Rapid quasi-periodic oscillations in the relativistic jet of BL Lacertae.

Blazars are active galactic nuclei (AGN) with relativistic jets whose non-thermal radiation is extremely variable on various timescales1-3. This variability seems mostly random, although some quasi-periodic oscillations (QPOs), implying systematic processes, have been reported in blazars and other AGN. QPOs with timescales of days or hours are especially rare4 in AGN and their nature is highly debated, explained by emitting plasma moving helically inside the jet5, plasma instabilities6,7 or orbital motion in an accretion disc7,8. Here we report results of intense optical and γ-ray flux monitoring of BL Lacertae (BL Lac) during a dramatic outburst in 2020 (ref. 9). BL Lac, the prototype of a subclass of blazars10, is powered by a 1.7 × 108 MSun (ref. 11) black hole in an elliptical galaxy (distance = 313 megaparsecs (ref. 12)). Our observations show QPOs of optical flux and linear polarization, and γ-ray flux, with cycles as short as approximately 13 h during the highest state of the outburst. The QPO properties match the expectations of current-driven kink instabilities6 near a recollimation shock about 5 parsecs (pc) from the black hole in the wake of an apparent superluminal feature moving down the jet. Such a kink is apparent in a microwave Very Long Baseline Array (VLBA) image.

Oral stomatitis and mTOR inhibitors: A review of current evidence in 20,915 patients.

BACKGROUND: Traditional treatment of malignancies with chemotherapeutic agents is often affected by the damage inflicted on non-cancerous cells. Toxicities of the oral cavity, such as mucositis and stomatitis, are some of the most significant and unavoidable toxicities associated with anti-cancer therapies. For such reason, in the last decades, newer targeted agents have been developed aiming to decrease the rates of side effects on healthy cells. Unfortunately, targeted anti-cancer therapies also showed significant rate of toxicity on healthy tissues. mTOR inhibitors showed some adverse events, such as hyperglycemia, hyperlipidemia, hypophosphatemia, hematologic toxicities, and mucocutaneous eruption, but the most important are still stomatitis and skin rash, often reported as dose-limiting side effects. PATIENTS AND METHODS: A search of the literature was performed by authors on the PubMed online database using the following key words: "sirolimus" OR "everolimus" OR "temsirolimus" OR "deforolimus" OR "ridaforolimus" combined with the Boolean operator AND with the terms: "stomatitis" OR "mucositis" OR "oral pain." Titles and abstracts of 382 potentially relevant studies were screened; of these, 114 studies were excluded because they did not report the inclusion criteria. In the second round, 268 studies were read full-text, but only 135 reported the inclusion criteria and were included for data extraction. Of the included studies, 95 referred to everolimus use, 16 to ridaforolimus, and 26 to temsirolimus (two studies referred to both everolimus and temsirolimus). RESULTS: The incidence rate of stomatitis according to the agent used was 25.07% (3,959/15,787) for everolimus, 27.02% (724/2,679) for temsirolimus, and 54.76% (598/1,092) for ridaforolimus. All the three agents analyzed showed high rates of low-grade stomatitis (G1-G2), while the onset of severe stomatitis (G3-G4) was rare. CONCLUSIONS: Analysis of the reports with patients treated with everolimus, temsirolimus, and ridaforolimus showed a clear prevalence of stomatitis grade 1 or 2. These data differ from that of patients treated with conventional chemotherapy in which mucositis is predominantly of grade 3 or 4.

Age-related changes of bone mineral density in mandible by quantitative computed tomography.

Quantitative Computed Tomography (QCT) was used to investigate age-related changes in trabecular bones of the mandible. The volumetric Bone Mineral Density (vBMD) of mandibles was found to be increasing with aging in the 20-29, 30-39, 40-49 age groups, while resulted decreasing in the 50~ years age group in a Chinese population. The aim of this study was to validate QCT as a reliable method to measure the vBMD of the mandible and to assess vBMD of the mandible in a Chinese population. A total of seven hundred and eighteen volunteers (299 males, 419 females), ranging from 20 to 63 years of age, previously enrolled in another study, were included for vBMD measurements by QCT. A total of 50 subjects were enrolled for the validation of QCT measurement. Basic information (age, height and weight), and vBMD of the mandible (middle, body and angle) were recorded. Comparisons among age and sex groups were analyzed using the Mann-Whitney test. Linear correlation analysis between vBMD and age was performed. The mandibular vBMD was twice measured with QCT by one operator and resulted highly repeatable (ICC 0. 97, P 0. 05). The vBMD in the middle of the mandible was the highest, followed by that in the body and at the angle of mandible. In each age group, the mean vBMD increased with aging except for the 50~ years age group (P less than 0.05) in which it decreased. The mean mandibular vBMD was higher in females than males in each age group (P less than 0.05). Correlation between vBMD and age was statistically significant (r=0.15, P less than 0.01). QCT shows high precision for the measurement of BMD in the mandible. The present study provides normative data of the mandible in an age- and sex-stratified manner, which can be helpful in clinical practice.

Ultrastructural, protein and photosynthetic alterations induced by Pb and Cd in Cynara cardunculus L., and its potential for phytoremediation.

The effects of cadmium and lead were investigated in Cynara cardunculus L. Plant uptake by root and shoot, changes in cell ultrastructure and photosynthetic efficiency, photosynthetic key protein levels, as well as regulation of stress-induced Hsp70 were examined. Cynara cardunculus accumulated Cd and Pb in their tissue, with a different trend for the two metals. The prompt translocation of Cd to the shoot may justify the ultrastructural injuries, especially observed in chloroplasts. However, Cd- treated plants did not show any decline in photochemistry; it is likely that Cd in shoot tissue triggers defense mechanisms, increasing the level of proteins involved in photosynthesis (i.e., Rubisco and D1 increased 7 and 4.5 fold respectively) as a compensatory response to neutralize chloroplast damage. The accumulation of Pb mainly in root, can explain the increase in Hsp70 level (23 folds) in this tissue. Pb reached the shoots, even at low amounts, causing an overall significant change in some photochemical parameters (QY and NPQ decreases and increases of 25%, respectively). The results suggest a higher sensitivity of C. cardunculus to Pb than Cd, although maximal photochemical efficiency suggests that this species seems to tolerate Pb and Cd and hence, it is a suitable candidate for phytoremediation.

Incidence and hospitalisation rates of Lyme borreliosis, France, 2004 to 2012.

Lyme borreliosis (LB) has become a major concern recently, as trends in several epidemiological studies indicate that there has been an increase in this disease in Europe and America over the last decade. This work provides estimates of LB incidence and hospitalisation rates in France. LB data was obtained from the Sentinelles general practitioner surveillance network (2009­2012) and from the Programme de Médicalisation des Systèmes d'Information (PMSI) data processing centre for hospital discharges (2004­09). The yearly LB incidence rate averaged 42 per 100,000 inhabitants (95% confidence interval (CI): 37­48), ranging from 0 to 184 per 100,000 depending on the region. The annual hospitalisation rate due to LB averaged 1.55 per 100,000 inhabitants (95% CI: 1.42­1.70). Both rates peaked during the summer and fall and had a bimodal age distribution (5­10 years and 50­70 years). Healthcare providers should continue to invest attention to prompt recognition and early therapy for LB, whereas public health strategies should keep promoting use of repellent, daily checks for ticks and their prompt removal.

Leaf anatomy and photochemical behaviour of Solanum lycopersicum L. plants from seeds irradiated with low-LET ionising radiation.

Plants can be exposed to ionising radiation not only in Space but also on Earth, due to specific technological applications or after nuclear disasters. The response of plants to ionising radiation depends on radiation quality/quantity and/or plant characteristics. In this paper, we analyse some growth traits, leaf anatomy, and ecophysiological features of plants of Solanum lycopersicum L. "Microtom" grown from seeds irradiated with increasing doses of X-rays (0.3, 10, 20, 50, and 100 Gy). Both juvenile and compound leaves from plants developed from irradiated and control seeds were analysed through light and epifluorescence microscopy. Digital image analysis allowed quantifying anatomical parameters to detect the occurrence of signs of structural damage. Fluorescence parameters and total photosynthetic pigment content were analysed to evaluate the functioning of the photosynthetic machinery. Radiation did not affect percentage and rate of seed germination. Plants from irradiated seeds accomplished the crop cycle and showed a more compact habitus. Dose-depended tendencies of variations occurred in phenolic content, while other leaf anatomical parameters did not show distinct trends after irradiation. The sporadic perturbations of leaf structure, observed during the vegetative phase, after high levels of radiation were not so severe as to induce any significant alterations in photosynthetic efficiency.

Plant growth promoting rhizobacteria (PGPR) application for coping with salinity and drought: a bibliometric network multi-analysis.

Rhizobacteria play a crucial role in plant growth and yield, stimulating primary production and improving stress resistance. Climate change has several consequences worldwide that affect arable land and agriculture. Studies on plant-soil-microorganism interactions to enhance plant productivity and/or resistance to abiotic stress may open new perspectives. This strategy aims to make agricultural-relevant plant species able to complete their biological cycle in extreme soils with the help of inoculated or primed plant growth-promoting rhizobacteria (PGPR). We provide an overview of the evolution of interest in PGPR research in the last 30 years through: (i) a quantitative search on the Scopus database; (ii) keyword frequencies and clustering analysis, and (iii) a keyword network and time-gradient analysis. The review of scientific literature on PGPR highlighted an increase in publications in the last 15 years, and a specific time gradient on subtopics, such as abiotic stresses. The rise in PGPR as a keyword co-occurring with salinity and drought stresses aligns with the growing number of papers from countries directly or partly affected by climate change. The study of PGPR, its features, and related applications will be a key challenge in the next decades, considering climate change effects on agriculture. The increased interest in PGPR leads to deeper knowledge focused specifically on researching agriculturally sustainable solutions for soils affected by salinity and drought.

Multitraits evaluation of a Solanum pennellii introgression tomato line challenged by combined abiotic stress.

Rising daily temperatures and water shortage are two of the major concerns in agriculture. In this work, we analysed the tolerance traits in a tomato line carrying a small region of the Solanum pennellii wild genome (IL12-4-SL) when grown under prolonged conditions of single and combined high temperature and water stress. When exposed to stress, IL12-4-SL showed higher heat tolerance than the cultivated line M82 at morphological, physiological, and biochemical levels. Moreover, under stress IL12-4-SL produced more flowers than M82, also characterized by higher pollen viability. In both lines, water stress negatively affected photosynthesis more than heat alone, whereas the combined stress did not further exacerbate the negative impacts of drought on this trait. Despite an observed decrease in carbon fixation, the quantum yield of PSII linear electron transport in IL12-4-SL was not affected by stress, thereby indicating that photochemical processes other than CO2 fixation acted to maintain the electron chain in oxidized state and prevent photodamage. The ability of IL12-4-SL to tolerate abiotic stress was also related to the intrinsic ability of this line to accumulate ascorbic acid. The data collected in this study clearly indicate improved tolerance to single and combined abiotic stress for IL12-4-SL, making this line a promising one for cultivation in a climate scenario characterized by frequent and long-lasting heatwaves and low rainfall.

The efficient physiological strategy of a novel tomato genotype to adapt to chronic combined water and heat stress.

Climate change is increasing the frequency of high temperature shocks and water shortages, pointing to the need to develop novel tolerant varieties and to understand the mechanisms employed to withstand combined abiotic stresses. Two tomato genotypes, a heat-tolerant Solanum lycopersicum accession (LA3120) and a novel genotype (E42), previously selected as a stable yielding genotype under high temperatures, were exposed to single and combined water and heat stress. Plant functional traits, pollen viability and physiological (leaf gas exchange and chlorophyll a fluorescence emission measurements) and biochemical (antioxidant content and antioxidant enzyme activity) measurements were carried out. A Reduced Representation Sequencing approach allowed exploration of the genetic variability of both genotypes to identify candidate genes that could regulate stress responses. Both abiotic stresses had a severe impact on plant growth parameters and on the reproductive phase of development. Growth parameters and leaf gas exchange measurements revealed that the two genotypes used different physiological strategies to overcome individual and combined stresses, with E42 having a more efficient capacity to utilize the limiting water resources. Activation of antioxidant defence mechanisms seemed to be critical for both genotypes to counteract combined abiotic stresses. Candidate genes were identified that could explain the different physiological responses to stress observed in E42 compared with LA3120. Results here obtained have shown how new tomato genetic resources can be a valuable source of traits for adaptation to combined abiotic stresses and should be used in breeding programmes to improve stress tolerance in commercial varieties.

Biology and crop production in Space environments: Challenges and opportunities.

Long-term manned space-exploration missions and the permanence of human colonies on orbital stations or planetary habitats will require the regeneration of resources onboard or in-situ. Bioregenerative Life Support Systems (BLSSs) are artificial environments where different compartments, involving both living organisms and physical-chemical processes, are integrated to achieve a safe, self-regulating, and chemically balanced Earth-like environment to support human life. Higher plants are key elements of such systems and Space greenhouses represent the producers' compartment. Growing plants in Space requires the knowledge of their growth responses not only to all environmental factors acting on Earth, but also to specific Space constraints such as altered gravity, ionizing radiations and confined volume. Moreover, cultivation techniques need to be adjusted considering such limitations. The type and intensity of environmental factors to be taken into account depend on the mission scenarios. Here, we summarize constraints and opportunities of cultivating higher plants in Space to regenerate resources and produce fresh food onboard. Both biological and agro-technological issues are considered briefly going through experiments both ground-based on Earth and in Space.

Impact of glucocorticoid-induced adverse events on adherence in patients receiving long-term systemic glucocorticoid therapy.

BACKGROUND: Factors influencing adherence to long-term (i.e. ≥ 3 months) systemic glucocorticoid therapy are poorly understood. OBJECTIVE: To evaluate the relationship between glucocorticoid-induced adverse events and therapeutic adherence in patients on long-term glucocorticoid treatment. METHODS: A cross-sectional survey was conducted in three departments of dermatology/internal medicine between April and September 2008. Patients were asked to provide data regarding symptoms they attributed to glucocorticoids, and adherence to treatment was measured using the four-item Morisky-Green adherence scale. Logistic regression analyses were used to assess the association between reported adverse events and adherence to glucocorticoids. RESULTS: A total of 255 questionnaires were completed and analysed [women 78%; median age 48 years (interquartile range (IQR) 34-65); connective tissue diseases 59%; median duration of treatment 24 months (IQR 8-72); median daily dose 10 mg (IQR 6-20)]. Among these 255 patients, 199 (78%) reported themselves as 'good adherents' and 56 (22%) as 'poor adherents' to treatment. Poor adherence was associated with younger age [odds ratio (OR) 0·97, 95% confidence interval (CI) 0·95-0·99, per increasing year; P < 0·01], presence of glucocorticoid-induced epigastralgia (OR 4·02, 95% CI 2·00-8·09; P < 0·01) and presence of glucocorticoid-induced morphological changes (OR 2·49, 95% CI 1·19-5·21; P = 0·02). Moreover, patients with poor adherence were likely to report concomitantly poor adherence to dietary advice associated with glucocorticoid therapy (OR 2·44, 95% CI 1·12-5·26; P = 0·02). CONCLUSIONS: As with other chronic therapies, the presence of glucocorticoid-induced adverse events is associated with an altered self-reported adherence to glucocorticoids. Patients who report epigastric pain or morphological changes that they associate with glucocorticoid therapy are particularly at risk of poor adherence. Adherence to dietary advice associated with glucocorticoid therapy may be an indirect measure of treatment adherence.

Micro and macro population effects in disease transmission: the case of varicella.

Profiles of varicella-zoster virus (VZV) seroprevalence have shown large variability in European countries in which vaccination has not been implemented. Differences in micro and macro population structures (e.g. household and municipality, respectively) may explain such variability, which is the focus of a population-based study of varicella in 12,000 children from 7800 French households in Corsica. The cumulative incidence was 89% at age 11 years, as the median age at infection was 5 years in first-born children, but decreased to 3.9 years in younger siblings. Hazard of infection in households increased as the first-born child initially enrolled in primary school. Age at infection was higher in less populated areas. Household attack rates increased with age (55% in <6 months, >90% in >3 years) and household secondary attack rate was approximately 70%. Several levels of population structure independently affect age at varicella infection.

Dust accumulation due to anthropogenic impact induces anatomical and photochemical changes in leaves of Centranthus ruber growing on the slope of the Vesuvius volcano.

In Mediterranean ecosystems, some natural areas are exposed to severe anthropogenic impact. Especially in summer, the considerable number of tourists visiting such areas, often with vehicles, causes deposition of dust over the vegetation due to formation of powder clouds, also favoured by wind erosion, high temperature, low precipitation and incoherent soil structure. The main aim of this study was to analyse whether the deposition of dust can induce changes in leaf anatomical functional traits and in the efficiency of photosynthetic apparatus in Centranthus ruber, a species widespread in Mediterranean ecosystems. Leaf morpho-functional traits were quantified in plants growing at sites characterised by high (HD) and low (LD) dust deposition, in periods with high anthropogenic impact. Analyses included quantification of chlorophyll fluorescence emission parameters, photosynthetic pigment concentration as well as stomatal size and frequency, leaf lamina thickness, quantification of intercellular spaces and phenolics in the mesophyll through microscopy. The overall analysis suggested that the different conditions of dust deposition induced different adjustment of morpho-functional traits in leaves of C. ruber. High dust deposition shielded the leaf lamina, protecting the photosynthetic apparatus from excess light and favoured plant photochemical efficiency. Leaves exposed to low dust deposition showed higher accumulation of phenolic compounds, protecting chloroplast membranes and characterised by high thermal dissipation of excess light. Such adaptive phenomena can affect vegetation dynamics due to possible different species-specific plant responses, resulting in different plant competitiveness under the limiting conditions of Mediterranean environments.

Suitability of Solanum lycopersicum L. 'Microtom' for growth in Bioregenerative Life Support Systems: exploring the effect of high-LET ionising radiation on photosynthesis, leaf structure and fruit traits.

The realisation of manned space exploration requires the development of Bioregenerative Life Support Systems (BLSS). In such self-sufficient closed habitats, higher plants have a fundamental role in air regeneration, water recovery, food production and waste recycling. In the space environment, ionising radiation represents one of the main constraints to plant growth. In this study, we explore whether low doses of heavy ions, namely Ca 25 Gy, delivered at the seed stage, may induce positive outcomes on growth and functional traits in plants of Solanum lycopersicum L. 'Microtom'. After irradiation of seed, plant growth was monitored during the whole plant life cycle, from germination to fruit ripening. Morphological parameters, photosynthetic efficiency, leaf anatomical functional traits and antioxidant production in leaves and fruits were analysed. Our data demonstrate that irradiation of seeds with 25 Gy Ca ions does not prevent achievement of the seed-to-seed cycle in 'Microtom', and induces a more compact plant size compared to the control. Plants germinated from irradiated seeds show better photochemical efficiency than controls, likely due to the higher amount of D1 protein and photosynthetic pigment content. Leaves of these plants also had smaller cells with a lower number of chloroplasts. The dose of 25 Gy Ca ions is also responsible for positive outcomes in fruits: although developing a lower number of berries, plants germinated from irradiated seeds produce larger berries, richer in carotenoids, ascorbic acid and anthocyanins than controls. These specific traits may be useful for 'Microtom' cultivation in BLSS in space, in so far as the crew members could benefit from fresh food richer in functional compounds that can be directly produced on board.

Electropermeabilization of nematode eggs for parasite deactivation.

The eggs of parasitic helminth worms are incredibly resilient - possessing the ability to survive changing environmental factors and exposure to chemical treatments - which has restricted the efficacy of wastewater sanitation. This research reports on the effectiveness of electroporation to permeabilize ova of Caenorhabditis elegans (C. elegans), a helminth surrogate, for parasite deactivation. This technique utilizes electric pulses to increase cell membrane permeability in its conventional application, but herein is used to open pores in nonparasitic nematode eggshells - the first report of such an application to the best knowledge of the authors. A parametric evaluation of electric field strength and total electroporation duration of eggs and worms in phosphate-buffered saline was performed using a 1 Hz pulse train of 0.01% duty cycle. The extent of pore formation was determined using a fluorescent label, propidium iodide, targeting C. elegans embryonic DNA. The results of this research demonstrate that electroporation increases eggshell permeability. This treatment, coupled with existing methods of electrochemical disinfection, could improve upon current attempts at the deactivation of helminth eggs. We discuss electroporation treatment conditions and likely modification of the lipid-rich permeability barrier within the eggshell strata.

Dual infections by influenza A/H3N2 and B viruses and by influenza A/H3N2 and A/H1N1 viruses during winter 2007, Corsica Island, France.

BACKGROUND: The investigation of dual influenza infection human cases is of major interest specifically for the control of new emerging influenza strains. OBJECTIVES: Using RT-PCR assays, we retrospectively assessed the prevalence of dual influenza virus infections that occurred in patients during the 2006-2007 winter season in Corsica Island (France). STUDY DESIGN: One hundred and thirty-four nasal swabbing samples taken from patients suffering from influenza-like illness between February and March 2007 were analysed using a rapid influenza antigen detection test, cell culture and RT-PCR assays. RESULTS AND CONCLUSION: Influenza viruses were detected in 93 (69.4%) of 134 patients with influenza-like illness using the combination of classical and molecular assays. Dual respiratory infections by influenza viruses were detected in 3 (3.2%) of the 93 influenza positive patients, including two cases of infection by influenza A/H3N2 and B viruses and one case of dual infection by influenza A/H3N2 and A/H1N1 viruses. In the present report, human co-infection cases by two influenza viruses appeared as a rare event in symptomatic patients. However, the virological and epidemiological mechanisms that determine the occurrence of dual influenza infections remain to be fully investigated in further prospective multicentric studies.

Paraheliotropism in Robinia pseudoacacia L.: an efficient strategy to optimise photosynthetic performance under natural environmental conditions.

We assessed the contribution of leaf movements to PSII photoprotection against high light and temperature in Robinia pseudoacacia. Gas exchange and chlorophyll a fluorescence measurements were performed during the day at 10:00, 12:00, 15:00 and 18:00 hours on leaves where paraheliotropic movements were restrained (restrained leaves, RL) and on control unrestrained leaves (UL). RL showed a strong decrease of net photosynthesis (A(n)), stomatal conductance (g(sH2O)), quantum yield of electron transport (PhiPSII), percentage of photosynthesis inhibited by O2 (IPO) and photochemical quenching (q(P)) in the course of the day, whereas, a significant increase in C(i)/C(a) and NPQ was observed. Contrary to RL, UL had higher photosynthetic performance that was maintained at elevated levels throughout the day. In the late afternoon, A(n), g(sH2O), PhiPSII and q(P) of RL showed a tendency to recovery, as compared to 15:00 hours, even if the values remained lower than those measured at 10:00 hours and in UL. In addition, contrary to UL, no recovery was found in F(v)/F(m) at the end of the study period in RL. Data presented suggest that in R. pseudoacacia, leaf movements, by reducing light interception, represent an efficient, fast and reversible strategy to overcome environmental stresses such as high light and temperature. Moreover, paraheliotropism was able to protect photosystems, avoiding photoinhibitory damage, leading to a carbon gain for the plant.

Performance of three cardoon cultivars in an industrial heavy metal-contaminated soil: Effects on morphology, cytology and photosynthesis.

In the present work the cytomorphological and physiological effects on three cardoon cultivars - Sardo, Siciliano, Spagnolo - grown in a metal-polluted soil, were investigated, to assess the traits concurring to the high tolerance to metal stress observed in cv. Spagnolo compared to the other two cultivars. The plants were grown for one month on a real polluted soil collected at a dismantling battery plant, highly enriched by heavy metals, especially Cd and Pb, and their leaves were analyzed by a multidisciplinary approach. TEM observations highlighted severe ultrastructural damage in Sardo and Siciliano, and preserved cytological traits in Spagnolo. Both pigment content and photochemistry indicated a decline in photosynthesis in Sardo and Sicilano and a substantial stability of the same parameters in Spagnolo. Protein analysis indicated a decrease in D1 level in all cultivars; in Spagnolo the D1 decrease was more pronounced and associated to a significant increase in Rubisco, a pattern likely preserving photosynthetic efficiency and high biomass production. In conclusion, Spagnolo cardoon was able to face metal stress through a prompt, multiple response balancing structural and functional traits.

Physiological, biochemical and molecular responses to water stress and rehydration in Mediterranean adapted tomato landraces.

Mediterranean tomato landraces adapted to arid environments represent an option to counteract drought, and to address the complexity of responses to water deficit and recovery, which is a crucial component of plant adaptation mechanisms. We investigated physiological, biochemical and molecular responses of two Mediterranean tomato landraces, 'Locale di Salina' (Lc) and 'Pizzutello di Sciacca' (Pz) under two dehydration periods and intermediate rehydration in greenhouse pot experiments. Relationship between CO2 assimilation (A) and stomatal conductance under severe water stress (gs  < 0.05 mol·m-2 ·s-1 ) indicated the occurrence of stomatal and non-stomatal limitations of photosynthesis. Gas exchange promptly recovered within 2-3 days of rehydration. ABA and gs showed a strict exponential relationship. Both leaf ABA and proline peaked under severe water stress. Lc showed higher accumulation of ABA and higher induction of the expression of both NCED and P5CS genes than Pz. Poly(ADP-ribose) polymerase increased during imposition of stress, mainly in Lc, and decreased under severe water stress. The two landraces hardly differed in their physiological performance. Under severe water stress, gs showed low sensitivity to ABA, which instead controlled stomatal closure under moderate water stress (gs  > 0.15 mol·m-2 ·s-1 ). The prompt recovery after rehydration of both landraces confirmed their drought-tolerant behaviour. Differences between the two landraces were instead observed at biochemical and molecular levels.

Injuries in the competitive paediatric motocross athlete.

PURPOSE: The purpose of this study is to report the spectrum of injuries sustained by competitive paediatric motocross athletes at a level I trauma centre. PATIENTS AND METHODS: A retrospective study of paediatric competitive motocross injuries treated at a level I trauma centre between 2004 and 2014 was performed. Athletes were included if aged less than 18 years and injured while practising or competing on a competitive motocross track. Medical records were reviewed for age, gender, race, location of accident, use of safety equipment, mechanism of injury, injury type and severity, Glasgow Coma Score at hospital presentation and Injury Severity Score (ISS). RESULTS: In total, 35 athletes were studied. The average age was 14 years. One athlete died. Thirty athletes were injured during competition; five were injured during practice. Twenty-four athletes (69%) suffered an orthopaedic injury with a total of 32 fractures and two dislocations. Two fractures were open (6.3%). Lower extremity fractures were twice as common as upper extremity fractures. Surgery was more common for lower extremity fractures-83% versus 30%. The most common fractures were femoral shaft (18.8%), fibula (12.5%), clavicle (12.5%), tibial shaft (9.4%) and forearm (9.4%). CONCLUSIONS: Competitive paediatric motocross athletes suffer serious, potentially life-threatening injuries despite the required use of protective safety equipment. Femoral shaft, fibula and clavicle were found to be the most commonly fractured bones. Further prospective research into track regulations, protective equipment and course design may reduce the trauma burden in this athlete population.