The COVID-19 pandemic impacted maternal mental health differently depending on pregnancy status and trimester of gestation

Introduction: We aimed to measure the impact of the COVID-19 pandemic on maternal mental health, stratifying on pregnancy status, trimester of gestation, and pandemic period/wave.Methods: Pregnant persons and persons who delivered in Canada during the pandemic, >18 years, were recruited, and data were collected using a web-based strategy. The current analysis includes data on persons enrolled between 06/2020-08/2021. Maternal sociodemographic indicators, mental health measures (Edinburgh Perinatal Depression Scale (EPDS), Generalized Anxiety Disorders (GAD-7), stress) were self-reported. Maternal mental health in pregnant women (stratified by trimester, and pandemic period/wave at recruitment) was compared with mental health of women who had delivered; determinants of severe depression were identified with multivariate logistic regression models.Results: 2,574 persons were pregnant and 626 had already delivered at recruitment. Participants who had delivered had significantly higher mean depressive symptom scores compared to those pregnant at recruitment (9.1 (SD, 5.7) vs. 8.4 (SD, 5.3), p=0.009). Among those who were pregnant at recruitment, depressive symptoms were significantly higher in women recruited in their third trimester, and those recruited during the 2nd wave of the pandemic. Maternal anxiety (aOR 1.51; 95%CI 1.44-1.59) and stress (aOR 1.35; 95%CI 1.24-1.48) were the most significant predictors of severe maternal depression (EDPS˃13) in pregnancy. Conclusion: The COVID-19 pandemic had a significant impact on maternal depression during pregnancy and in the post-partum period. Given that gestational depression/anxiety/stress have been associated with preterm birth and childhood cognitive problems, it is essential to continue following women/children, and develop strategies to reduce COVID-19’s longer-term impact.

Hidrodinamika Gelombang pada Terumbu Karang di Pulau Panjang, Jepara

Posisi Pulau Panjang berada di sisi barat garis pantai pesisir kota Jepara, menjadikannya sebagai penghalang (barrier) terhadap gelombang yang akan menghantam pesisir Jepara. Pulau Panjang dikelilingi oleh gugusan terumbu karang. Keterpaparan (exposure) terumbu karang oleh hidrodinamika gelombang yang melewatinya perlu dikaji. Oleh sebab itu, dibutuhkan penelitian mengenai hidrodinamika gelombang pada terumbu karang di perairan Pulau Panjang. Hasil penelitian didapatkan bahwa nilai gelombang yaitu gelombang signifikan (Hs), periode gelombang signifikan (Ts) adalah bervariasi. Nilai gelombang (Hs dan Hs) tinggi, akan mengakibatkan terumbu karang pada sisi barat, timur laut dan tenggara Pulau Panjang lebih menerima keterpaparan (ekposure) oleh hidrodinamika gelombang yang melewatinya. Pada hidrodinamika gelombang lebih rendah, maka terumbu karang yang terlindung dari keterpaparan (ekposure) gelombang adalah yang berada pada sisi timur, barat daya, dan barat laut. Hasil interpolasi (Krigging) didapatkan hasil nilai Hs tertinggi berkisar antara 0,503-1,00. Arah datang gelombang dominan dari timur pulau Panjang, kemudian setelah melewati terumbu karang ada di sisi timur ,timur laut, dan utara Pulau Panjang maka energinya menjadi berkurang, sehingga terumbu karang yang ada di sisi barat, barat daya, dan selatan dari Pulau Panjang posisinya lebih aman dari keterpaparan (ekposure) oleh hidrodinamika gelombang yang melewatinya. Gelombang yang datang akan mengalami perubahan karakteristik (panjang, periode, tinggi gelombang) setelah melewati terumbu karang, sehingga gelombang yang menuju pantai akan semakin berkurang seiring dengan perubahan kedalaman. Tingkat keterpaparan (ekposure) terumbu karang yang ada pada sisi timur,timur laut dan utara di Pulau Panjang oleh gelombang cukup tinggi, hal ini diduga yang menjadi salah satu faktor penyebab kerusakan terumbu karang yang ada diperairan Pulau Panjang. The position of Pulau Panjang is on the west side of the coastal coastline of the city of Jepara, making it a barrier against waves that will hit the coast of Jepara. Panjang Island is surrounded by clusters of coral reefs. The exposure (exposure) of coral reefs by the hydrodynamics of the waves that pass through them needs to be studied. The modeling results are then generated into a shapefile map to be overlaid with a shapefile map of changes in coral reefs by interpolation method with Kriging block. The results showed that the wave value, namely the significant wave (Hs), the period of the significant wave (Ts) varied. High wave values (Hs and Hs) will result in coral reefs on the west, northeast, and southeast sides of Panjang Island receiving more exposure (exposure) by the hydrodynamics of the waves that pass through them. At lower wave hydrodynamics, the coral reefs that are protected from wave exposure are those on the east, southwest, and northwest sides. The results of interpolation (Kriging) obtained the highest Hs values ranging from 0.503 to 1.00. The direction of the dominant wave coming from the east of Panjang Island, then after passing through the coral reefs is on the east, northeast, and north of Panjang Island, the energy is reduced, so that the coral reefs on the west, southwest, and south sides of Panjang Island are safer from exposure (exposure) by the hydrodynamics of waves that pass through it. The incoming waves will experience changes in characteristics (length, period, wave height) after passing through the coral reef so that the waves towards the coast will decrease along with changes in depth. The level of exposure to coral reefs on the east, northeast, and north sides of Panjang Island by waves is quite high, this is thought to be one of the factors causing damage to coral reefs in the waters of Panjang Island.

Evaluation of anchorage performance of the switchboard cabinet under seismic loading condition

In this study, the seismic response of the anchorage used for switchboard cabinets at a power plant was presented based on the results of an experiment and numerical simulations. In the experimental study, shaking table tests were performed to investigate the overall structural behavior of switchboard cabinets. The finite element modeling was conducted using the ABAQUS program, and in order to validate the proposed finite element model, the natural frequency, stress, and displacement were compared with the experimental results. A slight difference was found in the results due to the problem cup-like deformation at the anchorage of the bottom, but it showed reasonable agreement when considering the results for all behaviors. Using the proven model, nonlinear dynamic analysis was performed using three types of a period waves. The maximum stress on the anchorage occurred when a long-period wave was applied, and the horizontal maximum displacement of the cabinet was approximately 10 times greater than when an ultra-short-period wave was applied. It is expected that the flexibility of the cabinet stiffness resulted in more structural weakness, especially under a long-period wave, and that is recommended to focus on displacement rather than stress when establishing seismic design guidelines for switchboard cabinets.

The Unusual Intensity Pattern of OH(6,2) and O(1S) Airglow Observed Over the Andes Lidar Observatory

<p>Simultaneous observations of OH(6,2) and O(<sup>1</sup>S) nightglow at the Andes Lidar Observatory (ALO) from September 2011 to April 2018 have been analyzed to investigate an unusual intensity pattern showing an O(<sup>1</sup>S) nightglow intensity enhancement concurrent with an OH(6,2) nightglow intensity weakening. About 142 nights have been identified in the time period showing a remarkable biannual occurrence rate with maxima during the equinoxes. A semidiurnal (12-h) tide fitting applied to the 30-min bin size monthly averaged data shows that the largest amplitudes of the semidiurnal tide were observed for the months of April and August-October in the OH(6,2) data and April and September in the O(<sup>1</sup>S) data. It was also found that SABER’s atomic oxygen at the O(<sup>1</sup>S) peak height is 1.3-2.5 times higher during the nights that displayed the unusual intensity pattern. Simulations using the nonlinear, time-dependent, OH Chemistry Dynamics (OHCD) and Multiple Airglow Chemistry Dynamics (MACD) models have also been used to investigate the effect of a long-period wave on the OH(6,2) and O(<sup>1</sup>S) airglow intensities. The simulation results are in good agreement with the observations and replicate the unusual intensity pattern observed in the OH(6,2) and O(<sup>1</sup>S) airglow data.</p>

Wolf Rock lighthouse: past developments and future survivability under wave loading

Lighthouses situated on exposed rocky outcrops warn mariners of the dangers that lurk beneath the waves. They were first constructed when approaches to wave loading and structural response were relatively unsophisticated, essentially learning from previous failures. Here, we chart the evolution of lighthouses on the Wolf Rock, situated between Land's End and the Isles of Scilly in the UK. The first empirical approaches are described, followed by design aspects of the present tower, informed by innovations developed on other rocky outcrops. We focus on a particular development associated with the automation of lighthouses: the helideck platform. The design concept is described and the structure then scrutinized for future survivability, using the latest structural modelling techniques of the entire lighthouse and helideck. Model validation data were obtained through a complex logistical field operation and experimental modal analysis. Extreme wave loading for the model required the identification of the 250-year return period wave using a Bayesian method with informative prior distributions, for two different scenarios (2017 and 2067). The structural models predict responses of the helideck to wave loading which is characterized by differential displacements of 0.093 m (2017) and 0.115 m (2067) with associated high tension forces and plastic strain. This article is part of the theme issue ‘Environmental loading of heritage structures’.

The Impact of Modelling Air Compressibility in the Selection of Optimal OWC Design Parameters in Site Specific Wave Conditions

The importance of properly modelling the effects of air compressibility in the selection of the optimal design parameters for an Oscillating Water Column wave energy converter is investigated. For this purpose, a wide dataset of capture width ratios, obtained from both experimental tests and Computational Fluid Dynamic simulations, is used to formulate an empirical model able to predict the performance of the device as a function of its basic design parameters (chamber width and draught, turbine damping) and of the wave conditions (wave period, wave height). A multiple non-linear regression approach is used to determine the model numerical coefficients. The data used to formulate the model include the effects of air compressibility. The impact of considering such effects on the selection of the optimal geometry of the device is evaluated and discussed by means of the model application for the optimization of a device to be installed in a site located in the Mediterranean Sea (in front of the coast of Tuscany, Italy).

Wave Force Characteristics of Large-Sized Offshore Wind Support Structures to Sea Levels and Wave Conditions

This paper presents the results of wave force tests conducted on three types of offshore support structures considering eight waves and three sea levels to investigate the corresponding wave forces. As a result of this study, it is found that the occurrence of shoaling in shallow water induces a significant increase of the wave force. Most of the test models at the shallow water undergo a nonlinear increase of the wave force with higher wave height increasing. In addition, the larger the diameter of the support structure within the range of this study, the larger the diffraction effect is, and the increase in wave force due to shoaling is suppressed. Under an irregular wave at the shallow water, the wave force to the long-period wave tends to be slightly higher than that of the short period wave since the higher wave height component included in the irregular wave has an influence on the shoaling. In addition, it is found that the influence of shoaling under irregular wave becomes more apparent in the long period.