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The aim of this longitudinal study was to determine whether the depot formulation of an antipsychotic reduces violence in outpatients with schizophrenia as compared to oral administration of the same antipsychotic.
Forty-six previously violent patients with schizophrenia were randomised to receive treatment with oral or depot zuclopenthixol for 1 year. Clinicians interviewed patients at baseline and every month thereafter to assess treatment adherence. An interviewer blinded to treatment assignments interviewed an informant about any violent behaviour during the previous month.
Violence during the follow-up year was inversely proportional to treatment adherence, better compliance, and greater reduction of positive symptoms. Lower frequency of violent acts was observed in the depot group. The level of insight at baseline was not significantly associated with violence recidivism. Regardless of route of administration, treatment non-adherence was the best predictor of violence.
Some patients with schizophrenia and prior violent behaviour may benefit from the depot formulation of antipsychotic medication.
To know prevalence of depression in Spanish nursing home(NH) by analysing the clinical profile of residents from RESYDEM study (Identification of patients with cognitive deterioration and dementia in NH).
A multicentral, transversal, observational study was carried out in April 2005. 71 geriatrician from 54 NH representing the Spanish state participated. Depression was analysed in patient´s history and determined by NPI of Cummings, NH version.
1037 residents were randomized, 1020 were used by clinical data analysis. 941 were used to determine depression prevalence. Median age 83,4yo, 66.6% were women, 70.9% with basic educational level, 57.4% widows, 25.7% single, 41.5% had some degree of functional deterioration, 22.1% had delirium. In 26.4% were documented Stroke(17,9% TIA). 61.7% had dementia.
Depression appears in 31.4% of elderly institutionalized with the only diagnosis of depression or independent of others. There were no significant differences in age groups. However, was most frequent in women. 95.7% of patients with diagnosis of dementia had at least one drug for depression. Most used anti-depressants were trazadone (23%), citalopram (20.9%), sertraline (15.8%), fluoxetine (10.1%). No tricyclical anti-depressant reached 1% of consumption.
Depression affects practically one in three institutionalized elderly in Spain
Institutionalized elderly with depression are largely treated with ISRS. It is believed that the use of trazadone is linked with the effects on sleep and anxiety.
The high prevalence of depression, its overlapping with other processes and the comorbility of residents requires a careful search and approach in NH which implies a challenge for professionals in order to treat it.
Since clinical practice suggests that panic disorder may not be a homogeneous condition, a study was carried out to test the possible existence of different groups or subgroups of panic patients.
Subjects and methods
Thirty-two panic patients (DSM-III-R) underwent lactate challenge in our laboratory and were assessed for heart rate, blood pressure, sweating and Acute Panic Inventory.
During the lactate challenge, patients complaining mainly of ‘cardiorespiratory’ symptoms (N = 12) showed tachycardia and localized sweating. Conversely, patients complaining mainly of ‘pseudoneurological’ symptoms (N = 16) showed bradycardia and generalized sweating. In both groups, Acute Panic Inventory scores were significantly higher during than before the panic attack, but the distribution of the scores was markedly different.
Discussion and Conclusion
The results suggest that panic disorder may be a heterogeneous condition. Implications of these results to other phobic disorders, to Klein’s false suffocation alarm theory and to the ‘extended amygdala model’ are discussed.
Determine the presence of neuropsychiatric symptoms (NPS), using the NPI-NH(Neuropsychiatric Inventory Nursing Home(NH) Version),in order to provide a multidimensional profile in behavioural symptoms in residents and to calculate its prevalence in Spanish NH.
From randomized population of RESYDEM study (Identification of patients with cognitive deterioration and dementia in NH) a multi-central, cross-sectional and observational study was carried out. 71 geriatrician from 54 NH representative the Spanish state participated.NPS was determinated by NPI Cummings NH version. This version includes upsets in sleep and feeding patterns.
992 residents were examined (Median age 83.4yo, 66.6% women, 91.8% received at least one type of treatment, 61.7% with dementia). 523 (52.7%) presented at least one type of NPS. In order of greatest frequency, the following were noted: alterations in sleep patterns (41.7%), depression/disphoria (31.4%), anxiety (31.2%), agitation/aggressiveness (29.6%), apathy/indifference (25.8%), delirious ideas (23.7%), irritability (22.4%), feeding/appetite upsets (18.5%), anomalous motor behaviour (15.3%), hallucinations (13.8%), desinhibition (11.1%), euphoria (4.4%).
35.9% of residents received benzodiapines, 26.7% antidepressants. Atypical neuroleptics were used in 15.8%, in contrast with 7.4% of the use of classic ones.
NPS ´s reached a high prevalence in NH and it is usual that more than one co-exists in the patients.
Alterations in sleep patterns, depression, anxiety, agitation/aggressiveness affect approximately one in three residents.
It is useful and recommendable to evaluate the 12 behavioural areas from the NH version of the NPI scale. This instrument was chosen as a sifting measure to establish neuropyschiatric symptomology in residences.
Depression is highly recurrent in Bipolar patients, causes more disability than other manifestations of the illness and depressive symptoms predominate over manic and hypomanic symptoms. Our aim is to describe whether in our sample we can find some specific differences from the early course of the illness.
33 patients meeting DSM-IV criteria of Bipolar Disorder I and II whose illness onset was less than 5 years from the first Manic/ hyponamic episode or/and less than 10years from the index depressive episode. Recorded variables included socio-demographic, clinical, treatment characteristics and scales (HRSD, YMRS, BPRS, GAF).Analysis was performed using SPSS Version 12.0.
57.6% were male, 42.4% female, mean age 34.42 years. 2 Patients (6.2%) were depressed when inclusion and 8.8% had had a depressive episode before were included in our Program.
The mean number of depressive episodes was 1.88 (SD 3.58). Only 1 patient had had self-harm intent. 15.2% has first degree family history of Unipolar depressive disorder and 20% of Bipolar disorder. 6.2% were hospitalized because a depressive episode.
We found less rates of depressive episodes than we found in the literature with less sub-syndromal and syndromal depressive symptoms than in routine bipolar population that could be explained by the short course of the illness in our sample. More research should be done to study bipolar depression in early phases to find predictors that help us to decrease the high impact it has in the disorder.
Two common approaches to identify subgroups of patients with bipolar disorder are clustering methodology (mixture analysis) based on the age of onset, and a birth cohort analysis. This study investigates if a birth cohort effect will influence the results of clustering on the age of onset, using a large, international database.
The database includes 4037 patients with a diagnosis of bipolar I disorder, previously collected at 36 collection sites in 23 countries. Generalized estimating equations (GEE) were used to adjust the data for country median age, and in some models, birth cohort. Model-based clustering (mixture analysis) was then performed on the age of onset data using the residuals. Clinical variables in subgroups were compared.
There was a strong birth cohort effect. Without adjusting for the birth cohort, three subgroups were found by clustering. After adjusting for the birth cohort or when considering only those born after 1959, two subgroups were found. With results of either two or three subgroups, the youngest subgroup was more likely to have a family history of mood disorders and a first episode with depressed polarity. However, without adjusting for birth cohort (three subgroups), family history and polarity of the first episode could not be distinguished between the middle and oldest subgroups.
These results using international data confirm prior findings using single country data, that there are subgroups of bipolar I disorder based on the age of onset, and that there is a birth cohort effect. Including the birth cohort adjustment altered the number and characteristics of subgroups detected when clustering by age of onset. Further investigation is needed to determine if combining both approaches will identify subgroups that are more useful for research.
To quantify knowledge among the general Spanish population of attention deficit hyperactivity disorder (ADHD).
Material and method:
We developed a telephone-administered questionnaire to ask about ADHD (acronym and full name) on a spontaneous and suggested basis. Questions were asked relating to myths, symptoms, treatment, implications and healthcare professionals involved in the disease.The study sample was 770 adults (sample precision at national level 3.5) with no personal, familial or professional relationship to ADHD.
Only 4% of the subjects spontaneously answered the question about what ADHD means, while 85.3% identified the disease after we suggested what “ADHD” meant. Only 50% admitted that the disease represents a probably genetic brain disorder. A total of 39.6% believed that there was no treatment or healthcare intervention for ADHD. the intervention most often cited as being adequate was psychological treatment (48%), followed by multimodal therapy (44%). Only 12% mentioned medication. Thus, psychological intervention was regarded as the most effective option, followed by psychoeducational measures. Most of the subjects identified the psychologist as the professional indicated to treat ADHD, followed by the pediatrician, psychiatrist and neuropediatrician. Reasonable knowledge was observed in reference to affirmations / myths in ADHD (78.3–95.3%).
There are areas for improvement among the general population regarding knowledge of ADHD, its implications and treatment.
Attention-deficit/hyperactivity disorder (ADHD) is a developmental disorder that persists into adulthood. Though symptoms of inattention and hyperactivity-impulsivity are the two core symptom sets of the disorder, recent reviews argue that emotional dysregulation is an additional feature of ADHD criteria. In the DSM-5 emotional dysregulation does not appear. In a study by the Mental Health Center (MHC) of Arganda, 42 outpatients, all older than 18, we'll look for:
○ Examine the comorbidity of ADHD, in relation to Axis I and personality disorder (PD) from the DSM-IV. In addition, to see if emotional dysregulation is present in these patients.
○ The proposal is that there exist comorbidity with PD, in addition to emotional dysregulation symptoms.
○ Transversal descriptive study of out-patients.
○ A diagnosis of ADHD with: ASRS-V1.1, the ADHD, the CAADID and the WURS scale, reduced version.
○ Emotion dysregulation was assessed by the Impulsivity/Emotional Lability scale from the CAARS and by the DERS and PD with the SCID-II questionary.
A high comorbidity is observed with PD and depressive symptoms. The combined type of ADHD is the most frequently found, with higher severity and frequency of PD. The association with depressive symptoms is more often found in the inattentive subtype and the combined type with substance abuse. Preliminary data is included on emotional dysregulation and ADHD.
ADHD is a disease observed in out-patient adults with a high frequency of comorbidity with PD and depression.
It is necessary to look for the dimension of emotional dysregulation.
This study investigated metabolic, endocrine, appetite and mood responses to a maximal eating occasion in fourteen men (mean: age 28 (sd 5) years, body mass 77·2 (sd 6·6) kg and BMI 24·2 (sd 2·2) kg/m2) who completed two trials in a randomised crossover design. On each occasion, participants ate a homogenous mixed-macronutrient meal (pizza). On one occasion, they ate until ‘comfortably full’ (ad libitum) and on the other, until they ‘could not eat another bite’ (maximal). Mean energy intake was double in the maximal (13 024 (95 % CI 10 964, 15 084) kJ; 3113 (95 % CI 2620, 3605) kcal) compared with the ad libitum trial (6627 (95 % CI 5708, 7547) kJ; 1584 (95 % CI 1364, 1804) kcal). Serum insulin incremental AUC (iAUC) increased approximately 1·5-fold in the maximal compared with ad libitum trial (mean: ad libitum 43·8 (95 % CI 28·3, 59·3) nmol/l × 240 min and maximal 67·7 (95 % CI 47·0, 88·5) nmol/l × 240 min, P < 0·01), but glucose iAUC did not differ between trials (ad libitum 94·3 (95 % CI 30·3, 158·2) mmol/l × 240 min and maximal 126·5 (95 % CI 76·9, 176·0) mmol/l × 240 min, P = 0·19). TAG iAUC was approximately 1·5-fold greater in the maximal v. ad libitum trial (ad libitum 98·6 (95 % CI 69·9, 127·2) mmol/l × 240 min and maximal 146·4 (95 % CI 88·6, 204·1) mmol/l × 240 min, P < 0·01). Total glucagon-like peptide-1, glucose-dependent insulinotropic peptide and peptide tyrosine–tyrosine iAUC were greater in the maximal compared with ad libitum trial (P < 0·05). Total ghrelin concentrations decreased to a similar extent, but AUC was slightly lower in the maximal v. ad libitum trial (P = 0·02). There were marked differences on appetite and mood between trials, most notably maximal eating caused a prolonged increase in lethargy. Healthy men have the capacity to eat twice the energy content required to achieve comfortable fullness at a single meal. Postprandial glycaemia is well regulated following initial overeating, with elevated postprandial insulinaemia probably contributing.
Psychosis spectrum disorder has a complex pathoetiology characterised by interacting environmental and genetic vulnerabilities. The present study aims to investigate the role of gene–environment interaction using aggregate scores of genetic (polygenic risk score for schizophrenia (PRS-SCZ)) and environment liability for schizophrenia (exposome score for schizophrenia (ES-SCZ)) across the psychosis continuum.
The sample consisted of 1699 patients, 1753 unaffected siblings, and 1542 healthy comparison participants. The Structured Interview for Schizotypy-Revised (SIS-R) was administered to analyse scores of total, positive, and negative schizotypy in siblings and healthy comparison participants. The PRS-SCZ was trained using the Psychiatric Genomics Consortiums results and the ES-SCZ was calculated guided by the approach validated in a previous report in the current data set. Regression models were applied to test the independent and joint effects of PRS-SCZ and ES-SCZ (adjusted for age, sex, and ancestry using 10 principal components).
Both genetic and environmental vulnerability were associated with case-control status. Furthermore, there was evidence for additive interaction between binary modes of PRS-SCZ and ES-SCZ (above 75% of the control distribution) increasing the odds for schizophrenia spectrum diagnosis (relative excess risk due to interaction = 6.79, [95% confidential interval (CI) 3.32, 10.26], p < 0.001). Sensitivity analyses using continuous PRS-SCZ and ES-SCZ confirmed gene–environment interaction (relative excess risk due to interaction = 1.80 [95% CI 1.01, 3.32], p = 0.004). In siblings and healthy comparison participants, PRS-SCZ and ES-SCZ were associated with all SIS-R dimensions and evidence was found for an interaction between PRS-SCZ and ES-SCZ on the total (B = 0.006 [95% CI 0.003, 0.009], p < 0.001), positive (B = 0.006 [95% CI, 0.002, 0.009], p = 0.002), and negative (B = 0.006, [95% CI 0.004, 0.009], p < 0.001) schizotypy dimensions.
The interplay between exposome load and schizophrenia genetic liability contributing to psychosis across the spectrum of expression provide further empirical support to the notion of aetiological continuity underlying an extended psychosis phenotype.
Background: Hereditary transthyretin-mediated (hATTR) amyloidosis is a multi-systemic, heterogenous, life-threatening disease. Patisiran resulted in significant improvement in neuropathy and QoL at 18-months compared to placebo, and was generally well-tolerated in the Phase 3 APOLLO study. Methods: Multi-center, OLE study to evaluate the efficacy and safety of long-term patisiran dosing for ≤ 5 years in hATTR amyloidosis patients with polyneuropathy who have completed the APOLLO study (NCT02510261). Endpoints include safety, tolerability and long-term efficacy of patisiran. Measures of clinical benefit are the same endpoints used in APOLLO including changes in mNIS+7 composite neuropathy impairment score and QoL (Norfolk QoL-DN) Results: As of December 2017, 184 of 186 (99%) patients who completed APOLLO and 25 patients from the Ph 2 OLE study enrolled in the Global OLE study. Baseline data for 211(APOLLO/placebo, n=49; APOLLO/patisiran, n=137 and patisiran Ph 2 OLE, n=25) patients included: median age 61 years (26-84); 74% males; 46% V30M. Interim safety data and 12-month efficacy results will be presented. Conclusions: The global OLE study includes a diverse population of hATTR amyloidosis patients. Interim data will include the long-term safety and maintenance of effect in patients continuing on patisiran, as well as the impact of treatment with patisiran on patients previously treated with placebo.
Background: Hereditary transthyretin-mediated (hATTR) amyloidosis a hereditary, multi-systemic and life-threatening disease resulting in neuropathy and cardiomyopathy. In the APOLLO study, patisiran, an investigational RNAi therapeutic targeting hepatic TTR production resulted in significant improvement in neuropathy and QoL compared to placebo and was generally well tolerated. Methods: APOLLO, a Phase 3 study of patisiran vs. placebo (NCT01960348) prespecified a cardiac subpopulation (n=126 of 225 total) that included patients with baseline left ventricular (LV) wall thickness ≥ 13mm and no medical history of aortic valve disease or hypertension. Cardiac measures included structure and function by electrocardiography, changes in NT-proBNP and 10-MWT gait speed. Results: At 18 months, patisiran treatment resulted in a mean reduction in LV wall thickness of 1 mm (p=0.017) compared to baseline, which was associated with significant improvements relative to placebo in LV end diastolic volume (+8.31 mL, p=0.036), global longitudinal strain (-1.37%, p=0.015) and NT-proBNP (55% reduction, p=7.7 x 10-8) (Figure 1). Gait speed was also improved relative to placebo (+0.35 m/sec, p=7.4 x 10-9). Rate of death or hospitalization was lower with patisiran. mNIS+7 results in the cardiac subpopulation will also be presented. Conclusions: These data suggest patisiran has the potential to halt or reverse cardiac manifestations of hATTR amyloidosis.
With the recent discovery of a dozen dusty star-forming galaxies and around 30 quasars at z > 5 that are hyper-luminous in the infrared (μ LIR > 1013 L⊙, where μ is a lensing magnification factor), the possibility has opened up for SPICA, the proposed ESA M5 mid-/far-infrared mission, to extend its spectroscopic studies toward the epoch of reionisation and beyond. In this paper, we examine the feasibility and scientific potential of such observations with SPICA’s far-infrared spectrometer SAFARI, which will probe a spectral range (35–230 μm) that will be unexplored by ALMA and JWST. Our simulations show that SAFARI is capable of delivering good-quality spectra for hyper-luminous infrared galaxies at z = 5 − 10, allowing us to sample spectral features in the rest-frame mid-infrared and to investigate a host of key scientific issues, such as the relative importance of star formation versus AGN, the hardness of the radiation field, the level of chemical enrichment, and the properties of the molecular gas. From a broader perspective, SAFARI offers the potential to open up a new frontier in the study of the early Universe, providing access to uniquely powerful spectral features for probing first-generation objects, such as the key cooling lines of low-metallicity or metal-free forming galaxies (fine-structure and H2 lines) and emission features of solid compounds freshly synthesised by Population III supernovae. Ultimately, SAFARI’s ability to explore the high-redshift Universe will be determined by the availability of sufficiently bright targets (whether intrinsically luminous or gravitationally lensed). With its launch expected around 2030, SPICA is ideally positioned to take full advantage of upcoming wide-field surveys such as LSST, SKA, Euclid, and WFIRST, which are likely to provide extraordinary targets for SAFARI.
Measurements in the infrared wavelength domain allow direct assessment of the physical state and energy balance of cool matter in space, enabling the detailed study of the processes that govern the formation and evolution of stars and planetary systems in galaxies over cosmic time. Previous infrared missions revealed a great deal about the obscured Universe, but were hampered by limited sensitivity.
SPICA takes the next step in infrared observational capability by combining a large 2.5-meter diameter telescope, cooled to below 8 K, with instruments employing ultra-sensitive detectors. A combination of passive cooling and mechanical coolers will be used to cool both the telescope and the instruments. With mechanical coolers the mission lifetime is not limited by the supply of cryogen. With the combination of low telescope background and instruments with state-of-the-art detectors SPICA provides a huge advance on the capabilities of previous missions.
SPICA instruments offer spectral resolving power ranging from R ~50 through 11 000 in the 17–230 μm domain and R ~28.000 spectroscopy between 12 and 18 μm. SPICA will provide efficient 30–37 μm broad band mapping, and small field spectroscopic and polarimetric imaging at 100, 200 and 350 μm. SPICA will provide infrared spectroscopy with an unprecedented sensitivity of ~5 × 10−20 W m−2 (5σ/1 h)—over two orders of magnitude improvement over what earlier missions. This exceptional performance leap, will open entirely new domains in infrared astronomy; galaxy evolution and metal production over cosmic time, dust formation and evolution from very early epochs onwards, the formation history of planetary systems.
Pathological worry is a hallmark feature of generalised anxiety disorder (GAD), associated with dysfunctional emotional processing. The ventromedial prefrontal cortex (vmPFC) is involved in the regulation of such processes, but the link between vmPFC emotional responses and pathological v. adaptive worry has not yet been examined.
To study the association between worry and vmPFC activity evoked by the processing of learned safety and threat signals.
In total, 27 unmedicated patients with GAD and 56 healthy controls (HC) underwent a differential fear conditioning paradigm during functional magnetic resonance imaging.
Compared to HC, the GAD group demonstrated reduced vmPFC activation to safety signals and no safety–threat processing differentiation. This response was positively correlated with worry severity in GAD, whereas the same variables showed a negative and weak correlation in HC.
Poor vmPFC safety–threat differentiation might characterise GAD, and its distinctive association with GAD worries suggests a neural-based qualitative difference between healthy and pathological worries.
Field identification of ST-elevation myocardial infarction (STEMI) and advanced hospital notification decreases first-medical-contact-to-balloon (FMC2B) time. A recent study in this system found that electrocardiogram (ECG) transmission following a STEMI alert was frequently unsuccessful.
Instituting weekly test ECG transmissions from paramedic units to the hospital would increase successful transmission of ECGs and decrease FMC2B and door-to-balloon (D2B) times.
This was a natural experiment of consecutive patients with field-identified STEMI transported to a single percutaneous coronary intervention (PCI)-capable hospital in a regional STEMI system before and after implementation of scheduled test ECG transmissions. In November 2014, paramedic units began weekly test transmissions. The mobile intensive care nurse (MICN) confirmed the transmission, or if not received, contacted the paramedic unit and the department’s nurse educator to identify and resolve the problem. Per system-wide protocol, paramedics transmit all ECGs with interpretation of STEMI. Receiving hospitals submit patient data to a single registry as part of ongoing system quality improvement. The frequency of successful ECG transmission and time to intervention (FMC2B and D2B times) in the 18 months following implementation was compared to the 10 months prior. Post-implementation, the time the ECG transmission was received was also collected to determine the transmission gap time (time from ECG acquisition to ECG transmission received) and the advanced notification time (time from ECG transmission received to patient arrival).
There were 388 patients with field ECG interpretations of STEMI, 131 pre-intervention and 257 post-intervention. The frequency of successful transmission post-intervention was 73% compared to 64% prior; risk difference (RD)=9%; 95% CI, 1-18%. In the post-intervention period, the median FMC2B time was 79 minutes (inter-quartile range [IQR]=68-102) versus 86 minutes (IQR=71-108) pre-intervention (P=.3) and the median D2B time was 59 minutes (IQR=44-74) versus 60 minutes (IQR=53-88) pre-intervention (P=.2). The median transmission gap was three minutes (IQR=1-8) and median advanced notification time was 16 minutes (IQR=10-25).
Implementation of weekly test ECG transmissions was associated with improvement in successful real-time transmissions from field to hospital, which provided a median advanced notification time of 16 minutes, but no decrease in FMC2B or D2B times.
The SPICA mid- and far-infrared telescope will address fundamental issues in our understanding of star formation and ISM physics in galaxies. A particular hallmark of SPICA is the outstanding sensitivity enabled by the cold telescope, optimised detectors, and wide instantaneous bandwidth throughout the mid- and far-infrared. The spectroscopic, imaging, and polarimetric observations that SPICA will be able to collect will help in clarifying the complex physical mechanisms which underlie the baryon cycle of galaxies. In particular, (i) the access to a large suite of atomic and ionic fine-structure lines for large samples of galaxies will shed light on the origin of the observed spread in star-formation rates within and between galaxies, (ii) observations of HD rotational lines (out to ~10 Mpc) and fine structure lines such as [C ii] 158 μm (out to ~100 Mpc) will clarify the main reservoirs of interstellar matter in galaxies, including phases where CO does not emit, (iii) far-infrared spectroscopy of dust and ice features will address uncertainties in the mass and composition of dust in galaxies, and the contributions of supernovae to the interstellar dust budget will be quantified by photometry and monitoring of supernova remnants in nearby galaxies, (iv) observations of far-infrared cooling lines such as [O i] 63 μm from star-forming molecular clouds in our Galaxy will evaluate the importance of shocks to dissipate turbulent energy. The paper concludes with requirements for the telescope and instruments, and recommendations for the observing strategy.
The mid-infrared range contains many spectral features associated with large molecules and dust grains such as polycyclic aromatic hydrocarbons and silicates. These are usually very strong compared to fine-structure gas lines, and thus valuable in studying the spectral properties of faint distant galaxies. In this paper, we evaluate the capability of low-resolution mid-infrared spectroscopic surveys of galaxies that could be performed by SPICA. The surveys are designed to address the question how star formation and black hole accretion activities evolved over cosmic time through spectral diagnostics of the physical conditions of the interstellar/circumnuclear media in galaxies. On the basis of results obtained with Herschel far-infrared photometric surveys of distant galaxies and Spitzer and AKARI near- to mid-infrared spectroscopic observations of nearby galaxies, we estimate the numbers of the galaxies at redshift z > 0.5, which are expected to be detected in the polycyclic aromatic hydrocarbon features or dust continuum by a wide (10 deg2) or deep (1 deg2) blind survey, both for a given observation time of 600 h. As by-products of the wide blind survey, we also expect to detect debris disks, through the mid-infrared excess above the photospheric emission of nearby main-sequence stars, and we estimate their number. We demonstrate that the SPICA mid-infrared surveys will efficiently provide us with unprecedentedly large spectral samples, which can be studied further in the far-infrared with SPICA.
IR spectroscopy in the range 12–230 μm with the SPace IR telescope for Cosmology and Astrophysics (SPICA) will reveal the physical processes governing the formation and evolution of galaxies and black holes through cosmic time, bridging the gap between the James Webb Space Telescope and the upcoming Extremely Large Telescopes at shorter wavelengths and the Atacama Large Millimeter Array at longer wavelengths. The SPICA, with its 2.5-m telescope actively cooled to below 8 K, will obtain the first spectroscopic determination, in the mid-IR rest-frame, of both the star-formation rate and black hole accretion rate histories of galaxies, reaching lookback times of 12 Gyr, for large statistically significant samples. Densities, temperatures, radiation fields, and gas-phase metallicities will be measured in dust-obscured galaxies and active galactic nuclei, sampling a large range in mass and luminosity, from faint local dwarf galaxies to luminous quasars in the distant Universe. Active galactic nuclei and starburst feedback and feeding mechanisms in distant galaxies will be uncovered through detailed measurements of molecular and atomic line profiles. The SPICA’s large-area deep spectrophotometric surveys will provide mid-IR spectra and continuum fluxes for unbiased samples of tens of thousands of galaxies, out to redshifts of z ~ 6.