bluuebunny/crossref_metadata_2025_split huggingface dataset:
Late Glacial, Early Holocene and Late Holocene life at the interface of a distinct landscape — relationship of humans and environments in the Sub-Carpathian region (N Hungary)
Authors: Bácsmegi Gábor , Sümegi Pál , Törőcsik Tünde 
Published: December 2012

Abstract
Relationships between the communities and environment surrounding these communities can be disclosed by the application of different archeological, geological and environmental historical methods. This includes the deployment of numerous tools in scientific investigation including the application of chronological, sedimentological, geochemical and paleoecological analytical methods on sequences accumulated in historical catchment basins of peat-bog. The Nádas-tó at Nagybárkány is a small peatbog in the northern part of Hungary, on the Sub-Carpathian region. The formation of the lake can be traced back to the Late Glacial period. The sediments deposited in the lakebed provide a record of climatic and hydrologic changes. A higher water level could be demonstrated from the Late Glacial to the Mid-Holocene, when the reed-beds covered a small area only. This was followed by a hiatus spanning ca. 4400 years, caused by the deepening and cleaning of the lakebed during the Late Iron / Imperial Age, between 2100 - 1900 cal BP years. After this change the water level decreased and the water quality was more eutrophic. A reed-bed evolved around the lake. Paludification started with a bulrush floating mat phase at the close of the Middle Age, ca. 1500 cal AD years. The endowments and settlement pattern persisted from the Neolithic onwards until the terminal Modern Age, when measures aimed to ordain the area substantially altered the natural landscape. Although some anthropogenic disturbances can be reconstructed in the development of the peatland, some climatic effects and authogenic processes might be separated by paleoecological analyses.
Erratum to: Geotechnical and mineralogical properties of weak rocks from Central Greece
Authors: Ilia Ioanna , Rozos Dimitrios , Perraki Theodora , Tsangaratos Paris 
Published: December 2012

Abstract
The original version of this article was published in Central European Journal of Geosciences volume 1, issue 4 (2009), pp 431–442, DOI:10.2478/v10085-009-0029-0. Unfortunately the original version of this article contains mistakes in authors names which we correct here. Editorial staff of the journal apologise for any inconvenience that may result from the oversight.
Physical Exercise for Patients Undergoing Hematopoietic Stem Cell Transplantation: Systematic Review and Meta-Analyses of Randomized Controlled Trials
Authors: van Haren Inge E.P.M. , Timmerman Hans , Potting Carin M. , Blijlevens Nicole M.A. , Staal J. Bart , Nijhuis-van der Sanden Maria W.G. 
Published: December 2012

Background
The treatment-related burden for patients undergoing hematopoietic stem cell transplantation (HSCT) may be relieved by physical exercises.

Purpose
The purpose of this study was to summarize and analyze the evidence provided by randomized controlled trials (RCTs) on physical exercise interventions among patients with cancer undergoing HSCT.

Data Sources
PubMed, CINAHL, EMBASE, the Cochrane Library, and PEDro were searched for relevant RCTs up to October 1, 2011.

Study Selection
Two reviewers screened articles on inclusion criteria and indentified relevant RCTs.

Data Extraction
Two authors assessed the selected articles for risk of bias. Data extraction was performed by 1 reviewer. Meta-analyses were undertaken to estimate the outcomes quality of life (QOL), psychological well-being and distress, and fatigue.

Data Synthesis
Eleven studies were included, with study populations consisting of recipients undergoing either an allogeneic or autologous HSCT (n=734). Four studies had low risk of bias. The exercise interventions were performed before, during, and after hospitalization for the HSCT. Different exercise programs on endurance, resistance and/or activities of daily living training, progressive relaxation, and stretching were used. Meta-analyses showed that exercise during hospitalization led to a higher QOL (weighted mean difference=8.72, 95% confidence interval=3.13, 14.31) and less fatigue (standardized mean difference=0.53, 95% confidence interval=0.16, 0.91) in patients with an allogeneic HSCT at the moment of discharge from the hospital. No marked effects were found for psychological well-being and distress. Individual study results suggested significant positive effects on QOL, fatigue, psychological well-being and distress, and physical functioning.

Limitations
Prevalent shortcomings in the included studies were the heterogeneity among studies and the lack of blinding of participants, personnel, and outcome assessment.

Conclusions
The results suggest that recipients of HSCT may benefit from physical exercise.
Needs assessment for simulation training in neuroendoscopy: a Canadian national survey
Authors: Haji Faizal A. , Dubrowski Adam , Drake James , de Ribaupierre Sandrine 
Published: December 2012

Object
In recent years, dramatic changes in surgical education have increased interest in simulation-based training for complex surgical skills. This is particularly true for endoscopic third ventriculostomy (ETV), given the potential for serious intraoperative errors arising from surgical inexperience. However, prior to simulator development, a thorough assessment of training needs is essential to ensure development of educationally relevant platforms. The purpose of this study was to conduct a national needs assessment addressing specific goals of instruction, to guide development of simulation platforms, training curricula, and assessment metrics for ETV.

Methods
Canadian neurosurgeons performing ETV were invited to participate in a structured online questionnaire regarding the procedural steps for ETV, the frequency and significance of intraoperative errors committed while learning the technique, and simulation training modules of greatest potential educational benefit. Descriptive data analysis was completed for both quantitative and qualitative responses.

Results
Thirty-two (55.2%) of 58 surgeons completed the survey. All believed that virtual reality simulation training for ETV would be a valuable addition to clinical training. Selection of ventriculostomy site, navigation within the ventricles, and performance of the ventriculostomy ranked as the most important steps to simulate. Technically inadequate ventriculostomy and inappropriate fenestration site selection were ranked as the most frequent/significant errors. A standard ETV module was thought to be most beneficial for resident training.

Conclusions
To inform the development of a simulation-based training program for ETV, the authors have conducted a national needs assessment. The results provide valuable insight to inform key design elements necessary to construct an educationally relevant device and educational program.
Hearing preservation in patients with vestibular schwannoma treated with Gamma Knife surgery
Authors: Baschnagel Andrew M. , Chen Peter Y. , Bojrab Dennis , Pieper Daniel , Kartush Jack , Didyuk Oksana , Naumann Ilka C. , Maitz Ann , Grills Inga S. 
Published: December 2012

Object
Hearing loss after Gamma Knife surgery (GKS) in patients with vestibular schwannoma has been associated with radiation dose to the cochlea. The purpose of this study was to evaluate serviceable hearing preservation in patients with VS who were treated with GKS and to determine if serviceable hearing loss can be correlated with the dose to the cochlea.

Methods
Forty patients with vestibular schwannoma with serviceable hearing were treated using GKS with a median marginal dose of 12.5 Gy (range 12.5–13 Gy) to the 50% isodose volume. Audiometry was performed prospectively before and after GKS at 1, 3, and 6 months, and then every 6 months thereafter. Hearing preservation was based on pure tone average (PTA) and speech discrimination (SD). Serviceable hearing was defined as PTA less than 50 dB and SD greater than 50%.

Results
The median cochlear maximum and mean doses were 6.9 Gy (range 1.6–16 Gy) and 2.7 Gy (range 0.7–5.0 Gy), respectively. With a median audiological follow-up of 35 months (range 6–58 months), the 1-, 2-, and 3-year actuarial rates of maintaining serviceable hearing were 93%, 77%, and 74%, respectively. No patient who received a mean cochlear dose less than 2 Gy experienced serviceable hearing loss (p = 0.035). Patients who received a mean cochlear dose less than 3 Gy had a 2-year hearing preservation rate of 91% compared with 59% in those who received a mean cochlear dose of 3 Gy or greater (p = 0.029). Those who had more than 25% of their cochlea receiving 3 Gy or greater had a higher rate of hearing loss (p = 0.030). There was no statistically significant correlation between serviceable hearing loss and age, tumor size, pre-GKS PTA, pre-GKS SD, pre-GKS Gardner-Robertson class, maximum cochlear dose, or the percentage of cochlear volume receiving 5 Gy. On multivariate analysis there was a trend toward significance for serviceable hearing loss with a mean cochlear dose of 3 Gy or greater (p = 0.074). Local control was 100% at 24 months. No patient developed facial or trigeminal nerve dysfunction.

Conclusions
With a median mean cochlear dose of 2.7 Gy, the majority of patients with serviceable hearing retained serviceable hearing 3 years after GKS. A mean cochlear dose less than 3 Gy was associated with higher serviceable hearing preservation.
Addressing the siphoning effect in new shunt designs by decoupling the activation pressure and the pressure gradient across the valve
Authors: Mattei Tobias A. , Morris Martin , Nowak Kathleen , Smith Daniel , Yee Jeremy , Goulart Carlos R. , Zborowski Anne , Lin Julian J. 
Published: December 2012

Object
Although several improvements have been observed in the past few years in shunt technology, currently available systems still present several associated problems. Among these, overdrainage along with its complications remains one of the great challenges for new shunt designs. To address the so-called siphoning effect, the authors provide a practical example of how it is possible to decouple the activation pressure and the pressure gradient across the valve through a 3–key component system. In this new shunt design, the flow is expected to depend only on the intracranial pressure and not on the pressure gradient across the valve, thus avoiding the so-called siphoning effect.

Methods
The authors used computer models to theoretically evaluate the mechanical variables involved in the operation of the newly designed valve, such as the fluid's Reynolds number, proximal pressure, distal pressure, pressure gradient, actual flow rate, and expected flow rate. After fabrication of the first superscaled model, the authors performed benchmark tests to analyze the performance of the new shunt prototype, and the obtained data were compared with the results predicted by the previous mathematical models.

Results
The final design of the new paddle wheel valve with the 3–key component antisiphoning system was tested in the hydrodynamics laboratory to prove that the siphoning effect did not occur. According to the calculations obtained using the LabVIEW program during the experiments, each time the distal pressure decreased without an increase in the proximal pressure (despite the range of the pressure gradient), the pin blocked the spinning of the paddle wheels, and the calculated fluid velocity through the system tended to zero. Such a situation was significantly different from the expected flow rate for such a pressure gradient in a siphoning situation without the new antisiphon system.

Conclusions
The design of this new prototype with a 3–key component antisiphoning system demonstrated that it is possible to decouple the activation pressure and the pressure gradient across the valve, avoiding the siphoning effect. Although further developments are necessary to provide a model compatible to clinical use, the authors believe that this new prototype illustrates the possibility of successfully addressing the siphoning effect by using a simple 3–key component system that is able to decouple the activation pressure and the pressure gradient across the valve by using a separate pressure chamber. It is expected that such proof of concept may significantly contribute to future shunt designs attempting to address the problem of overdrainage due to the siphoning effect.
Timing and mechanism of ischemic stroke due to extracranial blunt traumatic cerebrovascular injury
Authors: Griessenauer Christoph J. , Fleming J. Brett , Richards Boyd F. , Cava Luis P. , Curé Joel K. , Younan Duraid S. , Zhao Limin , Alexandrov Andrei V. , Barlinn Kristian , Taylor Tracy , Harrigan Mark R. 
Published: December 2012

Object
Extracranial cerebrovascular injury is believed to be an important cause of neurological injury in patients who have suffered blunt trauma. The authors sought to determine the timing and mechanisms of ischemic stroke in patients who suffered traumatic cerebrovascular injury (TCVI).

Methods
This is a prospective study of all patients with TCVI who were admitted to a Level I trauma center during a 28-month period. All patients who suffered blunt trauma and had risk factors for TCVI underwent screening CT angiography (CTA) of the head and neck on admission. All patients with either an ischemic stroke or CTA suggesting TCVI underwent confirmatory digital subtraction angiography (DSA). Patients with DSA-confirmed TCVI were treated with 325 mg aspirin daily; all patients were observed during their hospitalization for the occurrence of new ischemic stroke. In addition, a subset of patients with TCVI underwent transcranial Doppler ultrasonography monitoring for microembolic signals.

Results
A total of 112 patients had CTA findings suggestive of TCVI; 68 cases were confirmed by DSA. Overall, 7 patients had an ischemic stroke in the territory of the affected artery prior to or during admission. Four of the patients had their event prior to diagnosis with CTA and 2 occurred prior to DSA. In 1 patient the ischemic stroke was found to be due to an extracranial atherosclerotic carotid plaque, and this patient was excluded from further analysis. All patients with ischemic stroke had brain CT findings consistent with an embolic mechanism. Two (8.7%) of 23 monitored patients with TCVI had microembolic signals on transcranial Doppler ultrasonography.

Conclusions
Most ischemic strokes due to TCVI are embolic in nature and occur prior to screening CTA and initiation of treatment with aspirin.
The Y-shaped double-barrel bypass in the treatment of large and giant anterior communicating artery aneurysms
Authors: Dengler Julius , Kato Naoki , Vajkoczy Peter 
Published: December 2012

Large and giant anterior communicating artery (ACoA) aneurysms usually show partial thrombosis and incorporate both the A1 and A2 segments and crucial perforating vessels. Therefore, direct clip placement or endovascular strategies often fail, leaving cerebral bypass surgery as a relevant therapeutic option. The authors present 3 cases in which a giant or large ACoA aneurysm was successfully occluded using a new technique that applies a double-barrel radial artery bypass. A radial artery graft is modified into a Y-shaped double-barrel conduit. After both pterional and parasagittal craniotomies are carried out, the graft is tunneled between both sites and anastomosed in an end-to-side fashion proximally to either a superficial temporal artery (STA) or M2 branch and distally to bilateral A3 branches. Aneurysm occlusion is then conducted through the pterional or parasagittal craniotomy. In one case, a 42-year-old patient in whom an endovascular approach had failed, the authors performed an STA-A3-A3 bypass and proximal aneurysm occlusion. In two others, a 49-year-old man in whom coiling had failed and a 56-year-old man in whom a giant ACoA aneurysm was partially thrombosed, the authors performed an M2-A3-A3 double-barrel bypass followed by either proximal or distal aneurysm occlusion. Complete aneurysm occlusion with excellent bypass perfusion was documented in the first two cases. In the third case, the authors observed good bypass perfusion with persistent antegrade aneurysm filling, and thus endovascular coil embolization was added to completely occlude the aneurysm.
The Y-shaped double-barrel bypass using a radial artery graft allows for safe and effective occlusion of large and giant ACoA aneurysms that cannot be treated by direct clip application.
A 72-Week Randomized Study of the Safety and Efficacy of a Stavudine to Zidovudine Switch at 24 Weeks Compared to Zidovudine or Tenofovir Disoproxil Fumarate when Given with Lamivudine and Nevirapine
Authors: Phanuphak Nittaya , Ananworanich Jintanat , Teeratakulpisarn Nipat , Jadwattanakul Tanate , Kerr Stephen J , Chomchey Nitiya , Hongchookiat Piranun , Mathajittiphun Pornpen , Pinyakorn Suteeraporn , Rungrojrat Patcharawee , Praihirunyakit Pairoa , Gerschenson Mariana , Phanuphak Praphan , Valcour Victor , Kim Jerome H , Shikuma Cecilia ,   the SEARCH 003 Study Group
Published: December 2012

Background Due to superior long-term toxicity profiles, zidovudine (AZT) and tenofovir disoproxil fumarate (TDF) are preferred over stavudine (d4T) for first-line antiretroviral regimens. However, short-term d4T use could be beneficial in avoiding AZT-induced anaemia. Methods We randomized (1:1:1) 150 treatment-naive Thai HIV-infected adults with CD4+ T-cell count <350 cells/mm3 to arm 1 (24-week GPO-VIR S30® [d4T plus lamivudine (3TC) plus nevirapine (NVP)] followed by 48-week GPO-VIR Z250® [AZT plus 3TC plus NVP]), arm 2 (72-week GPO-VIR Z250®) or arm 3 (72-week TDF plus emtricitabine [FTC] plus NVP). Haemoglobin (Hb), dual energy x-ray absorptiometry, neuropathic signs, estimated glomerular filtration rate (eGFR), CD4+ T-cell count, plasma HIV RNA and adherence were assessed. Results In an intention-to-treat analysis, mean Hb decreased from baseline to week 24 in arm 2 compared with arm 1 (-0.19 versus 0.68 g/dl; P=0.001) and arm 3 (0.48 g/dl; P=0.010). Neuropathic signs were more common in arm 2 compared with arm 3 (20.4 versus 4.2%; P=0.028) at week 24. There were no differences in changes in peripheral fat and eGFR from baseline to weeks 24 and 72 among arms. CD4+ T-cell count increased more in arm 1 than arms 2 and 3 from baseline to week 24 (168 versus 117 and 118 cells/mm3; P=0.01 and 0.02, respectively) but the increase from baseline to week 72 was similar among arms. Conclusions A 24-week d4T lead-in therapy caused less anaemia and greater initial CD4+ T-cell count increase than initiating treatment with AZT. This strategy could be considered in patients with baseline anaemia or low CD4+ T-cell count. If confirmed in a larger study, this may guide global recommendations on antiretroviral initiation where AZT is more commonly used than TDF.
Producteur laitier en Afrique de l'Ouest : une modernité rêvée par les techniciens à l'épreuve du terrain
Authors: Corniaux Christian , Alary Véronique , Gautier Denis , Duteurtre Guillaume 
Published: December 2012

Résumé À l’instar des modèles de développement agricole en Occident, existe-t-il en Afrique de l’Ouest des producteurs laitiers « modernes » capables, selon la réthorique modernisante, d’affronter la concurrence du lait en poudre importé ? Pour répondre à cette question, il est nécessaire de savoir qui sont les producteurs laitiers ouest-africains. Notre analyse, basée sur trois typologies réalisées en périphérie des villes au Sénégal, en Mauritanie et au Mali, montre une grande diversité de situations. Néanmoins, la stratégie dominante est une stratégie sécuritaire, dans le cadre d’exploitations familiales relativement pauvres qui privilégient la production de céréales ou d’animaux sur pieds. Le lait n’est pas une priorité économique dans le système actuel de production. La figure du producteur laitier à l’occidentale n’existe pas encore en Afrique de l’Ouest.
Les petits producteurs dans le nouveau modèle agro-exportateur péruvien : entre subordination et stratégies propres
Authors: Marshall Anaïs , Mesclier Évelyne , Chaléard Jean-Louis 
Published: December 2012

Résumé Au Pérou, la politique d’ouverture des marchés économique et foncier, initiée par le gouvernement d’A. Fujimori en 1990, a provoqué de nombreux changements sur le piémont côtier péruvien, avec l’implantation d’entreprises agro-industrielles tournées vers l’exportation. L’analyse de l’évolution dans trois oasis (Motupe, Virú et Ica) montre que les petits producteurs sont confrontés à une double réalité : d’une part, une nouvelle concurrence sur les ressources foncières et hydriques et, d’autre part, la possibilité de tisser des liens avec les entreprises présentes sur le territoire local afin de produire pour de nouveaux marchés. Dans ce contexte, certains petits producteurs s’insèrent par eux-mêmes dans les nouvelles filières, tandis que d’autres sont incités à le faire par ces entreprises. Pratiquement tous continuent par ailleurs à diversifier leurs cultures, pour assurer la reproduction de leur famille comme pour approvisionner les marchés urbains nationaux. La comparaison de cas dans des situations géographiques différentes permet de conclure que les petits agriculteurs peuvent participer au développement d’un modèle agro-exportateur mis en place récemment et reposant sur des techniques exogènes sans renoncer à avoir des stratégies propres.
Transferts publics et adaptations des ménages agricoles au processus de libéralisation au Sud du Mexique
Authors: Léonard Éric , Palma Rafael , Brun Virginie 
Published: December 2012

Résumé Depuis le milieu des années 1990, le Mexique est engagé dans un processus d’insertion compétitive qui met en question le devenir des petites exploitations familiales composant la trame de son secteur agricole. Sur la base d’une enquête réalisée auprès de 320 ménages ruraux, cet article explore les formes de reconfiguration des organisations économiques familiales à partir d’une analyse de leurs revenus. Il en examine la structure et la distribution en référence à l’hypothèse d’évolution trimodale des formes d’insertion dans les marchés proposée par le Rapport sur le développement dans le monde 2008 de la Banque mondiale : la spécialisation agricole via l’insertion dans les chaînes de valeur agro-industrielles ; la diversification des activités rurales agricoles et non agricoles ; et la sortie de l’agriculture par la migration. L’article s’attache au rôle des programmes publics d’appui aux ménages ruraux dans la réorganisation des structures d’activité, ainsi que dans les dynamiques de différenciation socio-spatiale associées au processus d’insertion compétitive.
Adaptation des sociétés bédouines de la côte nord-ouest de l'Égypte au changement global
Authors: Alary Véronique , Daoud Ibrahim , Abdelzaher Mona , Salama Omar , Aboul-Naga Adel , Merveille Nicolas , Tourrand Jean-François , Dury Sandrine 
Published: December 2012

Résumé En ce début de millénaire, avec une croissance démographique de 1,9 % par an empiétant sur le rural (environ 250 000 ha urbanisés en vingt ans) et à peine 3,5 % de son territoire cultivable, l’Égypte fait face à d’importants défis. Les zones arides (8 % du pays), bien que menacées par les changements climatiques actuels, présentent un réel potentiel agricole. Le projet de recherche ELVULMED propose une analyse des processus d’adaptation des sociétés bédouines de la Côte Nord-Ouest suite à quinze ans de sécheresse, de 1995 à 2011. Les premiers résultats montrent des changements sociétaux profonds et de nouvelles formes d’adaptation liées à l’urbanisation croissante de la côte, formes dépassant le système traditionnel bédouin basé sur l’élevage.