Synthese, Kristallstruktur und Eigenschaften von Tetraaminophosphonium-iodid P(NH2)4I

Abstract The title compound has been prepared starting from phosphorothionic triamide SP(NH2)3 by methylation of the sulfur atom and subsequent ammonolysis reaction in dry acetonitrile and dichloromethane, respectively, both at room temperature. Suitable single crystals are obtained from an acetonitrile solution in a temperature gradient between 70 °C and room temperature. The crystal structure of [P(NH2)4]I has been determined by single crystal X-ray methods (P4/nbm; a = 842.6(2), c = 486.7(2) pm, Z = 2). In the solid [P(NH2)4]+ - and I−-ions are found with significant N - H···I-hydrogen bonding interactions between anions and cations (H -I: 276.4 pm). The P - N - bond length in the cation (160.7(2) pm) represents the shortest P - NH2 bond distance reported to date indicating a significant electrostatic strengthening. The condensation behaviour of [P(NH2)4]I in solution and in the solid has been investigated.</jats:p

Risk-based life cycle mim strategy for coastal structures - Effect of pre-existing damages on failure probability

A risk-based strategy for monitoring, inspection and maintenance (MIM) is described as a key component of an overall framework for life-cycle engineering and management. Its application for coastal structures is exemplarily outlined for sea/estuary dikes and harbor quay walls. The necessity of the incorporation of pre-existing damages into this strategy is exemplarily illustrated for quay walls, showing how this will affect the failure probability in comparison to a quay wall without any pre-existing damages.German Federal State Lower Saxon

Fundamental research on gluten-free bread

The interest in gluten-free products has increased drastically over the past decades. This is the result of advanced detection methods for gluten-related disorders and the lifestyle choices of consumers. Gluten plays a key role in the production of bread, due to its viscoelastic properties. The replacement of gluten in bread creates a major challenge for producers and scientists to overcome. A literature review as part of this thesis discussed the current state of gluten-free bread and the efforts made to improve it. The quality of gluten-free bread has improved but is still considered to be of poor quality in regard to texture and nutritional value. Based on this review it was concluded that there is a need for a more fundamental understanding of ingredient interactions in a gluten-free bread system. The gained knowledge could help to improve the quality and nutritional value of gluten-free bread. This thesis addresses this issue by characterising commercially available raw materials and their influence on a model bread system (potato starch, HPMC, salt, sugar, yeast, water). Protein supplementation (pea, carob, lupin, potato, soy) in the model bread system affected bread quality parameters, such as specific volume and crumb hardness. Statistical analysis showed strong correlations between the functional properties (foaming, solubility) of the proteins and the bread quality parameters. In addition, the potential of functional ingredients such as hydrocolloids (HPMC, xanthan gum, guar gum, locust bean gum, sodium alginate, pectin) at different concentrations (0.25,0.5, 1.0,1.5,2.0%) to improve the quality of the model bread system was evaluated. It was observed that the addition of sodium alginate and pectin increased the specific volume of the breads in comparison to the HPMC and offered a more consumer-friendly substitute. Furthermore, beer yeast strains of the species Saccharomyces cervisiae were applied to a model bread system (potato starch, pea protein, pectin, salt, sugar, yeast, water). The results generated revealed the potential use of beer yeasts in the model bread system. The activity of yeast, which is affected by temperature and time strongly influenced the size of the baked loaves and correlated with crumb hardness. Lastly, the addition of milled sprouts (amaranth, brown millet, corn, lentil, lupin, pea, quinoa) to improve the nutritional value and its effect on the quality of model-bread system was evaluated. A comprehensive analysis of chemical composition, dough rheology and final bread properties revealed no significant correlations. However, the addition of amaranth caused an improvement of the specific volume and crumb hardness in comparison to a control. The application and combination of the different ingredient groups showed an improvement of the bread formulation in comparison to the starting formulation. The gained fundamental knowledge about the effect of raw material in a gluten-free model bread system opens new opportunities to improve gluten-free bread. The study further suggests raw materials for the use in gluten-free bread production. It also revealed ingredients which could be used to satisfy the demand by consumers for improved nutritional value

THEORETICAL MODEL VALIDATION OF MUSCLE FORCES DURING EXTREME MOVEMENTS

Introduction: The validation of the involved muscular forces for a computer model of the human body, which allows simulation of internal forces in patients, was achieved by inverse-dynamic analysis. Methods: Beginning with an extreme vertical jump, joint moments were extracted from high-speed film data and eventually subdivided into muscular forces. The muscle groups responsible for movements were determined by electromyography. A squat jump with both legs and maximum strength was filmed in the sagittal plane with a frequency of 200 Hz. Moments in the hip, knee and ankle joints were determined from the film data. Using surface electrodes of a Neuraxon Myosoft 2008 system and an amplifier system from Multichannel Systems, the muscle groups responsible for movements were electromyographically determined. The muscle insertions and muscle paths were extracted from MRI pictures of patients. Results: With this information joint moments can be subdivided into single muscle forces. Depending on the jump demands, the muscle groups responsible for movements can be divided and analyzed in six extensor groups. Conclusion: Inverse-dynamic muscle force analysis is a basis which can be expanded for the validation of complex movements under extreme internal loads in patients

Dissociating memory networks in early Alzheimer's disease and frontotemporal lobar degeneration - a combined study of hypometabolism and atrophy

Introduction: We aimed at dissociating the neural correlates of memory disorders in Alzheimer’s disease (AD) and frontotemporal lobar degeneration (FTLD). Methods: We included patients with AD (n = 19, 11 female, mean age 61 years) and FTLD (n = 11, 5 female, mean age 61 years) in early stages of their diseases. Memory performance was assessed by means of verbal and visual memory subtests from the Wechsler Memory Scale (WMS-R), including forgetting rates. Brain glucose utilization was measured by [18F]fluorodeoxyglucose positron emission tomography (FDG-PET) and brain atrophy by voxel-based morphometry (VBM) of T1-weighted magnetic resonance imaging (MRI) scans. Using a whole brain approach, correlations between test performance and imaging data were computed separately in each dementia group, including a group of control subjects (n = 13, 6 female, mean age 54 years) in both analyses. The three groups did not differ with respect to education and gender. Results: Patients in both dementia groups generally performed worse than controls, but AD and FTLD patients did not differ from each other in any of the test parameters. However, memory performance was associated with different brain regions in the patient groups, with respect to both hypometabolism and atrophy: Whereas in AD patients test performance was mainly correlated with changes in the parieto-mesial cortex, performance in FTLD patients was correlated with changes in frontal cortical as well as subcortical regions. There were practically no overlapping regions associated with memory disorders in AD and FTLD as revealed by a conjunction analysis. Conclusion: Memory test performance may not distinguish between both dementia syndromes. In clinical practice, this may lead to misdiagnosis of FTLD patients with poor memory performance. Nevertheless, memory problems are associated with almost completely different neural correlates in both dementia syndromes. Obviously, memory functions are carried out by distributed networks which break down in brain degeneration

MUSCLE ACTIVITY OF THREE SUBJECTS DIFFERING IN WEIGHT AND HEIGHT DURING A VERTICAL JUMP

Introduction: The first measurement was done to evaluate changes of potentials of surface electromyography with different locations of electrode sites and different resistors between the electrodes. The objective of the second was to investigate the activity of muscles in their stimulation sequence, the quantitative participation of the single muscle and cinematic study of vertical jumps. This work is part of a project to determine the internal forces of the human motional apparatus with an anatomical model of muscles. Methods: For each measurement we chose a Noraxon EMG, ECG electrodes from Medicotest, and the electrodes were placed following the description of D.A. Winter. At first we chose the M. gastro. med., M. gastro. lat., and M. soleus of male subject and did a measurement while the subject moved ten times from a ‘standing at attention’ posture to standing on the tips of his toes with a resistor between the electrodes higher than 60 Ohm and one with a resistor lower than 5 Ohm. Then we moved the electrodes 2 cm and 4 cm in the vertical and horizontal directions (resistor of lower than 5 Ohm). Secondly, we chose eight muscles (M. glut. max., M. semitend., M. biceps femoris, M. rectus femoris, M. vastus lat., M. vastus med., M. gastro. med., M. soleus) of three male subjects differing in weight and height and did the measurements while the subjects jumped ten times from a squatting position on a force plate, filmed by a high-speed camera. Results: The measurements with a 60 Ohm resistor and a 5 Ohm resistor differed, as well as the measurements with different locations of electrode sites. The second measurements showed that the M. gas. med. seemed to be the muscle with the highest response, followed by the M. sol. The M. vast. med., M. vast. lat., M. bic. fem. and M. rec. fem. had the same type of reaction. In one case the M. glut. max. seemed to be important while jumping. In an second case the M. semit. showed a high response. The muscles of the tallest subject had the longest activity, and the muscles of the shortest one had the shortest activity. The timedependent angles of knee, hip and foot joints of every subject were nearly identical. Like the EMG, the acceleration phases of the tallest subject took the longest time, while the acceleration phase of the shortest subject took the least time. Conclusions: Firstly, it is possible to see how important the placement and resistor of the electrodes is. Secondly, there is a possible relationship between the beginning of the activity of the muscles and the size of the subjects, as well as a correlation of the angles and the size of the subjects. This effect should be considered in using such calculations of the internal forces of the human motional apparatus in the development of protheses and in sports science

Early Clinical and Radiological Experience with a Ceramic Bone Graft Substitute in the Treatment of Benign and Borderline Bone Lesions

Abstract Substitutes for bone grafts experience increasing popularity, but the need for defect-filling following simple curettage of benign bone lesions is controversial. In this study, we wish to objectively report the radiological changes following bone defect-filling using a composite ceramic bone graft substitute, as well as the clinical results and complications. We evaluated 35 surgically treated benign bone lesions with subsequent defect-filling using two variants of a composite ceramic bone graft substitute (CERAMENT|BONE VOID FILLER or CERAMENT|G, BONESUPPORT AB, SWEDEN). After one year, a normal cortical thickness surrounding the defect was seen in approximately 80% of patients. Inside the defect-cavity, an almost complete product-resorption was seen after one year. The most common complication was a post-operative inflammatory soft-tissue reaction, seen in 7 patients (20%), which resolved without further treatment, although short-term antibiotic treatment was initiated at a local hospital in 6 patients, due to suspected wound infection. In summary, cortical thickness most commonly normalizes after bone tumor removal and filling of the bone defect using this particular composite ceramic bone graft substitute. The ceramic substitute undergoes resorption, which causes progressive changes in the radiological appearance inside the bone defect