bluuebunny/crossref_metadata_2025 huggingface dataset:
The importance of the cortical subarachnoid space in understanding hydrocephalus
Authors: Rekate Harold L. , Nadkarni Trimurti D. , Wallace Donna
Published: June 2008

Object

In this paper the authors define the role of the cortical subarachnoid space (CSAS) in poorly understood forms of hydrocephalus to cerebrospinal fluid (CSF) dynamics to improve understanding of the importance of the CSAS and its role in selecting patients for endoscopic third ventriculostomy (ETV). The secondary purpose of this work was to define testable hypotheses to explain enigmatic disorders of CSF dynamics and to suggest how these concepts could be tested.

Methods

The magnitude of the contribution of the CSAS is explored using the solid geometry of concentric spheres. With this starting point, clinical conditions in which CSF dynamics are not easily understood are explored regarding the potential role of the CSAS. Overall, problems of CSF dynamics are easily understood. Insights may be gained when the results of a pathological process or its treatment vary from what has been expected.

Results

Acute changes in ventricular volume at the time that hydrocephalus develops, the failure of shunts, and the changes in ventricular volume with shunt repair may occur very rapidly. Changes in the volume of water in the brain, especially in the brain substance itself, are unlikely to occur at this rapid rate and may be interpreted as a simple redistribution of the CSF between the ventricle and CSAS with no initial change in the actual volume of brain parenchyma. Problems such as pseudotumor cerebri, shunt failure with nonresponsive ventricles, and negative-pressure hydrocephalus can be explained by assessing the ability of ventricular CSF to flow to the CSAS and the ability of this fluid to exit this compartment. Ventricular enlargement at the time of shunt failure implies a failure of flow between the ventricles and CSAS, implying that all patients who show this phenomenon are potential candidates for ETV.

Conclusions

The important role of the CSAS in the pathophysiology of various forms of hydrocephalus has been largely ignored. Attention to the dynamics of the CSF in this compartment will improve understanding of enigmatic conditions of hydrocephalus and improve selection criteria for treatment paradigms such as ETV. These concepts lead to clearly defined problems that may be solved by the creation of a central database to address these issues.
Management of hydrocephalus in infants by using shunts with adjustable valves
Authors: Weinzierl Martin R. , Rohde Veit , Gilsbach Joachim M. , Korinth Marcus
Published: June 2008

Object

Previous reports suggest that the use of adjustable differential-pressure valves may improve shunt performance. The absence of a flow- or siphon-controlled mechanism, however, is a concern. The goal of this prospective study was to assess the efficacy of valve adjustments in preventing slitlike ventricles in children < 6 months old after the first shunt insertion.

Methods

A total of 15 infants < 6 months of age who were undergoing initial shunt placement were included. Imaging was performed preoperatively, at 14 days postoperatively, and every 4 weeks thereafter. Ventricle size was assessed using ultrasonography and MR imaging or cerebral CT scanning at 1 and 2 years postoperatively. Clinical follow-up duration was 24 months for all patients. Valve settings were changed by 50 mm H2O if ventricle size decreased by 30% compared to preoperative size.

Results

The valve pressure setting was increased to 200 mm H2O in 11 children within the follow-up time, whereas ventricle size decreased from 0.6 ± 0.08 to 0.39 ± 0.09 (frontal/occipital horn ratio, mean ± standard deviation). There was neither clinical nor radiological evidence of underdrainage.

Conclusions

The adjustable differential-pressure valve used in this study was not effective in preventing slitlike ventricles in the majority of patients. Despite the small number of patients, this study provides a rationale for examining whether new shunt designs (gravitational shunt valves) are superior to conventional shunt systems in managing challenging hydrocephalus problems.
Effect of preoperative skull block on pediatric moyamoya disease
Authors: Ahn Hyun Joo , Kim Jie Ae , Lee Jeong Jin , Kim Han Soo , Shin Hyung Jin , Chung Ik Soo , Kim Jin Kyoung , Gwak Mi Sook , Choi Soo Joo
Published: June 2008

Object

Stable hemodynamics, normocapnia, and adequate pain relief are considered important factors in the reduction of neurological complications in pediatric patients undergoing encephaloduroarteriomyosynangiosis (EDAMS) operations for the treatment of moyamoya disease. A preoperative skull block may reduce hemodynamic fluctuations and hypo- or hyperventilation due to emergence delirium or oversedation and provide adequate pain relief, thereby reducing postoperative morbidity.

Methods

Pediatric patients (age 3–13 years) undergoing EDAMS surgery for moyamoya disease were randomly divided into a nerve block (NB) group (18 cases) or control group (21 cases). The treatment group patients received a preoperative NB (0.25% 5–8 ml bupivacaine mixed with 20–40 mg methylprednisolone) targeting the supraorbital, supratrochlear, auriculotemporal, and posterior auricular nerves. Patients in the control group did not receive NB. General anesthesia with sevoflurane was induced in both groups.

Results

In the NB group, stable hemodynamic parameters were obtained with a lower sevoflurane concentration than in the control group. For delirious awakening, the odds ratio in the control group was 4.9 compared with the NB group. Pain and analgesic requirement were higher in the control patients than in the NB-treated patients during the postanesthesia care unit stay. However, the arterial CO2 tension in the postanesthesia care unit did not differ between the 2 groups. The odds ratio in the control group for the rate of morbidity (cerebral infarction and reversible ischemic neurological deficits) during the first 24 hours following the operation was 3.2 compared with the NB group.

Conclusions

The use of skull block during EDAMS surgery provided easy hemodynamic control, calm awakening, and better pain relief and may be related to the reduced postoperative morbidity.
Extraventricular neurocytoma in neurofibromatosis Type 1
Authors: Raja Ali I. , Yeaney Gabrielle A. , Jakacki Regina I. , Hamilton Ronald L. , Pollack Ian F.
Published: June 2008

Neurocytomas are rare tumors of the central nervous system that are typically located in the ventricular system. The authors report a case of a child with neurofibromatosis Type 1 (NF1) who had a tumor of the optic nerves and chiasm with signal abnormality extending through the diencephalon, as well as an occipital lobe mass, which was presumed to be part of the visual pathway neoplasm. Because the occipital lobe lesion slowly increased in size over time, while the other areas remained stable, a biopsy was performed. Pathological evaluation revealed an extraventricular neurocytoma of extraventricular neurocytoma. To the authors' knowledge, neurocytomas have not been previously reported in patients with NF1. Because visual pathway gliomas are extremely common in children with NF1, they are often treated empirically as low-grade gliomas without histological confirmation. The importance of obtaining a biopsy in lesions that have atypical imaging features is highlighted.
Retrieval of ventricular catheter with the aid of endoscopy
Authors: Pettorini Benedetta Ludovica , Frassanito Paolo , Tamburrini Gianpiero , Massimi Luca , Caldarelli Massimo , Di Rocco Concezio
Published: June 2008

Multilocular hydrocephalus usually requires placement of multiple ventricular catheters for the treatment of secondary cysts and intraventricular septation. The formation of strong adhesions can embed the catheters so that they cannot be removed without a higher risk of intraventricular hemorrhage. Moreover, the devices could represent a nidus for infection and a risk for formation and enlargement of intraventricular secondary cysts. Neuroendoscopy allows the surgeon safely to reach the ventricular catheters that have been left or lost in the ventricular cavity, and to remove them via a minimally invasive approach. In this paper, the authors document another application of ventricular endoscopy in the management of this kind of hydrocephalus. The removal of an unnecessary and no longer useful prosthetic device that is a possible focus of infection justifies endoscopic treatment, which, in this experience, is not associated with morbidity.
Craniocervical junction fusions in patients with hindbrain herniation and syringohydromyelia
Authors: Fenoy Albert J. , Menezes Arnold H. , Fenoy Kathleen A.
Published: June 2008

Object

Patients with hindbrain herniation or the so-called Chiari malformation Type I (CM-I) and/or syringohydromyelia are treated with dorsal decompression alone; however, a small percentage of patients with other associated abnormalities require concomitant dorsal craniocervical junction (CCJ) fusion. The authors surveyed the indications for CCJ fusions in this population.

Methods

A retrospective review of University of Iowa medical records and radiographs obtained between 1996 and 2005 was performed. Inclusion criteria encompassed patients with diagnoses of CM-I and/or syringohydromyelia requiring dorsal CCJ fusions, and others with CCJ abnormalities who had CM-I and/or syringohydromyelia.

Results

Two hundred thirty-four patients were identified, all of whom were symptomatic at presentation. Their ages ranged from 2.5 to 86 years; 33% of the patients were < 16 years of age. Patients were categorized as follows, with some being assigned to > 1 category: Group I, congenital or acquired CCJ abnormalities with reducible bone compression (25% of patients); Group II, previous anterior CCJ/upper brainstem decompression (44%); Group III, occipitocervical complex instability with CM-I and/or syringohydromyelia but without CCJ bone abnormalities requiring adjunctive posterior fossa decompression (26%); and Group IV, musculoligamentous instability, either from pathological states or from muscle dehiscence from repeated posterior fossa procedures (14%). Instrumentation was used in 96% of patients, with all 96% receiving semirigid fixation with titanium loop and sublaminar cables; all fusion constructs incorporated autologous bone. At last follow-up evaluation, fusion was radiographically complete in 97%, and symptom improvement was seen in 92%.

Conclusions

Dorsal CCJ fusions are required in patients with CM-I and/or syringohydromyelia who have concomitant CCJ abnormalities (Groups I and II). A definite group (CM-I and/or syringohydromyelia) without bone abnormality exists (Groups III and IV). This may be due to muscle weakness secondary to a high syrinx.
Impact of preoperative neurological status on perioperative morbidity associated with anterior and posterior cervical fusion
Authors: Shamji Mohammed F. , Cook Chad , Tackett Sean , Brown Christopher , Isaacs Robert E.
Published: June 2008

Object

Cervical spine fusion is performed for various indications in patient populations ranging from young and healthy to aged and frail. Whereas disease pathoanatomy dictates the surgical approach, preoperative neurological status does not necessarily implicate a specific technique. Although one expects anterior decompression to be performed over fewer segments in healthier patients who experience fewer complications and faster recovery, the impact of pre-operative myelopathy on perioperative complications remains unclear. No large-scale study has evaluated rates of common complications for cervical fusion or their association with surgical approach and neurological status.

Methods

Data for 96,773 patients who underwent cervical fusion for degenerative disease between 1988 and 2003 were collected from the Nationwide Inpatient Sample database. Patients were grouped according to surgical approach (anterior versus posterior) and preoperative neurological status (myelopathic versus nonmyelopathic). Multivariate regression was used to evaluate group effects on selected postoperative complications, length of stay, and disposition at the time of hospital discharge. Although this technique can control for the observed covariates, the absence of key information such as the number of fused levels precludes statistical comparison between patients who underwent anterior or posterior approaches.

Results

In this study the authors confirmed that preoperative neurological status impacts perioperative morbidity. For example, patients who were nonmyelopathic and underwent an anterior approach were 7 years younger than the rest of the cohort, and they had a mortality rate of 0.05%. Transfusion was required in 0.34%, and venous thromboembolism occurred in 0.04%. Conversely, these rates were > 13-fold higher in patients with myelopathy who underwent a posterior approach. Furthermore, independent of approach, preoperative myelopathy is highly prognostic of death, pneumonia, transfusion, infection, length of stay, and posthospital disposition. These outcomes at least doubled, with some increasing > 10-fold.

Conclusions

This nationwide study clarifies the frequency and associations of inpatient complications encountered when treating cervical spine disease. Whereas immediate complications due to anterior approaches are limited, patients with myelopathy who undergo a posterior approach have a more sobering outlook. This study shows that clinical myelopathy augments rates of complication during cervical fusion, regardless of the approach. The exclusion of pathoanatomical data from the Nationwide Inpatient Sample database, of key importance in guiding the surgical approach, prevents any conclusions being drawn about the merits and disadvantages of anterior versus posterior surgery.
Rheumatoid arthritis as a risk factor for a narrow C-2 pedicle: 3D analysis of the C-2 pedicle screw trajectory
Authors: Miyata Masahiko , Neo Masashi , Ito Hiromu , Yoshida Makoto , Fujibayashi Shunsuke , Nakamura Takashi
Published: June 2008

Object

Vertebral artery (VA) injury is a potentially serious complication of C-2 pedicle screw (PS) fixation. Although this surgery is frequently performed in patients with rheumatoid arthritis (RA), few studies have compared the risk of VA injury in patients with and without RA. In this study, the authors compare the morphological risk of VA injury relating to C-2 PS fixation in patients with and without RA.

Methods

A total of 110 3D CT images of the cervical spine including the axis were evaluated. Fifty patients with RA and 60 patients without RA were included in the study. The maximum PS diameter (MPSD) that could be used at C-2 without breaching the cortex was measured in 3D using a computer-assisted navigation system. A narrow-pedicle carrier was defined as a patient with an MPSD of 4 mm or less.

Results

In the RA group, 42 of 100 MPSDs were ≤ 4 mm, and 30 of 50 patients (60%) were narrow-pedicle carriers. In the non-RA group, 10 of 120 MPSDs (8%) were ≤ 4 mm, and 8 of 60 (13%) patients were narrow-pedicle carriers. The MPSD, the anteroposterior (AP) diameter of C-3, and the ratio of MPSD to the AP diameter of C-3 were significantly smaller in the RA group than in the non-RA group. Multiple logistic regression analysis showed that RA and narrow C-3 AP diameter were significant risk factors for a narrow-pedicle carrier.

Conclusions

Rheumatoid arthritis is a significant risk factor for a narrow C-2 pedicle. When performing PS placement at C-2, particularly in patients with RA, thorough preoperative evaluation of the bone architecture is very important for avoiding inadvertent injury to the VA.
Microsurgical management of spinal schwannomas: evaluation of 128 cases
Authors: Safavi-Abbasi Sam , Senoglu Mehmet , Theodore Nicholas , Workman Ryan K. , Gharabaghi Alireza , Feiz-Erfan Iman , Spetzler Robert F. , Sonntag Volker K. H.
Published: June 2008

Object

The authors conducted a study to evaluate the clinical characteristics and surgical outcomes in patients with spinal schwannomas and without neurofibromatosis (NF).

Methods

The data obtained in 128 patients who underwent resection of spinal schwannomas were analyzed. All cases with neurofibromas and those with a known diagnosis of NF Type 1 or 2 were excluded. Karnofsky Performance Scale (KPS) scores were used to compare patient outcomes when examining the anatomical location and spinal level of the tumor. The neurological outcome was further assessed using the Medical Research Council (MRC) muscle testing scale.

Results

Altogether, 131 schwannomas were treated in 128 patients (76 males and 52 females; mean age 47.7 years). The peak prevalence is seen between the 3rd and 6th decades. Pain was the most common presenting symptom. Gross-total resection was achieved in 127 (97.0%) of the 131 lesions. The nerve root had to be sacrificed in 34 cases and resulted in minor sensory deficits in 16 patients (12.5%) and slight motor weakness (MRC Grade 3/5) in 3 (2.3%). The KPS scores and MRC grades were significantly higher at the time of last follow-up in all patient groups (p = 0.001 and p = 0.005, respectively).

Conclusions

Spinal schwannomas may occur at any level of the spinal axis and are most commonly intradural. The most frequent clinical presentation is pain. Most spinal schwannomas in non-NF cases can be resected totally without or with minor postoperative deficits. Preoperative autonomic dysfunction does not improve significantly after surgical management.
Surgical treatment for intramedullary spinal cord melanocytomas
Authors: Horn Eric M. , Nakaji Peter , Coons Stephen W. , Dickman Curtis A.
Published: June 2008

Spinal meningeal melanocytomas are rare lesions that are histologically benign and can behave aggressively, with local infiltration. The authors present their experience with intramedullary spinal cord melanocytomas consisting of 3 cases, which represents the second largest series in the literature. A retrospective chart review was performed following identification of all spinal melanocytomas treated at the author's institution, based on information obtained from a neuropathology database. The charts were reviewed for patient demographics, surgical procedure, clinical outcome, and long-term tumor progression. Three patients were identified in whom spinal melanocytoma had been diagnosed between 1989 and 2006. The patients' ages were 37, 37, and 48 years, and the location of their tumor was C1–3, T9–10, and T-12, respectively. All 3 had complete resection with no adjuvant radiotherapy during follow-up periods of 16, 38, and 185 months, respectively. One patient demonstrated a recurrence 29 months after resection and the other 2 patients have demonstrated asymptomatic recurrences on imaging studies obtained at 16 and 38 months following resection.

With these cases added to the available literature, the evidence strongly suggests that complete resection is the treatment of choice for spinal melanocytomas. Even with complete resection, recurrences are common and close follow-up is needed for the long term in these patients. Radiation therapy should be reserved for those cases in which complete resection is not possible or in which there is recurrence.
Extranodal Rosai–Dorfman disease with multilevel lumbar spinal lesions
Authors: Ma Junming , Xiao Jianru , Wang Liangzhe
Published: June 2008

The authors describe the case of a 44-year-old man with multilevel lumbar spinal Rosai–Dorfman disease (RDD), a rare clinical entity. To the authors' knowledge, there have been only 2 cases of lumbar spinal involvement of RDD (epidural) reported in the literature, and the current case is the third but the only one showing lumbar spinal intradural involvement of RDD. This case of RDD mimicked a meningioma both clinically and radiologically. The patient underwent a procedure in which the tumor was excised, and postoperatively the patient made a clinically acceptable recovery. Vertebral canal involvement of RDD should be considered in the differential diagnosis of vertebral canal tumors. Resection is an acceptable treatment option.
Posterior midline approach for single-stage en bloc resection and circumferential spinal stabilization for locally advanced Pancoast tumors
Authors: Jain Surbhi , Sommers Eric , Setzer Matthias , Vrionis Frank
Published: June 2008

The treatment of Pancoast (superior sulcus) tumors that extensively invade the vertebral column remains controversial. Different surgical approaches involving multistage resection techniques have been previously described for superior sulcus tumors that invade the chest wall and spinal column. Typically a posterior approach to stabilize the spine is followed by a second-stage thoracotomy (posterolateral or trap door) for definitive en bloc resection of stage T4 Pancoast tumors. The authors report and elaborate on a surgical technique successfully used for an en bloc resection as well as spinal stabilization through a single-stage posterior approach without any added morbidity.

Two patients with histologically proven Pancoast tumors were treated by single-stage resection and stabilization through a posterior approach at the H. Lee Moffitt Cancer Center. A wedge lung resection or lobectomy was performed by the chest surgeon utilizing the chest wall defect. Placement of an anterior cage (in one case) and posterior cervicothoracic spinal instrumentation (in both cases) was performed during the same operation. Average blood loss was 675 ml and surgical time was 7 hours. The median hospital stay was 9 days (range 7–11 days). Both patients did well postoperatively and were free of recurrence at the 2-year follow-up.

Radical resection of Pancoast tumors including lobectomy, chest wall resection, costotransversectomy, and partial or complete vertebrectomy with simultaneous instrumentation for spinal stabilization can be performed through a posterior single-stage approach.
Autograft versus allograft with or without demineralized bone matrix in posterolateral lumbar fusion in rabbits
Authors: Urrutia Julio , Thumm Nicolas , Apablaza Daniel , Pizarro Felipe , Zylberberg Alejandro , Quezada Felipe
Published: June 2008

Object

Posterolateral spinal fusions are performed to treat different spinal disorders. Autograft continues to be the gold standard; it is, however, associated with donor site morbidity and limited sources. Allograft has been used, but has been reported to result in lower fusion rates. Demineralized bone matrix (DBM) has also been used and reportedly increases the fusion rate in a variety of critical defect models. Different forms of DBM are available, not all have been independently studied. To evaluate the effect of a xenogenic DBM added to allograft on the fusion rate of posterolateral lumbar spine arthrodesis the authors designed an experimental study comparing posterolateral fusion rate using autograft, allograft, and allograft plus a xenogenic DBM in a validated animal model.

Methods

A bilateral, 1-level (L4–5) intertransverse process fusion was performed in 45 male New Zealand rabbits. Iliac crest bone graft was harvested bilaterally from each rabbit. The rabbits were randomly assigned to 3 groups: Group I, Autograft, 15 rabbits; Group II, Allograft, 15 rabbits; and Group III, Allograft plus DBM in a paste form (Dynagraft). The animals were killed 8 weeks after surgery. Fusion was assessed radiographically and by manual palpation by 2 independent observers. The results were analyzed using the Fisher exact test and chi-square test.

Results

The fusion rate was 46.6% (7 of 15 rabbits) in the autograft group, 33.3% (5 of 15 rabbits) in the allograft group, and 33.3% (5 of 15 rabbits) in the allograft plus DBM group (p > 0.05).

Conclusions

Autograft produced a higher fusion rate than allograft in this spinal fusion rabbit model, but the difference was not statistically significant. Allograft plus xenogenic DBM showed the same fusion rate as allograft alone.
Influence of thread design on pedicle screw fixation
Authors: Krenn Michael Hannes , Piotrowski Wolfgang Peter , Penzkofer Rainer , Augat Peter
Published: June 2008

Object

The authors conducted a study to determine the thread properties that provide optimal screw fixation in cancellous bone, when screws of the same external screw diameter are used.

Methods

Three compliance engineering–certified screws in clinical use, all of the same external diameter and length, were compared in an axial pullout experiment with respect to advantageous thread properties. As test material, standardized Sawbone blocks with 3 different densities (0.12, 0.16, and 0.32 g/cm3) were used.

Results

Screw thread Type 1, whose flank overlap area (FOA; 261 mm2) results from narrowing the conical core in the thread area, showed significantly better holding strength than the other types. Screw thread Type 2 (FOA 326 mm2) with a conical but thicker core and a smaller thread pitch was found to be the only one without increase of pull-out forces when test materials density changed from 0.12 to 0.16 g/cm3. A screw tested as control, with a constant (cylindrical) core diameter (Type 3; FOA 206 mm2), had the same thread pitch as Type 1 but without the compressive effect on the surrounding bur hole wall material. Nevertheless, it showed higher pullout forces in the 0.16-g/cm3material than screw Type 2.

Conclusions

By reducing the core diameter of a screw toward the tip, while maintaining a constant nominal (external) diameter, one achieves frictional connection due to compression of surrounding material. In addition, the FOA is increased, which, in summary, leads to better fixation, as shown by screw Type 1.
Bündelung als Strategie in der Luzerner Waldpolitik | Bundling as a strategy within the forest policy for Lucerne
Authors: Schmidhauser Albin
Published: June 2008

From weakness to strength: the small-structured ownerships in the Lucerne forests complicate a future- and competitive-directed forest management. The cantonal forest policy analyzed the weaknesses of the system and created the basic framework requirements for a bundling of forest management and the timber industry. Due to the three projects Regional Organization (Regionale Organisation), Forest Wood (Waldholz) and Surplus Wood (Mehrwert Holz), restrictions are being eased on timber supply, placement and commercialization, which allows more flexible and competitive structures. As a result, the larger-scale management leads to lower production costs at the interface between the forest and timber industries, as well as for the promotion of wood.
Waldbiodiversität im Kanton Luzern | Forest biodiversity in the canton Lucerne
Authors: Frey Ueli
Published: June 2008

The promotion of forest biodiversity in Lucerne is conducted by the office of Landwirtschaft und Wald (Lawa). The biodiversity program 2008–2011 is coordinated with the program agreement “Biodiversität im Wald” between the federal and the cantonal authorities. The canton Lucerne has well-developed planning criteria available which allow a correct prioritization during the promotion and a goal oriented investment of the available financial resources. One difficulty with the application of the biodiversity program is the large portion of private forest owners in the canton Lucerne. The following measures which are eligible for grants and their application are discussed in more detail: old growth, forest edges, forest ponds and forest reserves.
Die Unesco-Biosphäre Entlebuch und ihre Nachhaltigkeitsstrategie | The Unesco Biosphere Entlebuch and its strategy of sustainability
Authors: Coch Thomas
Published: June 2008

The Unesco Biosphere Entlebuch (UBE) is situated in the southern part of the canton of Lucerne and covers the valley of “Kleine Emme”, parts of the Napf region and of the first alpine mountain chains. Officially certified by the Unesco Committee in autumn 2001, it is the first Swiss Biosphere Reserve following the Unesco Sevilla Criteria, published in 1995. As the UBE was, in worldwide context, also the first Biosphere Reserve based on a public election, participatory work is still the main driving action in its development. Main targets in the protection of ecosystems are peat lands – especially raised bogs, fens, karst biotopes and forest communities. Following national obligations from 2007, the UBE is converted now into a regional park of national importance (Regionaler Naturpark). This might produce conflicts in some cases, especially in the development zone or in connection with activities enhancing the economic sustainability.
Nachhaltiger Schutzwald entlang von Fliessgewässern | Sustainable protection forest along bodies of flowing water
Authors: Covi Silvio
Published: June 2008

As a result of the flooding in the summer of 2005, the canton Lucerne is paying more attention to the protection forests along bodies of flowing water. Within the mapping framework of protection forests, a new category entitled “channel protection forest” has been assessed. The project “sustainable protection forest along bodies of flowing water” (Nasef) recognizes the sections of forested channels which may pose a risk in terms of natural hazards for people as well as for significant material assets. It evaluates what actions are needed in a harmonized way and sets the priorities for the necessary actions. The basis for evaluation and translation are the guidelines “sustainability and measurement of results for protection forests” (NaiS), which have been further developed by taking into account the forest stands growing on the banks of brooks. The objectives of Nasef are the preventive management of the protection forest growing along bodies of flowing water and, in the long term, the stabilization of the brook banks. This raises the considerable challenge to coordinate sylvicultural measures in protection forests in combination with maintenance measures within the flooding area. The article describes the basic conditions, history of origin, project organization, translation and first experiences with Nasef.
Identification of Minor Secondary Metabolites from the Latex of Croton lechleri (Muell-Arg) and Evaluation of Their Antioxidant Activity
Authors: De Marino Simona , Gala Fulvio , Zollo Franco , Vitalini Sara , Fico Gelsomina , Visioli Francesco , Iorizzi Maria
Published: July 2008

Dragon’s blood (Sangre de drago), a viscous red sap derived from Croton lechleri Muell-Arg (Euphorbiaceae), is extensively used by indigenous cultures of the Amazonian basin for its wound healing properties. The aim of this study was to identify the minor secondary metabolites and test the antioxidant activity of this sustance. A bioguided fractionation of the n-hexane, chloroform, n-butanol, and aqueous extracts led to the isolation of 15 compounds: three megastigmanes, four flavan-3-ols, three phenylpropanoids, three lignans, a clerodane, and the alkaloid taspine. In addition to these known molecules, six compounds were isolated and identified for the first time in the latex: blumenol B, blumenol C, 4,5-dihydroblumenol A, erythro-guaiacyl-glyceryl-β-O-4’- dihydroconiferyl ether, 2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-propane-1,3-diol and floribundic acid glucoside. Combinations of spectroscopic methods (1H-, 13C- NMR and 2D-NMR experiments), ESI-MS, and literature comparisons were used for compound identification. In vitro antioxidant activities were assessed by DPPH, total antioxidant capacity and lipid peroxidation assays. Flavan-3-ols derivatives (as major phenolic compounds in the latex) exhibited the highest antioxidant activity.
Conversion of Oximes to Carbonyl Compounds by Triscetylpyridinium Tetrakis(oxodiperoxotungsto) Phosphate (PCWP)-mediated Oxidation with Hydrogen Peroxide
Authors: Ballistreri Francesco P. , Chiacchio Ugo , Rescifina Antonio , Tomaselli Gaetano , Toscano Rosa M.
Published: July 2008

Aromatic and aliphatic oximes have been deoximated in chloroform-water to the corresponding aldehydes with dilute hydrogen peroxide and triscetylpyridinium tetrakis (oxodiperoxotungsto) phosphate as catalyst. The presence of dipolarophiles in the reaction mixtures allows a competitive reaction that converts oximes into isoxazole and isoxazoline derivatives via the intermediate formation of nitrile oxide species.
Preparation of Chitosan from Brine Shrimp (Artemia urmiana) Cyst Shells and Effects of Different Chemical Processing Sequences on the Physicochemical and Functional Properties of the Product
Authors: Tajik Hossein , Moradi Mehran , Rohani Seyed Mehdi Razavi , Erfani Amir Mehdi , Jalali Farnood Shokouhi Sabet
Published: July 2008

Chitosan (CS) was prepared from Artemia urmiana cyst shells using the same chemical process as described for the other crustacean species, with minor adjustments in the treatment conditions. The influence of modifications of the CS production process on the physiochemical and functional properties of the CS obtained was examined. The study results indicate that Artemia urmiana cyst shells are a rich source of chitin as 29.3-34.5% of the shell’s dry weight consisted of this material. Compared to crab CS (selected as an example of CS from a different crustacean source) Artemia CS exhibited a medium molecular weight (4.5-5.7 ×105 Da), lower degree of deacetylation (67-74%) and lower viscosity (29-91 centiposes). The physicochemical characteristics (e.g., ash, nitrogen and molecular weight) and functional properties (e.g., water binding capacity and antibacterial activity) of the prepared Artemia CSs were enhanced, compared to control and commercial samples, by varying the processing step sequence.
Stable Spirocyclic Meisenheimer Complexes
Authors: Al-Kaysi Rabih O. , Gallardo Iluminada , Guirado Gonzalo
Published: July 2008

Meisenheimer complexes are important intermediates in Nucleophilic Aromatic Substitution Reactions (SNAr). They are formed by the addition of electron rich species to polynitro aromatic compounds or aromatic compounds with strong electron withdrawing groups. It is possible to distinguish two types of Meisenheimer or σ-complexes, the σHcomplex or σX-complex (also named ipso), depending on the aromatic ring position attacked by the nucleophile (a non-substituted or substituted one, respectively). Special examples of σX- or ipso-complexes are formed through intermediate spiro adducts, via intramolecular SNAr. Some of these spirocyclic Meisenheimer complexes, a type of σXcomplex, are exceptionally stable in solution and/or as solids. They can be isolated and characterized using X-ray, and various spectroscopic techniques such as NMR, UV-Vis, IR, and fluorescence. A few of these stable spirocyclic Meisenheimer complexes are zwitterionic and exhibit interesting photophysical and redox properties. We will review recent advances, synthesis and potential applications of these stable spirocyclic Meisenheimer complexes.
Efficient and Simple Synthesis of 6-Aryl-1,4-dimethyl-9H-carbazoles
Authors: Caruso Anna , Voisin-Chiret Anne Sophie , Lancelot Jean-Charles , Sinicropi Maria Stefania , Garofalo Antonio , Rault Sylvain
Published: July 2008

A synthetic method for the preparation of 6-aryl-1,4-dimethyl-9H-carbazoles involving a palladium catalyzed coupling reaction of 1,4-dimethyl-9H-carbazole-6-boronic acids and (hetero)aryl halides is described.
Pre-fractionated Microbial Samples – The Second Generation Natural Products Library at Wyeth
Authors: Wagenaar Melissa M.
Published: July 2008

From the beginning of the antibiotic era in the 1940s to the present, Wyeth has sustained an active research program in the area of natural products discovery. This program has continually evolved through the years in order to best align with the “current” drug discovery paradigm in the pharmaceutical industry. The introduction of highthroughput screening and the miniaturization of assays have created a need to optimize natural product samples to better suit these new technologies. Furthermore, natural product programs are faced with an ever shortening time period from hit detection to lead characterization. To address these issues, Wyeth has created a pre-fractionated natural products library using reversed-phase HPLC to complement their existing library of crude extracts. The details of the pre-fractionated library and a cost-benefit analysis will be presented in this review.
DNA Extraction Systematics for Spectroscopic Studies
Authors: Palma Bianca Fogazza , Ferrari Amanda Borges , Bitar Renata Andrade , Cardoso Maria Angélica Gargione , Martin Airton A. , Da Silva Martinho Herculano
Published: June 2008

Study of genetic material allows the comprehension the origin of the many biochemical changes that follow diseases, like cancer, promoting the development of early preventive inquiry and more efficient individual treatments. Raman spectroscopy can be an important tool in DNA study, since it allows probe molecular vibrations of genetic material in a fast way. The present work established a systematic way for extract DNA in suitable concentrations and structural integrity allowing studies by Raman spectroscopy or other spectroscopic technique, including bio-analytical sensors for probing genetic alterations.
Sensor for Measuring Strain in Textile
Authors: Mattmann Corinne , Clemens Frank , Tröster Gerhard
Published: June 2008

In this paper a stain sensor to measure large strain (80%) in textiles is presented. It consists of a mixture of 50wt-% thermoplastic elastomer (TPE) and 50wt-% carbon black particles and is fiber-shaped with a diameter of 0.315mm. The attachment of the sensor to the textile is realized using a silicone film. This sensor configuration was characterized using a strain tester and measuring the resistance (extension-retraction cycles): It showed a linear resistance response to strain, a small hysteresis, no ageing effects and a small dependance on the strain velocity. The total mean error caused by all these effects was +/-5.5% in strain. Washing several times in a conventional washing machine did not influence the sensor properties. The paper finishes by showing an example application where 21 strain sensors were integrated into a catsuit. With this garment, 27 upper body postures could be recognized with an accuracy of 97%.
A Spatial-Spectral Approach for Visualization of Vegetation Stress Resulting from Pipeline Leakage
Authors: Van derWerff Harald , Van der Meijde Mark , Jansma Fokke , Van der Meer Freek , Groothuis Gert Jan
Published: June 2008

Hydrocarbon leakage into the environment has large economic and environmental impact. Traditional methods for investigating seepages and their resulting pollution, such as drilling, are destructive, time consuming and expensive. Remote sensing is an efficient tool that offers a non-destructive investigation method. Optical remote sensing has been extensively tested for exploration of onshore hydrocarbon reservoirs and detection of hydrocarbons at the Earth’s surface. In this research, we investigate indirect manifestations of pipeline leakage by way of visualizing vegetation anomalies in airborne hyperspectral imagery. Agricultural land-use causes a heterogeneous landcover; variation in red edge position between fields was much larger than infield red edge position variation that could be related to hydrocarbon pollution. A moving and growing kernel procedure was developed to normalzie red edge values relative to values of neighbouring pixels to enhance pollution related anomalies in the image. Comparison of the spatial distribution of anomalies with geochemical data obtained by drilling showed that 8 out of 10 polluted sites were predicted correctly while 2 out of 30 sites that were predicted clean were actually polluted.
Impact of Spatial LAI Heterogeneity on Estimate of Directional Gap Fraction from SPOT-Satellite Data
Authors: Ma Lingling , Li Chuanrong , Tang Bohui , Tang Lingli , Bi Yuyin , Zhou Beiyan , Li Zhao-Liang
Published: June 2008

Directional gap probability or gap fraction is a basic parameter in the optical remote sensing modeling. Although some approaches have been proposed to estimate this gap probability from remotely sensed measurements, few efforts have been made to investigate the scaling effects of this parameter. This paper analyzes the scaling effect through aggregating the high-resolution directional gap probability (pixel size of 20 meters) estimated from leaf area index (LAI) images of VALERI database by means of Beer's law and introduces an extension of clumping index, Ĉ, to compensate the scaling bias. The results show that the scaling effect depends on both the surface heterogeneity and the nonlinearity degree of the retrieved function. Analytical expressions for the scaling bias of gap probability and Ĉ are established in function of the variance of LAI and the mean value of LAI in a coarse pixel. With the VALERI dataset, the study in this paper shows that relative scaling bias of gap probability increases with decreasing spatial resolution for most of land cover types. Large relative biases are found for most of crops sites and a mixed forest site due to their relative large variance of LAI, while very small biases occur over grassland and shrubs sites. As for Ĉ, it varies slowly in the pure forest, grassland and shrubs sites, while more significantly in crops and mixed forest.
The Effect of Sea Surface Slicks on the Doppler Spectrum Width of a Backscattered Microwave Signal
Authors: Karaev Vladimir , Kanevsky Mikhail , Meshkov Eugeny
Published: June 2008

The influence of a surface-active substance (SAS) film on the Doppler spectrum width at small incidence angles is theoretically investigated for the first time for microwave radars with narrow-beam and knife-beam antenna patterns. It is shown that the requirements specified for the antenna system depend on the radar motion velocity. A narrow-beam antenna pattern should be used to detect slicks by an immobile radar, whereas radar with a knife-beam antenna pattern is needed for diagnostics from a moving platform. The study has revealed that the slick contrast in the Doppler spectrum width increases as the radar wavelength diminishes, thus it is preferable to utilize wavelengths not larger than 2 cm for solving diagnostic problems. The contrast in the Doppler spectrum width is generally weaker than that in the radar backscattering cross section; however, spatial and temporal fluctuations of the Doppler spectrum width are much weaker than those of the reflected signal power. This enables one to consider the Doppler spectrum as a promising indicator of slicks on water surface.
Validation and Variation of Upper Layer Thickness in South China Sea from Satellite Altimeter Data
Authors: Lin Chun-Yi , Ho Chung-Ru , Zheng Zhe-Wen , Kuo Nan-Jung
Published: June 2008

Satellite altimeter data from 1993 to 2005 has been used to analyze the seasonal variation and the interannual variability of upper layer thickness (ULT) in the South China Sea (SCS). Base on in-situ measurements, the ULT is defined as the thickness from the sea surface to the depth of 16°C isotherm which is used to validate the result derived from satellite altimeter data. In comparison with altimeter and in-situ derived ULTs yields a correlation coefficient of 0.92 with a slope of 0.95 and an intercept of 6 m. The basin averaged ULT derived from altimeter is 160 m in winter and 171 m in summer which is similar to the in-situ measurements of 159 m in winter and 175 m in summer. Both results also show similar spatial patterns. It suggests that the sea surface height data derived from satellite sensors are usable for study the variation of ULT in the semi-closed SCS. Furthermore, we also use satellite derived ULT to detect the development of eddy. Interannual variability of two meso-scale cyclonic eddies and one anticyclonic eddy are strongly influenced by El Niño events. In most cases, there are highly positive correlations between ULT and sea surface temperature except the periods of El Niño. During the onset of El Niño event, ULT is deeper when sea surface temperature is lower.
An Assessment of the Altimetric Information Derived from Spaceborne SAR (RADARSAT-1, SRTM3) and Optical (ASTER) Data for Cartographic Application in the Amazon Region
Authors: De Oliveira Cleber Gonzales , Paradella Waldir Renato
Published: June 2008

Difficulties in acquiring a complete aerial photography coverage on a regular basis in the Brazilian Amazon due to adverse environmental conditions affect the quality of the national topographic database. As a consequence, topographic information is still poor, and when available needs to be up-dated or re-mapped. In this research, altimetric information derived from RADARSAT-1 (Fine and Standard modes), SRTM3 (3 arcseconds) and ASTER (band 3N-3B) was evaluated for topographic mapping in two sites located in the region: Serra dos Carajás (mountainous relief) and Tapajós National Forest (flat terrain). The quality of the information produced from Digital Elevation Models (DEMs) was evaluated regarding field altimetric measurements. Precise topographic field information acquired from Differential Global Positioning System (DGPS) was used as Ground Control Points (GCPs) for the modeling of the stereoscopic DEMs (RADARSAT- 1, ASTER) and as Independent Check Points (ICPs) for the calculation of accuracies of the products. The accuracies were estimated by comparison of the DEMs values and real elevation values given by ICPs. The analysis was performed following two approaches: (1) the use of Root Mean Square Error (RMSE) for the overall classification of the DEMs considering the Brazilian Map Accuracy Standards (PEC) limits and, (2) calculations of trend analysis and accuracy based on a methodology that takes into account computed discrepancies and standard deviations. The investigation has shown that for flat relief, the altimetric accuracy of SRTM3 and Fine RADARSAT-1 DEMs fulfilled the PEC requirements for 1:100,000 A Class Map. However, for mountainous terrain, only the altimetry of SRTM3 and ASTER fulfilled these requirements. In addition, the performance of ASTER was slightly superior to SRTM3. However it is important to consider the difficulties in the acquisition of good stereo-pairs with optical data in the Amazon and the additional cost (GCPs) to produce ASTER DEMs. Despite showing systematic errors, the findings justify the usage of SRTM3 as a primary elevation source for semi-detailed topographic mapping in the region. It is suggested a combination of altimetry derived for SRTM3 and planimetry extracted from high-resolution SAR (ALOS/PALSAR, TerraSARX, RADARSAT-2) or if available optical data for semi-detailed topographic mapping programs in the Brazilian Amazon, where terrain information is seldom available or presents low quality.