Noise power spectrum (NPS) in computed tomography: Enabling local NPS measurement without stationarity and ergodicity assumptions.

BACKGROUND: Conventional methods for estimating the noise power spectrum (NPS) often necessitate multiple computed tomography (CT) data acquisitions and are required to satisfy stringent stationarity and ergodicity conditions, which prove challenging in CT imaging systems. PURPOSE: The aim was to revisit the conventional NPS estimation method, leading to a new framework that estimates local NPS without relying on stationarity or ergodicity, thus facilitating experimental NPS estimations. METHODS: The scientific foundation of the conventional CT NPS measurement method, based on the Wiener-Khintchine theorem, was reexamined, emphasizing the critical conditions of stationarity and ergodicity. This work proposes an alternative framework, characterized by its independence from stationarity and ergodicity, and its ability to facilitate local NPS estimations. A spatial average of local NPS over a Region of Interest (ROI) yields the conventional NPS for that ROI. The connections and differences between the proposed alternative method and the conventional method are discussed. Experimental studies were conducted to validate the new method. RESULTS: (1) The NPS estimated using the conventional method was demonstrated to correspond to the spatial average of pointwise NPS from the proposed NPS estimation framework. (2) The NPS estimated over an ROI with the conventional method was shown to be the sum of the NPS estimated from the proposed method and a contribution from measurement uncertainty. (3) Local NPS estimations from the proposed method in this work elucidate the impact of surrounding image content on local NPS variations. CONCLUSION: The NPS estimation method proposed in this work allows for the estimation of local NPS without relying on stationarity and ergodicity conditions, offering local NPS estimations with significantly improved precision.

Outcomes and Complications of Sole Reconstruction Using Lateral Thoracic Free Tissue Transfer.

BACKGROUND: The complex structure of the sole of the foot makes the repair of extensive defects challenging. The present study, therefore, aimed to address a gap in current research by evaluating the potential of the lateral thoracic free flap, including perforator options and chimeric configurations, to be used as an advanced solution for comprehensive sole reconstruction. PATIENTS AND METHODS: We retrospectively collected the following data from the charts of patients with sole defects, due to various causes, who underwent lateral thoracic free tissue transfers: patient demographics; etiologies; comorbidities; flap types and dimensions; pedicle length; operative time; follow-up period; complications; and management. RESULTS: The present study included 54 patients who underwent lateral thoracic free tissue transfer, citing infection, trauma, tumor, and posttraumatic sequelae as the major etiologies. We used the following techniques for the reconstruction of sole defects: thoracodorsal artery perforator free flap (83.3%); latissimus dorsi musculocutaneous free flap (1.9%); and various chimeric pattern flaps (14.8%). Free tissue transfer in the lateral thoracic region offers versatility for reconstruction, as well as low donor site morbidity. Complications observed in the present study included wound dehiscence (9.3%), partial necrosis (9.3%), and pressure ulcers (22.2%), although most patients healed favorably without flap loss. CONCLUSIONS: The lateral thoracic free flap is a viable option for the reconstruction of the sole of the foot and allows for the effective reconstruction of complex defects. It contains a sustainable skin paddle, and multiple components can be easily included as a chimeric type. Further studies should seek to identify ways to prevent pressure ulcers, which was the only known long-term complication in the present study.

The spatiotemporal evolution of rural landscape patterns in Chinese metropolises under rapid urbanization.

Understanding the evolution of rural landscapes in metropolises during rapid urbanization is crucial for formulating policies to protect the rural ecological environment. In this study, remote sensing and geographical information system data, as well as applied landscape index analysis, are used to examine the spatiotemporal evolution of rural landscape patterns in the Beijing-Tianjin region of China, which has experienced rapid urbanization. The relationships between land use/land cover changes and changes in rural landscape patterns are explored. The results revealed significant spatial differences in the rural landscapes in the Beijing-Tianjin region; farmland and forestland were the main types of landscapes, creating a "mountain-field-sea" natural landscape pattern. The conversion of rural landscapes in the Beijing-Tianjin region involved mainly the conversion of farmland to urban areas, with few exchanges between other landscape types. The urban areas in the Beijing-Tianjin region increased by 3% per decade; farmland decreased at the same rate. Additionally, the rural landscape patterns in the Beijing-Tianjin region were dominated by fragmentation, dispersion, and heterogeneity and moved from complex to regular. Water bodies displayed the most fragmented natural landscape; their number of patches increased by 36%, though their network characteristics were maintained. Forestland was the most concentrated natural landscape. In this study, theoretical support and a scientific reference for the optimization of rural landscape patterns and the improvement in rural living environments in rapidly urbanizing areas are provided.

Improving stroke prognosis by TLR4 KO to enhance N2 neutrophil infiltration and reduce M1 macrophage polarization.

Cerebral ischemic stroke remains a leading cause of mortality and morbidity worldwide. Toll-like receptor 4 (TLR4) has been implicated in neuroinflammatory responses poststroke, particularly in the infiltration of immune cells and polarization of macrophages. This study aimed to elucidate the impact of TLR4 deficiency on neutrophil infiltration and subsequent macrophage polarization after middle cerebral artery occlusion (MCAO), exploring its role in stroke prognosis. The objective was to investigate how TLR4 deficiency influences neutrophil behavior poststroke, its role in macrophage polarization, and its impact on stroke prognosis using murine models. Wild-type and TLR4-deficient adult male mice underwent MCAO induction, followed by various analyses, including flow cytometry to assess immune cell populations, bone marrow transplantation experiments to evaluate TLR4-deficient neutrophil behaviors, and enzyme-linked immunosorbent assay and Western blot analysis for cytokine and protein expression profiling. Neurobehavioral tests and infarct volume analysis were performed to assess the functional and anatomical prognosis poststroke. TLR4-deficient mice exhibited reduced infarct volumes, increased neutrophil infiltration, and reduced M1-type macrophage polarization post-MCAO compared to wild-type mice. Moreover, the depletion of neutrophils reversed the neuroprotective effects observed in TLR4-deficient mice, suggesting the involvement of neutrophils in mediating TLR4's protective role. Additionally, N1-type neutrophils were found to promote M1 macrophage polarization via neutrophil gelatinase-associated lipocalin (NGAL) secretion, a process blocked by TLR4 deficiency. The study underscores the protective role of TLR4 deficiency in ischemic stroke, delineating its association with increased N2-type neutrophil infiltration, diminished M1 macrophage polarization, and reduced neuroinflammatory responses. Understanding the interplay between TLR4, neutrophils, and macrophages sheds light on potential therapeutic targets for stroke management, highlighting TLR4 as a promising avenue for intervention in stroke-associated neuroinflammation and tissue damage.

Chirality Transfer of Glycopeptide across Scales Defined by the Continuity of Hydrogen Bonds.

In nature, chirality transfer refines biomolecules across all size scales, bestowing them with a myriad of sophisticated functions. Despite recent advances in replicating chirality transfer with biotic or abiotic building blocks, a molecular understanding of the underlying mechanism of chirality transfer remains a daunting challenge. In this paper, the coassembly of two types of glycopeptide molecules differing in capability of forming intermolecular hydrogen bonds enabled the involvement of discontinuous hydrogen bond, which allowed for a nanoscale chirality transfer from glycopeptide molecules to chiral micelles, yet inhibited the micrometer scale chirality transfer toward helix formation, leading to an achiral transfer from chiral micelles to planar monolayer. Upon stacking the monolayer into a bilayer, the nonsuperimposable front and back faces of the chiral micelles involved in the monolayer ribbons lead to the opposite rotation of two layers toward increasing the continuity of H-bonds. The resultant continuity triggered the symmetry breaking of stacked bilayers and thus reactivated the micrometer-scale chirality transfer toward the final helix. This work delineates a promising step toward a better understanding and replicating the naturally occurring chirality transfer events and will be instructive to future chiral material design.

Protocol for mass spectrometric profiling of lysine malonylation by lysine acetyltransferase in CRISPRi K562 cell lines.

Lysine malonylation is a protein posttranslational modification. We present a protocol to generate stable gene-knockdown K562 cell lines through lentiviral infection of a CRISPR interference (CRISPRi) system followed by lysine malonylation measurement using mass spectrometry (MS). We detail guide RNA (gRNA) vector cloning, lentiviral infection, cell line purification, protein digestion, malonyl-lysine enrichment, desalting, and MS acquisition and analysis. For complete details on the use and execution of this protocol, please refer to Zhang et al.1 and Bons et al.2.

Utilization of carbon catabolite repression for efficiently biotransformation of anthraquinone O-glucuronides by Streptomyces coeruleorubidus DM.

Carbon catabolite repression (CCR) is a highly conserved mechanism that regulates carbon source utilization in Streptomyces. CCR has a negative impact on secondary metabolite fermentation, both in industrial and research settings. In this study, CCR was observed in the daunorubicin (DNR)-producing strain Streptomyces coeruleorubidus DM, which was cultivated in high concentration of carbohydrates. Unexpectedly, DM exhibited a high ability for anthraquinone glucuronidation biotransformation under CCR conditions with a maximum bioconversion rate of 95% achieved at pH 6, 30°C for 24 h. The co-utilization of glucose and sucrose resulted in the highest biotransformation rate compared to other carbon source combinations. Three novel anthraquinone glucuronides were obtained, with purpurin-O-glucuronide showing significantly improved water solubility, antioxidant activity, and antibacterial bioactivity. Comparative transcript analysis revealed that glucose and sucrose utilization were significantly upregulated as DM cultivated under CCR condition, which strongly enhance the biosynthetic pathway of the precursors Uridine diphosphate glucuronic acid (UDPGA). Meanwhile, the carbon metabolic flux has significantly enhanced the fatty acid biosynthesis, the exhaust of acetyl coenzyme A may lead to the complete repression of the biosynthesis of DNR, Additionally, the efflux transporter genes were simultaneously downregulated, which may contribute to the anthraquinones intracellular glucuronidation. Overall, our findings demonstrate that utilizing CCR can be a valuable strategy for enhancing the biotransformation efficiency of anthraquinone O-glucuronides by DM. This approach has the potential to improve the bioavailability and therapeutic potential of these compounds, opening up new possibilities for their pharmaceutical applications.

Application of Deferoxamine in Tissue Regeneration Attributed to Promoted Angiogenesis.

Deferoxamine, an iron chelator used to treat diseases caused by excess iron, has had a Food and Drug Administration-approved status for many years. A large number of studies have confirmed that deferoxamine can reduce inflammatory response and promote angiogenesis. Blood vessels play a crucial role in sustaining vital life by facilitating the delivery of immune cells, oxygen, and nutrients, as well as eliminating waste products generated during cellular metabolism. Dysfunction in blood vessels may contribute significantly to the development of life-threatening diseases. Anti-angiogenesis therapy and pro-angiogenesis/angiogenesis strategies have been frequently recommended for various diseases. Herein, we describe the mechanism by which deferoxamine promotes angiogenesis and summarize its application in chronic wounds, bone repair, and diseases of the respiratory system. Furthermore, we discuss the drug delivery system of deferoxamine for treating various diseases, providing constructive ideas and inspiration for the development of new treatment strategies.

Carbon-nitrogen transmutation in polycyclic arenol skeletons to access N-heteroarenes.

Developing skeletal editing tools is not a trivial task, and realizing the corresponding single-atom transmutation in a ring system without altering the ring size is even more challenging. Here, we introduce a skeletal editing strategy that enables polycyclic arenols, a highly prevalent motif in bioactive molecules, to be readily converted into N-heteroarenes through carbon-nitrogen transmutation. The reaction features selective nitrogen insertion into the C-C bond of the arenol frameworks by azidative dearomatization and aryl migration, followed by ring-opening, and ring-closing (ANRORC) to achieve carbon-to-nitrogen transmutation in the aromatic framework of the arenol. Using widely available arenols as N-heteroarene precursors, this alternative approach allows the streamlined assembly of complex polycyclic heteroaromatics with broad functional group tolerance. Finally, pertinent transformations of the products, including synthesis complex biheteroarene skeletons, were conducted and exhibited significant potential in materials chemistry.

Experimental measurement of local noise power spectrum (NPS) in photon counting detector-CT (PCD-CT) using a single data acquisition.

BACKGROUND: Accurate noise power spectra (NPS) measurement in clinical X-ray CT exams is challenging due to the need for repeated scans, which expose patients to high radiation risks. A reliable method for single CT acquisition NPS estimation is thus highly desirable. PURPOSE: To develop a method for estimating local NPS from a single photon counting detector-CT (PCD-CT) acquisition. METHODS: A novel nearly statistical bias-free estimator was constructed from the raw counts data of PCD-CT scan to estimate the variance of sinogram projection data. An analytical algorithm is employed to reconstruct point-wise covariance cov ( x i , x j ) $\text{cov}({\bf x}_i,{\bf x}_j)$ between any two image pixel/voxel locations x i ${\bf x}_i$ and x j ${\bf x_j}$ . A Fourier transform is applied to obtain the desired point-wise NPS for any chosen location x i ${\bf x}_i$ . The method was validated using experimental data acquired from a benchtop PCD-CT system with various physical phantoms, and the results were compared with the conventional local NPS measurement method using repeated scans and statistical ensemble averaging. RESULTS: The experimental results demonstrate that (1) the proposed method can achieve pointwise/local NPS measurement for a region of interest (ROI) located at any chosen position, accurately characterizing the NPS with spatial structures resulting from image content heterogeneity; (2) the local NPS measured using the proposed method show a higher precision in the measured NPS compared to the conventional measurement method; (3) spatial averaging of the local NPS yields the conventional NPS for a given local ROI. CONCLUSION: A new method was developed to enable local NPS from a single PCD-CT acquisition.

In vivo rescue of genetic dilated cardiomyopathy by systemic delivery of nexilin.

BACKGROUND: Dilated cardiomyopathy (DCM) is one of the most common causes of heart failure. Multiple identified mutations in nexilin (NEXN) have been suggested to be linked with severe DCM. However, the exact association between multiple mutations of Nexn and DCM remains unclear. Moreover, it is critical for the development of precise and effective therapeutics in treatments of DCM. RESULTS: In our study, Nexn global knockout mice and mice carrying human equivalent G645del mutation are studied using functional gene rescue assays. AAV-mediated gene delivery is conducted through systemic intravenous injections at the neonatal stage. Heart tissues are analyzed by immunoblots, and functions are assessed by echocardiography. Here, we identify functional components of Nexilin and demonstrate that exogenous introduction could rescue the cardiac function and extend the lifespan of Nexn knockout mouse models. Similar therapeutic effects are also obtained in G645del mice, providing a promising intervention for future clinical therapeutics. CONCLUSIONS: In summary, we demonstrated that a single injection of AAV-Nexn was capable to restore the functions of cardiomyocytes and extended the lifespan of Nexn knockout and G645del mice. Our study represented a long-term gene replacement therapy for DCM that potentially covers all forms of loss-of-function mutations in NEXN.

Delta opioid peptide [D-ala2, D-leu5]-Enkephalin's ability to enhance mitophagy via TRPV4 to relieve ischemia/reperfusion injury in brain microvascular endothelial cells.

BACKGROUND: Local brain tissue can suffer from ischaemia/reperfusion (I/R) injury, which lead to vascular endothelial damage. The peptide δ opioid receptor (δOR) agonist [D-ala2, D-leu5]-Enkephalin (DADLE) can reduce apoptosis caused by acute I/R injury in brain microvascular endothelial cells (BMECs). OBJECTIVE: This study aims to explore the mechanism by which DADLE enhances the level of mitophagy in BMECs by upregulating the expression of transient receptor potential vanilloid subtype 4 (TRPV4). METHODS: BMECs were extracted and made to undergo oxygen-glucose deprivation/reoxygenation (OGD/R) accompanied by DADLE. RNA-seq analysis revealed that DADLE induced increased TRPV4 expression. The CCK-8 method was used to assess the cellular viability; quantitative PCR (qPCR) was used to determine the mRNA expression of Drp1; western blot was used to determine the expression of TRPV4 and autophagy-related proteins; and calcium imaging was used to detect the calcium influx. Autophagosomes in in the cells' mitochondria were observed by using transmission electron microscopy. ELISA was used to measure ATP content, and a JC-1 fluorescent probe was used to detect mitochondrial membrane potential. RESULTS: When compared with the OGD/R group, OGD/R+DADLE group showed significantly enhanced cellular viability; increased expression of TRPV4, Beclin-1, LC3-II/I, PINK1 and Parkin; decreased p62 expression; a marked rise in calcium influx; further increases in mitophagy, an increase in ATP synthesis and an elevation of mitochondrial membrane potential. These protective effects of DADLE can be blocked by a TRPV4 inhibitor HC067047 or RNAi of TRPV4. CONCLUSION: DADLE can promote mitophagy in BMECs through TRPV4, improving mitochondrial function and relieving I/R injury.

Neuroplasticity of visual brain network induced by hypoxia.

The effects of hypoxia on brain function remain largely unknown. This study aimed to clarify this issue by visual-stimulated functional magnetic resonance imaging design. Twenty-three college students with a 30-d high-altitude exposure were tested before, 1 week and 3 months after returning to sea level. Brain functional magnetic resonance imaging and retinal electroretinogram were acquired. One week after returning to sea level, decreased blood oxygenation level dependent in the right lingual gyrus accompanied with increased blood oxygenation level dependent in the frontal cortex and insular cortex, and decreased amplitude of electroretinogram a-wave in right eye; moreover, the bilateral lingual gyri showed increased functional connectivity within the dorsal visual stream pathway, and the blood oxygenation level dependent signals in the right lingual gyrus showed positive correlation with right retinal electroretinogram a-wave. Three months after returning to sea level, the blood oxygenation level dependent signals recovered to normal level, while intensively increased blood oxygenation level dependent signals in a broad of brain regions and decreased retinal electroretinogram were also existed. In conclusion, hypoxic exposure has long-term effects on visual cortex, and the impaired retinal electroretinogram may contribute to it. The increased functional connectivity of dorsal stream may compensate for the decreased function of retinal photoreceptor cells to maintain normal visual function.

Corrigendum: Insulin resistance and dyslipidemia in low-birth-weight goat kids.

[This corrects the article DOI: 10.3389/fvets.2024.1370640.].

Incidence of postoperative venous thromboembolism in patients with vulvar carcinoma undergoing vulvectomy with or without lymphadenectomy.

OBJECTIVES: The incidence of venous thromboembolism (VTE) following radical surgery for vulvar carcinoma remains poorly characterized, and recommendations for postoperative chemoprophylaxis are varied. Our objective was to assess the incidence of postoperative VTE in patients undergoing surgery for vulvar carcinoma and to determine if VTE incidence differs by radical vulvectomy with or without lymph node assessment. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was queried for patients with a diagnosis of vulvar cancer undergoing radical vulvectomy with or without lymph node assessment from 2012 to 2020. Clinical characteristics and 30-day incidence of VTE as well as other postoperative outcomes were abstracted. Variables were compared using Chi-square test and Fischer's exact test, as well as Kruskal-Wallis and Wilcoxon rank sum tests where appropriate. RESULTS: A total of 1672 patients underwent radical vulvectomy for vulvar carcinoma. 11 patients (0.7%) experienced postoperative VTE within 30 days of surgery. The incidence of VTE was similar when radical vulvectomy was performed alone or with lymph node dissection by any method (p = 0.116). Longer operative times (p = 0.033) and greater postoperative length of stay (p = 0.001) were associated with increased risk of postoperative VTE. CONCLUSIONS: The incidence of postoperative VTE is low in patients undergoing radical vulvar surgery in this national cohort. Inguinofemoral lymph node dissection by any method does not appear to be a risk factor for VTE when compared to radical vulvectomy alone. Further research is needed to determine if extended VTE prophylaxis is beneficial in this population.

Identification of seven variants in the col4a1 gene that alter RNA splicing by minigene assay.

Type IV collagen is an integral component of basement membranes. Mutations in COL4A1, one of the key genes encoding Type IV collagen, can result in a variety of diseases. It is clear that a significant proportion of mutations that affect splicing can cause disease directly or contribute to the susceptibility or severity of disease. Here, we analyzed exonic mutations and intronic mutations described in the COL4A1 gene using bioinformatics programs and identified candidate mutations that may alter the normal splicing pattern through a minigene system. We identified seven variants that induce splicing alterations by disrupting normal splice sites, creating new ones, or altering splice regulatory elements. These mutations are predicted to impact protein function. Our results help in the correct molecular characterization of variants in COL4A1 and may help develop more personalized treatment options.

Digital Dietary Behaviors in Individuals With Depression: Real-World Behavioral Observation.

BACKGROUND: Depression is often accompanied by changes in behavior, including dietary behaviors. The relationship between dietary behaviors and depression has been widely studied, yet previous research has relied on self-reported data which is subject to recall bias. Electronic device-based behavioral monitoring offers the potential for objective, real-time data collection of a large amount of continuous, long-term behavior data in naturalistic settings. OBJECTIVE: The study aims to characterize digital dietary behaviors in depression, and to determine whether these behaviors could be used to detect depression. METHODS: A total of 3310 students (2222 healthy controls [HCs], 916 with mild depression, and 172 with moderate-severe depression) were recruited for the study of their dietary behaviors via electronic records over a 1-month period, and depression severity was assessed in the middle of the month. The differences in dietary behaviors across the HCs, mild depression, and moderate-severe depression were determined by ANCOVA (analyses of covariance) with age, gender, BMI, and educational level as covariates. Multivariate logistic regression analyses were used to examine the association between dietary behaviors and depression severity. Support vector machine analysis was used to determine whether changes in dietary behaviors could detect mild and moderate-severe depression. RESULTS: The study found that individuals with moderate-severe depression had more irregular eating patterns, more fluctuated feeding times, spent more money on dinner, less diverse food choices, as well as eating breakfast less frequently, and preferred to eat only lunch and dinner, compared with HCs. Moderate-severe depression was found to be negatively associated with the daily 3 regular meals pattern (breakfast-lunch-dinner pattern; OR 0.467, 95% CI 0.239-0.912), and mild depression was positively associated with daily lunch and dinner pattern (OR 1.460, 95% CI 1.016-2.100). These changes in digital dietary behaviors were able to detect mild and moderate-severe depression (accuracy=0.53, precision=0.60), with better accuracy for detecting moderate-severe depression (accuracy=0.67, precision=0.64). CONCLUSIONS: This is the first study to develop a profile of changes in digital dietary behaviors in individuals with depression using real-world behavioral monitoring. The results suggest that digital markers may be a promising approach for detecting depression.

Proteomics Platform Reveals Broad-Spectrum Nanobodies for SARS-CoV-2 Variant Neutralization.

The ongoing evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to the emergence of different variants of concerns with immune evasion that have been prevalent over the past three years. Nanobodies, the functional variable regions of camelid heavy-chain-only antibodies, have garnered interest in developing neutralizing antibodies due to their smaller size, structural stability, ease of production, high affinity, and low immunogenicity, among other characteristics. In this work, we describe an integrated proteomics platform for the high-throughput screening of nanobodies against different SARS-CoV-2 spike variants. To demonstrate this platform, we immunized a camel with subunit 1 (S1) of the wild-type spike protein and constructed a nanobody phage library. The binding and neutralizing activities of the nanobodies against 72 spike variants were then measured, resulting in the identification of two nanobodies (C-282 and C-39) with broad neutralizing activity against six non-Omicron variants (D614G, Alpha, Beta, Gamma, Delta, Kappa) and five Omicron variants (BA.1-5). Their neutralizing capability was validated using in vitro pseudovirus-based neutralization assays. All these results demonstrate the utility of our proteomics platform to identify new nanobodies with broad neutralizing capability and to develop a treatment for patients with SARS-CoV-2 variant infection in the future.

Maternal care utilization and provision during the COVID-19 pandemic: Voices from minoritized pregnant and postpartum women and maternal care providers in Deep South.

BACKGROUND: The COVID-19 pandemic has significantly affected maternal care services especially for minoritized individuals, creating challenges for both service users (i.e., African American and Hispanic pregnant/postpartum women) and maternal care providers (MCPs). Guided by a socioecological framework, this study aims to investigate the experiences of African American and Hispanic pregnant and postpartum women, as well as MCPs, in accessing and providing maternal care services during the COVID-19 pandemic in the Deep South. METHODS: We conducted semi-structured interviews with 19 African American women, 20 Hispanic women, and 9 MCPs between January and August 2022. Participants were recruited from Obstetrics and Gynecology clinics, pediatric clinics, and community health organizations in South Carolina, and all births took place in 2021. Interview transcripts were analyzed thematically. RESULTS: Maternal care utilization and provision were influenced by various factors at different socioecological levels. At the intrapersonal level, women's personal beliefs, fears, concerns, and stress related to COVID-19 had negative impacts on their experiences. Some women resorted to substance use as a coping strategy or home remedy for pregnancy-induced symptoms. At the interpersonal level, family and social networks played a crucial role in accessing care, and the discontinuation of group-based prenatal care had negative consequences. Participants reported a desire for support groups to alleviate the pressures of pregnancy and provide a platform for shared experiences. Language barriers were identified as an obstacle for Hispanic participants. Community-level impacts, such as availability and access to doulas and community health workers, provided essential information and support, but limitations in accessing doula support and implicit bias were also identified. At the institutional level, mandatory pre-admission COVID-19 testing, visitation restrictions, and reduced patient-MCP interactions were women's common concerns. Short staffing and inadequate care due to the impact of COVID-19 on the health care workforce were reported, along with anxiety among MCPs about personal protective equipment availability. MCPs emphasized the quality of care was maintained, with changes primarily attributed to safety protocols rather than a decline in care quality. CONCLUSION: The pandemic has disrupted maternal care services. To overcome these issues, health facilities should integrate community resources, adopt telehealth, and develop culturally tailored education programs for pregnant and postpartum women. Supporting MCPs with resources will enhance the quality of care and address health disparities in African American and Hispanic women.

Observing heroic behavior and its influencing factors in immersive virtual environments.

Studying heroism in controlled settings presents challenges and ethical controversies due to its association with physical risk. Leveraging virtual reality (VR) technology, we conducted a three-study series with 397 participants from China to investigate heroic actions. Participants unexpectedly witnessed a criminal event in a simulated scenario, allowing observation of their tendency to physically intercept a thief. We examined situational factors (voluntariness, authority, and risk) and personal variables [gender, impulsivity, empathy, and social value orientation (SVO)] that may influence heroism. Also, the potential association between heroism and social conformity was explored. In terms of situational variables, voluntariness modulated participants' tendency to intercept the escaping thief, while perceived risk demonstrated its impact by interacting with gender. That is, in study 3 where the perceived risk was expected to be higher (as supported by an online study 5), males exhibited a greater inclination toward heroic behavior compared to females. Regarding other personal variables, the tendency to engage in heroic behavior decreased as empathy levels rose among males, whereas the opposite trend was observed for females. SVO influenced heroic behavior but without a gender interaction. Finally, an inverse relationship between heroism and social conformity was observed. The robustness of these findings was partly supported by the Chinese sample (but not the international sample) of an online study 4 that provided written descriptions of VR scenarios, indicating cultural variations. These results advance insights into motivational factors influencing heroism in the context of restoring order and highlight the power of VR technology in examining social psychological hypotheses beyond ethical constraints.