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Novel experimental data are reported that reveal helical instability formation on imploding z-pinch liners that are premagnetized with an axial field. Such instabilities differ dramatically from the mostly azimuthally symmetric instabilities that form on unmagnetized liners. The helical structure persists at nearly constant pitch as the liner implodes. This is surprising since, at the liner surface, the azimuthal drive field presumably dwarfs the axial field for all but the earliest stages of the experiment. These fundamentally 3D results provide a unique and challenging test for 3D-magnetohydrodynamics simulations. [ABSTRACT FROM AUTHOR]

Multiplex assays often rely on expensive sensors incorporating covalently linked fluorescent dyes. Herein, we developed a self-assembling aptamer-based multiplex assay. This multiplex approach utilizes a previously established split aptamer sensor in conjugation with a novel split aptamer sensor based upon a malachite green DNA aptamer. This system was capable of simultaneous fluorescent detection of two SARS COVID-19-related sequences in one sample with individual sensors that possesses a limit of detection (LOD) in the low nM range. Optimization of the Split Malachite Green (SMG) sensor yielded a minimized aptamer construct, Mini-MG, capable of inducing fluorescence of malachite green in both a DNA hairpin and sensor format., Competing Interests: The authors declare no conflict of interests., (© 2022 The Authors. Published by Elsevier B.V.)

We examined the utility of the Screening Assessment for Gifted Elementary Students (SAGES) for identifying Hispanic gifted students among 162 third through fifth graders, of whom 75% were Anglo-American and 25% Hispanic. Direct discriminant analysis of subscale scores of the SAGES classified 93.2% of the sample as Anglo-American, including 35 of the 41 Hispanic children. This indicated that the subscale scores did not predict group membership. A validation procedure yielded similar results on an independent sample of 25 Anglo-American and 14 Hispanic children. Also, a multivariate profile analysis indicated small score differences between the two groups and reflected similar cognitive processes being assessed. The screening device appears to function fairly within both ethnic groups.

During the period from 1970 to 1975 there were 128 087 confinements in South Australia and 30 maternal deaths were reported, representing a maternal mortality rate of 23 per 100 000 confinements which is lower than in previous reports. Twenty-one deaths were directly due to complications of pregnancy and childbirth, and nine were due to associated conditions. The fall in the maternal mortality rate was largely due to a reduction in the number of deaths from abortion and in the number of confinements to women in the higher-risk older age groups. Infection appeared for the first time as a major cause of maternal death. Avoidable factors may have contributed to 47% of the deaths.

1 A series of compounds structurally related to glutamic acid has been tested on frog and rat spinal neurones. The substances were added to procaine-containing medium bathing the isolated hemiscected spinal cord of the frog, and their potencies in depolarizing motoneurones were assessed by the magnitude of the potential produced in the ventral root. The electrophoretic technique was used to administer the substances around single interneurones of the rat spinal cord and the relative potencies of the compounds as excitants assessed by the magnitude of the currents required to produce similar rates of neuronal firing. 2 Parallel structure-activity relations were observed in the two series of experiments, suggesting that the receptors for excitatory amino acids on frog and rat spinal neurones are similar. 3 Quisqualate, domoate and kainate were the strongest excitants in both animals, with potencies around two orders of magnitude higher than that of L-glutamate. 4 2,4,5-Trihydroxyphenylalanine (6-OH-DOPA) was a stronger excitant and L-3,4-dihydroxyphenylalanine (L-dopa) a weaker excotamt than L-glutamate on frog spinal motoneurones. The former compounds was also a more potent convulsant than L-glutamate on intraventricular injection into mouse brain. The lack of activity of 6-OH-DOPA on electrophoretic administration was attributed to oxidation. 5 Unlike the majority of amino acid excitants, several of the compounds shown in the present work to have moderate excitatory activity are not anionic at physiological pH. This indicates either that two negatively charged groups are not essential for interaction with a common excitatory receptor, or that more than one type of receptor is involved in the actions demonstrated.

The morphology of the cochlear nuclei of normal and reeler mutant mice were studied in Nissl-stained sections. The cochlear nucleus in both mice is divisible into three parts: the anteroventral, posteroventral, and dorsal nuclei. Nine cell types can be recognized in the normal mouse. In the anteroventral nucleus spherical cells occupy the rostral pole. Globular cells are located caudally and extend to the interstitial region of the anteroventral nucleus. In the posteroventral nucleus multipolar cells are located rostrally and dark-staining cells occupy the caudal pole. Multipolar cells are also present in the anteroventral nucleus and in the deep region and molecular layer of the dorsal cochlear nucleus. The dorsal and lateral aspects of the ventral nuclei are covered by a granule cell layer. The dorsal nucleus consists of superficial molecular and pyramidal layers and a deep region. The deep region contains small and giant cells as well as multipolar cells. The pyramidal layer is made up of pyramidal cells, horizontal cells, and granule cells. Small cells are also present in the molecular layer and throughout the ventral nuclei. The dorsal cochlear nucleus of the reeler mutant mouse is disorganized and the molecular layer is reduced in thickness. The organization of the pyramidal layer is disrupted with granule cells superficial to pyramidal and horizontal cells. Cells which appear to be homologous to pyramidal cells are also present in the deep region of the dorsal nucleus. The total number of granule cells is reduced by an average of 42% over the whole nucleus and the reduction in granule cells is greatest in the granule cell cap covering the dorsal and lateral surface of the ventral cochlear nuclei. The cytoarchitecture of the ventral cochlear nucleus appears normal.

A 69-year-old women died of malignant histiocytosis in association with sideroblastic anaemia. Respiratory insufficiency was a prominent clinical feature and was found to be due to obstruction of pulmonary capillaries by malignant histiocytes. It is possible that the same abnormal myeloid clone gave rise to malignant histiocytosis and sideroblastic anaemia.

1 Experiments were performed to determine the effects of intravenously applied bicuculline and strychnine on the click-evoked brain stem auditory evoked potentials (BAEP) of cats. 2 The BAEP was not affected by bicuculline (0.5 mg/kg, i.v.) administration. Strychnine (0.2 mg/kg, i.v.) administration caused a significant increase in the amplitude of peak 4, which is thought to be produced by potentials in the superior olive, lateral lemniscus and inferior colliculus. 3 These results suggest that strychnine blocks glycinergic inhibitory inputs to these auditory structures.

The effects of the dicarboxylic amino acid, DL-alpha-aminoadipate (DLAA) on amino acid responses have been investigated using intracellular recordings from mouse spinal cord neurons grown in dissociated cell culture. DL-alpha-Aminoadipate markedly antagonized postsynaptic responses to iontophoretically appllied aspartate; antagonism of glutamate was much less prominent. DL-alpha-Aminoadipate altered the affinity of aspartate for its receptor while having no observed effects on aspartate-receptor cooperativity. No direct effects of DLAA on membrane potentials or passive membrane properties were seen at the currents used for antagonism. Responses to the inhibitory amino acids GABA and glycine were unaffected by DLAA.

A review has been carried out of patients diagnosed as having coeliac disease some years previously and subsequently lost to follow-up. Most were unaware of the need for continuing treatment and had returned to a normal diet. The resulting morbidity was slight, although one patient had died of a small-bowel lymphoma. If untreated coeliac disease is indeed a pre-malignant condition, then it is suggested that there must be a large population at risk, with no motivation to return to treatment other than the risk of malignancy itself.

Microionophoretically applied excitatory amino acids induced firing of extracellularly recorded single units in a tissue slice preparation of the mouse cochlear nucleus, and the similarly applied antagonist 2-amino-5-phosphonovalerate (2APV) was demonstrated to be a selective N-methyl-D-aspartate (NMDA) receptor antagonist. In addition, the effect of various bath-applied excitatory amino acid receptor antagonists on auditory nerve evoked field potentials was studied. Antagonists which block NMDA type receptors, blocked auditory nerve evoked potentials in a dose-dependent manner. The 50% effective concentration (EC50) for three of the antagonists used was: D-alpha-aminoadipate, 7.8 mM; 2APV, 4.2 mM; and 2,3-cis-piperidine dicarboxylate, 1.1 mM. Glutamate diethylester (5 mM) had no effect. The results suggest that NMDA, kainate and quisqualate receptors are present in the cochlear nucleus and that auditory nerve transmission in the mouse is mediated by an NMDA type receptor. This is consistent with the concept that the auditory nerve postsynaptic receptor in mammals is of the NMDA type.

The behavioural mutant mouse Lurcher survives to adult life as the heterozygote (Lc/+) and shows a disorder of gait. The neurological lesion has been shown to involve degeneration of Purkinje cells and inferior olivary neurones (Caddy and Biscoe 1976). It follows that the climbing fibre input is reduced and we wished to know if the mossy fibre input was also affected. Heterozygote Lurcher mutants were compared with the wild type in all experiments. Mossy fibre glomeruli were identified in the cerebellum of the mutant mouse by electron microscopy. Horseradish peroxidase (HRP) was injected into the cerebellum and was found in the cells of Clarke's column in the spinal cord. Electrophysiological experiments showed that following stimulation of the sciatic nerve evoked responses could be recorded in the cerebellum. It is concluded that the mossy fibre input to the cerebellum is intact in the Lurcher mutant mouse.

In Nissl-stained preparations of the cochlear nucleus there are nine recognizable cell types. These cells are born during three periods of histogenesis prenatally. On gestation days 10.0, 10.5, and 11.0 the pyramidal, giant, and dark-staining cells are born. The spherical, globular, multipolar, and horizontal cells are formed on gestation days 12.0, 12.5, and 13.0 and small cells follow on gestation day 14.5. The onset of granule cell formation is gestation day 14.5 continues to birth on gestation day 19. At birth, and for at least the first 2 postnatal weeks, glial cells are born. There are no regional gradients in cell birth dates, cells from all birth dates being intermixed. Cell birth proceeds in an orderly sequence that is related only to cell size. Although there were no apparent spatiotemporal patterns, some clustering of labeled cells was evident. These observations do not support the hypothesis that Golgi Type I cells precede Golgi Type II cells in their order of birth since both large and small neurons project beyond the nucleus. There is, nonetheless, a sequential pattern in the onset of cell birth for the auditory system, with cochlear nucleus neurons preceding cochlear neurons.

The number and diameter of the motoneurons in serial sections of the facial nucleus in the albino rat were estimated using a photograph-camera lucida technique for counting and measuring cells in conjunction with a systematic section method for sampling the population. The mean diameter of facial motoneuron nucleoli was also estimated. Total cell counts were estimated using two formulas, one a basic count and the other the basic count corrected for split nucleoli errors. The mean motoneuron diameter is 33-93 micronm (+/- 6-18 micronm S.D.). The number and diameter of myelinated axons in both the facial nerve and its cutaneous auricular branch at the level of the stylomastoid foramen were estimated. There are 5353 myelinated axons in the facial nerve, with a mean diameter of 2-74 micronm, and 627 myelinated axons in the cutaneous auricular branch with a mean diameter of 1-47 micronm. The accuracy and reproductibility of results using the photograph-camera lucida technique for counting and measuring cells and the systematic section method of sampling are compared with those of the methods used by previous investigators. The accuracy of results obtained for estimates of the total cell count using the formulas for the basic count and the basic count corrected for split nucleoli are also compared.

The effects of naloxone on potentiation of CA3 pyramidal cell field potentials induced by tetanization of the mossy fiber pathway was studied in the in vitro guinea pig hippocampal slice preparation. Naloxone in nanomolar concentrations prevented the development of long term potentiation and it is concluded that an opioid peptide is probably involved in the generation of the potentiation.

A method of carrying out electrophysiological experiments on the mouse spinal cord is described. The conduction velocity in the spinal dorsal roots (DR) of the normal mouse was in the range 10-100 m sec-1 and in the ventral roots (VR) 50-70 m sec-1. In the dystrophic mutant (129 ReJ dy/dy) the conduction velocity for both roots was usually in the range 0.1-2.0 m sec-1. Reflexes from DR to VR were recorded in both mutant and wild type animals and it was concluded that the delays in the mutant reflex were probably due to the slower conduction velocity in the roots. Postsynaptic inhibition and presynaptic inhibition were demonstrated and records were made from Renshaw cells and intracellularly from motoneurones. Delayed activity in spinal reflex paths, probably of supraspinal origin, was more pronounced in the dystrophic mutant. It is concluded that if the dystrophic mouse mutant were to be regarded as a model for human disease then similar reflex delays should be demonstrated in human subjects with muscular dystrophy.

Experiments were performed on 36 male albino rats anaesthetized with pentobarbitone sodium and paralyzed with gallamine triethiodide. Recordings were made with single and multibarrel glass microelectrodes in the facial nucleus and monopolar silver wire electrodes on the lingual, facial, glossopharyngeal and hypoglossal nerves. The absolute refractory period for facial motoneurones is 2-3 ms, the relative refractory period has a duration of 26-34 ms and the range in axonal conduction velocities is from 15 to 45 m.sec-1. No evidence for afferent fibres in the muscle branches of the facial and hypoglassal nerves could be found. The lingual and glossopharyngeal nerves show reflex connexions with both the facial and hypoglassal nerves. The time courses of the potentiations and depressions of test facial antidromic field potentials following lingual and glossopharyngeal conditioning stimuli are given. Evoked synaptic activity and the distribution of field potentials in the facial mucleus following lingual and glossopharyngeal nerve stimulation are also described. The observed lingual and glossopharyngeal-facial reflexes are discussed with respect to blink reflexes.

The facial nucleus of the rat can be divided into 5 morphological subdivisions. Using a method for the correlation of the observed subdivisions with antidromic field profiles, the orgins of the major muscle branches of the facial nerve in the motor nucleus were determined. The posterior auricular branch is in the medial, the cervical in the ventromedial, the inferior and superior buccolabiales in the lateral, the zygomatic in the dorsal and the temporal and digastric in the intermediate subdivision. The results are consistent with an organization of the motor nucleus reflecting a corresponding topographic organization of the facial musculature.

In a study of 223 consecutive autopsies of subjects older tumours were found in 36 cases (16%) (25/130 males and 11/93 females). Only eight kidneys showed multiple lesions. Renomedullary interstitial cell tumours were correlated with the presence or absence of hypertension and no statistically significant correlation could be demonstrated. The incidence of renomedullary interstitial cell tumours increases with age.

L-Glutamate and L-aspartate were administered electrophoretically near spinal interneurones and Renshaw cells of pentobarbitone-annaesthetized rats. Other spinal interneurones were consistently more sensitive to L-glutamate than to L-aspartate. Renshaw cells, however, showed no consistent difference in their sensitivity to these two amino acids. The results, which are compared with those reported previously in the cat, support the hypothesis that L-glutamate could be a transmitter at spinal primary afferent terminals.

Experiments were performed on 39 male albino rats anaesthetized with pentobarbitone sodium and paralyzed with gallamine triethiodide. Facial motoneurones consistently showed a progressive alteration of spike shape and decrease in spike firing frequency during the continuous microelectrophoretic application of the excitant amino acids D,L-homocysteate, L-glutamate, L-aspartate, and kainate, but infrequently during that of N-methyl-D-aspartate. The relative potencies of these excitants on facial motoneurones are reported. The potential usefulness of N-methyl-D-aspartate to produce amino acid-evoked motoneurone action potentials is discussed. The microelectrophoretically-applied depressant amino acid antagonist strychnine selectively and reversibly blocked the depressant effects of glycine on facial motoneurones. The depression of amino acid-induced firing of facial motoneurones by stimuli to the lingual or glossopharyngeal nerves were reversibly antagonized by microelectrophoretically applied strychnine but not by bicuculline.

The cobalt sulphide precipitation technique, in conjunction with Timm's intensification procedure, was used to delineate the afferent and efferent intramedullary pathways of the seventh cranial nerve complex in the rat. The branchial motor nucleus with the accompanying first part, genu, and second part of the root are described. The motor branches to the superficial facial musculature do not contain fibres of geniculate ganglion origin or fibres which terminate in the spinal trigeminal nucleus. The motor branches to the deep facial muscles arise from the dorsal part of the branchial motor nucleus and traverse to the midline medial to the genu, then project under the genu into the lateral reticular formation before exiting with the facial nerve. The salivatory and lacrimal nuclei and their intramedullary pathways are described. Sensory fibres from the cutaneous auricular branch enter the spinal trigeminal tract and most of the chorda tympani gustatory fibres enter the fasciculus solitarius. A smaller number of gustatory fibres extend medially to the region of the salivatory nucleus. Fibres of greater superficial petrosal origin also enter the fasciculus solitarius as well as the medial reticular formation. These findings are discussed in relation to previous anatomical, physiological and clinical reports.

The spontaneous firing rates of non-prepotential (NPP) units of the anteroventral cochlear nucleus are quite low so it has not been possible to determine whether side band tones are inhibitory when presented alone. Microiontophoretically-applied excitatory amino acids can be used to excite non-spontaneous cells directly. Using this technique it can be shown that side band tone bursts 1/2 to 3/4 octave above the characteristic frequency (CF) of a NPP unit inhibit the amino acid-induced firing. Side band tones which inhibited the amino acid-induced firing were beyond the tuning curve. Side band tones within the tuning curve produced excitation. Both, however, usually reduced the activity evoked by a CF tone burst (i.e., two-tone interaction). The data suggests that lateral inhibition and two-tone interactions are separate phenomena in the auditory system and that lateral inhibition may play a critical role in determining the shape of the tuning curve of NPP units.

Experiments were conducted in the cat anteroventral cochlear nucleus, comparing the actions of strychnine and bicuculline on amino acid-induced depression of spontaneous and evoked firing. Strychnine reduced responses induced by glycine, taurine and beta-alanine more than GABA or muscimol-induced responses. These latter responses were sensitive to bicuculline. Responses to single and paired tone bursts were not sensitive to strychnine or bicuculline applied either iontophoretically or intravenously. The results indicate that the receptors for depressant amino acids are similar to the receptors found in the cat in other brainstem and spinal cord sites, but differ from those found in the cerebellum, thalamus and cerebral cortex. The data also indicate that these amino acids are not involved either in the response to tone bursts at characteristic frequency or in the suppression of this response by a second, higher frequency tone.

A new substnace, quisqualamine, the decarboxylated analogue of quisqualic acid, predictably depressed electrical activity of neurons of the frog and rat spinal cord in vitro and of the mouse spinal cord in vivo. In the in vitro preparations, the action of quisqualamine was associated with a prolonged depolarization of primary afferent terminals which was sensitive to blockade by picrotoxin and bicuculline and which was also depressed by strychnine. This suggests an interaction of quisqualamine with presynaptic receptors for both GABA and beta-alanine. Post-synaptic actions of quisqualamine, which were less marked than those at presynaptic sites, also appeared to be predominantly GABA-mimetic in vitro, though a sensitivity to the GABA-antagonist bicuculline could not be demonstrated in vitro.

Experiments were performed on the nucleus magnocellularis and auditory nerve in tissue slices of 19-20-day-old chick embryos. Bath-applied kainate, quisqualate and N-methyl-D-aspartate induced dose-dependent alterations in the antidromic responses of nucleus magnocellularis neurons. The sensitivity of these agonist-induced responses to 2,3-cis-piperidine dicarboxylate, glutamate diethylester and D-alpha-aminoadipate were tested, as was the sensitivity of auditory nerve transmission. The data suggest that receptors for all three agonists are present on nucleus magnocellularis neurons and that the postsynaptic receptor of the nucleus magnocellularis-auditory nerve synapse is of the kainate type. The effects of bath-applied baclofen were also studied. Baclofen blocked orthodromic responses suggesting that an excitatory amino acid is released from the presynaptic terminal.

Pressures to decrease both turnaround time and operating costs simultaneously have placed conflicting demands on traditional forms of medical transcription. The new technology of voice recognition extends the promise of enabling the pathologist or other medical professional to dictate a correct report and have it printed and/or transmitted to a database immediately. The usefulness of voice recognition systems depends on several factors, including ease of use, reliability, speed, and accuracy. These in turn depend on the general underlying design of the systems and inclusion in the systems of a specific knowledge base appropriate for each application. Development of a good knowledge base requires close collaboration between a domain expert and a knowledge engineer with expertise in voice recognition. The authors have recently completed a knowledge base for surgical pathology using the Kurzweil VoiceReport 5,000-word system.