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Studying tropical hydroclimate and productivity change in the past is critical for understanding global climate dynamics. Northwest Australia is an ideal location for investigating Australian monsoon dynamics, the variability of the Indonesian Throughflow (ITF), and their impact on past productivity and Pacific warm pool evolution, which remain poorly understood during the 40 kyr world in the mid‐early Pleistocene. In this study, we present multi‐proxy records from International Ocean Discovery Program (IODP) Site U1483 in the Timor Sea spanning the last 2,000 ka, including orbitally‐resolved records from the 40 kyr world between 2,000 and 1,300 ka. Our results suggest that northwest Australia underwent a step of increased aridification and that productivity in the Timor Sea declined during the transition from ∼1,700 to ∼1,400 ka. We attribute this aridification to the reduced moisture supply to this region caused by the ITF restriction and warm pool contraction. We ascribe the declined productivity to a decrease in the nutrient supply of the Pacific source water associated with global nutrient redistribution. At orbital timescale, multiple mechanisms, including sea level changes, monsoon, and the Intertropical Convergence Zone (ITCZ) dynamics, and variations in the ITF and Walker circulation could have controlled variations of productivity and terrigenous input in the Timor Sea during the 40 kyr world. Our bulk nitrogen and benthic carbon isotope records suggest a strong coupling to biogeochemical changes in the Pacific during this period. This research contributes to a better understanding of tropical hydroclimate and productivity changes during the 40 kyr world. The northwest Australian region is located at the southwestern edge of the Indo‐Pacific Warm Pool and experiences a seasonal monsoon climate. Oceanic and climate conditions in this region are also strongly influenced by the Indonesian Throughflow (ITF), which is the only tropical pathway in the modern ocean connecting the Pacific and Indian Oceans and providing the main conduit for the exchange of water, salt, and heat between these oceans. These conditions make northwest Australia a strategic location to explore Australian monsoon dynamics, the variability of the ITF, and the interaction between tropical hydroclimate and productivity in the past. However, these processes are poorly documented during the 40 kyr world in the mid‐early Pleistocene, when glacial‐interglacial cycles mainly varied at the 41 kyr obliquity band. Here, we present multiple‐proxy marine records from a site directly impacted by the ITF and we examine terrigenous input and productivity changes in this region over the last 2,000 kyr. Our results suggest that northwest Australia underwent a step of increased aridification and that productivity in the Timor Sea declined during the transition from ∼1,700 to ∼1,400 ka, due to restriction of the ITF, warm pool contraction, and decreased nutrient supply from the Pacific source water. Northwest Australia underwent aridification from ∼1,700 to 1,400 ka due to restricted Indonesian Throughflow and warm pool contractionDecreased productivity in the Timor Sea from ∼1,700 to 1,400 ka reflected decreased nutrient supply from Pacific source waterOrbital variation in productivity and terrigenous input in the Timor Sea during the 40 kyr world are driven by multiple mechanisms Northwest Australia underwent aridification from ∼1,700 to 1,400 ka due to restricted Indonesian Throughflow and warm pool contraction Decreased productivity in the Timor Sea from ∼1,700 to 1,400 ka reflected decreased nutrient supply from Pacific source water Orbital variation in productivity and terrigenous input in the Timor Sea during the 40 kyr world are driven by multiple mechanisms

To investigate whether internuclear ophthalmoparesis (INO) due to demyelination of the medial longitudinal fasciculus (MLF) provides a model for studying the poorly understood symptom of fatigue in multiple sclerosis (MS). We asked whether repetitive horizontal saccades increased eye movement disconjugacy in patients with MS with INO, but not in healthy subjects.

Following monoaural stimulation, long latency auditory evoked potentials (LLAEPs) recorded from contralateral temporal areas have a shorter latency and larger amplitude than those recorded from the ipsilateral temporal areas. This observation agrees with the operational model drawn up in 1967 by Kimura, which assumes that only anatomically prevailing crossed auditory pathways are active during dichotic hearing, while direct pathways are inhibited. The inputs may then be conveyed to the contralateral cortex, from where they finally reach the ipsilateral temporal areas by means of interhemispheric commissures. It is this mechanism which may underline the right ear advantage for verbal stimuli and the left ear advantage for melodies observed when administering dichotic listening tasks. With the aim of verifying this hypothesis, we recorded temporal LLAEPs in a 21 year-old woman suffering from complex partial seizures, whose CT scan and MRI showed corpus callosum agenesia. Our data support the hypothesis that ipsilateral pathways are greatly inhibited by the contralateral pathways, and therefore auditory stimuli can be supposed to reach the contralateral auditory cortex from where they are transferred through the corpus callosum to the ipsilateral auditory cortex.

Most available Italian studies indicate that the prevalence of multiple sclerosis (MS) in Italy is lower than 20 per 100,000. Much higher prevalence figures, however, have been recently found in small communities in Sicily. On this basis, it has been suggested that the frequency of MS in Italy has been seriously underestimated and that the true prevalence for MS is probably similar to that established for northern European countries. This paper reports the results of a survey of MS in the various public health districts of the province of Ferrara. The public health districts are homogeneous medical units serving small populations and therefore represent ideal areas for epidemiological purposes. The total prevalence rate of probable MS for the whole province has been found to be at least 26.9 per 100,000. This result supports the view that the frequency of MS in Italy is higher than that indicated by most published studies, but not that Italy is an area of high risk for MS.

Interaction of tonic labyrinth and neck reflexes was studied in 3 healthy volunteers by analyzing changes in Soleus H-Reflex (SHR) area in relation to both lateral tiltings and neck rotations. By using a Kermath chair each subject was tilted laterally from the vertical to the left and to the right up 15° in steps of 5° and at the same time the longitudinal body axis, keeping the head fixed, was rotated to the right and to the left up to 15° in steps of 5°. All combinations of lateral tiltings and neck rotations were tested. Each test position was followed by a return to 0° for both rotation and tilting (control position). Twelve H-reflexes of right soleus muscle were recorded in each test and control position and the changes in RSHR area were expressed as percentage variations from the mean value absorved in the pretest and post-test control position. Out data indicate that in man, as in animals, labyrinth and neck reflexes act in the opposite direction, and that in the static condition their contribution to postural stabilization is equal. Al fine di studiare nell'uomo le interazioni reciproche dei riflessi tonici labirintici e tonici del collo abbiamo analizzato le variazioni dell'area del riflesso H del muscolo soleo indotte da diverse combinazioni di rotazione del collo ed inclinazioni laterali dell'asse corporeo su 3 soggetti volontari sani. Dalla posizione verticale venivano inclinati lateralmente verso destra e verso sinistra di 5° in 5° fino ad un massimo di 15° e contemporaneamente veniva ruotato l'asse corporeo, tenendo il capo fisso, di 5° in 5° fino ad un massimo di 15°. In ciascun soggetto venivano studiate tutte le possibili combinazioni di inclinazioni e rotazioni. Ogni posizione test veniva fatta seguire da una posizione di controllo a 0° (capo in posizione primaria ed asse corporeo verticale). In ciascuna posizione test e di controllo venivano registrati 12 riflessi H e di ciascuno si misurava l'area. I valori ottenuti nelle diverse posizioni test venivano espressi come percentuale della media dei valori osservati nella corrispondente posizione di controllo precedente e successiva. I risultati così ottenuti indicano che nell'uomo, come nell'animale, i riflessi tonici labirintici e tonici del collo agiscono esercitando sul tono estensorio dell'arto inferiore azioni opposte e di entità sovrapponibile.

Experimental studies in monkeys have demonstrated that injection of gamma-aminobutyric acid (GABA) agonists into the superior colliculus restricts saccadic eye movements, while injection of GABA antagonists leads to square-wave jerks (SWJ). To investigate the role of GABA in saccadic interruptions of fixation, we treated five patients who had SWJ and square-wave oscillations (SWO) with valproic acid (VPA) (2000 mg/d), which has been shown to increase brain GABA levels. VPA effectively reduced the SWJ/SWO in three patients, abolished them in one patient, but was ineffective in the fifth, who had a localized lesion in the cerebellar vermis. VPA effects may have been due to the restoration of the GABAergic tonic inhibitory action from the substantia nigra pars reticulata to the superior colliculus.

On the basis of previous epidemiologic studies, Parkinson disease was thought to be evenly distributed throughout the world. These studies, however, were conducted only on North European populations. The position with regard to the Mediterranean peoples was still unknown, and we therefore studied the frequency of Parkinson disease on the island of Sardinia, where some ethnic groups of the Mediterranean stock are represented. Based on 967 accepted cases, the prevalence per 100,000 population on January 1, 1972, was 65.6; the average annual incidence for the period 1961 through 1971 was 4.9. These figures are one-half of the figures established for North Europeans. Our findings suggest racial differences in predisposition to Parkinson disease. Some Negroid features are present in Sardinians. If, as seems likely, Africans prove to be relatively unsusceptible to the disease, the risk for Sardinians and other Mediterranean ethnic groups might be intermediate between North Europeans and Africans.

In Wilson's disease neurological manifestations result from the damage in the basal ganglia, even if a widespread degeneration of the brain occurs. The few studies performed using evoked potentials with the aim of identifying subclinical dysfunction in the three major sensory pathways have never shown abnormalities in patients without neurological manifestations. To verify this observation we studied 12 patients suffering from Wilson's disease in a pre-neurological stage by using pattern visual evoked potentials (VEPs), somatosensory evoked potentials (SEPs) to median nerve stimulation and brainstem auditory evoked potentials (BAEPs). Four of these patients had not yet been treated with penicillamine or trientine (triethylenetetramine dihydrochloride), while the remaining 8 patients were on treatment for at least 1 year. In 3 patients of this second group and in 1 patient of the first group we observed a significant (3 SD over the mean) increase in P100 wave latency, while SEPs and BAEPs were found to be abnormal in only 1 patient, respectively.

A 47-year-old man developed a persistent form of alexia without agraphia as the result of a haemorrhagic intracerebral lesion in the left inferior temporo-occipital region, due to the rupture of an arteriovenous malformation. Surgical evacuation of the haematoma and excision of the malformation did not produce any modification of the reading deficit, which remained unchanged during a 4-year follow-up. The reading deficit was restricted to words and the patient was able to read only letter-by-letter, so that the whole words were reconstructed from the auditory names of the letters. So far, the disconnection explanation is the standard explanation of alexia without agraphia and the present case of verbal alexia may be regarded as being within this overall category. However, this explanation meets with unanswered questions that suggest more flexible interpretations. Neurolinguistic studies have questioned the unique character of alexia without agraphia as a clinical entity and, in contrast to the disconnection hypothesis, support the notion that the different varieties of alexia that are traditionally described represent distinctive syndromes, each with its own clinical features and pathophysiological basis. In this context, the reading properties in this case seem fully compatible with a deficit of the visual word-form system postulated by Warrington and Shallice, that is, the relatively early stage of the reading process through which a word-form or equivalent unit is attained. This system might be lateralized to the left hemisphere, as suggested by the fact that this case, like other cases of verbal alexia, had sustained damage to the left hemisphere and did not show any differential preservation of the reading of concrete words.

No Abstract.

Quantitative eye movement recordings in a patient with suspected multiple sclerosis who had alternating esotropia, horizontal nystagmus and downbeat nystagmus showed occasional monocular macro square wave jerk intrusions and oscillations in the fixating eye during spontaneous monocular fixation, and binocular macro square wave jerk oscillations during the effort to fuse. Base-out (converging) prisms suppressed nystagmus, oscillopsia, and macro square wave jerks, and restored normal binocular function.

Prevalence studies carried out in Sardinia from 1975 suggest an increasing occurrence of MS. However, it is questionable whether this increase represents a real change in MS incidence or simply reflects longer survival. Data from 79 patients indicated the average annual incidence for the period 1965 through 1985 was 3. 4 per 100, 000. On December 31, 1985, the prevalence rate was 69 per 100, 000. Evaluation of MS temporal trends showed a significant increase in MS incidence during the study period: values ranged around two per 100, 000 in the triennial periods 1965–1967, 1968–1970, and 1971–1973, and around five in each triennium from 197-7 onward.

The comparative geography of multiple sclerosis (MS) and non-neurological diseases considered to be autoimmune is of great interest. But there are few appropriate investigations. Some have found an increase in the frequency of MS, rheumatoid arthritis and rheumatic heart disease depending on the geographic latitude. Nevertheless, the significance of the latitude effect as an indicator of a possible etiological relationship between MS and these conditions has been questioned. In this paper, the frequency of MS, rheumatoid arthritis, rheumatic heart disease and poststreptococcal nephritis is reported from Sardinia where appreciable differences in climatic and socioeconomic conditions exist. There was a positive correlation of the distribution of MS with the distribution of rheumatic heart disease and poststreptococcal nephritis. On the other hand, no correlation was found with the distribution of rheumatoid arthritis.

AbstractInterest in materials for optical storage effect has been intense in the last years. In this paper we report the observation of permanent gratings in a new liquid crystalline side-chain polymer containing a mononuclear cyclopalladated azobenzene complex. Two-beam coupling experiments indicate photorefractive properties. A gain of 900 cm−1, without applied electric field, was determined by two beam coupling measurements. A significant feature of this high gain material is that this effect occurs in an easily processable pure compound.

The tetradentate Schiff base ligands N,N‘-bis[5-(4‘-n-alkyl)phenylazosalicylidene]alkyldiamine H2LN(n) (n = 6, 14), based on 1,2-diaminoethane (N = 1), 1,3-diaminopropane (N = 2), and 1,3-diamino-2,2-dimethylpropane (N = 3) were prepared and characterized. For all the ligands complexes M[LN(n)] (M = Cu, Ni, VO) were readily obtained, which contained two free azo functions. The three series of complexes M[LN(n)] (N = 1−3) were investigated for mesomorphism. This was observed only for N = 1 or 2, in the form of enantiotropic nematic (lower homologues) or smectic (higher homologues) mesophases. The thermal behavior of complexes is discussed on the basis of the structural characteristics of the N,N chelate rings.

We treated 3 multiple sclerosis patients who had pendular nystagmus with isoniazid (800 to 1,000 mg/d). Isoniazid abolished the nystagmus and relieved oscillopsia in 2 patients but was ineffective in the 3rd in whom the nystagmus was damped with convergence and vision improved with converging (base-out) prisms.

Three patients with postural and intention cerebellar tremor caused by a cerebellar infarction in the superior cerebellar artery distribution were studied; treatment with carbamazepine resulted in marked improvement.

Three unusual cases of posterior interosseous nerve palsy involving an entrapment mechanism are described. The findings in these three cases seem to support the view that PIN entrapment usually results from interaction of exogenous factors (occupation, pregnancy, compression during sleep, etc.) with anatomical anomalies at the level of the supinator brevis muscle.

Thin film morphology of tris-(8-hydroxyquinolate) aluminium (III) (Alq3) and bis-(8-hydroxyquinolate) oxovanadium (IV) (VOq2) are compared. Alq3films deposited onto mica at 300K look almost featureless, but dendrimers or randomly distributed needleshaped crystallites appear as a consequence of crystallization in time. We show that a possible origin of this process is exposure to solvent vapors. On the other hand, VOq2films retain their textured morphology as thickness increases because of stabilizing intermolecular interactions between vanadyl groups.

A boy with a left-hemispheric cerebellar astrocytoma had upbeat nystagmus exhibiting increasing-velocity slow phases. The nystagmus improved after excision of the tumour.

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