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OBJECTIVE Medial thalamotomies were introduced in the late 1940s. Pain relief was shown to be achieved for all body locations. With some exceptions, these early relatively small series showed frequent, more or less complete recurrence of the original pain. The posterior part of the central lateral nucleus in the human medial thalamus was identified in the 1990s using multiarchitectonic studies and intraoperative single-cell recordings and was confirmed as a surgical target. This retrospective patient series extended over 11 years. Its goal was to demonstrate the efficacy and risk profile of the MR-guided focused ultrasound (MRgFUS) central lateral thalamotomy (CLT) against chronic and therapy-resistant neuropathic (i.e., neurogenic) pain. METHODS In this single-center, nonrandomized retrospective cross-sectional analysis of consecutive patients, 63 consecutive MRgFUS CLT interventions were performed in 55 patients. RESULTS The mean follow-up duration was 55 months. A total of 112 CLT targets were performed, and the CLT was applied bilaterally in 48 patients and contralateral to their pain in 7 patients. Repeat MRgFUS interventions were performed in 8 patients. One serious adverse event with numbness of the upper lip was recorded. The mean pain relief rated by patients was 42% ± 32% at 3 months, 43% ± 36% at 1 year, and 42% ± 37% at the last follow-up (n = 63). The proportions of cases with ≥ 30% pain relief were 65% at 3 months, 63% at 1 year, and 61% at the last follow-up. Good outcomes (≥ 50% pain relief) were found in 54% of patients at 3 months, 49% at 1 year, and 51% at the last follow-up. The reduction in mean VAS scores showed similar percentage reductions as those for pain relief (−41% for continuous pain and −49% for pain attacks) at the 1-year follow-up. The mean frequency of pain attacks was reduced by 92%. Allodynia was reduced or suppressed in 68% of patients and never appeared de novo after MRgFUS CLT. CONCLUSIONS These results suggest that MRgFUS CLT against neuropathic pain is a safe approach and its results are stable over time. At a mean follow-up duration of 55 months, the mean pain relief was 42% and more than 50% of patients still reported ≥ 50% pain relief. Patients with classical and idiopathic trigeminal neuralgia reported a higher mean pain relief compared with the whole patient group.

BACKGROUND The authors reported the case of a 66-year-old male patient with a 14-year history of right-sided severe episodic and therapy-resistant cluster headache (CH) who underwent bilateral central lateral thalamotomy (CLT) using incisionless transcranial magnetic resonance imaging–guided focused ultrasound (MRgFUS). OBSERVATIONS The patient experienced a single cluster headache attack 5 weeks after the procedure. There were no more pain attacks over the next 6 years of follow-up. LESSONS This treatment success may indicate a common pathophysiology for CH and neurogenic (neuropathic) pain, which has been treated with CLT for more than 30 years. Further experience is needed to assess the reproducibility of this case.

Jeanmonod, D. & Y. Naciri (2021). A taxonomic revision of Ranunculus sect. Batrachium in Corsica: a morphological and statistical analysis. Candollea 76: 275–292. In French, English and French abstracts. In Corsica, the species of Ranunculus sect. Batrachium DC. are poorly defined due to a lack of sufficient observations and because the group is taxonomically complex. Our study concerns 113 individuals collected around the whole island, and is based on a biometric study of 16 morphological characters and field observations (plant development, intrapopulation variability, ecology). As a result, several species are excluded from the section and the groups Ranunculus peltatus aggr., Ranunculus penicillatus aggr., and Ranunculus trichophyllus Chaix are retained. These groups are statistically discriminated by fruiting pedicel length and multifidous leaf length. The species present on the island are Ranunculus penicillatus (Dumort.) Bab., Ranunculus saniculifolius Viv. (initially attributed to Ranunculus peltatus aggr.), and Ranunculus trichophyllus Chaix. An identification key to Corsican species is provided, as well as information concerning the ecology and distribution of each species. First published online: October 13, 2021.

The Silene gigantea complex is characterized by a high degree of morphological variability that resulted in the description of three subspecies across its distribution range from the Balkan Peninsula to South-west Asia and Cyprus. In this work, we used nuclear and plastid markers in Bayesian phylogeographic analyses to investigate the taxonomy and the evolutionary history of S. gigantea. The results from plastid DNA partly support the existing taxonomic assessments since S. gigantea subsp. rhodopea is monophyletic, whereas S. gigantea subspp. gigantea and hellenica are clearly polyphyletic. This pattern suggests that a strong morphological convergence is associated with chasmophytic conditions. The results also suggest that the populations from the Epirus region (north-western Greece) did not arise from hybridization as previously claimed, but correspond to a new evolutionary lineage that is consequently described and named S. gigantea subsp. epirota. An identification key to the four subspecies is also given. Our phylogeographic study further highlights a genetic continuity across populations from the central and eastern Greek mainland to Chios and Turkey, all of them sharing the same plastid DNA haplotype and belonging to the same nuclear cluster. In addition, at least two separate colonization events are suggested for Crete. The Bayesian phylogeographic reconstruction clearly points to a post-Messinian diversification across the Aegean area. Considering the low seed dispersal ability of S. gigantea, a continuum of ancestral populations between islands and the mainland is assumed to have occurred during the last glaciations and to have played a key role in colonization processes.

We investigated the morphology of the Silene gigantea complex across its distribution range in the Balkan Peninsula, south-western Turkey and Cyprus. We performed a factorial analysis for mixed quantitative and qualitative variables followed by k-means analyses to determine the most probable morphological clustering within the species. A linear discriminant analysis was then computed using the DISQUAL method to test the a priori classification. The results indicate that three entities, which are consistent with the previously published taxonomic treatment, can be recognised. Moreover, our results show that the distribution of S. gigantea subsp. hellenica can be extended to Turkey, and that S. gigantea subsp. rhodopea is actually absent from this country, in contradiction to previous assessments. The global distribution of the S. gigantea complex is established and the morphological characteristics of each subspecies are discussed.

OBJECTIVESince the first clinical application of the incisionless magnetic resonance–guided focused ultrasound (MRgFUS) technology only small series of patients have been reported, and thus only extrapolations of the procedure-related risks could be offered. In this study, the authors analyze side-effects and targeting accuracy in 180 consecutive treatments with MRgFUS for chronic therapy-resistant idiopathic Parkinson’s disease (PD), essential tremor (ET), cerebellar tremor (CT), and neuropathic pain (NP), all performed in their dedicated center.METHODSA total of 180 treatments with MRgFUS for chronic therapy-resistant idiopathic PD, ET, CT, and NP were prospectively assessed for side-effects and targeting accuracy. Monitoring for later side-effects was continued for at least 3 months after the procedure in all but 1 case (0.6%); in that single case, the patient was lost to follow-up after an uneventful early postoperative course. The surgical targets were the pallidothalamic tract (pallidothalamic tractotomy, n = 105), the cerebellothalamic tract (cerebellothalamic tractotomy, n = 50), the central lateral nucleus (central lateral thalamotomy, n = 84), the centrum medianum (centrum medianum thalamotomy, n = 12), and the globus pallidus (pallidotomy, n = 2). Cognitive testing was performed before, 1–2 days after, and 1 year after the procedure. The Mini–Mental State Examination (MMSE) was used for the first 29 cases and was then replaced by the Montreal Cognitive Assessment (MoCA). Lesion reconstruction and measurement of targeting accuracy were done on 2-day posttreatment MR images for each performed target. To determine targeting accuracy measurement, 234 out of the 253 lesions depicted in the 2-day postoperative MR examination could be 3D-reconstructed.RESULTSThe mean MoCA score was slightly improved 2 days postoperatively (p = 0.002) and remained stable at 1-year follow-up (p = 0.03). The mean MMSE score was also slightly improved 2 days postoperatively and at 1-year follow-up, but the improvement was not statistically significant (p = 0.06 and p = 0.2, respectively). The mean (± SD) accuracy was 0.32 ± 0.29 mm, 0.29 ± 0.28 mm, and 0.44 ± 0.39 mm for the mediolateral, anteroposterior, and dorsoventral dimensions, respectively. The mean 3D accuracy was 0.73 ± 0.39 mm. As to side-effects, 14 events over 180 treatments were documented. They were classified into procedure-related (n = 4, 2.2%), effect on neighboring structures (n = 3, 1.7%), and disease-related (n = 7, 3.9%). There was no bleeding.CONCLUSIONSThe incisionless transcranial MRgFUS technology demonstrates a higher targeting accuracy and a lower side-effect profile than techniques requiring cerebral penetration. In the absence of penetration brain shift, this technique avoids the placement of a thermolesion away from the chosen target, thus suppressing the need for reversible therapeutic energy application. With the use of proper physiopathology-based targets, definitive therapeutic effects can be coupled with sparing of sensory, motor, and paralimbic/multimodal thalamocortical functions. Clinical efficacy, not analyzed in this investigation, will ultimately rest in proper target selection and optimized thermolesional coverage of the target.

Recent divergence can obscure species boundaries among closely related taxa.

Jeanmonod, D. (2020). Importance and characteristics of the Cyrno-continental taxa, and analysis of their absence outside Corsica. Candollea 75: 291–310. In French, English and French abstracts.Corsica contains a flora present on the European continent but absent from all the other large Mediterranean islands (Balearic Islands, Cyprus, Crete, Sardinia and Sicily). The study analyzes all the taxa of this flora called here Cyrno-continental and represented by 258 taxa (12 % of the native flora). Its characteristics (biological, biogeographical and chorological types, vegetation belts and habitats) are analyzed here and appear to be very different from those of the total native flora. This flora directly depends on the geographical characteristics of Corsica distinct from those of the other islands (latitude, reliefs, temperate vegetation belts in altitude) because 59.8 % of these taxa find their limits of distribution in Corsica. Some of them have found a postglacial refuge in Corsica, others have been able to establish themselves thanks to the great wealth of its habitats, notably humid. Others have limited distribution areas that have not allowed them to colonize other islands. Expansion capabilities, environmental change and chance also play a role in some cases.

Jeanmonod, D. (2018). Typification of the corsican names of taxa of the Burnat Herbarium (G-BU). Candollea 73: 61–74. In French, English and French abstracts. DOI: http//dx.doi.org/10.1553/c2018v731a6The Burnat herbarium (G-BU) is essential for the study of the Corsican flora but remains poorly known. A search for all the new names for Corsica and the associated original material used by various authors for their descriptions and present in this closed herbarium was carried out by various methods. Ninety eight names of taxa from Corsica were highlighted and 197 herbarium collections considered as original material were located. They correspond to the description of 9 species, 88 infraspecific taxa and 1 hybrid belonging to a broad taxonomic spectrum (26 families and 56 genera). Thirteen authors made these descriptions, mainly John Briquet (66 taxa), Eduard Hackel (7), Casimir Arvet-Touvet (6) and Rene Verriet de Litardiere (5). Among the type specimens, 48 are holotypes, 44 are lectotypes of which 39 are designated in the article, 7 are isotypes and the remaining represents syntypes. The exhaustive list of these names of taxa, their respective typification as well as their currently accepted names are provided.

Jeanmonod, D. (2017). Importance of Corsican specimens in the Geneva herbaria. Candollea 72 : 133–142. In French, English and French abstracts. http://dx.doi.org/10.15553/c2017v721a9 The Geneva herbaria contain about 100,000 specimens collected in Corsica, resulting in the interest of the Geneva botanists, e.g. John Briquet (1870–1931) for this insular mountain. 40 % of the collections are represented in the institutional database, with 331 collectors, the most frequent being notably R. Deschâtres, J. Gamisans, and R. de Litardiere. According to the database, the collection dates range from 1803 to 2015 with four major peaks during the 20th century. Ca. 250 types specimens are represented in Geneva. The geographical areas of the island are covered in a fairly homogeneous way, whereas the altitudinal belts from 0 to 100 m have the maximum coverage. All families and 95.7 % of specific and infraspecific taxa of native flora are present in the Geneva Corsican collections. Only 197 taxa of the wild fl...

Background: Trigeminal neuralgia (TN) is a recognized pain condition the treatment of which can be very challenging. Various surgical interventions can be applied in cases of therapy-resistance to drug treatments. The central lateral thalamotomy (CLT) against neurogenic (or neuropathic) pain is based on multiarchitectonic histological as well as physiopathological studies, and integrates the nucleus in a large thalamocortical (TC) and corticocortical network responsible for the sensory, cognitive and affective/emotional components of pain. The advent of the magnetic resonance imaging guided high intensity focused ultrasound (MRgFUS) brought a strong reduction in morbidity and increase in accuracy compared to penetration techniques. Objective: This study was aimed at analyzing the outcome of bilateral MRgFUS CLT for chronic therapy-resistant trigeminal pain, all performed in one single center. Methods: Patients were categorized in Classical, Idiopathic and Secondary TN. By definition, paroxysms lasted for seconds up to 2 min. All patients were screened for trigeminal neurovascular conflict. In case of classical TN, microvascular decompression was proposed. Therapy-resistance and thus indication for MRgFUS CLT was based on the lack of efficacy and/or side effects of antiepileptic and antidepressant drugs. Good outcome was defined by a pain relief ≥50%. Results: Eight patients suffering from chronic therapy-resistant trigeminal neuralgia were treated. All suffered from pain with paroxysmal character. Six patients reported additionally continuous pain. Mean follow-up was 53 months (range: 12-92, median: 60 months). The mean pain relief assessed by patients was 51% (median: 58%, range: 0-90%) at 3 months, 71% (median: 65%, range: 40-100%) at 1 year and 78% (median: 75%, range: 50-100%) at their longest follow-up. This represents 63% good outcomes at 3 months, 88% at 1 year and 100% at last follow-up. Frequency of the mean pain paroxysms decreased from 84 per day preoperative to 3.9 at 1 year postoperatively. There were no serious adverse events in this series. Conclusion: Our study provides preliminary support for the safety and efficacy of MRgFUS CLT, a histologically and pathophysiologically based medial thalamotomy against chronic therapy-resistant trigeminal neuralgia.

OBJECTIVEIn addition to the well-recognized ventral intermediate nucleus (Vim) thalamotomy for the treatment of chronic therapy-resistant essential tremor (ET), an alternative approach targeting the posterior part of the subthalamus was proposed in the 1960s and early 1970s and then was reactualized as cerebellothalamic tractotomy (CTT) with the advent of MR-guided focused ultrasound (MRgFUS) surgery. The goal of this study was to improve target coverage and thus efficacy (i.e., tremor control and its consistency). The authors undertook a histological reappraisal of the CTT target and proposed a targeting strategy of the MRgFUS CTT based on 1) the MR visualization of the center of the red nucleus and 2) the application of preplanned target subunits realized with short sonications under thermal dose control. This study was aimed at demonstrating the efficacy and risk profile of this approach against chronic therapy-resistant ET.METHODSTen consecutive patients suffering from chronic therapy-resistant ET benefited from a unilateral MRgFUS CTT and were followed over the course of 1 year. Primary endpoints were subjective tremor relief, Clinical Rating Scale for Tremor (CRST) score, activities of daily living (ADL) score, and the hand function (HF) scores HF16 and HF32. Histological reappraisal of the target led the authors to propose a standardized targeting protocol for MRgFUS CTT. Thermal doses for 18 and 240 cumulative equivalent minutes at 43°C were calculated and correlated with intraoperative and 2 days postoperative T2-weighted MR images.RESULTSThe mean ± SD for the baseline CRST score was 48 ± 12; the score was 16 ± 7 at 3 months, and 17 ± 8 at 1 year. The mean tremor relief rated by the patients for the operated side was 95% after 2 days, 96% at 3 months, and 93% at 1 year. The mean HF16 was 11.0 ± 2.1 at baseline, 0.7 ± 0.7 at 3 months, and 0.8 ± 0.9 at 1 year (93% mean reduction). The minimum reduction for the HF16 at 1 year was 78%. There was a 51% reduction of the mean ADL score at 1 year. There was no bleeding or infection. Gait difficulties, only detectable on tandem gait, were increased in 3 patients and reduced in 2 patients at 1 year. There was no dysarthria.CONCLUSIONSThe authors’ results suggest that MRgFUS CTT is a very effective treatment option for therapy-resistant ET.

Additional co-authors: Jose Maria Fernandez-Palacios, Rosalina Gabriel, Roy E. Gereau, Rosemary G. Gillespie, Josef Greimler, David E.V. Harter, Tsurng-Juhn Huang, Severin D.H. Irl , Daniel Jeanmonod, Anke Jentsch, Christoph Kueffer, Sandra Nogue, Rudiger Otto, Jonathan Price, Maria M. Romeiras, Dominique Strasberg, Tod Stuessy, Jens-Christian Svenning, Ole R. Vetaas, Carl Beierkuhnlein

Du Pasquier, P.-E. & D. Jeanmonod (2016). Lectotypification of three species of Silene sect. Italicae (Rohrb.) Schischk. (Caryophyllaceae). Candollea 71: 19–22. In English, English and French abstracts. DOI : http://dx.doi.org/10.15553/c2016v711a4 Lectotypes are designated in Boissier's Flora Orientalis herbarium for Silene astartes C.I. Blanche ex Boiss., Silene galataea Boiss. and Silenea splendens Boiss., three species belonging to Silene sect. Italicae (Rohrb.) Schischk. (Caryophyllaceae). An authorship ambiguity about Silene astartes is also resolved.

Chronic neuropathic pain may require a neurosurgical treatment but for reasons that have not been fully explored yet a significant number of patients do not benefit from the intervention. We compared the resting EEG of 15 healthy controls to the EEG of 23 chronic neuropathic pain patients before and 12 months after treatment by the central lateral thalamotomy (CLT). A patient subgroup had a high (n = 14 pain relief (PR) = 50) and another subgroup a low (n = 9 PR < 50) postoperative PR. EEG spectral power and source localization of the high PR patients were normalized postoperatively. In contrast low PR patients showed postoperative maintenance of insular cingulate and prefrontal overactivities and their frustration values were positively correlated with cingulate and prefrontal activity. These findings demonstrate a normalizing effect of CLT on cortical activity and suggest that treatment resistance is associated with a frustration based dynamics. © 2011 Springer Science+Business Media LLC.

To study the mechanisms of chronic neurogenic pain, we compared the power spectra of the resting EEG of patients (n = 15, 38-75 years, median 64 years, 6 women) and healthy controls (n = 15, 41-71 years, median 60 years, 8 women). On an average, the patient group exhibited higher spectral power over the frequency range of 2-25 Hz, and the dominant peak was shifted towards lower frequencies. Maximal differences appeared in the 7-9 Hz band in all electrodes. Frontal electrodes contributed most to this difference in the 13-15 Hz band. Bicoherence analysis suggests an enhanced coupling between theta (4-9 Hz) and beta (12-25 Hz) frequencies in patients. The subgroup of six patients free from centrally acting medication showed higher spectral power in the 2-18 Hz frequency range. On an individual basis, the combination of peak height and peak frequency discriminated between patient and control groups: discriminant analysis classified 87% of all subjects correctly. After a therapeutic lesion in the thalamus (central lateral thalamotomy, CLT) we carried out follow-up for a subgroup of seven patients. Median pain relief was 70 and 95% after 3 and 12 months, respectively. The average EEG power of all seven patients gradually decreased in the theta band and approached normal values only after 12 months. The excess theta EEG power in patients and its decrease after thalamic surgery suggests that both EEG and neurogenic pain are determined by tightly coupled thalamocortical loops. The small therapeutic CLT lesion is thought to initiate a progressive normalization in the affected thalamocortical system, which is reflected in both decrease of EEG power and pain relief.

Jeanmonod, D. & A. Charpin (2017). The Burnat Herbarium (G-BU). Candollea 72 : 143–153. In French, English and French abstracts. DOI: http://dx.doi.org/10.15553/c2017v721a10 Emile Burnat (1828–1920) bequeathed his herbarium to the CJBG in 1911. It has been kept separate from the general collection G under the acronym G-BU. It consists of 1,572 boxes containing 219,843 specimens. It is divided into three parts : the European herbarium (1,169 boxes), the Maritime Alps herbarium (379 boxes) and the Thuret herbarium (24 boxes), also from the Maritime Alps. Burnat's personal collections and the ones of his collaborators reach 42,727 specimens and are mainly from the Maritime Alps, Switzerland and Corsica. The European herbarium is organized according to the Nyman Conspectus. The most original part is the Corsican collection (about 8,000 specimens), which served as a base for Briquet and Litardiere's Prodrome de la Flore Corse. The herbarium of the Maritime Alps, including some 55,000 specimens, is org...

This article analyzes partial data published in the “Flora Corsica” in order to characterize the Corsican vascular flora. These analyses focus on different aspects of the flora such as species richness, taxonomic distribution, abundance and life-forms at different vegetation belts, habitats and substrates. The results are compared with other geographic regions, particularly from the European Mediterranean and adjacent areas. The decrease of species richness with an increase of altitude as well as the sharp decrease of Fabaceae has been confirmed. Regarding the biological spectrum, the decrease of the therophytes with an increase of altitude is obvious and compensated by the increase of the hemicryptophytes. On Corsica several peculiarities have been highlighted in the different ecological compartments: 1. the littoral and the cryo-oromediterranean belts appear to be very different from the others in many features; 2. the rocky habitats are shown to be especially important for the diversity of families such as Poaceae and Caryophyllaceae; 3. calcareous areas are shown to be extremely important for the alpha diversity as well as for the restricted range taxa. Finally, the specificity of the flora growing on the ultramafic outcrops is confirmed and emphazised.

We investigate the genetic diversity and demographic patterns of the Silene paradoxa group from section Siphonomorpha, which includes the three species S. paradoxa, S. fruticosa and S. aristidis. Eight additional taxa, belonging to the same section, were also included in this study for comparative purposes: S. nutans, S. viridiflora and six species of the italica complex. The nuclear internal transcribed spacer (ITS) and the two chloroplast spacers trnH-psbA and trnS-trnG show that the paradoxa group constitutes a separate genetic lineage within section Siphonomorpha and includes three well-differentiated species, characterized by different levels of genetic diversity and demographic histories. All three species showed specific haplotypes and ITS variants, intraspecific variation and contrasting demographic histories. S. paradoxa probably followed a demographic expansion scenario, whereas S. fruticosa and S. aristidis most likely went through spatial expansions in the past. Chasmophyte species and species from open rocky habitats are found in both the paradoxa group and the italica complex, suggesting that the switch between the chasmophytic and open habitats occurred at least twice in the Siphonomorpha section.

Bungener, P. & D. Jeanmonod (2019). The Brothers Soleirol, a centuries-long history of a confusion on a collector in Corsica. Candollea 74: 209–216. In French, English & French abstracts.Soleirol is a famous botanical collector well known for his plant collections in Corsica in the 1820's. Many scientific names of taxa have been dedicated to him. Although his herbarium specimens and letters have been signed by his surname alone and without his first name, the botanical tradition has given him the surname of Joseph-Francois (1781–1863). Our investigation shows that this botanist is in fact Henri-Augustin (1792–1860), the younger brother of Joseph-Francois. That conclusion is drawn on the analysis of his herbarium specimens, botanical literature, correspondence and biographical accounts. The Brothers Soleirol have followed a similar career in the French Army and had the same interests for art and botany. These similar ways of life have subsequently caused the confusion of their surnames. Our research shows that Henry-Augustin was the only one who collected plants in Corsica between 1820 and 1823 and visited about sixty localities from Cap Corse to Bonifacio through the large mountain ranges. As an important plant collector for Corsica, Soleirol has collected more than 5000 specimens that he has distributed or exchanged with other botanists. This paper highlights the activity of an amateur botanist at the beginning of the XIXth century. It honors Henry Augustin for his work after more than one century of confusion with his brother.

Les recentes avancees de la technologie des ultrasons focalises permettent depuis 2008 la realisation de lesions cerebrales therapeutiques sans incision avec une ­precision et une securite jamais atteintes par les techniques stereotaxiques avec penetration cerebrale. Elle permet actuellement de proposer aux patients atteints de tremblement essentiel, de la maladie de Parkinson ou de douleurs neuropathiques, chroniques et refractaires aux traitements conservateurs, une alternative a la ­stimulation cerebrale profonde.

Die neuen Entwicklungen der intrakraniellen fokussierten Ultraschalltechnologie erlauben seit 2008 die Durchfuhrung von therapeutischen, inzisionslosen Eingriffen am Gehirn mit einer Prazision und Sicherheit, die durch stereotaktische Methoden mit Penetration des Gehirns niemals erreicht werden konnten. Sie bietet Patienten, die unter chronischen und therapieresistenten neurologischen Erkrankungen wie essentiellem Tremor, Morbus Parkinson oder neuropathischen Schmerzen leiden, eine Alternative zur Tiefenhirnstimulation.

Silene astartes C.I. Blanche ex Boiss., Fl. Orient. Suppl.: 102. 1888. Lectotypus (designated here): Lebanon . Prov. Mount-Lebanon: Djeba��l, ruines d���AFka, VI-VII.1880, fl. & Fr., Blanche 55 (G-BOIS [G00330604]!; isolecto-: BEI!, G [G00341654]!) (Fig. 1). Notes. ��� Boissier (1888) published S. astartes in the ���Supplementum oF the Flora Orientalis���. He wrote ��� S. astartes (Blanche in litt.)��� beFore the Latin description. &ENG;e mention oF Blanche as the author ���in litt.��� by Boissier has been interpreted in different ways in the literature. Floras oF Lebanon have cited only C.I. Blanche as the author oF the species (sometimes with the mention ���in Boiss.���; Post, 1896, 1932; Thi��baut, 1936; Mouterde, 1966; Tohm�� & Tohm��, 2007), whereas BouloumoY (1930) interpreted the authorship as ���Boiss. et B.��� [Boiss. & C.I. Blanche]. In the Boissier���s Herbarium oF the ���Flora Orientalis��� (G-BOIS), Blanche 55 contains a handwritten note by Blanche himselF with a Latin description oF the species (Fig. 1). However this description differs considerably From the protologue where Boissier published a new and more complete description by validating the name (Boissier, 1888: 102). We thereFore ascribe Boissier as the author oF S. astartes in accordance with Greuter et al. (1984) and not as C.I. Blanche as mentioned in the latest flora oF Lebanon treatment (Tohm�� & Tohm��, 2007). Boissier (1888) clearly cited two gatherings in the protologue: ���Hab. in Libano supra Djebail ad minas AFka (Bl.!)��� and ���ad Ain SuFar (Peyron!)���. Only Blanche 55 [G00330604] is present in G-BOIS. We Found three duplicates oF the Peyron collection at G and one at P. Each oF them bears the locality ���Ain SuFar��� and are dated June 11, 1882. Two oF them have the collection number 1379 mentioned [G00341656, P04987226]) and two [G00341655, G00341657] without any number. All these collections have a glandular-pubescent calyx and match Fully with S. italica (L.) Pers. and not with S. astartes, which has a calyx always glabrous. &ENG;ereFore, we choose Blanche 55 housed at G-BOIS as the lectotype, which is the only material present at G-BOIS and exclude the remaining syntypes From S. astartes., Published as part of Pierre-Emmanuel Du Pasquier & Daniel Jeanmonod, 2016, Lectotypification of three species of Silene sect. Italicae (Rohrb.) Schischk. (Caryophyllaceae), pp. 19-22 in Candollea 71 (1) on page 21, DOI: 10.15553/c2016v711a4, http://zenodo.org/record/162047, {"references":["Boissier, P. E. (1888). Fl. Orient. Suppl. Geneve.","Post, G. E. (1896). Fl. Syria. Syrian Protestant College, Beirut.","Post, G. E. (1932). Fl. Syria 1. 2 nd ed. American Press, Beirut.","ThiEbaut, J. (1936). Fl. Lib. - Syr. 1. Le Caire.","Mouterde, P. S. J. (1966). Nouv. Fl. Liban. 1. Edition de l'Imprimerie Catholique, Beyrouth.","TohmE, G. & H. TohmE (2007). Ill. Fl. Lebanon. CNRS, Beirut","BouloumoY, L. (1930). Fl. Liban. Vigot Freres.","Greuter, W., H. M. Burdet & G. Long (ed.) (1984). Med-Checklist. A critical inventory of vascular plants of the circum-mediterranean countries. Vol 1. Conservatoire et Jardin botaniques de la Ville de Geneve."]}

Silene galataea Boiss., Fl. Orient. Suppl.: 102. 1888. Lectotypus (designated here): Cyprus . Prov. Tro��dos: circa Galata, 15.VI.1880, Fl. & Fr., Sintenis U Rigo 768 (G-BOIS [G00330606]!; isolecto-: G-BOIS [G00330606]!, K [K000728598, K000728599] images seen, LD [LD1403097, LD1403157] images seen, P [P05019189, P05396106]!) (Fig. 2). Notes. ��� A single gathering was designated For S. galataea (Sintenis U Rigo 768) by Boissier (1888). Two sheets oF this collection are housed in G-BOIS, on which two and one specimens are mounted respectively, all clearly labelled. &ENG;ese specimens apparently correspond to distinct individuals, although it is not clearly obvious on the first sheet. We know that Boissier���s material is not always homogenous and corresponds sometimes to diFFerent species (Jeanmonod, 1985), especially in Silene L. with numerous convergences and potentially cryptic species. For this reason we preFer to fix the morphology oF this species by designating a single plant as lectotype. We thereFore designate the single specimen in G-BOIS mounted on the second sheet as lectotype because it is the most complete specimen and the determination bears Boissier���s handwriting (Fig. 2). &ENG;e two other specimens in G-BOIS are thereFore considered as isolectotypes as the remaining duplicates distributed in various herbaria., Published as part of Pierre-Emmanuel Du Pasquier & Daniel Jeanmonod, 2016, Lectotypification of three species of Silene sect. Italicae (Rohrb.) Schischk. (Caryophyllaceae), pp. 19-22 in Candollea 71 (1) on page 21, DOI: 10.15553/c2016v711a4, http://zenodo.org/record/162047, {"references":["Boissier, P. E. (1888). Fl. Orient. Suppl. Geneve.","Jeanmonod, D. (1985). Silene amana Boiss.: une conFusion. Candollea 40: 1 - 3."]}

Background Already in the late 1960s and early 1970s, targeting of the “posterior subthalamic area (PSA)” was explored by different functional neurosurgical groups applying the radiofrequency (RF) technique to treat patients suffering from essential tremor (ET). Recent advances in magnetic resonance (MR)-guided focused ultrasound (MRgFUS) technology offer the possibility to perform thermocoagulation of the cerebellothalamic fiber tract in the PSA without brain penetration, allowing a strong reduction of the procedure-related risks and increased accuracy. We describe here the first results of the MRgFUS cerebellothalamic tractotomy (CTT). Methods Twenty-one consecutive patients suffering from chronic (mean disease duration 29.9 years), therapy-resistant ET were treated with MRgFUS CTT. Three patients received bilateral treatment with a 1-year interval. Primary relief assessment indicators were the Essential Tremor Rating Scale (Fahn, Tolosa, and Marin) (ETRS) taken at follow-up (3 months to 2 years) with accent on the hand function subscores (HF16 for treated hand and HF32 for both hands) and handwriting. The evolution of seven patients with HF32 above 28 points over 32 (group 1) differentiated itself from the others’ (group 2) and was analyzed separately. Global tremor relief estimations were provided by the patients. Lesion reconstruction and measurement of targeting accuracy were done on 2-day post-treatment MR pictures for each CTT lesion. Results The mean ETRS score for all patients was 57.6 ± 13.2 at baseline and 25.8 ± 17.6 at 1 year (n = 10). The HF16 score reduction was 92 % in group 2 at 3 months and stayed stable at 1 year (90 %). Group 1 showed only an improvement of 41 % at 3 months and 40 % at 1 year. Nevertheless, two patients of group 1 treated bilaterally had an HF16 score reduction of 75 and 88 % for the dominant hand at 1 year after the second side. The mean patient estimation of global tremor relief after CTT was 92 % at 2 days and 77 % at 1-year follow-up. Conclusions CTT with MRgFUS was shown to be an effective and safe approach for patients with therapy-refractory essential tremor, combining neurological function sparing with precise targeting and the possibility to treat patients bilaterally.

Object Recent technological developments open the field of therapeutic application of focused ultrasound to the brain through the intact cranium. The goal of this study was to apply the new transcranial magnetic resonance imaging–guided focused ultrasound (tcMRgFUS) technology to perform noninvasive central lateral thalamotomies (CLTs) as a treatment for chronic neuropathic pain. Methods In 12 patients suffering from chronic therapy-resistant neuropathic pain, tcMRgFUS CLT was proposed. In 11 patients, precisely localized thermal ablations of 3–4 mm in diameter were produced in the posterior part of the central lateral thalamic nucleus at peak temperatures between 51°C and 64°C with the aid of real-time patient monitoring and MR imaging and MR thermometry guidance. The treated neuropathic pain syndromes had peripheral (5 patients) or central (6 patients) origins and covered all body parts (face, arm, leg, trunk, and hemibody). Results Patients experienced mean pain relief of 49% at the 3-month follow-up (9 patients) and 57% at the 1-year follow-up (8 patients). Mean improvement according to the visual analog scale amounted to 42% at 3 months and 41% at 1 year. Six patients experienced immediate and persisting somatosensory improvements. Somatosensory and vestibular clinical manifestations were always observed during sonication time because of ultrasound-based neuronal activation and/or initial therapeutic effects. Quantitative electroencephalography (EEG) showed a significant reduction in EEG spectral overactivities. Thermal ablation sites showed sharply delineated ellipsoidal thermolesions surrounded by short-lived vasogenic edema. Lesion reconstructions (18 lesions in 9 patients) demonstrated targeting precision within a millimeter for all 3 coordinates. There was 1 complication, a bleed in the target with ischemia in the motor thalamus, which led to the introduction of 2 safety measures, that is, the detection of a potential cavitation by a cavitation detector and the maintenance of sonication temperatures below 60°C. Conclusions The authors assert that tcMRgFUS represents a noninvasive, precise, and radiation-free neurosurgical technique for the treatment of neuropathic pain. The procedure avoids mechanical brain tissue shift and eliminates the risk of infection. The possibility of applying sonication thermal spots free from trajectory restrictions should allow one to optimize target coverage. The real-time continuous MR imaging and MR thermometry monitoring of targeting accuracy and thermal effects are major factors in optimizing precision, safety, and efficacy in an outpatient context.

This article summarizes and analyses some of the data published in Flora Corsica (Jeanmonod & Gamisans, 2007) in order to characterize the alien vascular plant flora of the island. The data analysed focus on different aspects of the alien flora such as diversity (species richness), abundance, lifeforms, vegetation belts, habitats and biogeographical origins. The results show that the alien species richness is currently high, representing 16.5% of the total flora, amongst which 37.5% are naturalized. The penetration of this flora occurs mainly at lower altitudes, and is still weak or absent in the higher altitude vegetation belts whereas it has increased over time within natural closed habitats. Over the last 11 years, the species richness of xenophytes has increased by 18.1%, which corresponds to an increase of 23.0% of the naturalized plants. Moreover, 24.8% of the alien taxa have increased in abundance. A scenario highlighting the trends of the introduced flora, and that includes issues of native biodiversity conservation, is proposed based on the results. The special case of invasive species is also considered, and their exponential increase on Corsica is highlighted. Other aspects of the alien flora, such as its taxonomic spectrum and biogeographical origins, are also analysed and are, whenever possible, compared with those of other geographical regions, particularly from the Mediterranean (Sardinia, Balearic Islands) and Continental Europe.

Jeanmonod, D., A. Schlussel & J. Gamisans (2011). Analysis of the Corsican flora: biological aspects. Candollea 66: 5–25. In French, English and French abstracts.This article summarizes and analyzes some of the data published in “Flora Corsica”, in order to characterize the Corsican flora (vascular plants). This analysis focuses on different aspects such as diversity (species richness, richest families), abundance (global, in each vegetation belt, in each habitat and substrate types), longevity and life forms (in all the studied area, in each vegetation belt) and phenology (flowering curves). The results are, whenever possible, compared with those of other geographic regions, particularly from the Mediterranean. They help outlining typical Mediterranean patterns, characterizing the Corsican vegetation belts, and identifying characteristics specifically related to the flora of Corsica.

During stereotactic functional neurosurgery, stimulation procedure to control for proper target localization provides a unique opportunity to investigate pathophysiological phenomena that cannot be addressed in experimental setups. Here we report on the distribution of response modalities to 487 intraoperative thalamic stimulations performed in 24 neurogenic pain (NP), 17 parkinsonian (PD) and 10 neuropsychiatric (Npsy) patients. Threshold responses were subdivided into somatosensory, motor and affective, and compared between medial (central lateral nucleus) and lateral (ventral anterior, ventral lateral and ventral medial) thalamic nuclei and between patients groups. Major findings were as follows: in the medial thalamus, evoked responses were for a large majority (95%) somatosensory in NP patients, 47% were motor in PD patients, and 54% affective in Npsy patients. In the lateral thalamus, a much higher proportion of somatosensory (83%) than motor responses (5%) was evoked in NP patients, while the proportion was reversed in PD patients (69% motor vs. 21% somatosensory). These results provide the first evidence for functional cross-modal changes in lateral and medial thalamic nuclei in response to intraoperative stimulations in different functional disorders. This extensive functional reorganization sheds new light on wide-range plasticity in the adult human thalamocortical system.

Patients with severe and chronic neurogenic pain are known to exhibit excess EEG oscillations in the 4- to 9-Hz theta frequency band in comparison with healthy controls. The generators of these excess EEG oscillations are localized in the cortical pain matrix. Since cortex and thalamus are tightly interconnected anatomically, we asked how thalamic activity and EEG are functionally related in these patients. During the surgical intervention in ten patients with neurogenic pain, local field potentials were recorded from the posterior part of the central lateral nucleus (CL). The highest thalamocortical coherence was found in the 4- to 9-Hz theta frequency band (median 7.7 Hz). The magnitude of thalamocortical theta coherence was comparable to the magnitude of EEG coherence between scalp electrode pairs. Median thalamocortical theta coherence was 27%, reached up to 68% and was maximal with frontal midline scalp sites. The observed high thalamocortical coherence underlines the importance of the thalamus for the synchronization of scalp EEG. We discuss the pathophysiology within the framework of a dysrhythmic thalamocortical interplay, which has important consequences for the choice of therapeutic strategy in patients with chronic and severe forms of neurogenic pain.

Oscillatory and coherent EEG activity is increasingly recognized as a fundamental hallmark of cortical integrative functions. We aimed to study deviations from the norm of different resting EEG parameters in Parkinson's disease (PD) patients. We compared spectral parameters of the resting EEG of PD patients (n=24, median age 67 years) to those of healthy controls (n=34, median age 62 years). On average, the patient group exhibited higher spectral power over the frequency range of 2-100 Hz, and the dominant peak was shifted towards lower frequencies. Maximal differences appeared in the 6-9 Hz theta band in all electrodes. Frontal electrodes contributed most to this difference in the 4-6 Hz theta, 12-18 Hz beta and 30-45 Hz gamma bands. On an individual basis, the combination of six spectral power band parameters discriminated between patient and control groups and 72% of all subjects were classified correctly. Using LORETA source analysis, the generators of this power difference were localized to fronto-insulo-temporal cortical areas in the theta and beta bands, and to interhemispheric frontal (supplementary motor area, SMA) and cingulate areas in the 30-45 Hz gamma band. We calculated spectral coherence between electrode pairs in a frontal, central and parietal region of interest (ROI). In the frontal ROI, coherence was enhanced significantly in the patient group in the theta, high beta and gamma bands. In the parietal ROI, patients showed lower coherence around 10 Hz. We demonstrate a deviation from the norm of different resting EEG parameters in PD patients. This evidence can be integrated in the context of a pathophysiological chain reaction initiated in the substantia nigra and resulting in a cortical aberrant dynamics rooted in enhanced dysrhythmic thalamocortical interactions.

JEANMONOD, D., Y. NACIRI, A. SCHLUSSEL & J. GAMISANS (20 15). Floristic analyses of the Corsican flora : biogeographical origin and endemism. Candollea 70 : 21-41. In English. English and French abstracts. DOI : http://dx.doi.org/10.15553/c2015v701a3 This article discusses various aspects of the biogeographical origin and endemism of the Corsican flora based on data retrieved from “Flora Corsica” project. It focuses on species richness, taxonomy, life forms, taxa abundance, distribution in vegetation belts, habitats and substrate types. The results are compared to other geographic regions, particularly Mediterranean ones. These data show that in Corsica the species of Mediterranean origin are slightly more numerous than those of Holarctic origin. It is surprising that the Holarctic elements start to dominate at low altitude in the supramediterranean belt. The endemic flora (12.7 %) shows distribution patterns often distinct from those of the non-endemic native flora, particularly regarding taxonomy, biological types and altitudinal distributions. The rates of hemicryptophytes and chamaephytes are for instance higher for the former compared to the latter while it is the reverse for therophytes. These rates are quite similar to those recorded in Sardinia, but rather different from those of other Mediterranean islands. More unexpected is the abundance pattern of endemic species which is quite similar to that of non-endemic ones. However, strictly endemic Corsican species are generally rarer than subendemics. The number of endemic species increases from the coast to the montane belt and then decreases in the upper belts. The percentage of endemic species, meanwhile, regularly increases from the thermomediterranean belt to the alpine one where it reachs a maximum of 43.1 %. The endemic flora also shows a wider altitudinal spectrum than other native species. The distribution of endemic species in the different Corsican habitats is slightly different from the one recorded for the indigeneous taxa. Endemics are however preferentially found in rocky habitats, but without any preference for a particular substrate. In the endemic flora, the Mediterranean origin is predominant but this trend is more marked in subendemics. The strict Corsican endemics have a mostly Holarctic origin and are more often found at high altitudes. These results shed light on the specificity of the Corsican endemic flora and should help the management of endemic species. Resume

These “notes” deal with 110 noteworthy taxa amongst which 21 are new to the island's flora. One of these taxa is native: Reseda alba subsp. hookeri and 20 are introduced: Abies pinsapo, Acer ×coriaceum, Albizia julibrissin, Arundo micrantha, Azolla filiculoides, Bolboschoenus laticarpus, Digitaria ciliaris, Digitaria violascens, Eucalyptus camaldulensis, E. globulus, Genista januensis subsp. lydia, Hedera helix subsp. maroccana, Morus kagayamae, Oenothera rosea, Paspalum vaginatum, Puccinellia festuciformis subsp. lagascana, Silene fuscata, Solanum mauritianum, Veronica filiformis and Vitis riparia × V. rupestris. The presence of Aegilops ventricosa and Legousia speculum-veneris is presently confirmed. However Carex praecox, Eleocharis quinqueflora, Herniaria hirsuta subsp. cinerea, Juncus acutiflorus and Juncus compressus must be deleted from the Corsican Flora due to their confusion with other related taxa. New localities are given for 48 taxa considered as “very rare” (RR) out of which 10 become “rare” (R) on the one hand, and for 23 taxa considered to be “rare” (R) out of which 12 change their status from “rare” to “not common” (PF) or “localised” (LOC), on the other. Finally, the data published for the 12 remaining taxa (considered as “localised” (LOC) or “not common” (PF) constitute a considerable increase of our knowledge about their distribution. The new sites often correspond to new sectors for these taxa. Fourteen out of 110 taxa are endemic, 11 are part of the red list and 44 are xenophytic species. A distribution map is also provided for Carex extensa and Cerastium siculum.

Functional brain imaging of pain over the last years has provided insight into a distributed anatomical matrix involved in pain processing which includes multiple cortical areas. EEG/MEG-based imaging studies have mostly relied on settings of evoked nociception. We report here the spontaneous presence of enhanced activations in the pain matrix of the patient group on the basis of continuous EEG and functional Low Resolution Electromagnetic Tomography (LORETA) from 16 chronic neurogenic pain patients and 16 healthy controls. These overactivations occurred predominantly within the high theta (6-9 Hz) and low beta frequency ranges (12-16 Hz). Theta and beta overactivations were localized to multiple pain-associated areas, primarily to insular (IC), anterior cingulate (ACC), prefrontal, and inferior posterior parietal cortices, as well as to primary (S1), secondary (S2), and supplementary somatosensory (SSA) cortices. After a therapeutic lesion in the thalamus (central lateral thalamotomy, CLT), we followed a subgroup of 6 patients. Twelve months after surgery, activation in cingulate and insular cortices was significantly reduced. The presence of rhythmic processes in multiple, partially overlapping areas of the cortical pain matrix concur with the concept of thalamocortical dysrhythmia (TCD) that predicts increased thalamocortical low and high frequency oscillations ensuing from thalamic desactivation. These spontaneous, ongoing, frequency-specific overactivations may therefore serve as an anatomo-physiological hallmark of the processes underlying chronic neurogenic pain.

The premotor cortex of macaque monkeys is currently subdivided into at least six different subareas on the basis of structural, hodological and physiological criteria. To determine the degree of divergence/convergence of thalamocortical projections to mesial [supplementary motor area (SMA)-proper and pre-SMA] and lateral (PMd-c, PMd-r, PMv-c and PMv-r) premotor (PM) subareas, quantitative analyses were performed on the distribution of retrograde labelling after multiple tracer injections in the same animal. The results demonstrate that all PM and SMA subareas receive common inputs from several thalamic nuclei, but the relative contribution of these nuclei to thalamocortical projections differs. The largest difference occurs between subareas of SMA, with much greater contribution from the mediodorsal (MD) and area X, and a smaller contribution from the ventral lateral anterior (VLa) and ventral part of the ventral lateral posterior (VLpv) to pre-SMA than to SMA-proper. In PM, differences between subareas are less pronounced; in particular, all receive a significant contribution from MD, the ventral anterior (VApc) and area X. However, there are clear gradients, such as increasing projections from MD to rostral, from VLa and VLpv to caudal, and from dorsal VLp (VLpd) to dorsal premotor subareas. Intralaminar nuclei provide widespread projections to all premotor subareas. The degree of overlap between thalamocortical projections varies among different PM and SMA subareas and different sectors of the thalamus. These variations, which correspond to different origin and topography of thalamocortical projections, are discussed in relation to functional organizations at thalamic and cortical levels.

Background Radiofrequency (RF) subthalamotomies have been proposed since the 1960s to treat patients suffering from Parkinson's disease (PD). Recently, the magnetic resonance (MR)-guided focused ultrasound technology (MRgFUS) offers the possibility to perform subthalamic thermocoagulations with reduced risks and optimized accuracy. We describe here the initial results of the MRgFUS pallidothalamic tractotomy (PTT), an anatomical and physiological update of the earlier subthalamotomies. Methods Thirteen consecutive patients suffering from chronic (mean disease duration 9.7 years) and therapy-resistant PD were treated unilaterally with an MRgFUS PTT. Primary relief assessment indicators were the score reduction of the Unified Parkinson Disease Rating Scale (UPDRS) and the patient estimation of global symptom relief (GSR) taken at 3 months follow-up. Final temperatures at target were between 52°C and 59°C. The MR examinations were performed before the treatment, 2 days and 3 months after it. The accuracy of the targeting was calculated on 2 days post-treatment MR pictures for each PTT lesion. Results The first four patients received a PTT using the lesional parameters applied for thalamotomies. They experienced clear-cut recurrences at 3 months (mean UPDRS relief 7.6%, mean GSR 22.5%), and their MR showed no sign of thermal lesion in T2-weighted (T2w) images. As a consequence, the treatment protocol was adapted for the following nine patients by applying repetition of the final temperatures 4 to 5 times. That produced thermocoagulations of larger volumes (172 mm3 against 83 mm3 for the first four patients), which remained visible at 3 months on T2w images. These nine patients enjoyed a mean UPDRS reduction of 60.9% and a GSR of 56.7%, very close to the results obtained with radiofrequency lesioning. The targeting accuracy for the whole patient group was 0.5, 0.5, and 0.6 mm for the anteroposterior (AP), mediolateral (ML), and dorsoventral (DV) dimensions, respectively. Conclusions This study demonstrated the feasibility, safety, and accuracy of the MRgFUS PTT. To obtain similar results as the ones of RF PTT, it was necessary to integrate the fact that white matter, in this case, the pallidothalamic tract, requires repeated thermal exposition to achieve full lesioning and thus full therapeutic effect.

In 1997, Morel, Magnin, and Jeanmonod presented a microscopic stereotactic atlas of the human thalamus. Parcellations of thalamic nuclei did not only use cyto- and myeloarchitectonic criteria, but were additionally corroborated by staining for calcium-binding proteins, which bears functional significance. The atlas complies with the Anglosaxon nomenclature elaborated by Jones and the data were sampled in three orthogonal planes in the AC-PC reference space. We report on the generation of three-dimensional digital models of the thalamus based on the three sets of sections (sagittal, horizontal, and frontal). Spatial differences between the three anatomical specimens were evaluated using the centers of gravity of 13 selected nuclei as landmarks. Subsequent linear regression analysis yielded equations, which were used to normalize the frontal and horizontal digital models to the sagittal one. The outcome is an internally consistent Canonical Model of Morel's atlas, which minimizes the linear component of the variability between the three sectioned anatomical specimens. In addition, we demonstrate the feasibility of the atlas-to-MRI registration in conjunction with on-line visualization of the trajectory in the digital models.

Spontaneous magnetoencephalographic activity was recorded in awake, healthy human controls and in patients suffering from neurogenic pain, tinnitus, Parkinson's disease, or depression. Compared with controls, patients showed increased low-frequency θ rhythmicity, in conjunction with a widespread and marked increase of coherence among high- and low-frequency oscillations. These data indicate the presence of a thalamocortical dysrhythmia, which we propose is responsible for all the above mentioned conditions. This coherent θ activity, the result of a resonant interaction between thalamus and cortex, is due to the generation of low-threshold calcium spike bursts by thalamic cells. The presence of these bursts is directly related to thalamic cell hyperpolarization, brought about by either excess inhibition or disfacilitation. The emergence of positive clinical symptoms is viewed as resulting from ectopic γ-band activation, which we refer to as the “edge effect.” This effect is observable as increased coherence between low- and high-frequency oscillations, probably resulting from inhibitory asymmetry between high- and low-frequency thalamocortical modules at the cortical level.

On the basis of the new edition (October 1993) of the «Checklist of the vascular plants of Corsica» an evaluation of the knowledge on the flora of Corsica has been conducted. The total number of taxa, their number in each vegetation belt and their phytogeographical range are given. The affinities of the flora of Corsica are discussed. The interest of this flora lies not only in a high percentage of endemics but as well in the occurence of sometimes very small populations belonging to species being at the limit of their distribution area. Relatively to other north mediterranean areas, this flora is considered to be quite well preserved. However, due to the extinction of several populations, especially in coastal areas with high human pressure, urgent actions must be taken., Les auteurs dressent le bilan des connaissances sur la flore corse à partir de la nouvelle édition (octobre 1993) du Catalogue des plantes vasculaires de la Corse. Le nombre total de taxons, leur nombre par étage de végétation, le spectre phytogéographique sont notamment précisés. Les affinités de la flore corse sont rappelées. L’intérêt patrimonial de cette flore réside dans le nombre important de taxons endémiques corses, cyrno-sardes ou autres, mais aussi dans les populations d’espèces en limite d’aire en Corse, populations parfois très réduites. Relativement à celui des flores d’autres domaines nord-méditerranéens, l’état de conservation de la flore corse peut être considéré comme assez bon. Néanmoins, des disparitions notables de populations ont déjà eu lieu, tout particulièrement dans les régions littorales soumises à une forte pression humaine et des mesures urgentes sont à prendre dans certains cas., Gamisans Jacques, Jeanmonod Daniel. La flore de Corse : bilan des connaissances, intérêt patrimonial et état de conservation. In: Ecologia mediterranea, tome 21 n°1-2, 1995. Connaissance et conservation de la flore des îles de la Méditerrannée. Ajaccio, Corse, France (5-8 octobre 1993) pp. 135-148.