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Formation of oxidized products from Δ3-carene (C10H16) ozonolysis and their gas-to-particle partitioning at three temperatures (0, 10, and 20 °C) under dry conditions (<2% RH) and also at 10 °C under humid (78% RH) conditions were studied using a time-of-flight chemical ionization mass spectrometer (ToF-CIMS) combined with a filter inlet for gases and aerosols (FIGAERO). The Δ3-carene ozonolysis products detected by the FIGAERO-ToF-CIMS were dominated by semivolatile organic compounds (SVOCs). The main effect of increasing temperature or RH on the product distribution was an increase in fragmentation of monomer compounds (from C10to C7compounds), potentially via alkoxy scission losing a C3group. The equilibrium partitioning coefficient estimated according to equilibrium partitioning theory shows that the measured SVOC products distribute more into the SOA phase as the temperature decreases from 20 to 10 and 0 °C and for most products as the RH increases from <2 to 78%. The temperature dependency of the saturation vapor pressure (above an assumed liquid state), derived from the partitioning method, also allows for a direct way to obtain enthalpy of vaporization for the detected species without accessibility of authentic standards of the pure substances. This method can provide physical properties, beneficial for, e.g., atmospheric modeling, of complex multifunctional oxidation products.

This study investigates the effects of temperature and relative humidity (RH) on the formation of secondary organic aerosol (SOA) from Δ3-carene, a prevalent monoterpene in boreal forests. Dark ozonolysis experiments of 10 ppb Δ3-carene were conducted in the Aarhus University Research on Aerosol (AURA) atmospheric simulation chamber at temperatures of 0, 10, and 20 °C. Under dry conditions (RH < 2%), the SOA formation in terms of both particle number and mass concentration shows minimal temperature dependence. This is in contrast to previous findings at higher initial concentrations and suggests an effect of VOC loading for Δ3-carene. Interestingly, the mass fraction of key oxidation products (cis-3-caric acid, cis-3-caronic acid) exhibit a temperature dependence suggesting continuous condensation at lower temperatures, while evaporation and further reactions over time become more favourable at higher temperatures. The oxygen-to-carbon ratios in the particle phase and the occurrence of highly oxygenated organic molecules (HOM) in the gas phase show modest increases with higher temperatures. Predictions from the Aerosol Dynamics and Gas- and Particle-Phase Chemistry Kinetic Multilayer Model (ADCHAM) agrees with the experimental results regarding both physical particle properties and aerosol composition considering the experimental uncertainties. At high RH (∼80%, 10 °C), a considerable increase in the particle nucleation rate and particle number concentration is observed compared to experiments under dry conditions. This is likely due to enhanced particle nucleation resulting from more stable cluster formation of water and inorganics at increased RH. However, RH does not affect the particle mass concentration.

The Clinical Genome Resource (ClinGen) Consent and Disclosure Recommendation (CADRe) framework proposes that key components of informed consent for genetic testing can be covered with a targeted discussion for many conditions rather than a time-intensive traditional genetic counseling approach. We surveyed US genetics professionals (medical geneticists and genetic counselors) on their response to scenarios that proposed core informed consent concepts for clinical genetic testing developed in a prior expert consensus process. The anonymous online survey included responses to 3 (of 6 possible) different clinical scenarios that summarized the application of the core concepts. There was a binary (yes/no) question asking respondents whether they agreed the scenarios included the minimum necessary and critical educational concepts to allow an informed decision. Respondents then provided open-ended feedback on what concepts were missing or could be removed. At least one scenario was completed by 238 respondents. For all but one scenario, over 65% of respondents agreed that the identified concepts portrayed were sufficient for an informed decision; the exome scenario had the lowest agreement (58%). Qualitative analysis of the open-ended comments showed no consistently mentioned concepts to add or remove. The level of agreement with the example scenarios suggests that the minimum critical educational components for pre-test informed consent proposed in our prior work is a reasonable starting place for targeted pre-test discussions. This may be helpful in providing consistency to the clinical practice of both genetics and non-genetics providers, meeting patients’ informational needs, tailoring consent for psychosocial support, and in future guideline development.

The mechanisms of new particle formation (NPF) events that occurred under high aerosol loadings (“polluted” NPF) in the atmosphere have been unclear, which has inhibited the precision of particle pollution control. To deepen the understanding of how the “polluted” NPF events occur, a one-month comprehensive measurement was conducted in the atmosphere of Beijing during the summer of 2016. The “clean” NPF events (frequency = 22%) (condensation sink, CS < 0.015 s−1) were found to be caused by local nucleation and growth. The “polluted” NPF events (frequency = 28%) (CS > 0.015 s−1) were influenced by both local nucleation-growth and regional transport, and the contributions from the two factors to 6–25 nm particle number concentration were 60% and 40%, respectively. This study emphasized the importance of the transport for nanoparticles in relatively polluted atmospheres, and for that the regional joint particle pollution control would be an essential policy.

Humans adapt to a dynamic environment while maintaining psychological equilibrium. Systems theories of personality hold that generalized processes control stability by regulating how strongly a person reacts to various situations. Research shows there are higher order traits of general personality function (stability) and dysfunction (general personality pathology [GPP]), but whether they capture individual differences in reactivity is largely theoretical. We tested this hypothesis by examining how general personality functioning manifests in everyday life in two samples (Ns = 205 and 342 participants and 24,920 and 17,761 observations) that completed an ambulatory assessment protocol. Consistent with systems theories, we found that (a) there is a general factor reflecting reactivity across major domains of functioning and (b) reactivity is strongly associated with stability and GPP. Results provide insight into how people fundamentally adapt to their environments (or not) and lay the foundation for more practical, empirical models of human functioning.

This paper presents the methods deployed by the Horizon 2O2O SCIPPER project to characterize emission performance of vessels, mainly under the perspective of checking compliance to new emissions regulations. Various on-board and remote measurement techniques have been demonstrated within five experimental campaigns conducted at Europe's main sea areas and ports. Almost a thousand of ship plumes has been measured and crossed checked with various instrumentation, revealing the emission profile of ships during actual operation Accuracy of each measurement technique was also tested. Emission measurements are further exploited to assess the impact of shipping on air quality of coastal areas, by identifying the transformations of pollutants performed in the atmosphere as plume evolves and quantifying onshore pollutants concentrations attributed to shipping activity.

Biomass burning is a growing alternative to fossil fuels for power generation. Small-scale residential wood combustion introduces air pollutants to local populated areas compared to remote, large-scale facilities. Pellet fuel appliances are an alternative to log burning as they are considered more efficient; however, as emissions are not as well characterized, comparative studies to establish the potential benefits of increased pellet stove usage is required. Here we describe a distinction in optical and chemical properties of emissions from a residential pellet and a log-burning stove using state-of-the-art online measurements. Specifically, we report the first online simultaneously phase-resolved semi-volatile organic measurements from such appliances, using a Time of Flight Chemical Ionisation Mass Spectrometer with a Filter Inlet for Gas and AEROsols (FIGAERO-ToF-CIMS). Pellet particle emissions were 90% brown carbon-containing substituted mono-aromatic compounds (SMAs) whereas wood emissions contained equal black carbon (BC) and organic carbon (OC) and contained 3–55 times more poly-aromatic hydrocarbons (PAHs). Lowering pellet fuel loadings increased OC and SMA emission factors (EFOCand EFSMA), therefore increasing particle mass as well as optical absorption, i.e.“brownness”. The consequence of these EF differences is illustrated for a hypothetical national burden assuming a base case 10 : 1 log to pellet stove energy demand usage and a ‘swapped’ demand to simulate increased pellet stove usage. This results in net decreases of PM and BC burdens by 12% and 42% respectively but is somewhat offset by a 57% increase in OC burden. Changes in phase resolved speciated organic EFs suggest the reduction in particle burdens is somewhat offset by increases in gas burdens for some organic species, which could contribute to delayed particle burdens through secondary aerosol formation.

In this longitudinal study, we examined whether personality traits moderate the link between interpersonal dysfunction and suicidal behavior in a high-risk sample of 458 individuals diagnosed with borderline personality disorder. Participants were assessed annually for up to 30 years (mean number of follow-ups = 7.82). Using multilevel structural equation modeling, we examined (a) longitudinal, within-persons relationships among interpersonal dysfunction, suicidal ideation, and suicide attempts and (b) moderation of these relationships by negative affectivity and disinhibition. Negative affectivity predicted a stronger within-persons coupling between interpersonal dysfunction and suicidal ideation. Disinhibition predicted a stronger coupling between ideation and suicide attempts. Assessing negative affectivity and disinhibition in a treatment setting may guide clinician vigilance toward people at highest risk for interpersonally triggered suicidal behaviors.

In this commentary, we discuss questions and misconceptions about the Hierarchical Taxonomy of Psychopathology (HiTOP) raised by Haeffel et al. We explain what the system classifies and why it is descriptive and atheoretical, and we highlight benefits and limitations of this approach. We clarify why the system is organized according to patterns of covariation or comorbidity among signs and symptoms of psychopathology, and we discuss how it is designed to be falsifiable and revised in a manner that is responsive to data. We refer to the body of evidence for HiTOP’s external validity and for its scientific and clinical utility. We further describe how the system is currently used in clinics. In sum, many of Haeffel et al.’s concerns about HiTOP are unwarranted, and for those concerns that reflect real current limitations of HiTOP, our consortium is working to address them, with the aim of creating a nosology that is comprehensive and useful to both scientists and clinicians.

•The rise of functional neuroimaging has led to increasing attempts to link personality traits directly to neural correlates.•Identifying the neural correlates of personality traits does little to explain individual differences.•Transitioning to an explanatory personality neuroscience will require empirical work that bridges multiples levels of analysis and integrates careful behavioral experimentation into large samples.

The Hierarchical Taxonomy of Psychopathology (HiTOP) is a quantitative nosological system that addresses shortcomings of traditional mental disorder diagnoses, including arbitrary boundaries between psychopathology and normality, frequent disorder co‐occurrence, substantial heterogeneity within disorders, and diagnostic unreliability over time and across clinicians. This paper reviews evidence on the validity and utility of the internalizing and somatoform spectra of HiTOP, which together provide support for an emotional dysfunction superspectrum. These spectra are composed of homogeneous symptom and maladaptive trait dimensions currently subsumed within multiple diagnostic classes, including depressive, anxiety, trauma‐related, eating, bipolar, and somatic symptom disorders, as well as sexual dysfunction and aspects of personality disorders. Dimensions falling within the emotional dysfunction superspectrum are broadly linked to individual differences in negative affect/neuroticism. Extensive evidence establishes that dimensions falling within the superspectrum share genetic diatheses, environmental risk factors, cognitive and affective difficulties, neural substrates and biomarkers, childhood temperamental antecedents, and treatment response. The structure of these validators mirrors the quantitative structure of the superspectrum, with some correlates more specific to internalizing or somatoform conditions, and others common to both, thereby underlining the hierarchical structure of the domain. Compared to traditional diagnoses, the internalizing and somatoform spectra demonstrated substantially improved utility: greater reliability, larger explanatory and predictive power, and greater clinical applicability. Validated measures are currently available to implement the HiTOP system in practice, which can make diagnostic classification more useful, both in research and in the clinic.

The Indo-Gangetic Plain (IGP) region of India faces some of the most severe air pollution problems on Earth that threaten human health, food security, ecosystems, environmental sustainability, and the climate. The aim of this study is to identify and characterize the sources of key short-lived climate pollutants (SLCPs) – black carbon (BC), brown carbon (BrC), and ozone (O3) – as well as other pollutants [carbon monoxide (CO) and nitrogen oxides NOX= NO and NO2], and interlinked atmospheric processes of their formation and transformation at our long-term air pollution monitoring station in a remote rural IGP site, the Indo-Gangetic Plains Centre for Air Research and Education (IGP-CARE). Because of its location, measurements acquired at IGP-CARE provide otherwise new information on the key SLCPs in the IGP region at a remote and rural location. The year-long measurement data at this remote site provided new insights into the variability of SLCP concentration and interlinked atmospheric processes that affect air quality in the rural IGP region. Thirteen episodic events (E1–E13) of elevated BC and BrC concentrations were identified, which can largely be attributed to the local biomass burning activities in the neighboring rural communities. It is suggested that high concentrations of BrC were mostly primary in nature and thought to be co-emitted with BC from biomass burning. Also, secondary pollutant tropospheric O3showed elevated concentration. O3peaks were mostly attributed to local ozone formation. Nevertheless, on several occasions, O3emission was also attributed to regional urban areas. This study's most important finding is that BrC concentrations were relatively high throughout the year with very pronounced diurnal variation with distinct morning and evening peaks in general and a minimum at around noon time; this is hypothesized to be associated with daytime photochemical processes. Analyses using a conditional bivariate probability function (CBPF) and potential source contribution function (PSCF) suggest that regional sources likely affected the local concentrations of SLCPs. These results partly explain the high concentrations and spatial distributions of SLCPs at the local and regional scales at the IGP-CARE site in winter and autumn. In contrast, in the summer and monsoon seasons, strong convection likely favored the dilution of pollutants.

Aerosol mass spectrometry was used to characterize submicron aerosols before and after aging in a Gothenburg Potential Aerosol Mass (Go:PAM) reactor at two suburban sites in China, one in northern China at Changping (CP), Beijing, and a second in southern China at Hong Kong (HK). Organic aerosol (OA) dominated in the ambient nonrefractory particulate matter <1 μm (NR‐PM1) for both CP (42–71%) and HK (43–61%), with a large contribution from secondary OA factors that were semivolatile oxygenated (SVOOA) and low‐volatility oxygenated (LVOOA). Under constant OH exposure, OA enhancement (78–98%) dominated the NR‐PM1mass increment at both sites, while nitrate was enhanced the most among the inorganic species (7–9%). Overall, the CP site exhibited higher OA oxidation potential and more enhancement of SVOOA than LVOOA (7.5 vs. 2.7 μg/m3), but the reverse was observed in HK (0.8 vs. 2.6 μg/m3). In CP, more enhancement of the less oxygenated SVOOA suggests that aerosol aging was more sensitive to the abundant locally emitted primary OA and volatile organic compound precursors. On the contrary, the more formation of the highly oxidized LVOOA in HK indicates that aerosol aging mainly escalated the degree of oxygenation of OA as ambient aerosol was already quite aged and there was a lack of volatile organic compound precursors. The comparative measurements using the same oxidation system reveal distinct key factors and mechanisms that influence secondary aerosol formation in two suburban locations in China, providing scientific insights to assist formulation of location‐specific mitigation measures of secondary pollution. Atmospheric submicron particles have significant impacts on the climate and human health. A large part of these particles are formed secondarily through successive aging of primary emissions. To study such aging processes, we used a reactor that can provide highly oxidizing conditions to simulate the oxidation of ambient aerosols at accelerated rates. An online mass spectrometer was connected after the reactor to measure changes in aerosol mass concentration and chemical composition between the ambient samples and the oxidized ones. We presented the first comparative measurements of the aging potentials of ambient aerosols in two suburban sites in northern and southern China (Changping District in Beijing, and Hong Kong). Results showed that generally aerosols at the Changping site had higher aging potentials after passing through the oxidation reactor, probably due to more local emissions of precursors, while air masses in Hong Kong were already in a higher oxidation state with lower aging potentials, mainly because of strong impacts from long‐range transported pollution sources. Distinct aerosol aging pathways related to different ambient precursors were observed at the two sites. Understanding of the different characteristics of aerosol aging processes can lead to advances in air quality modeling and pollution management. Aging processes of submicron nonrefractory aerosols were investigated comparatively at two suburban sites in northern and southern ChinaBoth sites showed dominant mass increment from organics after aging, but aerosols in northern China had higher aging potentialThe distinct aging processes at the two sites reflected influence from ambient precursors

The OH-initiated degradation of 2-amino-2-methyl-1-propanol [CH3C(NH2)(CH3)CH2OH, AMP] was investigated in a large atmospheric simulation chamber, employing time-resolved online high-resolution proton-transfer reaction-time-of-flight mass spectrometry (PTR-ToF-MS) and chemical analysis of aerosol online PTR-ToF-MS (CHARON-PTR-ToF-MS) instrumentation, and by theoretical calculations based on M06-2X/aug-cc-pVTZ quantum chemistry results and master equation modeling of the pivotal reaction steps. The quantum chemistry calculations reproduce the experimental rate coefficient of the AMP + OH reaction, aligning k(T) = 5.2 × 10–12× exp (505/T) cm3molecule–1s–1to the experimental value kexp,300K= 2.8 × 10–11cm3molecule–1s–1. The theoretical calculations predict that the AMP + OH reaction proceeds via hydrogen abstraction from the −CH3groups (5–10%), −CH2– group, (>70%) and −NH2group (5–20%), whereas hydrogen abstraction from the −OH group can be disregarded under atmospheric conditions. A detailed mechanism for atmospheric AMP degradation was obtained as part of the theoretical study. The photo-oxidation experiments show 2-amino-2-methylpropanal [CH3C(NH2)(CH3)CHO] as the major gas-phase product and propan-2-imine [(CH3)2C═NH], 2-iminopropanol [(CH3)(CH2OH)C═NH], acetamide [CH3C(O)NH2], formaldehyde (CH2O), and nitramine 2-methyl-2-(nitroamino)-1-propanol [AMPNO2, CH3C(CH3)(NHNO2)CH2OH] as minor primary products; there is no experimental evidence of nitrosamine formation. The branching in the initial H abstraction by OH radicals was derived in analyses of the temporal gas-phase product profiles to be BCH3/BCH2/BNH2= 6:70:24. Secondary photo-oxidation products and products resulting from particle and surface processing of the primary gas-phase products were also observed and quantified. All the photo-oxidation experiments were accompanied by extensive particle formation that was initiated by the reaction of AMP with nitric acid and that mainly consisted of this salt. Minor amounts of the gas-phase photo-oxidation products, including AMPNO2, were detected in the particles by CHARON-PTR-ToF-MS and GC×GC-NCD. Volatility measurements of laboratory-generated AMP nitrate nanoparticles gave ΔvapH= 80 ± 16 kJ mol–1and an estimated vapor pressure of (1.3 ± 0.3) × 10–5Pa at 298 K. The atmospheric chemistry of AMP is evaluated and a validated chemistry model for implementation in dispersion models is presented.

The phase states of primarily emitted and secondarily formed aerosols from gasoline vehicle exhausts were investigated by quantifying the particle rebound fraction (f). The rebound behaviors of gasoline vehicle emission-related aerosols varied with engines, fuel types, and photochemical aging time, showing distinguished differences from biogenic secondary organic aerosols. The nonliquid-to-liquid phase transition of primary aerosols emitted from port fuel injection (PFI) and gasoline direct injection (GDI) vehicles started at a relative humidity (RH) = 50 and 60%, and liquefaction was accomplished at 60 and 70%, respectively. The RH at which fdeclined to 0.5 decreased from 70 to 65% for the PFI case with 92# fuel, corresponding to the photochemical aging time from 0.37 to 4.62 days. For the GDI case, such RH enhanced from 60 to 65%. Our results can be used to imply the phase state of traffic-related aerosols and further understand their roles in urban atmospheric chemistry. Taking Beijing, China, as an example, traffic-related aerosols were mainly nonliquid during winter with the majority ambient RH below 50%, whereas they were mostly liquid during the morning rush hour of summer, and traffic-related secondary aerosols fluctuated between nonliquid and liquid during the daytime and tended to be liquid at night with increased ambient RH.

China has large anthropogenic chlorine emissions from agricultural fires, residential biofuel, waste incineration, coal combustion, and industrial processes. Here we quantify the effects of chlorine on fine particulate matter (PM2.5) and ozone air quality across China by using the GEOS-Chem chemical transport model with comprehensive anthropogenic emissions and detailed representation of gas-phase and heterogeneous chlorine chemistry. Comparison of the model to observed ClNO2, HCl, and particulate Cl–concentrations shows that reactive chlorine in China is mainly anthropogenic, unlike in other continental regions where it is mostly of marine origin. The model is successful in reproducing observed concentrations and their distributions, lending confidence in the anthropogenic chlorine emission estimates and the resulting chemistry. We find that anthropogenic chlorine emissions increase total inorganic PM2.5by as much as 3.2 μg m–3on an annual mean basis through the formation of ammonium chloride, partly compensated by a decrease of nitrate because ClNO2formation competes with N2O5hydrolysis. Annual mean MDA8 surface ozone increases by up to 1.9 ppb, mainly from ClNO2chemistry, while reactivities of volatile organic compounds increase (by up to 48% for ethane). We find that a sufficient representation of chlorine chemistry in air quality models can be obtained from consideration of HCl/Cl–thermodynamics and ClNO2chemistry, because other more complicated aspects of chlorine chemistry have a relatively minor effect.

Water and organics are omnipresent in the atmosphere, and their interactions influence the properties and lifetime of both aerosols and clouds. Nopinone is one of the major reaction products formed from β-pinene oxidation, a compound emitted by coniferous trees, and it has been found in both gas and particle phases in the atmosphere. Here, we investigate the interactions between water molecules and nopinone surfaces by combining environmental molecular beam (EMB) experiments and molecular dynamics (MD) simulations. The EMB method enables detailed studies of the dynamics and kinetics of water interacting with solid nopinone at 170–240 K and graphite coated with a molecularly thin nopinone layer at 200–270 K. MD simulations that mimic the experimental conditions have been performed to add insights into the molecular-level processes. Water molecules impinging on nopinone surfaces are efficiently trapped (≥97%), and only a minor fraction scatters inelastically while maintaining 35–65% of their incident kinetic energy (23.2 ± 1.0 kJ mol–1). A large fraction (60–80%) of the trapped molecules desorbs rapidly, whereas a small fraction (20–40%) remains on the surface for more than 10 ms. The MD calculations confirm both rapid water desorption and the occurrence of strongly bound surface states. A comparison of the experimental and computational results suggests that the formation of surface-bound water clusters enhances water uptake on the investigated surfaces.

Suicide is linked to impaired value-based decision-making and impulsivity, but whether these risk factors share neural underpinnings is unclear. Disrupted ventromedial prefrontal cortex (vmPFC) value signals may underlie this behavioral phenotype. We investigated vmPFC value signals, vmPFC–frontoparietal connectivity, and the impact of impulsivity during decision-making in depressed individuals with and without suicidal behavior. Middle-aged and older adults (n= 116; 35 with a history of suicide attempts, 25 with ideation only, 25 depressed controls with no ideation, and 31 nonpsychiatric controls) completed a decision-making task with drifting reward probabilities during fMRI. Values of choices, estimated by a reinforcement learning model, were regressed against BOLD signal. VmPFC value activation was compared between groups. Moderating effects of impulsivity on vmPFC–frontoparietal connectivity were assessed in nonpsychiatric controls and compared among patient groups. VmPFC value responses in participants with a history of suicide attempts were reduced relative to nonpsychiatric controls (p< 0.05). In nonpsychiatric controls, vmPFC–frontoparietal connectivity was negatively moderated by impulsivity (pFWE corrected< 0.05). This effect was preserved in comparison patient groups but abolished in suicide attempters (p< 0.001). This change in neural connectivity patterns also affected behavior: people with a history of suicide attempts showed a disrupted effect of vmPFC–frontoparietal connectivity, impulsivity, and reinforcement on choice quality (p< 0.001). These effects were specific to vmPFC and not to striatum. In summary, findings from this study largely support disrupted vmPFC value signals in suicidal behavior. In addition, it uncovers an altered pattern of vmPFC–frontoparietal connectivity in impulsive people with suicidal behavior, which may underlie disrupted choice processes in a suicidal crisis.

Secondary organic aerosol contributes to the atmospheric particle burden with implications for air quality and climate. Biogenic volatile organic compounds such as terpenoids emitted from plants are important secondary organic aerosol precursors with isoprene dominating the emissions of biogenic volatile organic compounds globally. However, the particle mass from isoprene oxidation is generally modest compared to that of other terpenoids. Here we show that isoprene, carbon monoxide and methane can each suppress the instantaneous mass and the overall mass yield derived from monoterpenes in mixtures of atmospheric vapours. We find that isoprene ‘scavenges’ hydroxyl radicals, preventing their reaction with monoterpenes, and the resulting isoprene peroxy radicals scavenge highly oxygenated monoterpene products. These effects reduce the yield of low-volatility products that would otherwise form secondary organic aerosol. Global model calculations indicate that oxidant and product scavenging can operate effectively in the real atmosphere. Thus highly reactive compounds (such as isoprene) that produce a modest amount of aerosol are not necessarily net producers of secondary organic particle mass and their oxidation in mixtures of atmospheric vapours can suppress both particle number and mass of secondary organic aerosol. We suggest that formation mechanisms of secondary organic aerosol in the atmosphere need to be considered more realistically, accounting for mechanistic interactions between the products of oxidizing precursor molecules (as is recognized to be necessary when modelling ozone production).

The potential effect of changing to a nonfossil fuel vehicle fleet was investigated by measuring primary emissions (by extractive sampling of bus plumes) and secondary mass formation, using a Gothenburg Potential Aerosol Mass (Go:PAM) reactor, from 29 in-use transit buses. Regarding fresh emissions, diesel (DSL) buses without a diesel particulate filter (DPF) emitted the highest median mass of particles, whereas compressed natural gas (CNG) buses emitted the lowest (MdEFPM514 and 11 mg kgfuel–1, respectively). Rapeseed methyl ester (RME) buses showed smaller MdEFPMand particle sizes than DSL buses. DSL (no DPF) and hybrid-electric RME (RMEHEV) buses exhibited the highest particle numbers (MdEFPN12 × 1014# kgfuel–1). RMEHEVbuses displayed a significant nucleation mode (Dp< 20 nm). EFPNof CNG buses spanned the highest to lowest values measured. Low MdEFPNand MdEFPMwere observed for a DPF-equipped DSL bus. Secondary particle formation resulting from exhaust aging was generally important for all the buses (79% showed an average EFPM:AGED/EFPM:FRESHratio >10) and fuel types tested, suggesting an important nonfuel dependent source. The results suggest that the potential for forming secondary mass should be considered in future fuel shifts, since the environmental impact is different when only considering the primary emissions.

Few studies have examined behaviors in romantic relationships associated with borderline personality disorder (BPD). We assessed critical variables from marital research: the emotional bank account(positive-to-negative behaviors) and the four horsemen of the apocalypse(criticism, defensiveness, contempt, and stonewalling). Couples (N= 130, or 260 participants) engaged in a conflict task and reported relationship satisfaction at intake and 12 months. Clinician-rated BPD and avoidant PD (APD) criteria were examined. People with more BPD symptoms and their partners were less satisfied, which worsened by follow-up. Conflict behaviors partially explained these associations. Partners of people with more BPD symptoms had a worse emotional bank account, which then predicted (a) poorer satisfaction for both members and (b) worsening partner satisfaction. People with more BPD symptoms criticized more; their partners defended and stonewalled more. APD predicted worsening satisfaction. BPD appears to link specifically with relationship dysfunction, partly through associations with partner behavior.

Shortcomings of approaches to classifying psychopathology based on expert consensus have given rise to contemporary efforts to classify psychopathology quantitatively. In this paper, we review progress in achieving a quantitative and empirical classification of psychopathology. A substantial empirical literature indicates that psychopathology is generally more dimensional than categorical. When the discreteness versus continuity of psychopathology is treated as a research question, as opposed to being decided as a matter of tradition, the evidence clearly supports the hypothesis of continuity. In addition, a related body of literature shows how psychopathology dimensions can be arranged in a hierarchy, ranging from very broad “spectrum level” dimensions, to specific and narrow clusters of symptoms. In this way, a quantitative approach solves the “problem of comorbidity” by explicitly modeling patterns of co‐occurrence among signs and symptoms within a detailed and variegated hierarchy of dimensional concepts with direct clinical utility. Indeed, extensive evidence pertaining to the dimensional and hierarchical structure of psychopathology has led to the formation of the Hierarchical Taxonomy of Psychopathology (HiTOP) Consortium. This is a group of 70 investigators working together to study empirical classification of psychopathology. In this paper, we describe the aims and current foci of the HiTOP Consortium. These aims pertain to continued research on the empirical organization of psychopathology; the connection between personality and psychopathology; the utility of empirically based psychopathology constructs in both research and the clinic; and the development of novel and comprehensive models and corresponding assessment instruments for psychopathology constructs derived from an empirical approach.

•Disadvantageous decisions are a key element of borderline personality.•Pavlovian, habitual, and goal-directed computational systems influence decisions.•Formal models test how these systems are instantiated in behavior and neural activity.•We propose that Pavlovian-to-instrumental transfer (PIT) plays a crucial role in BPD.•Interpersonal dysfunction may reflect the influence of neural circuits involved in PIT.

PurposeThe clinical utility of screening unselected individuals for pathogenic BRCA1/2 variants has not been established. Data on cancer risk management behaviors and diagnoses of BRCA1/2-associated cancers can help inform assessments of clinical utility.MethodsWhole-exome sequences of participants in the MyCode Community Health Initiative were reviewed for pathogenic/likely pathogenic BRCA1/2 variants. Clinically confirmed variants were disclosed to patient–participants and their clinicians. We queried patient–participants’ electronic health records for BRCA1/2-associated cancer diagnoses and risk management that occurred within 12 months after results disclosure, and calculated the percentage of patient–participants of eligible age who had begun risk management.ResultsThirty-seven MyCode patient–participants were unaware of their pathogenic/likely pathogenic BRCA1/2 variant, had not had a BRCA1/2-associated cancer, and had 12 months of follow-up. Of the 33 who were of an age to begin BRCA1/2-associated risk management, 26 (79%) had performed at least one such procedure. Three were diagnosed with an early-stage, BRCA1/2-associated cancer—including a stage 1C fallopian tube cancer—via these procedures.ConclusionScreening for pathogenic BRCA1/2 variants among unselected individuals can lead to occult cancer detection shortly after disclosure. Comprehensive outcomes data generated within our learning healthcare system will aid in determining whether population-wide BRCA1/2 genomic screening programs offer clinical utility.