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Copyright of Anaesthesiologie & Intensivmedizin is the property of DGAI e.V. - Deutsche Gesellschaft fur Anasthesiologie und Intensivmedizin e.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Premixed flames exhibit different asymptotic regimes of interaction between heat release and turbulence depending on their respective length scales. At high Karlovitz number, the dilatation caused by heat release does not have any relevant effect on turbulent kinetic energy with respect to non-reacting flow, while at low Karlovitz number, the mean shear is a sink of turbulent kinetic energy, and counter-gradient transport is observed. This latter phenomenon is not well captured by closure models commonly used in Large Eddy Simulations that are based on gradient diffusion. The massive amount of data available from Direct Numerical Simulation (DNS) opens the possibility to develop data-driven models able to represent physical mechanisms and non-linear features present in both these regimes. In this work, the databases are formed by DNSs of two planar hydrogen/air flames at different Karlovitz numbers corresponding to the two asymptotic regimes. In this context, the Generative Adversarial Network (GAN) gives the possibility to successfully recognize and reconstruct both gradient and counter-gradient phenomena if trained with databases where both regimes are included. Two GAN models were first trained each for a specific Karlovitz number and tested using the same dataset in order to verify the capability of the models to learn the features of a single asymptotic regime and assess its accuracy. In both cases, the GAN models were able to reconstruct the Reynolds stress subfilter scales accurately. Later, the GAN was trained with a mixture of both datasets to create a model containing physical knowledge of both combustion regimes. This model was able to reconstruct the subfilter scales for both cases capturing the interaction between heat release and turbulence closely to the DNS as shown from the turbulent kinetic budget and barycentric maps. [ABSTRACT FROM AUTHOR]

Current industry standard environmental verification testing methods typically employ a single shaker to subject a component to a desired environment in one axis at a time, which has been shown to result in over- or under-testing on the various axes and hence a poor representation of the desired environment. This paper explores a new verification testing methodology based on a combination of the Transmission Simulator Substructuring Method (TSM) with the Impedance Matched Multi Axis Testing (IMMAT) method. The new method seeks to verify the survival of a subcomponent in a given environment using only environmental measurements on the structure to which the subcomponent is attached. A Transmission Simulator (TS) is used to maintain the same connection geometry between the subcomponent and the rest of the vehicle such that the dynamics of the subcomponent are better matched. Impedance Matched Multi Axis Testing is then used to recreate the full environment on the Transmission Simulator in all axes at once. If the impedance between the Transmission Simulator and the subcomponent is sufficiently similar and if the control is successful in reproducing the response on the Transmission Simulator, the motion of the subcomponent of interest should match its motion in the desired environment and produce an accurate reconstruction test. To evaluate this new methodology, simulations were performed using roving hammer data both to optimize the test design and to evaluate the best possible performance. Multi-input-multi-output (MIMO) tests were then performed using a commercial control system to assess the accuracy of the method. These cases showed that the proposed approach was able to reconstruct the desired environment with moderate accuracy, but the response away from the Transmission Simulator was found to be very sensitive to the design of the Transmission Simulator. [ABSTRACT FROM AUTHOR]

Background: Williams syndrome (WS) and autism spectrum disorder (ASD) are neurodevelopmental disorders that demonstrate overlapping genetic associations, dichotomous sociobehavioral phenotypes, and dichotomous pathological differences in neuronal distribution in key social brain areas, including the prefrontal cortex and the amygdala. The serotonergic system is critical to many processes underlying neurodevelopment and is additionally an important neuromodulator associated with behavioral variation. The amygdala is heavily innervated by serotonergic projections, suggesting that the serotonergic system is a significant mediator of neuronal activity. Disruptions to the serotonergic system, and atypical structure and function of the amygdala, are implicated in both WS and ASD. Methods: We quantified the serotonergic axon density in the four major subdivisions of the amygdala in the postmortem brains of individuals diagnosed with ASD and WS and neurotypical (NT) brains. Results: We found opposing directions of change in serotonergic innervation in the two disorders, with ASD displaying an increase in serotonergic axons compared to NT and WS displaying a decrease. Significant differences (p < 0.05) were observed between WS and ASD data sets across multiple amygdala nuclei. Limitations: This study is limited by the availability of human postmortem tissue. Small sample size is an unavoidable limitation of most postmortem human brain research and particularly postmortem research in rare disorders. Conclusions: Differential alterations to serotonergic innervation of the amygdala may contribute to differences in sociobehavioral phenotype in WS and ASD. These findings will inform future work identifying targets for future therapeutics in these and other disorders characterized by atypical social behavior. [ABSTRACT FROM AUTHOR]

This work presents the first simultaneous X‐ray measurement and high‐speed video observation of the propagation of a lightning leader producing X‐rays. As a result, the three‐dimensional leader distance from the X‐ray measurement and, for the first time, the conditions of the preexisting channel during the leader propagation were observed. Although four leaders in this seven‐stroke flash followed the same path to ground, X‐rays were only observed during the leader before the return stroke with the highest peak current. The fact that the other three leaders following the same path to ground did not produce detectable X‐rays confirms the hypothesis that leader line charge density is an important factor that determines X‐ray production. The fact that X‐rays was recorded only when the leader tip was at a certain portion of the lightning channel confirms that the orientation of the leader plays an important role in the detection of X‐rays. Plain Language Summary: It was known that lightning can produce X‐rays. However, in this study, thanks to the use of a high‐speed video camera it was possible to determine when lightning produces X‐rays, how far it was, how it was oriented when the detection of X‐rays, and what the conditions of the preexisting channel were during the leader propagation. The observations of the present work allow for new insights, confirmation of some hypotheses, and comparison with past studies. The results presented help to understand why X‐rays are sometimes detected and sometimes not. It is shown that the amount of charge transferred by the discharge plays a crucial role. This study also confirms that the orientation of the descending leader plays an important role in the detection of X‐rays. Key Points: First high‐speed video observation of a natural lightning leader producing X‐rays during its propagation to groundExperimental confirmation that the production of X‐rays depends on the leader charge density in natural lightningThe orientation of the leader plays an important role in the detection of X‐rays [ABSTRACT FROM AUTHOR]

Most of the terpenes in wines are conjugated to various sugars, representing a significant reservoir of aromatic precursors. To promote the release of these terpenes, certain enzymes, such as β-glucosidase, α-arabinosidase and α-rhamnosidase, are necessary. A simple and cost-effective procedure for the immobilisation of multiple glycosidase activities (β-D-glucopyranosidase, α-L-arabinofuranosidase, α-L-rhamnopyranosidase and β-D-xylopyranosidase) from commercial Aspergillus niger preparation onto magnetic beads as carriers was developed as reported in Part 1 (Ferner et al. 2016). The aim of this work was to analyse a possible application of this immobilised biocatalyst due to its wellknown advantages over soluble enzyme preparations – that is, control of the reaction process and preparation of enzyme-free products. Volatile compounds were analysed by gas chromatography (mass spectrometric detection). After the treatment of the model wine with different glycosides and white wine with immobilised glycosidases, the amount of free terpenes was significantly increased with respect to that of the control wine. The results of this study are of considerable interest for possible future applications of immobilised enzymes in the wine-making industry. [ABSTRACT FROM AUTHOR]

Copyright of Der Onkologe is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The amygdala is a medial temporal lobe structure implicated in social and emotional regulation. In typical development (TD), the amygdala continues to increase volumetrically throughout childhood and into adulthood, while other brain structures are stable or decreasing in volume. In autism spectrum disorder (ASD), the amygdala undergoes rapid early growth, making it volumetrically larger in children with ASD compared to TD children. Here we explore: (a) if dendritic arborization in the amygdala follows the pattern of protracted growth in TD and early overgrowth in ASD and (b), if spine density in the amygdala in ASD cases differs from TD from youth to adulthood. The amygdala from 32 postmortem human brains (7-46 years of age) were stained using a Golgi-Kopsch impregnation. Ten principal neurons per case were selected in the lateral nucleus and traced using Neurolucida software in their entirety. We found that both ASD and TD individuals show a similar pattern of increasing dendritic length with age well into adulthood. However, spine density is (a) greater in young ASD cases compared to age-matched TD controls (<18 years old) and (b) decreases in the amygdala as people with ASD age into adulthood, a phenomenon not found in TD. Therefore, by adulthood, there is no observable difference in spine density in the amygdala between ASD and TD age-matched adults (≥18 years old). Our findings highlight the unique growth trajectory of the amygdala and suggest that spine density may contribute to aberrant development and function of the amygdala in children with ASD. [ABSTRACT FROM AUTHOR]

Purpose : To evaluate feasibility of automatic software-based path proposals for CT-guided percutaneous biopsies. Methods : Thirty-three patients (60 $$\pm $$ 12 years) referred for CT-guided biopsy of focal liver lesions were consecutively included. Pre-interventional CT and dedicated software (FraunhoferMeVis Pathfinder) were used for (semi)automatic segmentation of relevant structures. The software subsequently generated three path proposals in downward quality for CT-guided biopsy. Proposed needle paths were compared with consensus proposal of two experts (comparable, less suitable, not feasible). In case of comparable results, equivalent approach to software-based path proposal was used. Quality of segmentation process was evaluated (Likert scale, 1 $$=$$ best, 6 $$=$$ worst), and time for processing was registered. Results : All biopsies were performed successfully without complications. In 91 % one of the three automatic path proposals was rated comparable to experts' proposal. None of the first proposals was rated not feasible, and 76 % were rated comparable to the experts' proposal. 7 % automatic path proposals were rated not feasible, all being second choice ( $$n=1$$ ) or third choice ( $$n=6$$ ). In 79 %, segmentation at least was good. Average total time for establishing automatic path proposal was 42 $$\pm $$ 9 s. Conclusion : Automatic software-based path proposal for CT-guided liver biopsies in the majority provides path proposals that are easy to establish and comparable to experts' insertion trajectories. [ABSTRACT FROM AUTHOR]

This noninterventional, prospective study investigated the administration of tapentadol prolonged release (PR; the dosage form described in this article is commercially available in Germany as Palexia retard; Grünenthal GmbH, Aachen) for severe chronic pain in routine clinical practice over a 3-month period. Effectiveness analyses included data from 3134 patients; 1331 received World Health Organization (WHO) Step III pretreatment. A total of 97.8% of patients received long-term analgesic pretreatment (42.5% with strong opioids). Switching to tapentadol PR produced a 3.9-point mean pain reduction (baseline, 7.0 ± 1.5; end of observation, 3.1 ± 1.8; 11-point numerical rating scale; descriptive P value ≤.001); 72.1% of patients experienced clinically relevant pain relief (≥50%) at the end of observation. Significant decreases in pain-related impairment of daily activities and improvements in quality of life (descriptive P value ≤.001) were observed with tapentadol PR with good tolerability. Tapentadol PR was effective for various pain indications in patients previously receiving strong opioids (67.2% achieved clinically relevant pain relief). Tapentadol PR can be considered an alternative therapy to classical opioids for treatment of severe chronic pain. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate pharmacogenetic determinants of skin rash associated with epidermal growth factor receptor (EGFR) inhibitor treatment. A total of 109 prospectively sampled cancer patients, receiving the first treatment with an EGFR inhibitor, were genotyped for functional EGFR polymorphisms and tagging variants in genes involved in receptor downstream signaling. Skin rash was absent in 26 (23.9%) patients and associated with shorter overall survival compared with patients presenting skin rash (P=0.005). The EGFR polymorphisms, 497G/A (P=0.008), and the haplotypes of the promoter variants, EGFR-216G/T and -191C/A (P=0.029), were associated with the appearance of skin rash. In addition, a common haplotype in the PIK3CA gene was associated with skin rash (P=0.045) and overall survival (P=0.009). In conclusion, genetic variation within the EGFR gene and its downstream signaling partner PIK3CA might predict EGFR-inhibitor-related skin rash. [ABSTRACT FROM AUTHOR]

The majority of patients with myelodysplastic syndrome (MDS) present with anemia and will become dependent on regular transfusions of packed red blood cells (PRBC) with the risk of iron overload (IOL). Liver iron content best reflects the total body iron content, and measurement of liver iron concentration (LIC) by MRI is a validated tool for detection, but data in MDS is rather limited. Here we present the results of a multi-center trial evaluating the efficacy and safety of deferasirox (DFX) in low and intermediate-1 risk MDS patients with transfusion-dependent IOL. Three patients with transfusion frequency of > 4 units PRBC per month were initially treated with 30 mg/kg/day while in 46 patients with a lower transfusion burden deferasirox was initiated at 20 mg/kg/day, due to patient related reasons one patient received DFX in a dose of 6 mg/kg/day only. LIC was measured by MRI at baseline and end of study using the method by St. Pierre et al. The intention to treat population consisted of 50 MDS patients (28 male; 22 female) with a median age of 69 years who were treated with DFX for a median duration of 354 days. Mean daily dose of DFX was 19 mg/kg/day. Median serum ferritin level (SF) at baseline was 2,447 ng/mL and decreased to 1,685 ng/mL (reduction by 31 %) at end of study ( p = 0.01). In 7 (13 %) patients the initially chosen dose had to be increased due to unsatisfactory efficacy of chelation therapy. For 21 patients, LIC measurement by liver MRI was performed at baseline and for 19 of these patients at the end of study: mean LIC decreased significantly from 16,8 mg/g dry tissue weight (± 8.3 mg/g dry tissue weight) at study entry to 10,8 mg/g dry tissue weight (± 10.4 mg/g dry tissue weight) at end of study ( p = 0.01). Of all patients exposed to the study drug ( n = 54), 28 (52 %) did not complete the 12 month study period most commonly due to AEs in 28 % ( n = 15) and abnormal laboratory values in 7 % ( n = 4), respectively. The most common adverse events (≥ 10 % of all patients) with suspected drug relationship were diarrhea ( n = 25, 46 %), nausea ( n = 13, 24 %), upper abdominal pain ( n = 8, 15 %), serum creatinine increase ( n = 16, 30 %) and rash ( n = 5, 9 %). Adverse events making dose adjustments or interruption of study drug necessary occurred in 33 patients (61 %). Hematologic improvement according to IWG criteria (2006) was observed in 6 patients (11 %). Initiation of treatment of IOL with DFX depending on the transfusion burden yields sufficient reduction of excess iron indicated by serum ferritin levels and most importantly by liver MRI. The safety profile of DFX was comparable to previous observations. [ABSTRACT FROM AUTHOR]

Background: Pompe disease (Glycogen storage disorder type II) is an inherited disease because of a lack or reduced activity of the enzyme α-1,4-glucosidase (acid maltase). Since 2006, an intravenous enzyme replacement therapy (ERT) with Myozyme™ (Genzyme Corporation, Cambridge, MA, USA) is available. Methods: Four adult patients aged between 39 and 68 years received ERT over a period of 6 months. Clinical and functional parameters were registered longitudinally. Results: In three patients, a considerable improvement of symptoms could be noticed, patients with pre-existing respiratory insufficiency seemed to profit most. In all patients, a continuous decrease of initially raised laboratory parameters (creatine kinase, lactic dehydrogenase, transaminases) was striking. Conclusions: Enzyme replacement therapy seems to be a long-term effective therapy in adult patients with Pompe disease. Whether all patients will profit from an improvement of symptoms or at least a stabilisation of the otherwise progressive disease is currently not definitively clear. [ABSTRACT FROM AUTHOR]

The role of the primate retrosplenial cortex (RSC) in memory processing and spatial navigation has been well established. Recently, processing emotionally salient information has been attributed to the RSC as well. Little anatomical data, however, exist linking the RSC with known emotional processing centers within the brain. The amygdala has been implicated as a substrate for modulating memory for emotionally salient events; yet no study to date has demonstrated that this area has a direct connection in the primate brain. With modern retrograde tracer injections into the RSC and adjacent cortical areas of the monkey ( Macaca fascicularis), we demonstrate that there are efferent projections from the basal nucleus of the amygdala to the RSC and area 31. These projections offer anatomical data supporting the hypothesis that the RSC might receive emotionally salient input directly from the amygdala and suggest a role for the RSC as a node within a neural system potentially capable of integrating emotional information for use in memory or other cognitive processes. [ABSTRACT FROM AUTHOR]

Introduction. This is a four-year follow-up of 25 men who received parenteral testosterone undecanoate (TU), 1000 mg every 12 weeks for at least four years. This study was a continuation of a 30-week study wherein the effects of TU had been compared to those of parenteral testosterone enanthate. Methods & Results. Plasma testosterone (T) trough values of the injection interval of 12 weeks): median 11.9 - 15.9 nmol/L (N 10.0-30.0). E2 and SHBG were stable. Body weight, BMI, waist-to-hip ratio remained stable. Total cholesterol, and triglycerides were unchanged but plasma LDL declined while HDL, after an initial reduction over the first 30 weeks, had increased significantly after three years. Leptin levels, bone mineral density, blood pressure, liver function tests, haemoglobin and haematocrit levels remained stable without values above the upper limit of normal. Over the first 12 months of the study there was an increase in prostate volume from 19.7 ± 8.8 mL to 22.0 ± 8.4 mL (p < 0.05) but thereafter volumes remained stable, paralleled by an increase in PSA from 0.67 ± 0.38 µg/dL to 0.75 ± 0.35 µg/dL (p < 0.05) without any further changes after 12 months. Conclusion. TU appears to be a stable and safe treatment modality of hypogonadal men. [ABSTRACT FROM AUTHOR]

Background. Integrated positron emission tomography (PET)/computed tomography (CT) scanners have been recently introduced in the diagnostic work-up of suspected pulmonary malignancy and demonstrate encouraging results in the staging of nonsmall-cell lung cancer. Objective. To evaluate the usefulness of integrated FDG PET/CT in pulmonary carcinoid tumours. Setting. University hospital. Methods. We studied 13 patients (mean age ± 1 SD, 57 ± 11 years) with pulmonary carcinoid tumours. All patients demonstrated a single pulmonary lesion. Integrated PET/CT scan and surgical resection were performed in all patients. Results. The pulmonary lesion size ranged from 1.1 to 5.0 cm. Final histological diagnosis confirmed 12 typical and one atypical pulmonary carcinoid. Mean proliferation rate of the typical carcinoids was 1.7 ± 1.4%. None of the patients had recurrent carcinoid disease or died during follow-up (864 ± 218 days). Mean standardized uptake value (SUV) of 18F-fluorodeoxyglucose (FDG) in typical carcinoids was 3.0 ± 1.5 (range 1.2 – 6.6); SUV in the atypical carcinoid was remarkably high with a value of 8.5. The SUV was lower than 2.5 in 6 of 12 patients (50%). Mediastinal lymph node metastases or extrathoracic metastases were not detected in any patient. Conclusions. 18F-fluorodeoxyglucose PET/CT imaging improves accurate localization of metabolic activity and thus the interpretation of pulmonary lesions on CT. FDG uptake in pulmonary carcinoid tumours is often lower than expected for malignant tumours. Therefore, surgical resection or biopsy of lesions suspected to be carcinoids should be mandatory, even if they show no hypermetabolism on FDG PET images. [ABSTRACT FROM AUTHOR]

) has proposed that the amygdala is an important component of the neural network that underlies social behavior. ) identified neuropathology in the amygdala of the postmortem autistic brain. These findings, along with recent functional neuroimaging data, have led ) to propose that dysfunction of the amygdala may be responsible, in part, for the impairment of social behavior that is a hallmark feature of autism. Recent data from studies in our laboratory on the effects of amygdala lesions in the adult and infant macaque monkey do not support a fundamental role for the amygdala in social behavior. If the amygdala is not essential for the component processes of social behavior, as seems to be case in both non-human primates and selected patients with bilateral amygdala damage, then it is unlikely to be the primary substrate for the impaired social behavior of autism. However, damage to the amygdala does have an effect on a monkey's response to normally fear-inducing stimuli, such as snakes, and removes a natural reluctance to engage novel conspecifics in social interactions. These findings lead to the conclusion that an important role for the amygdala is in the detection of threats and mobilizing an appropriate behavioral response, part of which is fear. Interestingly, an important comorbid feature of autism is anxiety ( ). If the amygdala is pathological in subjects with autism, it may contribute to their abnormal fears and increased anxiety rather than their abnormal social behavior. [ABSTRACT FROM AUTHOR]

Abstract: A series of conformationally constrained cyclic analogues of the peptide hormone bradykinin (BK, Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg) was synthesized to check different turned structures proposed for the bioactive conformation of BK agonists and antagonists. Cycles differing in the size and direction of the lactam bridge were performed at the C- and N-terminal sequences of the molecule. Glutamic acid and lysine were introduced into the native BK sequence at different positions for cyclization through their side chains. Backbone cyclic analogues were synthesized by incorporation of N-carboxy alkylated and N-amino alkylated amino acids into the peptide chain. Although the coupling of Fmoc-glycine to the N-alkylated phenylalanine derivatives was effected with DIC/HOAt in SPPS, the dipeptide building units with more bulky amino acids were pre-built in solution. For backbone cyclization at the C-terminus an alternative building unit with an acylated reduced peptide bond was preformed in solution. Both types of building units were handled in the SPPS in the same manner as amino acids. The agonistic and antagonistic activities of the cyclic BK analogues were determined in rat uterus (RUT) and guinea-pig ileum (GPI) assays. Additionally, the potentiation of the BK-induced effects was examined. Among the series of cyclic BK agonists only compound 3 with backbone cyclization between positions 2 and 5 shows a significant agonistic activity on RUT. To study the influence of intramolecular ring closure we used an antagonistic analogue with weak activity, [d-Phe[sup 7]]-BK. Side chain as well as backbone cyclization in the N-terminus of [d-Phe[sup 7]]-BK resulted in analogues with moderate antagonistic activity on RUT. Also, compound 18 in which a lactam bridge between positions 6 and 9 was achieved via an acylated reduced peptide bond has moderate antagonistic activity on RUT. These results support the hypothesis of turn structures in both parts of the molecule as a requirement for BK antagonism. Certain active and inactive agonists and antagonists are able to potentiate the bradykinin-induced contraction of guinea-pig ileum. [ABSTRACT FROM AUTHOR]

Abstract: Different types of dipeptide building units containing N‐ or C‐terminal arginine were prepared for synthesis of the backbone cyclic analogues of the peptide hormone bradykinin (BK: Arg‐Pro‐Pro‐Gly‐Phe‐Ser‐Pro‐Phe‐Arg). For cyclization in the N‐terminal sequence N‐carboxyalkyl and N‐aminoalkyl functionalized dipeptide building units were synthesized. In order to avoid lactam formation during the condensation of the N‐terminal arginine to the N‐alkylated amino acids at position 2, the guanidino function has to be deprotected. The best results were obtained by coupling Z‐Arg(Z)[sub 2]‐OH with TFFH/collidine in DCM. Another dipeptide building unit with an acylated reduced peptide bond containing C‐terminal arginine was prepared to synthesize BK‐analogues with backbone cyclization in theC‐terminus. To achieve complete condensation to the resin and to avoid side reactions during activation of the arginine residue, this dipeptide unit was formed on a hydroxycrotonic acid linker. HYCRAM[sup ™] technology was applied using the Boc‐Arg(Alloc)[sub 2]‐OH derivative and the Fmoc group to protect the aminoalkyl function. The reduced peptide bond was prepared by reductive alkylation of the arginine derivative with the Boc‐protected amino aldehyde, derived from Boc‐Phe‐OH. The best results for condensation of the branching chain to the reduced peptide bond were obtained using mixed anhydrides. Both types of dipeptide building units can be used in solid‐phase synthesis in the same manner as amino acid derivatives. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Orofacial Orthopedics/Fortschritte der Kieferorthopadie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Effects of water supply on gas exchange, carbon isotopic composition, and relative growth rate were compared among seedlings from three populations of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) grown in a controlled environment chamber. The three populations were chosen to represent high, moderate and low drought tolerance. There was no indication that drought tolerance was related to high water-use efficiency. Populations differed (P < 0.05) in relative growth rate (RGR), but did not differ (P > 0.10) in gas exchange variables or carbon isotope ratio (δ13C). Well-watered seedlings had significantly higher RGR, xylem pressure potential (Ψxpp), net photosynthesis (A), stomatal conductance to water vapor (g), and lower δ13C and instantaneous water-use efficiency than water-stressed seedlings. With decreasing Ψxpp, A decreased linearly, whereas g decreased exponentially. Seedlings of the highly drought-tolerant population were more sensitive to water availability than seedlings from the other populations; they used water quickly when water was available, but closed their stomata in response to water stress. We conclude that, in ponderosa pine, the drought avoidance mechanism is more important for survival and growth in arid and semiarid environments than the efficient use of water. [ABSTRACT FROM PUBLISHER]

Plastids are plant cellular organelles that are generally inherited from the maternal parent in the angiosperms. Many species exhibit biparental inheritance of plastids, but usually with a predominantly maternal influence. In contrast to this, we report strong paternal inheritance of plastids in reciprocal crosses of alfalfa, Medicago sativa, by following restriction fragment length polymorphisms for plastid DNA in two normal green plastids. Mitochondrial inheritance remained exclusively maternal. [ABSTRACT FROM AUTHOR]