The generation of liquid jets and drops using tightly focused femtosecond laser pulses near a liquid–air interface is a convenient contactless solution for printing functional materials as well as bio-materials. Jets and drops emerge following the nucleation of a cavitation bubble in the liquid bulk by a laser-induced plasma. During the initial expansion of the bubble, a thin and fast jet is produced at the liquid surface. Moments later a second thick and slow jet emanates from the surface when the bubble has nearly deflated. Despite potential applications, little is known about the mechanism behind this complex phenomenology. Here, experiments and simulations are used to investigate this two-jet process. Counter-intuitively, the second jet is not the result of bubble expansion, as with the first jet, but originates from the secondary flows induced by the bubble dynamics. Our study links the second jet properties to the control parameters of the problem and establishes a phase diagram for its emergence.

We summarize a series of numerical experiments of collisional dynamics in dense stellar systems such as globular clusters (GCs) and in weakly collisional plasmas using a novel simulation technique, the so-calledMulti-particle collision (MPC) method, alternative to Fokker-Planck and Monte Carlo approaches. MPC is related to particle-mesh approaches for the computation of self consistent long-range fields, ensuring that simulation time scales with N log N in the number of particles, as opposed to N2 for direct N-body. The collisional relaxation effects are modelled by computing particle interactions based on a collision operator approach that ensures rigorous conservation of energy and momenta and depends only on particles velocities and cell-based integrated quantities.

The stability of symptomatology and of eleven schizophrenic diagnostic systems was studied in patients initially in an acute phase (group 1) compared to patients in a residual phase (group 2). The patients were evaluated over a period of 1 year with a standardized checklist and PANSS in both groups. The number of patients included by the Carpenter, Calego, 1CD9, New-Haven, Schneider and Vienne systems decreased significantly between admission and discharge in group 1, whereas no variation was observed in group 1 between discharge and one year later, or in group 2 over a period of 1 year. The instability of schizophrenic diagnostic systems such as New-Haven, Schneider and Vienne could be due to the variation of positive or general symptomatology. The number of patients included by Feighner or Langfeldt did not vary significantly between admission and discbarge in group 1, in spite of a significant decrease in symptomatology, probably because certain criteria, such as duration of illness, hindered the systems from changing. The results showed the importance of specifying in every study on schizophrenia the time of inclusion (admission, discharge) or the phase of illness (acute or residual phase).

The aim of this study was to test whether a positive and a negative component could be found in broadly defined schizophrenic patients. Therefore, 70 patients either in an exacerbated or in a stabilized phase were selected according to the criteria of at least 1 of the 4 following diagnostic systems: DSM III-R, Schneider, Carpenter, Langfeldt; principal component analyses (PCA) were carried out with the 9 global ratings of the Scales for Assessment of Negative and Positive Symptoms (SANS and SAPS) and with the Positive and Negative Syndrome Scale (PANSS). The PCA of the SANS-SAPS global ratings yielded a 3-factor solution explaining 72.14% of the total variance, depicting a negative, a positive and a disorganization component. The PCA of the PANSS provided a 5-factor solution with a total explained variance of 55.98%. The first 3 factors were similar to those of the SANS-SAPS global rating analysis. The results showed that the positive and negative components described in a homogeneous schizophrenic population could be replicated in a larger and more heterogeneous group of schizophrenic patients. The question regarding the sufficiency of the positive-negative dichotomy was strengthened by the presence of a third disorganization component which explained as much of the variance as the positive component.

Whether studies agree or disagree on the positive-negative dichotomy in schizophrenia, the relevance of a third component, disorganization, remains a point of debate. Disorganization, as expressed by the scale for the assessment of negative symptoms and positive symptoms (SANS-SAPS) and the positive and negative syndrome scale (PANSS) principal-component analyses, could be considered as permanent and determinant a dimension as the positive and negative components. The aim of this study therefore was to determine whether this disorganization, with the negative and positive components, is stable and has the same composition in the acute and postacute phases of illness. This study was carried out in 57 patients, broadly defined by at least one of four diagnostic criteria (American Psychiatric Association, Langfeldt, Carpenter and Schneider), established with a computerized checklist, and evaluated with SANS-SAPS and PANSS. Principal component analyses (PCA) of these scales were performed at admission and discharge from hospital.

The PCA of SANS-SAPS displayed a 3-factor solution, regardless of the phase of illness (acute or postacute), showing that the negative, positive and disorganization components were stable. The PCA of PANSS yielded negative and positive components perfectly stable over time and a disorganization component whose composition varied between admission and discharge. At admission, this component included the conceptual disorganization item negatively correlated with one of depression. At discharge, this disorganization component included two additional items, autistic preoccupation and mannerisms and one depression component appeared. The instability of the PCA of PANSS could express the role played by the phase of illness; in an acute phase, this disorganization component was constituted by more “positive” items such as grandiosity, unusual thought content and active social avoidance whereas in the postacute phase, it included items that reflected more the chronicity of the illness, such as mannerisms and autistic preoccupation. Moreover, the depressive item appeared, in the postacute phase, in a specific depressive component. This result could be due to the fact that depressive symptoms cannot be expressed when positive symptoms are very severe, which explains why no depressive components were shown during the acute phase.

The concordance and degree of overlap between 13 diagnostic systems for schizophrenia, including the five European systems of Berner, Bleuler, Langfeldt, Pull and Schneider, were evaluated in a cross-sectional study (N = 51) taking the phase of illness (acute or residual) into account. The diagnostic assessments were processed by computer using a 183-item standardised checklist and a data-processing program in GW-Basic language. The inter-rater reliability, as assessed by Kappa coefficient, was good to excellent for each diagnostic system established by this method (K from 0.5 to 1). When comparing the concordance between pairs of 13 diagnostic systems for schizophrenia in acute and residual phase groups, results showed that only two significant relationships were not influenced by the phase of illness (Carpenter x RDC; Catego x Schneider), while 24 were. These included only two relationships in the acute group (Carpenter Catego; Carpenter Schneider) and 22 links between pairs of systems in the residual group. In the acute group, no diagnosis of schizophrenia, including duration criteria such as those of DSM III-R, Feighner, Langfeldt, Pull and RDC, was linked to other systems. In the residual group, the operational systems such as Catego, DSM III-R, Feighner, Newhaven, Pull and RDC had more than five relationships with the other systems whereas the non-operational systems of Bleuler, ICD9, Langfeldt and Schneider had less than four relationships with the others. Except Pull's criteria, the European diagnostic systems, in particular Berner's and Bleuler's, seemed to differ from the others because of the few relationships displayed. The results underline the importance of taking the phase of illness into account when comparing between studies utilizing different diagnostic systems for schizophrenia. They also show the relationships between European and international diagnostic systems, insufficiently established so far.

Recently, much effort has been directed towards reaching a consensus on the use of antipsychotic medication in the United Kingdom (UK) and in France. Anecdotal evidence suggests, however, that any differences that may exist between practitioners in the UK are only minor in comparison to those between practitioners in the various countries in the European Union. A comparison was conducted of the number of prescribed antipsychotic compounds, as well as their way of administration, in two samples of schizophrenic patients in the UK and France. French patients were much more likely to have been prescribed two or more antipsychotic compounds, either alone (relative risk: RR = 26.3; 95% CI: 3.8-190.6), or in combination with a depot preparation (RR = ∞; Fisher's exact test P = 0.04). British patients were more likely to have been prescribed a single depot preparation (RR = 4.7; 95% CI: 2.3-9.9). These disparities are related to contrasting views on the properties and indications of antipsychotics in the two countries. Given these disparities, working towards a European consensus appears essential.

The course of negative and positive symptoms was studied in neuroleptic-treated patients over a 3-year period, in consideration also of the initial phase of illness (post-acute or chronic). This study was carried out in a broadly defined schizophrenic sample, in order not to give preference to one diagnostic subgroup over another. Forty-six patients were evaluated every year for 3 years, 23 in the post-acute group and 23 in the chronic group. Aggravations of the Clinical Global Impression (CGI) and of the SANS total score were observed, regardless of the group (chronic or post-acute). This global aggravation confirmed Kraepelin's concept of dementia praecox; moreover, this aggravation was not due to an increase in the number of patients relapsing, or to an aggravation of akinesia. Three types of negative and positive symptom courses were observed: i) the mean sub-scores of positive symptoms, such as hallucinations, delusions, positive formal thought disorders, and of negative symptoms such as flattening affect, avolition/apathy and attentional impairment, did not vary significantly over time in either group; ii) the mean sub-scores of bizarre behavior and alogia fluctuated over time (p < 0.05) and only poverty of speech was perfectly stable among the items constituting alogia; iii) the mean subscores of anhedonia/asociality worsened significantly over time irrespective of the groups (p < 0.05), and among the items constituting anhedonia, recreational interest-activities and intimacy-closeness abilities worsened (p < 0.05 and p < 0.01, respectively). This aggravation was neither due to an increase in neuroleptic doses nor to the duration and chronicity of illness. However, negative symptoms, except anhedonia, can be reversible in some patients. The very strong stability of anhedonia, whatever the group, emphasize the importance of taking anhedonia into account in future diagnostic classifications.

In order to test the hypothesis that an excess of summer births is a risk factor for deficit syndrome, the month of birth was studied in 53 deficit schizophrenic patients compared to 158 non-deficit patients. No significant difference in terms of month of birth or season of birth was observed between deficit and non-deficit patients, suggesting that summer births might not be a risk factor for deficit schizophrenia.

The apolipoprotein E (ApoE) genotype has been found to affect the expression of several neuropsychiatric disorders. We determined ApoE genotype frequencies and their relationship to primary negative symptoms in 61 non-deficit and 45 deficit schizophrenic patients, and compared them with 98 control subjects. No difference was observed when genotype or allele frequencies were compared between the three groups. Our data do not support a role for ApoE in the phenotypic expression of schizophrenia.

Chronic Hallucinatory Psychosis (CHP) is typically a French disease entity initially described by G Ballet (1911) and whose diagnostic criteria were established by Pull (1987). This diagnosis is not used in English and German literature. The aim of this study was to investigate the relationship between Pull's criteria for CHP and the criteria for schizophrenia defined by 14 different diagnostic systems and schizoaffective disorders. Seventy-two non-affective psychotic patients (34 men, 38 women), aged 20 to 84, in exacerbated or stabilized phase, were interviewed by the same investigator (SD). The patient distribution between the diagnoses in the different diagnostic systems was carried out using a computerized 208-item checklist. The main results indicated that the definite CHP diagnosis was significantly related to the Catego S + (C = 0.52; P < 0.01), New-Haven, (C = 0.40; P < 0.05) and Schneider (C = 0.54; P < 0.001) systems for schizophrenia and with the depressive-schizoaffective disorder (C =0.39; P < 0.05) in the RDC system. The probable CHP diagnosis was significantly linked with the same systems and with the probable RDC (C = 0.39; P < 0.05) for schizophrenia. These results emphasize that in 13 out of the 14 diagnostic systems, schizophrenic and schizoaffective disorders overlapped with CHP in the French diagnostic system. Among these systems, four schizophrenic diagnoses were significantly linked to CHP. In contrast, the Bleuler system for schizophrenia was not related to CHP at all.

As no genetic study has been made in deficit patients, characterized by enduring and primary negative symptoms, the aim of the study was to test the involvement of a familial factor in deficit syndrome. The results in 71 schizophrenic patients showed less familial factors but a greater weight in heritage of schizophrenia in deficit than in nondeficit patients.