and anatomical site. Every center reported the number of patients and tests analyzed, and the percentage of tests outside of the tolerance level (OTL%). OTL% was categorized as being due to incorrect patient setup, incorrect use of immobilization devices, incorrect dose computation, anatomical variations, and unknown causes. Results: The three systems use different approaches and customized alert indices, based on local protocols. For Volumetric Modulated Arc Therapy (VMAT) treatments OTL% mean values were up to 8.9% for SD, 18.0% for DC, and 16.0% for PF. Errors due to "anatomical variations" for head and neck were up to 9.0% for SD and DC and 8.0% for PF systems, while for abdomen and pelvis/prostate treatments were up to 9%, 17.0%, and 9.0% for SD, DC, and PF, respectively. The comparison among techniques gave 3% for Stereotactic Body Radiation Therapy, 7.0% (range 4.7–8.9%) for VMAT, 10.4% (range 7.0–12.2%) for Intensity Modulated Radiation Therapy, and 13.2% (range 8.8–21.0%) for 3D Conformal Radiation Therapy. Conclusion: The results obtained with different IVD software and among centers were consistent and showed an acceptable homogeneity. EPID IVD was effective in intercepting important errors. [ABSTRACT FROM AUTHOR]

Background: Celiac disease (CD) is a systemic inflammatory disease, which primarily affects the gastrointestinal tract. It has been recently demonstrated that adipose-tissue infiltration by proinflammatory immune cells causes a chronic low-grade inflammation in obese patients. Magnetic resonance imaging (MRI) has already proved to be useful in evaluation of inflammatory states. The aim of the present study was to determine whether alterations of visceral and subcutaneous adipose tissue, identified with MRI, could serve as markers of local and systemic inflammation in patients with CD. Methods: A pilot study was conducted comparing alterations in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) in CD patients vs obese patients and healthy controls. Fifty patients were enrolled and assigned to one of the following groups: Group A: 11 active CD patients; Group B: 11 CD patients in remission; Group C: 16 obese patients; Group D: 12 healthy controls. A 3-T MRI unit was used and T2-weighted TSE images of VAT and SAT were obtained in specific regions of interest. Serum cytokine concentrations (TNF-α, IL-6, adiponectin, leptin, IL-2, IFN-γ) were determined. Results: There was a significant difference in VAT T2 relaxation time between Group A and B (p < 0.001), A and D (p < 0.01), B and C (p < 0.001). There was a statistically significant difference in SAT T2 relaxation time between Group A and B (p < 0.001), A and C (p < 0.05), A and D (p < 0.001), B and C (p < 0.01). In addition, VAT/SAT T2 relaxation time ratio showed a statistically significant difference between Group A and C (p < 0.05) and between Group B and C (p < 0.01). Only TNF-α and IL-6 significantly correlated with both VAT and VAT/SAT ratio in active CD. Conclusions: MRI showed similar increased visceral inflammatory signals in patients with active CD and obese patients. However, subcutaneous inflammatory signals were higher in active CD than in all the other groups. These data show that there is a systemic inflammatory state in active CD, whereas chronic inflammation appears confined to VAT in obesity. These data were only partially confirmed by serological cytokine profiles, which showed less specificity than MRI. [ABSTRACT FROM AUTHOR]

Although wood anatomical features can provide yearly resolved climatic information at sub-seasonal resolution, the occurrence of intra-annual density fluctuations (IADFs) might be triggered by several abiotic factors under different ecological settings. Here, we use information on cambial age and tree-ring width to standardize the frequency of IADFs in European black pines from three different mountain slopes in the central Apennines (Italy). At each site, we sampled isolated 15–30-year pioneer pines above the forest limit, as well as close-grown 40–60-year planted pines at the forest limit. Mainly restricted to the latewood of both pioneer and planted trees, the occurrence of IADFs reveals a significant positive relationship with cambial age and ring width. Although the standardized IADFs are well synchronized between the planted and pioneer pines, the frequency of IADFs in narrow rings was higher in the pioneer pines. Drought conditions in July and August are responsible for the highest IADFs frequency in planted and pioneer pines, respectively. Our study underlines the value of IADFs to obtain a more nuanced understanding of the climatic drivers of wood formation at the intra-annual scale. [ABSTRACT FROM AUTHOR]

Since financial inclusion has become a policy target in many countries, properly measuring it is crucial. Usual indexes of financial inclusion include inappropriate variables and don't take into account other relevant aspects, thus misrepresenting the phenomenon. In this work we focus on the diffusion of electronic cards, generally not included in the usual indexes of financial inclusion notwithstanding they provide alternatives to usual saving practices and allow less costly transactions across larger markets and wider geographic areas. We show that, taking these instruments into account, the comparative valuation of the degree of financial inclusion between the main euro area countries changes substantially. We also employ survey data to analyze cross-country differences in the degree of financial inclusion and the distribution of multidimensional deprivations of specific sub-groups of populations. [ABSTRACT FROM AUTHOR]

The sudden interruption of recurring larch budmoth (LBM; Zeiraphera diniana or griseana Gn.) outbreaks across the European Alps after 1982 was surprising, because populations had regularly oscillated every 8–9 years for the past 1200 years or more. Although ecophysiological evidence was limited and underlying processes remained uncertain, climate change has been indicated as a possible driver of this disruption. An unexpected, recent return of LBM population peaks in 2017 and 2018 provides insight into this insect's climate sensitivity. Here, we combine meteorological and dendrochronological data to explore the influence of temperature variation and atmospheric circulation on cyclic LBM outbreaks since the early 1950s. Anomalous cold European winters, associated with a persistent negative phase of the North Atlantic Oscillation, coincide with four consecutive epidemics between 1953 and 1982, and any of three warming-induced mechanisms could explain the system's failure thereafter: (1) high egg mortality, (2) asynchrony between egg hatch and foliage growth, and (3) upward shifts of outbreak epicentres. In demonstrating that LBM populations continued to oscillate every 8–9 years at sub-outbreak levels, this study emphasizes the relevance of winter temperatures on trophic interactions between insects and their host trees, as well as the importance of separating natural from anthropogenic climate forcing on population behaviour. [ABSTRACT FROM AUTHOR]

In many countries, household debt increased from the 1990s until the global financial crisis of 2007–2008 and then stagnated with the Great Recession, the euro-area sovereign debt crisis and deleveraging. In spite of these common trends, differences in national household debt/disposable income ratios are evident. This paper studies the determinants of household debt using a dataset of 33 countries and taking into account both demand-side and supply-side factors. The econometric exercises, covering the period 1995–2016, yield the following results. First, there is a positive link between household debt and both household wealth and house price growth. Second, the quality of bankruptcy laws relates positively to household debt, whereas longer insolvency resolution times are associated with lower household debt. Third, Anglo-Saxon legal origin and Scandinavian legal origin have a stronger link with household debt than French and German legal origin. Fourth, household debt is higher in countries with social-democratic and liberal welfare models than in conservative and Eastern European welfare states. Fifth, the ratio of public debt to GDP displays a negative association with private debt. Last, the effect of saving on household debt is significant only in the years of household deleveraging, i.e. after the global financial crisis. While the effect of demand-side variables is unstable over time, supply-side variables appear to be more persistent in determining the level of household debt. [ABSTRACT FROM AUTHOR]

In vivo dosimetry (IVD) is the last step of a radiotherapy quality control program aimed to ensure that the dose delivered is in agreement with that prescribed. IVD procedures based on single detectors are time-consuming and impossible to use for the modern radiotherapy techniques, based on static or kinetic beams (modulated in intensity fluence); this means that more efficient and practical methods are highly recommended. The practical method SOFTDISO, based on the use of electronic portal image device (EPID), provides two tests (i) the R ratio between the reconstructed and the planned isocenter doses to verify an agreement within 5% and (ii) the γ-analysis of the EPID images, to verify γ% ≥ 90% and γmean ≤ 0.4. This paper reports the results of 11,357 IVD tests carried out for 823 patients treated by three-dimensional conformal radiation therapy and volumetric modulated arc therapy techniques. In particular, the dose disagreements are reported distinguishing two kinds of causes, those of (i) class 1 that includes the errors due to inadequate quality controls and (ii) the class 2, due to patient morphological changes. About the tests out of tolerance, 6% were by VMAT and 21% by 3DCRT, but taking into account the only class 1 of errors, i.e., removing the causes of class 2, only 7% of patients examined presented at least one of the three mean indexes out of tolerance. The workload for IVD on 9 patients/day per linac is about 52 min/day but recently, a new automated SOFTDISO version has been implemented to reduce the time to about 34 min/day. [ABSTRACT FROM AUTHOR]

A growing body of research suggests that a history of neglect, abuse and institutionalization can negatively affect late-adopted children's attachment representations, and that adoptive parents can play a key role in enabling adopted children to earn secure attachments. Still, only a few studies have explored the quality of caregiver-child interaction in adoptive families. The present study aimed at verifying both the concordance of attachment in adoptive dyads (mother-children and father-children) and the relationship between attachment representations and parent-child interaction. The research involved 20 adoptive families in which the child's arrival had occurred between 12 to 36 months before the assessment, and where children were aged between 4.5 and 8.5 years. Attachment was assessed through the Adult Attachment Interview for parents and through the Manchester Child Attachment Story Task for children. The emotional quality of parent-child interaction was assessed trough the Emotional Availability Scales. Our results pointed out the presence of a relation between attachment representations of late-adopted children and their adoptive mothers (75%, K = 0.50, p = .025). In addition, we found that both insecure children and mothers showed lower levels of EA than secure ones. Some explanations are presented about why, in the early post-adoption period, child attachment patterns and dyadic emotional availability seem to be arranged on different frameworks for the two parental figures. [ABSTRACT FROM AUTHOR]

Treeline position, structure, and composition are shaped by natural and anthropogenic factors. At human-disturbed treelines, it is particularly difficult to disentangle the specific role of natural and anthropogenic drivers controlling tree recruitment dynamics following land abandonment. We tested for a possible common regeneration pattern of Pinus nigra Arn. at four upper treeline ecotones in the central Apennines (Italy). The sites were selected based on (1) the occurrence of natural encroachment of P. nigra above 1600 m a.s.l., and (2) the mountain top elevation higher than 2000 m a.s.l. We assessed structure and spatiotemporal patterns of P. nigra advancing regeneration using point and surface pattern analyses. We mapped, measured, and dated 845 trees sampled on a total surface area of 336 ha. P. nigra is the only tree species expanding at high altitude and features a scattered process that started 35-40 years ago, with a maximum recruitment frequency between 1995 and 2003. Pinus regeneration appeared over-dispersed along the slope at a scale range of 12-18 m. We found spatial segregation between saplings and young trees at intermediate distances (8-17 m) and small patches of young trees distributed along the treeline ecotone. The spatial pattern of P. nigra encroachment in the central Apennines revealed a replicable model independent of treeline topography and local disturbance histories. [ABSTRACT FROM AUTHOR]

The use of exergame for balance competencies was recently explored in women affected by balance ability reduction with non-conclusive results. The aim of the study was to evaluate the efficacy of a supervised exergame performed with the Wii Fit compared to conventional exercises on balance function, quality of life, fear of fall and well-being in women with bone loss. Thirty-eight female participants aged over 65 years, with a bone loss condition, were enrolled and random allocated in the Wii group or control group. Subject enrolled in Wii group performed a balance training with a Wii Fit supervised by a physiotherapist (1 h, 2 days per week, during 8 weeks) while in control subjects performed the same amount of conventional balance exercises. Subject enrolled in experimental group showed significantly higher scores in terms of Berg Balance Scale ( p = 0.027). In SF-36 scores, a significant difference was reported for physical activity score after treatment ( p = 0.031). Fear of falling and the psychological scales were not significantly different between the two groups. In women with bone loss condition, a supervised Wii Fit training has shown better efficacy in improving balance performance with respect to conventional balance exercises. [ABSTRACT FROM AUTHOR]

The aim of this analysis is to present the methodology used to promote clinical research in a peripheral Italian department of radiotherapy (RT) and the results in terms of scientific output. Internal treatment guidelines were developed, available on the computer network of the department, containing a schematic summary 1-2 pages long of each protocol. Furthermore, a home-made database was designed to be used both as a medical record and for prospective data recording. Data entry was subjected to an 'independent check' by a second radiation oncologist. Regular meetings were organized to update all staff on the aim and conduct of the various running trials and to promote the enrollment of patients and the involvement of other specialists in clinical research. In a period of about 11 years: (1) 34 protocols for clinical trials were written and approved; (2) 7463 patients had undergone RT; of these patients, 6321 patients (85 %) were enrolled in clinical trials; (3) 345 papers/book chapters/abstracts were published; of them, 127 papers have been published in journals currently featured on PUBMED; (4) 119 scientific meetings were held. This experience shows that an independent clinical research is possible even in a non-academic and peripheral RT department. In particular, our experience suggests that personnel and resource constraints can be at least partially overcome by a strong personal and group motivation and with the adoption of flexible solutions. [ABSTRACT FROM AUTHOR]

Key message: Double-stained microsections from high altitude Pinus nigra wood cores highlighted unlignified latewood cells possibly linked to abrupt temperature reduction at the end of the growing season. More consolidated detection could increase their role in dendroecology. Abstract: Cambial activity and wood formation are influenced by environmental factors, primarily climate. During cell wall formation the lignification is mainly controlled by temperature. By staining with safranin and astra blue it is possible to distinguish cell walls richer in lignin (stained in red) from those richer in cellulose (stained in blue). Here we show an uncommon phenomenon observed in 41 transverse sections prepared for anatomical studies of young European black pine ( Pinus nigra Arnold) individuals. We detected some layers of incompletely lignified cells that appear blue in safranin-astra blue-stained sections. Growth rings showing this anatomical feature were named 'blue rings'. The aims of this preliminary study are: (i) to describe the features of this peculiar anatomical trait, (ii) to enhance its visualization, and (iii) to suggest possible drivers of its formation. First results indicate the influence of low air temperature causing a lack of lignification in latewood cells. The added values provided by the identification of 'blue rings' within tree-ring series could be (i) their possible use as pointer year, (ii) cross dating improvement, and (iii) finer assessment of tree sensitivity to environmental and climatic factors. [ABSTRACT FROM AUTHOR]

This work reports a method based on correlation functions to convert EPID transit signals into in vivo dose values at the isocenter point, D iso, of dynamic IMRT beams supplied by Varian linac. Dose reconstruction for intensity-modulated beams required significant corrections of EPID response, due to the X-ray component transmitted through multileaf collimator. The algorithm was formulated using a set of simulated IMRT beams. The beams were parameterized by means of a fluence inhomogeneity index, FI, introduced to describe the degree of beam modulation with respect to open beams. This way, all dosimetric parameters involved in D iso reconstruction algorithm, such as the correlation functions, the correction factor for EPID to phantom distance and the modulated tissue maximum ratios, were determined as a function of the FI index. Clinical IMRT beams were used to irradiate a homogeneous phantom, and for each beam, the agreement between the reconstructed dose, D iso, and the dose computed by TPS, D iso,TPS, was well within 5 %. Moreover, the average ratios, R, between the D iso, and D iso,TPS, resulted equal to 1.002 ± 0.030. Thirty-five IMRT fields of 5 different patients undergoing radiotherapy for head-neck tumors were tested and the results were displayed on a computer screen after 2 min from the end of the treatment. However, 350 in vivo tests supplied an average ratio R equal to 1.004 ± 0.040. The in vivo dosimetry procedure here presented is among the objectives of a National Project financially supported by the Istituto Nazionale di Fisica Nucleare for the development of in vivo dosimetry procedures (Piermattei et al. in Nucl Instrum Methods Phys Res B 274:42-50, 2012) connected to the Record-Verify system of the radiotherapy center. [ABSTRACT FROM AUTHOR]

practical and accurate generalized in vivo dosimetry procedure has been implemented for Siemens linacs supplying 6, 10, and 15 MV photon beams, equipped with aSi electronic portal imaging devices (EPIDs). The in vivo dosimetry method makes use of correlation ratios between EPID transit signal, s(TPR, w, L), and phantom mid-plane dose, D(TPR, w, L), as functions of phantom thickness, w, square field dimensions, L, and tissue-phantom ratio TPR. The s(TPR, w, L) and D(TPR, w, L) values were defined to be independent of the EPID sensitivity and monitor unit calibration, while their dependence on TPR was investigated to determine a set of generalized correlation ratios to be used for beams with TPR falling in the examined range. This way, other radiotherapy centers can use the method with no need to locally perform the whole set of measurements in solid water phantoms, required to implement it. Tolerance levels for 3D conformal treatments, ranging between ±5 and ±6% according to tumor type and location, were estimated for comparison purposes between reconstructed isocenter dose, D, and treatment planning system (TPS) computed dose D. Finally a dedicated software, interfaceable with record and verify (R&V) systems used in the centers, was developed to obtain in vivo dosimetry results in less than 2 min after beam delivery. [ABSTRACT FROM AUTHOR]

The transit in vivo dosimetry performed by an electronic portal imaging device (EPID) is a very practical method to check error sources in radiotherapy. Recently, the present authors have developed an in vivo dosimetry method based on correlation functions, F ( w, L), defined as the ratio between the transit signal, St ( w, L), by the EPID and the mid-plane dose, Dm ( w, L), in a solid water phantom as a function of the phantom thickness, w, and of the field dimensions, L. In particular, generalized correlation functions F ( w, L) for 6, 10 and 15 MV X-ray beams supplied by a pilot Varian linac, are here used by other three linacs operating in two centers. This way the workload, due to measurements in solid water phantom, needed to implement the in vivo dosimetry method was avoided. This article reports a feasibility study on the potentiality of this procedure for the adaptive radiotherapy of lung tumors treated by 3D conformal radiotherapy techniques. In particular, the dose reconstruction at the isocenter point Diso in the lung tumor has been used as dose-guided radiotherapy (DGRT), to detect the inter-fraction tumor anatomy variations that can require new CT scans and an adaptive plan. When a difference greater than 6% between the predicted dose by the treatment planning system (TPS), Diso,TPS and the Diso was observed, the clinical action started to detect possible anatomical lung tumor changes. Twelve over twenty patients examined presented in vivo dose discrepancies due to the tumor morphological changes during treatments, and these results were successively confirmed by new CT scans. In this work, for a patient that showed for all beams, Diso values over the tolerance level, the new CT scan was used for an adaptive plan. The lung dose volume histogram for Diso,TPS = 2 Gy per fraction suggested the adaptive plan. In particular, the lung volume included in 2 Gy increased from 350 cm3 of the original plan to 550 cm3 of the hybrid plan, while for the adaptive plan the lung volume included in 2 Gy decreased to 15 cm3. Moreover, the mean doses to the organs at risk were reduced to 70%. The results of this research show that the DGRT procedure by the Diso reconstruction, integrated with radiological imaging, was feasible for periodic investigation on morphological lung tumor changes. This feasibility study takes into account the accuracy of two algorithms based on the pencil beam and collapsed cone convolution models for dose calculations where large density inhomogeneities are present. [ABSTRACT FROM AUTHOR]

Homogeneously catalysed reactions can be ‘switched on’ by activating latent catalysts. Usually, activation is brought about by heat or an external chemical agent. However, activation of homogeneous catalysts with a mechanical trigger has not been demonstrated. Here, we introduce a general method to activate latent catalysts by mechanically breaking bonds between a metal and one of its ligands. We have found that silver(i) complexes of polymer-functionalized N-heterocyclic carbenes, which are latent organocatalysts, catalyse a transesterification reaction when exposed to ultrasound in solution. Furthermore, ultrasonic activation of a ruthenium biscarbene complex with appended polymer chains results in catalysis of olefin metathesis reactions. In each case, the catalytic activity results from ligand dissociation, brought about by transfer of mechanical forces from the polymeric substituents to the coordination bond. Mechanochemical catalyst activation has potential applications in transduction and amplification of mechanical signals, and mechanically initiated polymerizations hold promise as a novel repair mechanism in self-healing materials. [ABSTRACT FROM AUTHOR]

An amorphous silicon (a-Si) electronic portal imaging device (EPID) was implemented to perform transit in vivo dosimetry for dynamic conformal arc therapy (DCAT). A set of images was acquired for each arc irradiation using the EPID cine acquisition mode, that supplies a frame acquisition rate of one image every 1.66 s, with a monitor unit rate equal to 100 UM/min. In these conditions good signal stability, ±1% (2SD) evaluated during 3 months, signal reproducibility within ±0.8% (2SD) and linearity with dose and dose rate within ±1% (2SD) were obtained. The transit signal, St, due to the transmitted radiotherapy beam below a solid phantom, measured by the EPID cine acquisition mode was used to determine, (1) a set of correlation functions, F( w, L), defined as the ratio between St and the dose at half thickness, Dm, measured in solid water phantoms of different thicknesses, w and with square fields of side L, (2) a set of factors, f( d, L), that take into account the different x-ray scatter contribution from the phantom to the St signal as a function of the variation, d, of the air gap between the phantom and the EPID. The reconstruction of the isocenter dose, Diso, for DCAT was obtained convolving the transit signal values, obtained at different gantry angles, with the respective reconstruction factors determined by a house-made software. The method was applied to a first patient and the results show that the reconstructed Diso values can be obtained with an accuracy within ±5%. In conclusion, it was assessed that an a-Si EPID with the cine acquisition mode is suitable to perform transit in vivo dosimetry for the DCAT therapy. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via a link at the top of the paper. [ABSTRACT FROM AUTHOR]

It is generally accepted that animal heartbeat and lifespan are often inversely correlated, however, the relationship between productivity and longevity has not yet been described for trees growing under industrial and pre-industrial climates. Using 1768 annually resolved and absolutely dated ring width measurement series from living and dead conifers that grew in undisturbed, high-elevation sites in the Spanish Pyrenees and the Russian Altai over the past 2000 years, we test the hypothesis of grow fast—die young. We find maximum tree ages are significantly correlated with slow juvenile growth rates. We conclude, the interdependence between higher stem productivity, faster tree turnover, and shorter carbon residence time, reduces the capacity of forest ecosystems to store carbon under a climate warming-induced stimulation of tree growth at policy-relevant timescales. Fertilization under greenhouse warming conditions is expected to accelerate tree growth and potentially increase the biological storage of CO2. Here the authors analyse ring width measurements from 1768 conifers from the Spanish and Russian mountains and demonstrate that longevity requires slow growth rates at least in mountainous regions. [ABSTRACT FROM AUTHOR]