Efficacious slosh suppression technique in road tankers to enhance the effectiveness of drinking water distribution.

During summer months, many parts of the world experience the water crisis and water tankers transport fresh drinking water from rivers and other reservoirs and distribute to communities often located at far off places. Effectiveness of this distribution is adversely affected by the instability of tankers due to the phenomenon called liquid sloshing, the oscillation of free liquid surface subjected to external excitation. The liquid within the tank moves along the side walls back and forth creating an oscillation which becomes dangerously worse at certain situations. Sloshing makes the tanker unstable when the operating frequency and the tanker frequency coincides which may even cause the tanker to roll over. Hence, quite often, the tankers have to be operated on roads only at its maximum capacity and the water left in the tank may have to be spilled and wasted if the storage facility at the destination is less than the tanker capacity. In this work we are proposing an optimum design of water tankers to minimize the effect of sloshing and thereby enabling trouble-free operation of the tankers even in partially filled conditions. Sloshing parameters such as slosh height and dynamic wall pressures are experimentally and numerically analyzed for various tank geometries with and without baffles. A numerical model for analyzing slosh parameters is also developed and validated using experimental results. Based on the study an optimized tanker configuration is proposed.

MRI follow-up in syringomyelia. Observations from twelve cases.

In 12 patients syringomyelia was diagnosed using MRI. The underlying cause was a hindbrain hernia in 8 patients, a posterior fossa cyst in one case, and in 3 patients the underlying cause remained unknown. Syringo-subarachnoid shunting in 8 patients failed to decrease pain and the size of the syrinx, motor lesion and gait disturbance in the majority of patients. A cysto-peritoneal shunt in the patient with a posterior fossa cyst and a syringo-peritoneal shunt resulted in a decreasing syrinx and clinical improvement.

Blinded evaluation confirms long-term asymmetric effect of unilateral thalamotomy or subthalamotomy on tremor in Parkinson's disease.

In the past, stereotactic surgery was a regular treatment for prominent unilateral tremor in Parkinson's disease (PD), but follow-up studies were usually short-term and always unblinded. We examined 17 PD patients in long-term follow-up (mean, 10.9 years after surgery) and used videotapes and the Unified Parkinson's Disease Rating Scale to blindly compare tremor ipsilateral and contralateral to the side of surgery. Since the patients were specifically selected for stereotactic surgery because of asymmetric tremor, and the surgical side chosen was contralateral to the predominant tremor, a sign of long-term efficacy would be current postoperative reversal of tremor side predominance. Upper extremity tremor was significantly better contralateral to the surgery compared with the ipsilateral side. We conclude that stereotactic surgery improved the absolute magnitude of tremor or ameliorated its rate of progression. Since asymmetric bradykinesia and dyskinesia were not a prerequisite for the choice of surgical side, we cannot make any conclusion about long-term impact of surgery on these features.

Lesions of the sensorimotor region: somatosensory evoked potentials and ultrasound guided surgery.

In 10 patients with lesions of the sensorimotor cortex cortical SEP were registered to identify the postcentral gyrus, and intra-operative ultrasound sonography served to locate the lesion. The combination of both techniques helped to find the optimal approach to the lesion. Postoperative results were considered favourable, as only one patient suffered transient postoperative deterioration, six were unchanged and in three patients the pre-operative motor deficits were improved. The combination of intra-operative ultrasound and neurophysiological identification of the sensorimotor cortex is concluded as being useful in surgery within this region.

Cerebral reperfusion in brain death of a newborn. Case report.

A case of "sudden infant death" after 15 minutes of successful resuscitation of cardiovascular function is presented. While apnoic cranial nerve areflexia and electrocerebral silence persisted, angiography and transcranial Doppler sonography demonstrated nearly normal cerebral perfusion, which even increased day by day inspite of the persistence of other signs of brain death. The phenomenon "cerebral reperfusion" is concluded to be compatible with the diagnosis of brain death.

Transcranial Doppler sonography and intracranial pressure monitoring in children and juveniles with acute brain injuries or hydrocephalus.

Transcranial Doppler sonography is a noninvasive method of obtaining information about changes in cerebral hemodynamics and intracranial pressure. After severe head injuries the development of brain swelling and brain edema can be assessed and the efficacy of treatment monitored. Development of severe brain edema accompanied by a rapid increase in intracranial pressure can be recognized by a decrease in blood flow velocity and rise in the pulsatility index. In hydrocephalic children the behavior of the cerebral blood flow velocity and the pulsatility index will warn of an increase of the ventricular fluid pressure or a shunt insufficiency.

[Cerebral blood flow velocity. A prognostic factor following severe craniocerebral trauma?]. / Zerebrale Blutflussgeschwindigkeit. Ein prognostischer Faktor nach schweren Schädel-Hirntraumen?

Head injuries lead to changes in cerebral blood flow velocity (BFV)--measured with the transcranial Doppler ultrasonography--in 19 out of 31 patients, i.e. 61%. In 12 cases there was an immediate increase of BFV following the injury or within the first 7 days, often parallel with an increase of the intracranial pressure. On the other hand in 2 out of 4 cases with chronic subdural haemorrhage there was a decrease of the BFV. With routine use of transcranial doppler ultrasound in neurosurgical intensive care, acute changes in BFV along with clinical deterioration may indicate the need for a repeat CT and eventually a surgical intervention.

Cysts of the third ventricle.

Cysts of the third ventricle, predominantly being of congenital origin, are often summarized under the heading of ependymal or neuroepithelial cysts, if they contain an epithelial covering. Though surely they form a heterogeneous group, even by histochemistry and electron microscopy a differentiated classification on a histogenetic basis is difficult because of overlaps in structural details. The aim of this study is checking by immunohistochemistry with antibodies to cytokeratins (KL 1), epithelial membrane antigen (EMA), S 100 protein (S 100), and glial fibrillary acidic protein (GFAP). Fourteen colloid cysts showed clear reaction differences of their epithelium in relation to neuroepithelium, which render feasible the verification of the earlier presumed bronchogenic origin of the former. Two other "ependymal cysts" could be classified as diverticulum respectively meningeal glioependymal cyst. A review is given about localization, clinical and neuroradiological aspects of these partly extreme rare lesions together with differential diagnosis.

Long-term follow-up of children and juveniles with arachnoid cysts.

In the vast literature on intracranial arachnoid cysts, communication of long-term follow-up is rare. Therefore, we studied the case histories of 60 children and juveniles operated on in our hospital since 1951. The most favorable cases were patients with temporal cysts: 93% recovered fully or with only slight deficits. In other locations (frontal, parietal, occipital, infratentorial), the percentages for a favorable course were lower. The reason cannot be attributed to the operation procedures. Independent of the surgical procedure, there were no postoperative deaths after 1969. Long-term follow-up revealed that, depending on the location of the arachnoid cyst, a high percentage (62%-93% of patients) had normal physical and social development with satisfactory quality of life.

Contribution to the problem of giant cell astrocytomas.

Histological, immunocytochemical, and biological features of 38 giant cell gliomas were investigated. The invasion of these tumors and its giant cells by histiocytes, lymphocytes, plasma cells, and especially by eosinophilic granulocytes is viewed as an immune response, which may explain a favorable clinical course. Fifty-three percent of the patients were younger than 45 years at the time of surgery. The average postoperative survival of 27.4 months was clearly longer than in glioblastoma. These biological features suggest a differentiation from glioblastoma multiforme. The classification of this entity as "monstrocellular astrocytoma" is proposed.