Adaptation of perennial flowering phenology across the European range of Arabis alpina

Flowering phenology is important in the adaptation of many plants to their local environment, but its adaptive value has not been extensively studied in herbaceous perennials. We used Arabis alpina as a model system to determine the importance of flowering phenology to fitness of a herbaceous perennial with a wide geographical range. Individual plants representative of local genetic diversity (accessions) were collected across Europe, including in Spain, the Alps and Scandinavia. The flowering behaviour of these accessions was documented in controlled conditions, in common-garden experiments at native sites and in situ in natural populations. Accessions from the Alps and Scandinavia varied in whether they required exposure to cold (vernalization) to induce flowering, and in the timing and duration of flowering. By contrast, all Spanish accessions obligately required vernalization and had a short duration of flowering. Using experimental gardens at native sites, we show that an obligate requirement for vernalization increases survival in Spain. Based on our analyses of genetic diversity and flowering behaviour across Europe, we propose that in the model herbaceous perennial A. alpina, an obligate requirement for vernalization, which is correlated with short duration of flowering, is favoured by selection in Spain where the plants experience a long growing season.

[Olfactory rehabilitation via retronasal olfaction using a tracheoesophageal voice prosthesis after total laryngectomy. German version]

BACKGROUND

Despite the variety of existing methods for olfactory rehabilitation after total laryngectomy, olfactory disability remains one of the main factors limiting quality of life for laryngectomees.

OBJECTIVE

Considering the need for a socially acceptable rehabilitation method that is suitable for everyday use, this study sought to elucidate whether retronasal olfaction during phonation through a tracheoesophageal voice prosthesis is possible.

MATERIALS AND METHODS

The odor identification of 22 laryngectomees was assessed using the Sniffin' Sticks test battery (12 odors), while performing an established method of olfactory rehabilitation-"polite yawning"-or while transnasal expiration or phonation through the tracheoesophageal fistula (TF). To facilitate the latter, a novel Expiratory Nasal Airflow M‑Maneuver (ENAMM) was developed.

RESULTS

All 21 non-anosmic laryngectomees included in the study were able to identify odors retronasally. While only 6 of 22 patients (27.3%) could perform the nasal expiration through the TF, all patients could easily perform phonation using ENAMM after proper instruction. The odor identification scores with the ENAMM technique did not statistically differ from ones with "polite yawning" (5.4 ± 3.1 vs. 6.4 ± 3.2, p = 0.279). The ENAMM was easy to learn and showed a tendency of increasing olfactory scores over time, possibly due to a learning effect.

CONCLUSIONS

Study results show that retronasal olfaction using a voice prosthesis after total laryngectomy is possible and suggest the potential of ENAMM as a method of olfactory rehabilitation for laryngectomy patients.

Young Individuals Are More Stable and Stand More Upright When Using Rollator Assistance During Standing up and Sitting Down

Four-wheeled walkers or rollators are often used to assist older individuals in maintaining an independent life by compensating for muscle weakness and reduced movement stability. However, limited biomechanical studies have been performed to understand how rollator support affects posture and stability, especially when standing up and sitting down. Therefore, this study examined how stability and posture change with varying levels of rollator support and on an unstable floor. The aim was to collect comprehensive baseline data during standing up and sitting down in young participants. In this study, 20 able-bodied, young participants stood up and sat down both 1) unassisted and assisted using a custom-made robot rollator simulator under 2) full support and 3) touch support. Unassisted and assisted performances were analyzed on normal and unstable floors using balance pads with a compliant surface under each foot. Using 3D motion capturing and two ground-embedded force plates, we compared assistive support and floor conditions for movement duration, the relative timing of seat-off, movement stability (center of pressure (COP) path length and sway area), and posture after standing up (lower body sagittal joint angles) using ANOVA analysis. The relative event of seat-off was earliest under full support compared to touch and unassisted conditions under normal but not under unstable floor conditions. The duration of standing up and sitting down did not differ between support conditions on normal or unstable floors. COP path length and sway area during both standing up and sitting down were lowest under full support regardless of both floor conditions. Hip and knee joints were least flexed under full support, with no differences between touch and unassisted in both floor conditions. Hence, full rollator support led to increased movement stability, while not slowing down the movement, during both standing up and sitting down. During standing up, the full support led to an earlier seat-off and a more upright standing posture when reaching a stable stance. These results indicate that rollator support when handles are correctly aligned does not lead to the detrimental movement alterations of increased forward-leaning. Future research aims to verify these findings in older persons with stability and muscle weakness deficiencies.

[Teaching during the COVID-19 pandemic: how do medical students evaluate interactive video-based distance bedside teaching in otorhinolaryngology?]

Hintergrund

Der Beginn der ersten SARS-CoV-2-Pandemie-Welle im März 2020 erforderte erhebliche Umstellungsmaßnahmen in der medizinischen Lehre mit vollständigem Verzicht auf direkten Kontakt von Studierenden und Patienten. Vor diesem Hintergrund wurde das Lehrformat „Unterricht am Patienten“ (UaP) als interaktiver, videobasierter Distanzunterricht am Patienten etabliert und durchgeführt.

Fragestellung

Ziel der Studie war die Erfassung der studentischen Beurteilung dieses Lehrkonzeptes im Fach Hals-Nasen-Ohren-Heilkunde.

Material und Methoden

Die Live-Übertragung erfolgte aus einem HNO-Untersuchungsraum zu den im Hörsaal befindlichen Studierenden, welche mit den Patienten interagieren konnten. Makro-, mikro- und endoskopische Untersuchungsbefunde wurden in Echtzeit in den Hörsaal übertragen. Die Evaluation erfolgte anhand eines Online-Fragebogens, welcher 13 geschlossene Fragen (Likert-Skala) beinhaltete, sowie als offenes Feedback in freier Textform.

Ergebnisse

Die Rücklaufquote lag bei 16,8 % (42 von 250 Studierenden). Davon hatten 85,7 % einen positiven Gesamteindruck, und Tenor war, dass das Konzept angesichts der Umstände gut umgesetzt wurde. Dennoch könne auf einen direkten Patientenkontakt eher nicht verzichtet werden, auch wenn eine teilweise Kompensation durch Videoschaltung möglich sei. Insgesamt wurde das Lehrkonzept als lehrreich empfunden, und die Studierenden konnten sich vorstellen, zukünftig häufiger auch ein solches UaP-Lehrkonzept zu nutzen.

Schlussfolgerung

Dieses Lehrkonzept kann den direkten Patientenkontakt nicht ersetzen, stellt jedoch speziell im HNO-Gebiet eine gute Alternative dar, wenn durch pandemiebedingte Umstände ein „klassischer“ UaP nicht möglich ist. Aspekte des interaktiven, videobasierten Distanzunterrichts am Patienten könnten auch zukünftig in andere Lehrformate integriert werden.

[The first year of the SARS-CoV-2 pandemic-impact on otorhinolaryngology]

BACKGROUND

The first year of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has already affected our public health care system to an enormous extent and will continue to do so in the future. Otorhinolaryngologists (ORLs) are suspected to be at high risk of infection, due to the high viral load in the mucosa of the upper airways. The current review evaluates the impact of the pandemic on ORLs' activities and assesses the risk infection.

METHODS

A selective literature research was conducted using relevant English and German terms for ORL, SARS-CoV‑2, risk, and infection at PubMed, medRxiv, and bioRxiv, as well as in the Deutsches Ärzteblatt and on the websites of the Robert Koch Institute and the Johns Hopkins University.

RESULTS

Protection recommendations for ORL include general hygiene measures and wearing KN95 masks for routine professional activities. When in contact with coronavirus disease 2019 (COVID-19) patients, it is recommended to extend the personal protective equipment by eye protection, gloves, cap, and gown. International otorhinolaryngology societies have released guidelines for procedures (e.g., tracheostomy, sinus surgery), propagating personal protection for the surgical team and reduction of aerosols. Testing for SARS-CoV‑2 in patients and medical staff can contribute to reducing the risk of infection. Vaccination would provide some additional protection for ORLs and other health care professionals with increased exposure to aerosols. There is increasing evidence that ORLs are at a high risk of contracting SARS-CoV‑2.

CONCLUSION

Consequent personal protection, frequent testing of patients and health care professionals, and the promised SARS-CoV‑2 vaccinations may provide adequate protection for highly exposed persons.

A new concept for temporal gating of synchrotron X-ray pulses

A new concept for temporal gating of synchrotron X-ray pulses based on laser-induced thermal transient gratings is presented. First experimental tests of the concept yield a diffraction efficiency of 0.18%; however, the calculations indicate a theoretical efficiency and contrast of >30% and 10-5, respectively. The full efficiency of the pulse picker has not been reached yet due to a long-range thermal deformation of the sample after absorption of the excitation laser. This method can be implemented in a broad spectral range (100 eV to 20 keV) and is only minimally invasive to an existing setup.

[Functional results after soft palate reconstruction in oropharyngeal cancer patients]

BACKGROUND

Surgery of the soft palate in patients with oropharyngeal cancer can result in functional deficiencies of swallowing and speech. Reconstruction of the resected structures can contribute to regaining sufficient functionality after therapy.

OBJECTIVE

The current study used frequency analysis to evaluate the change in speech characteristics after resection and reconstruction of the soft palate during post-therapeutic follow-up.

MATERIALS AND METHODS

In 18 patients with oropharyngeal carcinoma and involvement of the soft palate, resection and reconstruction by free radial forearm graft (FRFG) and adjuvant chemoradiotherapy was conducted. The spoken German numbers "eins", "zwei", "drei", "vier", "fünf" were recorded during follow-up and objectively assessed by frequency analysis. Additionally, food intake status and the necessity of a tracheostomy were evaluated.

RESULTS

The maximum peak frequencies of the numbers analysed increased from 150-300 Hz before up to 1000 Hz after therapy. Two years post therapy, the peak frequencies again declined to levels comparable to those before tumour therapy. One year after therapy, complete oral nutrition was possible in two thirds of patients and the tracheostomy was closed in 80%.

CONCLUSION

Reconstruction of the soft palate by FRFG during the course of oropharyngeal cancer treatment allows function to be regained with respect to speech and swallowing. In the majority of patients, it is possible to reach a level of function comparable to the state before tumour treatment.

Reciprocal space slicing: A time-efficient approach to femtosecond x-ray diffraction

An experimental technique that allows faster assessment of out-of-plane strain dynamics of thin film heterostructures via x-ray diffraction is presented. In contrast to conventional high-speed reciprocal space-mapping setups, our approach reduces the measurement time drastically due to a fixed measurement geometry with a position-sensitive detector. This means that neither the incident (ω) nor the exit ( 2 θ ) diffraction angle is scanned during the strain assessment via x-ray diffraction. Shifts of diffraction peaks on the fixed x-ray area detector originate from an out-of-plane strain within the sample. Quantitative strain assessment requires the determination of a factor relating the observed shift to the change in the reciprocal lattice vector. The factor depends only on the widths of the peak along certain directions in reciprocal space, the diffraction angle of the studied reflection, and the resolution of the instrumental setup. We provide a full theoretical explanation and exemplify the concept with picosecond strain dynamics of a thin layer of NbO₂.

Diagnosis and treatment of isolated snoring-open questions and areas for future research

STUDY OBJECTIVES

Snoring is a common phenomenon which is generated by vibration of soft tissue of the upper airway during sleep. Due to the high incidence of isolated snoring and the substantial burden for the patient and the bed partner, a thorough examination and appropriate therapy are required. Many recommendations for the treatment of isolated snoring are either not evidence-based or are derived from recommendations for the management of obstructive sleep apnea. Therefore, the aim of this study is the identification and description of open questions in the diagnosis and treatment of isolated snoring and the illustration of areas for further research.

METHODS

In the context of the development of the new version of the German guideline "Diagnosis and treatment of isolated snoring in adults," a multidisciplinary team of experts performed a systematic literature search on the relevant medical data and rated the current evidence regarding the key diagnostic and therapeutic measures for snoring.

RESULTS

The systematic literature review identified 2293 articles. As a major inclusion criterion, only studies on primary snoring based on objective sleep medical assessment were selected. After screening and evaluation, 33 full-text articles remained for further analysis. Based on these articles, open questions and areas for future research were identified for this review.

CONCLUSION

Several major gaps in the literature on the diagnosis and treatment of isolated snoring were identified. For the majority of diagnostic and therapeutic measures for snoring, high-level scientific evidence is still lacking.

Measurement of relative lung perfusion with electrical impedance and positron emission tomography: an experimental comparative study in pigs

BACKGROUND

Electrical impedance tomography (EIT) with indicator dilution may be clinically useful to measure relative lung perfusion, but there is limited information on the performance of this technique.

METHODS

Thirteen pigs (50-66 kg) were anaesthetised and mechanically ventilated. Sequential changes in ventilation were made: (i) right-lung ventilation with left-lung collapse, (ii) two-lung ventilation with optimised PEEP, (iii) two-lung ventilation with zero PEEP after saline lung lavage, (iv) two-lung ventilation with maximum PEEP (20/25 cm H₂O to achieve peak airway pressure 45 cm H₂O), and (v) two-lung ventilation under unilateral pulmonary artery occlusion. Relative lung perfusion was assessed with EIT and central venous injection of saline 3%, 5%, and 10% (10 ml) during breath holds. Relative perfusion was determined by positron emission tomography (PET) using ⁶⁸Gallium-labelled microspheres. EIT and PET were compared in eight regions of equal ventro-dorsal height (right, left, ventral, mid-ventral, mid-dorsal, and dorsal), and directional changes in regional perfusion were determined.

RESULTS

Differences between methods were relatively small (95% of values differed by less than 8.7%, 8.9%, and 9.5% for saline 10%, 5%, and 3%, respectively). Compared with PET, EIT underestimated relative perfusion in dependent, and overestimated it in non-dependent, regions. EIT and PET detected the same direction of change in relative lung perfusion in 68.9-95.9% of measurements.

CONCLUSIONS

The agreement between EIT and PET for measuring and tracking changes of relative lung perfusion was satisfactory for clinical purposes. Indicator-based EIT may prove useful for measuring pulmonary perfusion at bedside.

Tracking picosecond strain pulses in heterostructures that exhibit giant magnetostriction

We combine ultrafast X-ray diffraction (UXRD) and time-resolved Magneto-Optical Kerr Effect (MOKE) measurements to monitor the strain pulses in laser-excited TbFe₂/Nb heterostructures. Spatial separation of the Nb detection layer from the laser excitation region allows for a background-free characterization of the laser-generated strain pulses. We clearly observe symmetric bipolar strain pulses if the excited TbFe₂ surface terminates the sample and a decomposition of the strain wavepacket into an asymmetric bipolar and a unipolar pulse, if a SiO₂ glass capping layer covers the excited TbFe₂ layer. The inverse magnetostriction of the temporally separated unipolar strain pulses in this sample leads to a MOKE signal that linearly depends on the strain pulse amplitude measured through UXRD. Linear chain model simulations accurately predict the timing and shape of UXRD and MOKE signals that are caused by the strain reflections from multiple interfaces in the heterostructure.

Progressive ratio (PR) schedules and the sipometer: Do they measure wanting, liking, and/or reward? A tribute to Anthony Sclafani and Karen Ackroff

This paper honors the contributions made by Anthony (Tony) Sclafani and Karen Ackroff to both the Columbia University Seminar on Appetitive Behavior and to the field of ingestive behavior in general. We review their use of the progressive ratio (PR) licking paradigm, to determine whether the taste of sucrose, independent of its post-ingestive effects, is always positively reinforcing in animals. They demonstrated a monotonic increase in licking as concentration increased, and obtained results identical to those obtained with a lever-pressing paradigm, but licking was easier and more natural than lever pressing. The PR paradigm was translated to evaluate liquid food reward value in humans. An instrument (the sipometer) was devised that initially permitted a few seconds access to small amounts of a sweet beverage as the participants increased the time to obtain it in 3-5-sec increments. The device went through two refinements and currently delivers the reinforcer and measures the pressure exerted to obtain it. The sipometer is compared with other techniques for measuring motivation and reward. The use of the sipometer and the PR method are discussed in relation to the theoretical challenges inherent in measuring motivation and pleasure, from both psychological and behavioral economics perspectives, and why it is or is not important to separate these processes for both theoretical and practical applications.

Spatiotemporal Coherent Control of Thermal Excitations in Solids

X-ray reflectivity measurements of femtosecond laser-induced transient gratings (TG) are applied to demonstrate the spatiotemporal coherent control of thermally induced surface deformations on ultrafast time scales. Using grazing incidence x-ray diffraction we unambiguously measure the amplitude of transient surface deformations with sub-Å resolution. Understanding the dynamics of femtosecond TG excitations in terms of superposition of acoustic and thermal gratings makes it possible to develop new ways of coherent control in x-ray diffraction experiments. Being the dominant source of TG signal, the long-living thermal grating with spatial period Λ can be canceled by a second, time-delayed TG excitation shifted by Λ/2. The ultimate speed limits of such an ultrafast x-ray shutter are inferred from the detailed analysis of thermal and acoustic dynamics in TG experiments.

Altered epigenetic features in circulating nucleosomes in idiopathic pulmonary fibrosis

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal lung disorder of unknown origin with a highly variable and unpredictable clinical course. Polymorphisms and environmentally induced epigenetic variations seem to determine individual susceptibility to the development of lung fibrosis.

METHODS

We have studied circulating epitopes on cell-free nucleosomes (cfnucleosomes) in 50 IPF patients. We have compared untreated IPF (n = 23) with IPF receiving antifibrotic therapy (n = 27) and healthy subjects (HS) (n = 27). We analyzed serum levels of five cfnucleosomes including bound HMGB1 (nucleosomes adducted to high-mobility growth protein B1), mH2A1.1 (nucleosomes containing the histone variant mH2A1.1), 5mC (nucleosomes associated with methylated DNA), and H3K9Ac and H3K27Ac (nucleosomes associated with histone H3 acetylated at lysine 9 or 27 residue).

RESULTS

Our findings showed that serum levels of bound HMGB1, mH2A1.1, 5mC, H3K9Ac, and H3K27Ac were significantly lower in IPF patients than in HS (p < 0.001, p < 0.001, p < 0.01, p < 0.001, and p < 0.0001, respectively). Moreover, we found differences in epigenetic profiles between untreated IPF patients and those receiving anti-fibrotic therapy with mH2A1.1 and 5mC being significantly lower in untreated than in treated patients (p < 0.01 and p < 0.05, respectively). Combination of four cfnucleosomes (HMGB1, 5mC, H3K9Ac, and H3K27Ac) allow to discriminate IPF vs HS with a good coefficient of determination (R² = 0.681). The AUC for the ROC curve computed by this logistic regression was 0.93 (p < 0.001) with 91% sensitivity at 80% specificity.

CONCLUSION

Our observations showed that cfnucleosomes (bound HMGB1, mH2A1.1, 5mC, H3K9Ac, and H3K27Ac) might have potential as biomarkers for diagnosis and treatment response. These results deserve further validation in longitudinal cohorts.

[The Interdisciplinary Conference on Lacrimal System Disorders of ophthalmic and ENT surgeons at the University Hospital Halle : An analysis of present patient material]

BACKGROUND AND AIM

The lacrimal system (LS) crosses regions of ocular adnexa, the nose, and the paranasal sinuses. Surgery of disorders requires a targeted ophthalmologic and otolaryngologic examination. Since 2013, an Interdisciplinary Conference on Lacrimal System Disorders (ICLSD) has existed at the University Hospital Halle. First results of our experiences with this cooperation between ophthalmic and ENT surgeons are presented.

METHODS

In a retrospective study at the Department of Ophthalmology, University Hospital Halle, all patients aged 22-80 years (n = 43, 10 with bilateral manifestation; mean age 65.1 years) having had a consultation in ICLSD between February 2013 and May 2015 were analyzed. Thereby, 53 LS were included in the descriptive evaluation.

RESULTS

The main relevant pathology in terms of ophthalmologic manifestation was chronic dacryocystitis and its complications (n = 42), whereas nasal septum deviation (n = 11) and chronic rhinosinusitis (n = 10) were the most frequent otorhinolaryngologic pathologies. Prior to consultation, ENT (n = 34) and/or ophthalmic surgery (n = 40) had been performed. During ICLSD, an individualized therapeutic regime for each patient was developed. Surgery was required in 43 out of 53 LS. Of these, 32 were mainly ophthalmic, 11 mainly ENT interventions. At the time of evaluation (median 3 months; range 1 to 24 months), 29 out of 38 patients (76.3 %) were free of complaints.

CONCLUSION

Since 2013, competences of ophthalmic and ENT surgeons have been integrated in ICLSD for advanced diagnosis and therapy of lacrimal disorders at the University Hospital Halle. Encouraging functional results are shown in this study, as most patients have had a long and complicated history of lacrimal system disorders. ICLSD enables interdisciplinary patient care.

Development of Attachment and Exploratory Behavior in Infant Squirrel Monkeys under Controlled Rearing Conditions

This study contributes to the understanding of early development of communication in squirrel monkeys (Saimiri). Emission of expressive behavior as well as its perception (as concluded from the partner's responses) form the basis of social communication. We studied stimulus conditions that control attachment and exploratory behavior two interdependent fields of motivation which are especially important in the early stages of development.

Newborn squirrel monkeys were isolated from their mothers and the group and were provided with a mother surrogate, manipulanda, and social surrogate stimuli: objects were so designed as to elicit behavior which would otherwise be directed at conspecifics.

It was found that the animals displayed largely normal attachment and exploratory behavior. They modified their behavior depending on whether their contacts with the social surrogate were answered by aversive or non-aversive calls in the same sense as socially experienced conspecifics would do. Consequently, the conclusion may be drawn that specific genetic components are involved in comprehending emotional expressions.

Elasticity in portion selection is predicted by severity of anorexia and food type in adolescents

The size of portions that people select is an indicator of underlying mechanisms controlling food intake. Fears of eating excessive portions drive down the sizes of portions patients with anorexia nervosa (AN) can tolerate eating significantly below those of healthy controls (HC) (Kissileff et al., 2016). To determine whether patients with AN will also reduce the sizes of typical or ideal portions below those of controls, ANOVA was used to compare maximum tolerable, typical, and ideal portions of four foods (potatoes, rice, pizza, and M&M's) in the same group of 24 adolescent AN patients and 10 healthy adolescent controls (HC), on which only the maximal portion data were previously reported. Typical and ideal portion sizes did not differ on any food for AN, but for HC, typical portions sizes (kcals) became larger than ideal as the energy density of the food increased, and were significant for the most energy dense food. Ideal portions of low energy dense foods were the same for AN as for in HC. There was a significant 3-way (group × food × portion type) interaction, such that HC selected larger maximum than typical portions only for pizza. We therefore proposed that individuals of certain groups, depending on the food, can be flexible in the amounts of food chosen to be eaten. We call this difference between maximum-tolerable, and typical portion sizes selected "elasticity." Elasticity was significantly smaller for AN patients compared to HC for pizza and was significantly inversely correlated with severity of illness. This index could be useful for clinical assessment of AN patients, and those with eating problems such as in obesity and bulimia nervosa and tracking their response to treatment.

[Upper airway stimulation in obstructive sleep apnea]

The stimulation of the upper airway represents an effective treatment option in case of CPAP failure in patients with moderate to severe obstructive sleep apnea. The stimulation with respiratory sensing (Inspire Medical Systems) has shown a high level of evidence in larger cohorts and longer follow-up studies. Whether the results of the stimulation without respiratory sensing (ImThera Medical) can be compared with the therapy with sensing, remains open up to now. Additional data are awaited after the planned phase III study THN#2. To optimize both procedure and to provide long term results, more studies are needed. The workgroup "sleep medicine" of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery supports theses activities with the help of the newly founded task force "Neurostimulation in Sleep Apnea".

Large-scale adaptive differentiation in the alpine perennial herb Arabis alpina

Information about the incidence and magnitude of local adaptation can help to predict the response of natural populations to a changing environment, and should be of particular interest in arctic and alpine environments where the effects of climate change are expected to be severe. To quantify adaptive differentiation in the arctic-alpine perennial herb Arabis alpina, we conducted reciprocal transplant experiments for 3 yr between Spanish and Scandinavian populations. At the sites of one Spanish and one Scandinavian population, we planted seedlings representing two Spanish and four Scandinavian populations, and recorded survival, flowering propensity and fecundity. The experiment was replicated in two subsequent years. The results demonstrate strong adaptive differentiation between A. alpina populations from the two regions. At the field site in Spain, survival and fruit production of Spanish populations were higher than those of Scandinavian populations, while the opposite was true at the site in Scandinavia, and these differences were consistent across years. By comparison, fitness varied little among populations from the same region. The results suggest that the magnitude and geographical scale of local adaptation need to be considered in predictions of the effects of global change on the dynamics of arctic and alpine plant populations.

Brillouin scattering of visible and hard X-ray photons from optically synthesized phonon wavepackets

We monitor how destructive interference of undesired phonon frequency components shapes a quasi-monochromatic hypersound wavepacket spectrum during its local real-time preparation by a nanometric transducer and follow the subsequent decay by nonlinear coupling. We prove each frequency component of an optical supercontinuum probe to be sensitive to one particular phonon wavevector in bulk material and cross-check this by ultrafast x-ray diffraction experiments with direct access to the lattice dynamics. Establishing reliable experimental techniques with direct access to the transient spectrum of the excitation is crucial for the interpretation in strongly nonlinear regimes, such as soliton formation.

Following strain-induced mosaicity changes of ferroelectric thin films by ultrafast reciprocal space mapping

We investigate coherent phonon propagation in a thin film of ferroelectric PbZr(0.2)Ti(0.8)O(3) (PZT) by ultrafast x-ray diffraction experiments, which are analyzed as time-resolved reciprocal space mapping in order to observe the in- and out-of-plane structural dynamics, simultaneously. The mosaic structure of the PZT leads to a coupling of the excited out-of-plane expansion to in-plane lattice dynamics on a picosecond time scale, which is not observed for out-of-plane compression.

Normalization schemes for ultrafast x-ray diffraction using a table-top laser-driven plasma source

We present an experimental setup of a laser-driven x-ray plasma source for femtosecond x-ray diffraction. Different normalization schemes accounting for x-ray source intensity fluctuations are discussed in detail. We apply these schemes to measure the temporal evolution of Bragg peak intensities of perovskite superlattices after ultrafast laser excitation.

GeBP/GPL transcription factors regulate a subset of CPR5-dependent processes

The CONSTITUTIVE EXPRESSOR OF PATHOGENESIS-RELATED GENES5 (CPR5) gene of Arabidopsis (Arabidopsis thaliana) encodes a putative membrane protein of unknown biochemical function and displays highly pleiotropic functions, particularly in pathogen responses, cell proliferation, cell expansion, and cell death. Here, we demonstrate a link between CPR5 and the GLABRA1 ENHANCER BINDING PROTEIN (GeBP) family of transcription factors. We investigated the primary role of the GeBP/GeBP-like (GPL) genes using transcriptomic analysis of the quadruple gebp gpl1,2,3 mutant and one overexpressing line that displays several cpr5-like phenotypes including dwarfism, spontaneous necrotic lesions, and increased pathogen resistance. We found that GeBP/GPLs regulate a set of genes that represents a subset of the CPR5 pathway. This subset includes genes involved in response to stress as well as cell wall metabolism. Analysis of the quintuple gebp gpl1,2,3 cpr5 mutant indicates that GeBP/GPLs are involved in the control of cell expansion in a CPR5-dependent manner but not in the control of cell proliferation. In addition, to our knowledge, we provide the first evidence that the CPR5 protein is localized in the nucleus of plant cells and that a truncated version of the protein with no transmembrane domain can trigger cpr5-like processes when fused to the VP16 constitutive transcriptional activation domain. Our results provide clues on how CPR5 and GeBP/GPLs play opposite roles in the control of cell expansion and suggest that the CPR5 protein is involved in transcription.

Trichome specific expression of the tobacco (Nicotiana sylvestris) cembratrien-ol synthase genes is controlled by both activating and repressing cis-regions

Tobacco (Nicotiana sylvestris) glandular trichomes make an attractive target for isoprenoid metabolic engineering because they produce large amounts of one type of diterpenoids, alpha- and beta-cembratrien-diols. This article describes the establishment of tools for metabolic engineering of tobacco trichomes, namely a transgenic line with strongly reduced levels of diterpenoids in the exudate and the characterization of a trichome specific promoter. The diterpene-free tobacco line was generated by silencing the major tobacco diterpene synthases, which were found to be encoded by a family of four highly similar genes (NsCBTS-2a, NsCBTS-2b, NsCBTS-3 and NsCBTS-4), one of which is a pseudogene. The promoter regions of all four CBTS genes were sequenced and found to share over 95% identity between them. Transgenic plants expressing uidA under the control of the NsCBTS-2a promoter displayed a specific pattern of GUS expression restricted exclusively to the glandular cells of the tall secretory trichomes. A series of sequential and internal deletions of the NsCBTS-2a promoter led to the identification of two cis-acting regions. The first, located between positions -589 to -479 from the transcription initiation site, conferred a broad transcriptional activation, not only in the glandular cells, but also in cells of the trichome stalk, as well as in the leaf epidermis and the root. The second region, located between positions -279 to -119, had broad repressor activity except in trichome glandular cells and is mainly responsible for the specific expression pattern of the NsCBTS-2a gene. These results establish the basis for the identification of trans-regulators required for the expression of the CBTS genes restricted to the secretory cells of the glandular trichomes.

Dinoflagellate 17S rRNA sequence inferred from the gene sequence: Evolutionary implications

We present the complete sequence of the nuclear-encoded small-ribosomal-subunit RNA inferred from the cloned gene sequence of the dinoflagellate Prorocentrum micans. The dinoflagellate 17S rRNA sequence of 1798 nucleotides is contained in a family of 200 tandemly repeated genes per haploid genome. A tentative model of the secondary structure of P. micans 17S rRNA is presented. This sequence is compared with the small-ribosomal-subunit rRNA of Xenopus laevis (Animalia), Saccharomyces cerevisiae (Fungi), Zea mays (Planta), Dictyostelium discoideum (Protoctista), and Halobacterium volcanii (Monera). Although the secondary structure of the dinoflagellate 17S rRNA presents most of the eukaryotic characteristics, it contains sufficient archaeobacterial-like structural features to reinforce the view that dinoflagellates branch off very early from the eukaryotic lineage.