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Recent laboratory chamber studies indicate a significant role for highly oxidized low-volatility organics in new particle formation (NPF), but the actual role of these highly oxidized low-volatility organics in atmospheric NPF remains uncertain. Here, particle size distributions (PSDs) measured in nine forest areas in North America are used to characterize the occurrence and intensity of NPF and to evaluate model simulations using an empirical formulation in which formation rate is a function of the concentrations of sulfuric acid and low-volatility organics from alpha-pinene oxidation (Nucl-Org), and using an ion-mediated nucleation mechanism (excluding organics) (Nucl-IMN). On average, NPF occurred on ∼70% of days during March for the four forest sites with springtime PSD measurements, while NPF occurred on only ∼10% of days in July for all nine forest sites. Both Nucl-Org and Nucl-IMN schemes capture the observed high frequency of NPF in spring, but the Nucl-Org scheme significantly overpredicts while the Nucl-IMN scheme slightly underpredicts NPF and particle number concentrations in summer. Statistical analyses of observed and simulated ultrafine particle number concentrations and frequency of NPF events indicate that the scheme without organics agrees better overall with observations. The two schemes predict quite different nucleation rates (including their spatial patterns), concentrations of cloud condensation nuclei, and aerosol first indirect radiative forcing in North America, highlighting the need to reduce NPF uncertainties in regional and global earth system models. [ABSTRACT FROM AUTHOR]

Knowledge of the variations of mass concentration, chemical composition and size distributions of submicron aerosols near roadways is of importance for reducing exposure assessment uncertainties in health effects studies. The goal of this study is to deploy and evaluate an Atmospheric Sciences Research Center-Mobile Laboratory (ASRC-ML), equipped with a suite of rapid response instruments for characterization of traffic plumes, adjacent to the Long Island Expressway (LIE) -- a high-traffic highway in the New York City Metropolitan Area. In total, four measurement periods, two in the morning and two in the evening were conducted at a location approximately 30m south of the LIE. The mass concentrations and size distributions of non-refractory submicron aerosol (NR-PM1) species were measured in situ at a time resolution of 1 min by an Aerodyne High-Resolution Time-of-Flight Aerosol Mass Spectrometer, along with rapid measurements (down to 1Hz) of gaseous pollutants (e.g., HCHO, NO2, NO, O3, and CO2, etc.), black carbon (BC), and particle number concentrations and size distributions. The particulate organics varied dramatically during periods with highest traffic influences from the nearby roadway. The variations were mainly observed in the hydrocarbon-like organic aerosol (HOA), a surrogate for primary OA from vehicle emissions. The inorganic species (sulfate, ammonium, and nitrate) and oxygenated OA (OOA) showed much smoother variations -- with minor impacts from traffic emissions. The concentration and chemical composition of NR-PM1 also varied differently on different days depending on meteorology, traffic intensity and vehicle types. Overall, organics dominated the traffic-related NR-PM1 composition (> 60%) with HOA being the major fraction of OA. The traffic-influenced organics showed two distinct modes in mass-weighted size distributions, peaking at ~ 120 nm and 500 nm (vacuum aerodynamic diameter, Dva ), respectively. OOA and inorganic species appear to be internally mixed in the accumulation mode peaking at ~ 500--600 nm. The enhancement of organics in traffic emissions mainly occurred at ultrafine mode dominated by HOA, with little relation to the OOA-dominated accumulation mode. From Fast Mobility Particle Sizer (FMPS)measurements, a large increase in number concentration at ~10 nm (mobility number mean diameter, Dm) was also found due to traffic influence; though these particles typically contribute a minor fraction of total particle mass. Results here may have significant implications for near-highway air pollution characterization and exposure assessments. Our results suggest that exposure assessments must take into account the rapid variations of aerosol chemistry over short distances near roadways, and also that long-term monitoring of air pollutants throughout the day on different types of days is necessary to accurately gauge exposure to individuals. [ABSTRACT FROM AUTHOR]

The article presents a study which evaluates the use of Hamilton Rating Scale (HRS) for Depression in a general medical in-patient population. HRS was designed to measure the severity of depression in patients already diagnosed as having depressive illness. Here, it was used as part of a comprehensive evaluation of depression in 153 medial in-patients. All the patients had some symptom characteristic of depression as measured by HRS. Though the scores did not match with physician's diagnoses, they correlated as well with scores obtained on the Beck Depression Inventory and with other depressive criteria.

We used the Bond Defense Style and Cloninger Tridimensional Personality questionnaires to assess defense styles and personality dimensions in subjects with anxiety and depressive disorders. When measured against a comparison group, maladaptive defense style scores were significantly higher in those with major depression, panic disorder, generalized anxiety disorder, and social phobia, and higher at a trend level in the subjects with obsessive-compulsive disorder and mixed anxiety and depression. However, there were no differences in adaptive defense style scores between the subjects and the comparison group. The harm avoidance personality dimension scores were significantly higher in subjects with both anxiety and depressive disorders than in the comparison group. The harm avoidance scores correlated positively with the maladaptive defense scores, but negatively with the adaptive defense scores. These findings are discussed in terms of severity of illness, level of functioning, and relationships between Axis I and II disorders.

The State-Trait Anxiety Inventory (STAI) is one of the most widely used scales for the evaluation of anxiety in medical and, to a lesser extent, psychiatric patients. Although there is a relatively large amount of STAI data about anxiety for individuals with a variety of psychiatric disorders, the results of many anxiety studies include only state or trait and many studies have been influenced by comorbidity and by variations in diagnostic criteria used. We studied state and trait anxiety and compared the revised form of the STAI (Form Y) with the original (Form X) to evaluate the anticipated improvement in the measure. In addition, we compared the STAI results with those of another self-report measure (the Symptom Checklist-90 anxiety and depression scales) and also with interviewer-rated measures of anxiety (Hamilton Rating Scale for Anxiety) and depression (Hamilton Rating Scale for Depression). Results indicate that the STAI does not clearly differentiate anxiety disorders from depressive disorders and support the use of multiple tests and of both self-report and interviewer ratings in the evaluation of anxiety and depression in psychiatric patients.

We studied the use of the Symptom Checklist-90 (SCL-90) to differentiate between specific anxiety and depressive disorders and/or their symptoms in 280 patients with 6 DSM-III-R diagnoses: major depression (MD), panic disorder (PD), generalized anxiety disorder (GAD), social phobia (SP), obsessive-compulsive disorder (OCD), and mixed anxiety and depression (MAD). Using a comparison group, we found specific patterns for some of the diagnostic categories. Both the MD and MAD subjects had significantly high paranoid ideation, interpersonal sensitivity, hostility, and psychoticism, as well as high depression subscale scores; those with PD and GAD has the highest anxiety and somatization scores; and those with SP or OCD had a mixed pattern. When ranking the severity of psychopathology, the disorders ordered from most to least were MAD, MD, PD, GAD, SP, and OCD. Subsyndromal levels of symptoms frequently were associated with the various conditions. Use of the SCL-90 subscale helps to enlarge our understanding of the various anxiety and depressive disorders.

We studied Levenson's Internal (I), Powerful Others (P), and Chance (C) locus of control scales in 193 patients with six DSM-III-R diagnoses: Major Depression (MD), Panic Disorder (PD), Generalized Anxiety Disorder (GAD), Social Phobia (SP), Obsessive Compulsive Disorder (OCD), and Mixed Anxiety Depressive Disorder (MAD). Compared to the comparison groups (CG), we found specific patterns for some of the diagnostic categories. There were no significant differences between the I scale scores and of those in the different anxiety and depressive disorder groups and the CG. But, patients with MD, SP, or MAD had significantly higher P scale scores than the CG. Patients with MD, PD, SP, and MAD had higher C scale scores than the CG. The OCD patients had the lowest P and C scale scores of any of the groups and not significantly different than the CG. The findings have some research and clinical implications.

We have examined the numbers and types of symptoms in a sample of 90 patients with generalized anxiety disorder (GAD) and 77 patients with panic disorder (PD) collected from six different sites during the conduct of a multicenter clinical trial. This information was obtained utilizing the Health Questionnaire, a 47-item self-report list of medical symptoms, patterned after the Somatization Disorder section of the Diagnostic Interview Schedule. Although the patients in this sample had a wide variety of medically explained and unexplained physical symptoms, none of them qualified for a diagnosis of somatization disorder by DSM-III-R criteria. GAD and PD patients reported remarkably similar numbers of explained and unexplained medical symptoms. The panoply of somatic symptoms presented by these patients presents a formidable diagnostic challenge for clinicians. These findings suggest that the pattern of overutilization of medical services that is well documented for PD patients may also be found for GAD patients.

The purpose of this study was to determine the utilization of medical specialists by anxiety disorder patients. The setting was a university's clinical outpatient drug trails for anxiety disorders. The participants were subjects identified by advertisement and diagnosed by psychiatric interviews and, in some instances, also by structured interviews. The main outcome measures were the subject responses on a questionnaire listing medical specialists. A total of 94 subjects were surveyed. Primary care physicians (family medicine and internal medicine) were seen more often by panic disorder (PD) subjects than by obsessive-compulsive disorder (OCD) or generalized anxiety disorder (GAD) subjects. Gastroenterologists were seen most frequently by the GAD subjects; dermatologists and cardiologists by the OCD subjects; and otolaryngologists, obstetricians-gynecologists, neurologists, and urologists by the PD subjects. The PD subjects saw more specialists than the subjects with the other disorders. Medical specialists need to increase identification of patients with various anxiety disorders to relieve suffering, improve health care practices, and obtain favorable cost:benefit ratios.

In consulting with anxious medical patients, the psychiatrist needs to consider the possibility of organic disease, differentiate anxiety and depression, and ascertain whether comorbid conditions are present. Guidelines for differential diagnosis are presented. With the anxious patient, treatment goals are to establish rapport, help the patient mobilize intellectual defenses, and enhance self-esteem. Many anxious medical patients will benefit from benzodiazepines, selective serotonin reuptake inhibitors, or doxepin. The therapeutic potential of the consultation is increased by the psychiatrist's meeting with the nursing staff and by a humanistic approach to the patient.

At least 20% of medical patients have anxiety disorders and are in need of treatment, but work with anxious patients is complicated by their distortions and often negative attitudes toward physicians and hospitals. Consultation is complicated by inconsistent referral patterns. Most anxious medical patients accept psychiatric consultation: only 15% to 20% have negative attitudes toward psychiatry. Guidelines for referral are presented.