The COVID-19 pandemic and related restrictions led to major transit demand decline for many public transit systems in the United States. This paper is a systematic analysis of the dynamics and dimensions of this unprecedented decline. Using transit demand data derived from a widely used transit navigation app, we fit logistic functions to model the decline in daily demand and derive key parameters: base value, the apparent minimal level of demand and cliff and base points, representing the initial date when transit demand decline began and the final date when the decline rate attenuated. Regression analyses reveal that communities with higher proportions of essential workers, vulnerable populations (African American, Hispanic, Female, and people over 45 years old), and more coronavirus Google searches tend to maintain higher levels of minimal demand during COVID-19. Approximately half of the agencies experienced their decline before the local spread of COVID-19 likely began; most of these are in the US Midwest. Almost no transit systems finished their decline periods before local community spread. We also compare hourly demand profiles for each system before and during COVID-19 using ordinary Procrustes distance analysis. The results show substantial departures from typical weekday hourly demand profiles. Our results provide insights into public transit as an essential service during a pandemic.

Background: The COVID-19 outbreak has brought tremendous psychological pressure to the general population, which may lead to depression. Therefore, this study aim to evaluate the prevalence and clinical correlates of depressive symptoms in the general population quarantined during the COVID-19 outbreak in Shenzhen. Methods: 2237 quarantined general individuals participated in this cross-sectional study from February 14 to March 4, 2020, during their 14 days quarantine. They completed the Zung's Self-Rating Depression Scale (SDS) for depression, Zung's self-rating anxiety scale (SAS) for anxiety, the Pittsburgh Sleep Quality Index (PSQI) for sleep quality, and the Impact of Events Scale-Revised (IES-R) for post-traumatic stress symptoms (PTSS). Results: The prevalence of depressive symptom was 6.21% in quarantined individuals. The depressed group were younger, less married and educated, and had higher SAS, PSQI, IES-R total scores (all p<0.05), as well as more avoidance, intrusion and hyperarousal symptoms than the non-depressed group. Correlation analysis showed significant correlations between SDS score and the following parameters: age, marriage, education, SAS, PSQI, IES-R total and its three subscale scores (Bonferroni corrected all p<0.05). Further multiple regression indicated that age, marriage, education, SAS, PSQI, IES-R total score, Avoidance and Hyperarousal factor were independent predictors of depressive symptom. Limitations: This study adopted a cross-sectional design and used self-report questionnaires. Conclusions: Our results suggest an elevated prevalence of depressive symptom in quarantined general individuals in Shenzhen. Some demographic and clinical variables were associated with depressive symptoms.

BackgroundCognitive impairments are prominent in schizophrenia (SZ). Imaging studies have demonstrated that functional changes of several areas of the brain exist in SZ patients. The relationships between these two indexes are largely unexplored in SZ. The MATRICS Consensus Cognitive Battery (MCCB) was used to measure cognitive impairment in multi-dimensional cognitive fields of SZ patients. This study was conducted to explore the relationship between cognitive functional impairment and the amplitude of low-frequency fluctuation (ALFF) in SZ patients.MethodA total of 104 participants (44 SZ patients and 60 age- and gender-matched healthy controls (HC)) were recruited for this study. The MCCB was used to assess cognitive function of the participants, while brain activity was assessed using the ALFF. The relationship between the MCCB and the ALFF was investigated by using a correlation analysis.ResultsThere were significant differences between SZ patients and HC in MCCB total and domain scores as well as in ALFF results. The reduction of ALFF in the bilateral postcentral gyri and paracentral lobule in SZ patients has a negative correlation with the MCCB sub-test of symbol coding.ConclusionThese findings suggest that the reduction of ALFF in bilateral postcentral gyri and paracentral lobule may be related to cognitive impairment in SZ patients.Electronic supplementary materialThe online version of this article (10.1186/s12888-018-1992-4) contains supplementary material, which is available to authorized users.

Phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] is an important cofactor for ion channels. Affinity for this lipid is a major determinant of channel inhibition by depletion of PI(4,5)P2 upon phospholipase C (PLC) activation. Little is known about what determines PI(4,5)P2 affinity in mammalian ion channels. Here we report that two members of the Transient Receptor Potential Vanilloid (TRPV) ion channel family, TRPV5 and TRPV6 lack a positively charged residue in the TM4-TM5 loop that was shown to interact with PI(4,5)P2 in TRPV1, which shows high affinity for this lipid. When this positively charged residue was introduced to either TRPV6 or TRPV5, they displayed markedly higher affinities for PI(4,5)P2, and were largely resistant to inhibition by PI(4,5)P2 depletion. Furthermore, Ca2+-induced inactivation of TRPV6 was essentially eliminated in the G488R mutant, showing the importance of PLC-mediated PI(4,5)P2 depletion in this process. Computational modeling shows that the introduced positive charge interacts with PI(4,5)P2 in TRPV6.

The cold-and menthol-sensitive transient receptor potential melastatin 8 (TRPM8) channel is important for both physiological temperature detection and cold allodynia. Activation of G-protein-coupled receptors (GPCRs) by proinflammatory mediators inhibits these channels. It was proposed that this inhibition proceeds via direct binding of G ␣q to the channel. TRPM8 requires the plasma membrane phospholipid phosphatidylinositol 4,5-bisphosphate [PI(4,5)P 2 or PIP 2 ] for activity. However, it was claimed that a decrease in cellular levels of this lipid upon receptor activation does not contribute to channel inhibition. Here, we show that supplementing the whole-cell patch pipette with PI(4,5)P 2 reduced inhibition of TRPM8 by activation of G ␣q -coupled receptors in mouse dorsal root ganglion (DRG) neurons isolated from both sexes. Stimulating the same receptors activated phospholipase C (PLC) and decreased plasma membrane PI(4,5)P 2 levels in these neurons. PI(4,5)P 2 also reduced inhibition of TRPM8 by activation of heterologously expressed muscarinic M1 receptors. Coexpression of a constitutively active G ␣q protein that does not couple to PLC inhibited TRPM8 activity, and in cells expressing this protein, decreasing PI(4,5)P 2 levels using a voltage-sensitive 5Ј-phosphatase induced a stronger inhibition of TRPM8 activity than in control cells. Our data indicate that, upon GPCR activation, G ␣q binding reduces the apparent affinity of TRPM8 for PI(4,5)P 2 and thus sensitizes the channel to inhibition induced by decreasing PI(4,5)P 2 levels.Increased sensitivity to heat in inflammation is partially mediated by inhibition of the cold-and menthol-sensitive transient receptor potential melastatin 8 (TRPM8) ion channels. Most inflammatory mediators act via G-protein-coupled receptors that activate the phospholipase C pathway, leading to the hydrolysis of phosphatidylinositol 4,5-bisphosphate [PI(4,5)P 2 ]. How receptor activation by inflammatory mediators leads to TRPM8 inhibition is not well understood. Here, we propose that direct binding of G ␣q both reduces TRPM8 activityandsensitizesthechanneltoinhibitionbydecreasedlevelsofitscofactor,PI(4,5)P 2 .Ourdatademonstratetheconvergenceoftwo downstream effectors of receptor activation, G ␣q and PI(4,5)P 2 hydrolysis, in the regulation of TRPM8.