Soil net nitrogen mineralisation across global grasslands.

Soil nitrogen mineralisation (Nmin), the conversion of organic into inorganic N, is important for productivity and nutrient cycling. The balance between mineralisation and immobilisation (net Nmin) varies with soil properties and climate. However, because most global-scale assessments of net Nmin are laboratory-based, its regulation under field-conditions and implications for real-world soil functioning remain uncertain. Here, we explore the drivers of realised (field) and potential (laboratory) soil net Nmin across 30 grasslands worldwide. We find that realised Nmin is largely explained by temperature of the wettest quarter, microbial biomass, clay content and bulk density. Potential Nmin only weakly correlates with realised Nmin, but contributes to explain realised net Nmin when combined with soil and climatic variables. We provide novel insights of global realised soil net Nmin and show that potential soil net Nmin data available in the literature could be parameterised with soil and climate data to better predict realised Nmin.

Conformational effects on the activity of drugs. 10. Synthesis, conformation, and pharmacological properties of 1-(2,5-dimethoxyphenyl)-2-aminoethanols and their morpholine analogues.

In order to obtain a better understanding of the effects that structural parameters have on the changes of adrenergic activity when 1-aryl-2-aminoethanol derivatives are converted into their corresponding 2-arylmorpholine cyclic analogues, we synthesized 1-(2,5-dimethoxyphenyl)-2-aminoethanol derivatives 5-7 and their morpholine analogues 8-10. The preferred conformation of amino alcohols and their cyclic analogues have been determined through an H NMR and IR study. Compounds 5 and 6 showed both alpha-stimulating and alpha-blocking activity on rat vas deferens, the effect depending on the concentration employed; on the same isolated tissue, N-isopropyl derivative 7 and the morpholine analogues 8-10 exhibited only alpha-blocking activity. As for the beta-adrenergic activity, only the open-chain compound 7 possessed a moderate blocking effect on isolated guinea pig atria. The results of this work seem to indicate that the changes of pharmacological activity involved in the transformation of the adrenergic drugs into their morpholine analogues are influenced more by characteristic features of the aromatic moiety than by the ethanolamine or propanolamine structure of the drugs.

[Effect of chlorimipramine on the so-called ponto-geniculo-occipitalactivity (PGO) in a primate, Papio hamadryas (author's transl)]. / Effet de la chlorimipramine sur l'activité de pointes "ponto-géniculo-occipitales" (PGO) du babouin Papio hamadryas

Three hamadryas adult baboons (female) received 24 daily injections of Chlorimipramine (1.7 mg/kg). The effects on sleep were nearly identical with the effects observed in man. PGO activity, recorded in the lateral geniculate nucleus, was much disturbed. The total number of PGO fell downward from the first recording. The number of PGO/min during paradoxial sleep was even more decreased. This fact suggests a selective influence of CL I on the mechanisms of PGO activity. Is the particular effect of importance to the treatment of depression symptoms?

Electroencephalographic protective action of pyridoxylate during acute hypoxia and subsequent recovery in the rat.

Pyridoxylase at a concentration of 0.6 mmol/kg body weight injected intraperitoneally in rats, increased the resistance of animals to severe hypoxia (O2:3.2%; N2; 96.,%). The electrocorticogram (ECoG) was used to indicate the effectiveness of the drug in lowering the delay of electrographic silence, in 19 control rats and 12 pretreated rats. The ECoG was also recorded period under pure oxygen. In pretreated rats, the ECoG records became flat in a mean time of 551 s, compared with 269 s in the control group. The latent periods of successive steps during cerebral anoxia were significantly delayed in pyridoxylate-pretreated rats subjected to hypoxia. During the recovery period, pyridoxylate improved the recovery of the normal ECoG, particularly when values were expressed as a function of the duration of the hypoxic period. These findings are in good agreement with the significant protection afforded by pyridoxylate on the cerebral rate of energy-rich phosphate bond utilization during hypoxia studied in a separate work.

Effect of pyridoxine, glyoxylic acid and pyridoxylate on oxidative metabolism in vitro and phosphorylated energy-rich compounds studied in rat brains during acute hypoxia and ischaemia.

Pyridoxine (1-8 mmol/l) did not change significantly the cerebral oxygen nor the hypoxic or ischaemic degradation of phosphocreatine and ATP. Glyoxylic acid (1-8 mmol/l), an inhibitor of the citric acid cycle, depressed the electrically stimulated oxygen uptake of brain slices to a lesser extent than did pyridoxylate. Moreover, at concentrations of 0.66 mmol/l, pyridoxylate predominantly delayed the hypoxic or the ischaemic breakdown of creatine phosphate and of ATP compared with glyoxylic acid (0.66 mmol/l). These findings paralleled clearly the prominent hypoxic and post-hypoxic protection afforded by pyridoxylate upon rat brain electrogenesis, reported in the preceding paper.

[Carcinomatous meningitis. Presentation of 3 cases]. / Meningite carcinomatosa. Presentazione di tre casi.

Meningeal carcinomatosis is characterized by diffuse infiltration of the leptomeninges by metastatic cancer in patients usually with a previous history of malignancy. Primary tumors are adenocarcinomas of the breast or lung, or malignant melanoma. The clinical presentation is pleomorphic and commonly affects the cerebral hemispheres, the cranial nerves, or spinal cord and its roots. Diagnosis is confirmed by the presence of the malignant cells in the cerebrospinal fluid (CSF). Computed tomography (CT) and magnetic resonance (MRI) show abnormal findings including ventricular dilatation and small enhancing lesions along the CSF space. Despite radiotherapy and chemotherapy, vital prognosis remains bad and the treatment is useful in improving the quality of life. Three cases presented here emphasize once again the important fact that meningeal carcinomatosis remains a very difficult diagnosis; several lumbar punctures were sometimes necessary, and cerebral fluid studies cannot yet be replaced by other diagnostic techniques like contrast enhanced CT or MRI with gadolinium.

[Experimental study of the toxic convulsant properties of commercial preparations of essences of sage and hyssop (author's transl)]. / Etude expérimentale des propriétés toxiques convulsivantes des essences de sauge et d'hysope du commerce.

Commercial preparations of essences of sage and hyssop have caused poisoning of human beings and were found to possess a convulsant action of central origin in animals. The convulsant effect of hyssop essence appears to be more powerful than that of sage in non-anaesthetized rats. The dose limit, below which the cortical phenomena are subclinical, is 0.08 g/kg for hyssop, while above 0.13 g/kg convulsions appear and become lethal above 1.25 g/kg. The same doses for essence of sage are respectively 0.3, 0.5 and 3.2 g/kg. The neurotoxicity of hyssop appears to be related to the presence of two terpene ketones, pinocamphone and isopinocamphone, the former of which has powerful convulsant properties, and is lethal at doses above 0.05 ml/kg. The toxicity of essence of sage is due to the presence of camphor which is well-known to possess convulsant properties.

Toxicity of some essential plant oils. Clinical and experimental study.

Commercial preparations of essences of sage, hyssop, thuja, and cedar have caused human intoxication in eight cases, from which tonico-clonic convulsions were the major symptom. The experimental study of the toxic properties of commercialized essential oils of sage and hyssop has revealed that their convulsant action was of central nervous system origin in unanesthetized rats, as proven by electrocortical records. The toxicity of the hyssop oil seems to be more powerful than that of sage, since the dose limit from which the cortical events are only subclinical is 0.08 g/kg for hyssop oil and 0.3 g/kg for sage oil. Above 0.13 g/kg for hyssop oil and 0.50 g/kg for sage oil, the convulsions appeared and became lethal above 1.25 g/kg with hyssop oil and 3.2 g/kg with sage oil. The daily repeated injection of subclinical doses revealed the cumulative toxic effect of hyssop oil, since the same low dose induced electrocortical clonic seizures. The toxicity of each oil appeared to be related to the presence of terpenic ketones, camphor in sage commercial oil, camphor and thujone in sage Dalmatian oil, thujone in thuja and cedar oils, and pinocamphone in hyssop oil. The convulsant properties of camphor are well known. The neurotoxicity of thujone and pinocamphone is demonstrated in rats for the first time.

[Interaction between schooling and physiognomic recognition: neuropsychological study in a group of patients with unilateral brain lesions]. / Interazione tra scolarità e riconoscimento fisiognomico: studio neuropsicologico in un gruppo di cerebrolesi unilaterali.

Groups of left-hemisphere damaged patients, right-hemisphere damaged patients and controls were given the facial recognition test of Benton and Van Allen. Educational level was found to be relevant with regard to the performance of the brain damaged groups, such that a difference between left and right hemisphere-damaged groups became apparent only in patients with higher (greater than 5 years) schooling. The implications of the results are discussed.

Um serviço a serviço de alunos de psicologia: a história de um projeto / A service at the service of psychology students: experience in action

Apresenta um projeto desenvolvido no Serviço de Aconselhamento Psicológico do Intituto de Psicologia da Universidade de Säo Paulo, que tem como objetivo a formaçäo do psicólogo. Coloca ser necessário atentar à pessoa do aluno nos 5 anos de sua formaçäo, bem como à pessoa do professor de psicologia e seu lugar como facilitador de aprendizagem do fazer psicológo. Cria um espaço informal de aprendizagem para alunos voluntários (reuniöes semanais de grupo com facilitadores voluntários) e entrevista professores de psicologia. Realiza observaçöes do processo de aprendizagem nos grupos e no trato de depoimentos das experiências de alunos, facilitadores e professores como narrativa. Ambos como forma de busca de sentido mais originário para elaboraçäo do vivido, retomando as dimensöes formativa e informativa constituintes do processo de aprendizagem do psicólogo. Conclui que a compreensäo desse processo pode oferecer elementos para repensar e criar novas formas para a formaçäo do psicólogo visando sua atuaçäo profissional responsável e compromissada com o fazer psicólogo e com o contexto sócio-cultural onde se desenvolve e atua