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Platonic-solid-like particles in liquid crystals offer intriguing opportunities for engineering complex materials with tailored properties. Inspired by platonic solids' geometric simplicity and symmetry, these particles possess well-defined shapes such as cubes, tetrahedra, octahedra, dodecahedra, and icosahedra. When dispersed within nematic liquid-crystalline media, these particles interact with the surrounding medium in intricate ways, influencing the local orientational order of liquid crystal molecules. In this work, we implement continuum simulations to study how the combination of particle shape and surface anchoring gives rise to line defects that follow the edges of the particles and how they are affected by the presence of a Poiseuille flow. Platonic-solid-like particles in liquid crystals have shown promise in diverse applications ranging from photonics and metamaterials to colloidal self-assembly and responsive soft materials.
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Spinocerebellar ataxia type 7 (SCA7) is a rare genetic disease characterized by progressive cerebellar syndrome and macular degeneration. In a previous study, we clinically and genetically characterized a group of Mexican patients, which represented one of the largest cohorts of SCA7 patients worldwide and demonstrated that all patients had a unique genetic origin. Our laboratory developed a program for the diagnosis, medical care, and long-term follow-up of these patients living in Veracruz State, and in this report, we present an update to this research, covering 2013 to 2024. So far, we identified 172 SCA7 carriers, with a few cases outside Veracruz, and our data support that the length of the CAG repeat tract mainly determines disease severity and life expectancy, and accordingly, we define three different phenotypes, early-onset (EO), classical-onset (CO), and late-onset (LO), with EO patients showing the lowest life expectancy. Furthermore, we found that parental transmission of mutant alleles leads to increased CAG repeat instability, compared to maternal ones. Interestingly, a haplotype analysis revealed that patients outside Veracruz may have different genetic origins. In conclusion, longitudinal observations of SCA7 patients provide insight into the natural history of SCA7 and help to design strategies for diagnosis, genetic counseling, physical rehabilitation, and therapeutic alternatives.
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Doenças Raras , Ataxias Espinocerebelares , Humanos , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/epidemiologia , Ataxias Espinocerebelares/terapia , Ataxias Espinocerebelares/diagnóstico , México/epidemiologia , Feminino , Masculino , Doenças Raras/genética , Doenças Raras/terapia , Doenças Raras/diagnóstico , Doenças Raras/epidemiologia , Adulto , Pessoa de Meia-Idade , Fenótipo , Expansão das Repetições de Trinucleotídeos , Haplótipos , Idade de InícioRESUMO
The self-assembly of liquid crystal droplets and shells represents a captivating frontier in soft matter physics, promising precision engineering of functional materials. In this study, we delve into the phase behavior and investigate defect formation patterns in spherical shell-confined discotic liquid crystals (DLCs) through NpT Monte Carlo simulations. These shells are created by confining DLCs between two spherical surfaces, promoting the same anchoring. In this study, we focus on the case when both surfaces promote edge-on (planar) anchoring. Our study confirms a general result which states that, when a liquid crystal is under strong confinement, the nature of the isotropic-nematic transition changes from first order into continuous. Furthermore, as expected, topological defects at the spherical surface arise due to the topological constraints on the director field. Notably, our investigation reveals a unique topological defect configuration, characterized by the formation of four disclination lines that bridge the inner and external surfaces. Additionally, we observe a mixed ±1/2 wedge-twist disclination line that forms an arch that terminates at the outer surface. This arch decreases its length with decreasing temperature to eventually disappear.
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Sechium edule (Jacq.) Swartz is a perennial herbaceous climbing plant with tendrils and tuberous roots belonging to the Cucurbitaceae family. Its fruits ("chayote"), stems, roots, and leaves are edible and are commonly ingested by humans. It has shown medicinal properties attributed to its bioactive compounds (vitamins, phenolic acids, flavonoids, carotenoids, triterpenoids, polyphenolic compounds, phytosterols, and cucurbitacins), which together have been associated with the control and prevention of chronic and infectious diseases, highlighting its antibacterial, anti-cardiovascular/antihypertensive, antiepileptic, anti-inflammatory, hepatoprotective, antiproliferative, and antioxidant activities. The objective of the study was to determine the antigenotoxic potential of two types of fresh chayote juice (filtered (FChJ) and unfiltered (UFChJ)) against DNA damage produced by benzo[a]pyrene (B[a]P) using an in vivo mouse peripheral blood micronucleus assay (MN). The juices were consumed freely for 2 weeks. A negative control, a control group of each juice, a positive batch [B[a]P], and two combined batches (B[a]P plus FChJ or UFChJ) were included. Blood smears were stained and observed under a microscope to quantify the number of micronucleated normochromic erythrocytes (MNNEs). The results indicate: (a) B[a]P increased the frequency of MNNEs and reduced the rate of PEs; and (b) no juice produced toxic effects or induced MN. On the contrary, both juices were genoprotective. However, the most significant effect was presented by UFChJ at the end of the experiment (70%). It is suggested that UFChJ has a greater amount of fiber and/or phytochemicals that favor the therapeutic effect. Possibly, the genoprotection is also related to its antioxidant capacity.
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Plyometric training in football is essential for enhancing athletic performance, as it allows for increasing strength and speed in gameplay. Meanwhile, mental visualization improves players' technical play and motor performance during both training and competitions, thereby contributing to an overall sports performance enhancement. Collectively, physical and technical training is thought to boost athletes' confidence in facing competitive demands. Our aim in the present study was to analyze the effectiveness of mental visualization during a plyometric training program for improving strength speed, and competitive self-confidence in young adult football (soccer) players. Our sample consisted of 40 male players aged between 19 and 25 years (M = 20.82; SD = 1.26). We used a quasi-experimental design with a control group and pretest/posttest measurements. The experimental group participated in an 8-week plyometric training program that incorporated visualization tasks, while the control group underwent the same program but without visualization exercises. We found significant improvements for the experimental group on vertical jump (p = .047) and speed (50-m sprints) (p < .034) tests, as well as in their perceived competitive self-confidence (p < .017). These findings suggest that combining plyometric exercises with visualization tasks may contribute to better motor learning, increased lower limb muscle speed and strength, and self-confidence to face competition.
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Offshore volcanic activity occurs when an underwater volcano erupts. These volcanoes can be located underwater or on land and can be very dangerous to marine life. The aim of this study is to examine whether the influence of two volcanoes has an effect on the concentrations of metals and trace elements in the Atlantic mackerel Scomber colias in the Canary Islands. For the study, ten specimens of S. colias were obtained from each sampling area in March 2022. Metal concentrations were determined by inductively coupled plasma optical emission spectrophotometry (ICP-OES). The specimens of Scomber colias from the area affected by the Tajogaite volcano (La Palma) showed higher concentrations of all metals and trace elements analyzed than those from the other study areas. The specimens from the area of influence of the Tagoro Volcano (El Hierro) showed the second highest concentration of the elements studied, although this volcanic process is in a state of degassing.
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Monitoramento Ambiental , Metais , Erupções Vulcânicas , Animais , Metais/análise , Perciformes , Poluentes Químicos da Água/análise , Espanha , Oligoelementos/análiseRESUMO
BACKGROUND: The burden of antimicrobial resistance (AMR) in Latin America is high. Little is known about healthcare workers' (HCWs) knowledge, attitudes, and perceptions of antimicrobial stewardship (AS), AMR, and antibiotic use (AU) in the region. METHODS: HCWs from 42 hospitals from 5 Latin American countries were invited to take an electronic, voluntary, anonymous survey regarding knowledge, attitudes, and perceptions of AS, AMR, and AU between March-April 2023. FINDINGS: Overall, 996 HCWs completed the survey (52% physicians, 32% nurses, 11% pharmacists, 3% microbiologists, and 2% "other"). More than 90% of respondents indicated optimizing AU was a priority at their healthcare facility (HCF), 69% stated the importance of AS was communicated at their HCF, and 23% were unfamiliar with the term "antibiotic stewardship". Most (> 95%) respondents acknowledged that appropriate AU can reduce AMR; however, few thought AU (< 30%) or AMR (< 50%) were a problem in their HCF. Lack of access to antibiogram and to locally endorsed guidelines was reported by 51% and 34% of HCWs, respectively. Among prescribers, 53% did not consider non-physicians' opinions to make antibiotic-related decisions, 22% reported not receiving education on how to select antibiotics based on culture results and 60% stated patients and families influence their antibiotic decisions. CONCLUSIONS: Although HCWs perceived improving AU as a priority, they did not perceive AU or AMR as a problem in their HCF. AS opportunities include improved access to guidelines, access to AMR/AU data, teamwork, and education on AS for HCWs and patients and families.
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Antibacterianos , Gestão de Antimicrobianos , Atitude do Pessoal de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Humanos , Estudos Transversais , América Latina , Antibacterianos/uso terapêutico , Feminino , Pessoal de Saúde/psicologia , Masculino , Inquéritos e Questionários , Adulto , Pessoa de Meia-IdadeRESUMO
High-risk pregnancies elevate maternal stress, impacting offspring neurodevelopment and behavior. This study, involving 112 participants, aimed to compare perceived stress, neurodevelopment, and behavior in high-risk and low-risk pregnancies. Two groups, high-risk and low-risk, were assessed during pregnancy for stress using hair cortisol and psychological analysis. At 24 months post-birth, their children's neurodevelopment and behavior were evaluated. Results revealed higher perceived stress and pregnancy-related concerns in high-risk pregnancies, contrasting with low-risk pregnancies. Offspring from high-risk pregnancies displayed elevated internalizing behavior scores, while low-risk pregnancies showed higher externalizing behavior scores. Additionally, women in low-risk pregnancies exhibited increased cortisol concentrations 24 months post-delivery. These findings underscore the necessity for early stress detection and prevention programs during pregnancy, particularly in high-risk cases, to enhance maternal and infant health.
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Inflammation is the immune system's first biological response to infection, injury, or irritation. Evidence suggests that the anti-inflammatory effect is mediated by the regulation of various inflammatory cytokines, such as nitric oxide, interleukins, tumor necrosis factor alpha-α, interferon gamma-γ, as well as the non-cytokine mediator, prostaglandin E2. Currently, the mechanism of action and clinical usefulness of phytochemicals is known; their action on the activity of cytokines, free radicals, and oxidative stress. The latter are of great relevance in the development of diseases, such that the evidence collected demonstrates the beneficial effects of phytochemicals in maintaining health. Epidemiological evidence indicates that regular consumption of fruits and vegetables is related to a low risk of developing cancer and other chronic diseases.
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The objective of this study was to analyse the correlations among the sports psychological profile, competitive anxiety, self-confidence and the flow state of young football players. Additionally, potential distinctions based on age category, competitive level and field position were explored. This study included 328 participants divided into two groups: Group 1, 14-15 year olds, and Group 2, 16-18 year olds (M = 15.85; SD = 1.44). Data were collected by using the Psychological Inventory of Sports Execution (IPED), the Revised Competitive State Anxiety Inventory-2 (CSAI-2R) and the Flow State Scale (FSS). The findings revealed positive associations between the sports psychological profile and self-confidence, as well as with the flow state. Conversely, competitive anxiety demonstrated negative relationships with the sports psychological profile, self-confidence and the state of flow. Moreover, superior scores were observed in the analysed variables for the older age category and higher competitive level, with no notable disparities based on field positions. These results underscore the interplay of psychological factors in the performance of football players and underline distinctions among players according to their category (age and level). This emphasises the importance of scrutinising these variables in athletes to comprehend their profiles and enable targeted interventions aimed at enhancing their psychological resources for competitive scenarios.
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Neuroendocrine tumors comprise a range of neoplasms with varying spectra of origin, biological activity, clinical features, and histological appearance. In this case report, we present a pregnant 33-year-old female who was brought to the emergency department (ED) complaining of acute right iliac fossa pain accompanied by diarrhea and vomiting. Initial management showed no improvement. Lab results, clinical history, and physical exam were suggestive of appendicitis, so an exploratory minimally invasive laparoscopic exam was performed. The histopathological analysis of the excised appendix confirmed the diagnosis of acute appendicitis and periappendicitis. Incidentally, a 0.6 cm neuroendocrine tumor (carcinoid tumor) was identified on the wall of the appendiceal tip. The tumor extended at multiple points into the subserosal fat, and the serous surface and the resection margin were negative for the tumor. After seven days of the initial procedure, the patient presented with abdominal pain and a fever. An abdominal ultrasound was performed, revealing the presence of free fluid. A second exploratory laparoscopy revealed adhesions between the fallopian tubes and cecum, as well as a collection of purulent fluid. The management consisted of adhesiolysis, cavity lavage, and drainage, along with antibiotic therapy, pain management, and close monitoring of the mother's and fetus's status. The patient had a successful recovery and was discharged home a week after surgery. She gave birth to a full-term, healthy baby and remains free of tumor relapse. This case highlights the importance of obtaining histopathological interpretation of any extracted tissue during surgery. Guidelines regarding the management of carcinoids during pregnancy are not available, and when considering surgical intervention, an open or laparoscopic approach must be carefully evaluated.
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This study investigates the impact of varying environmental conditions on the metal composition within the tissues of Sparisoma cretense, contributing to the understanding necessary to offer scientifically sound advice regarding the health status of this species. This knowledge extends beyond fishery production, encompassing implications for food security. The data span the years 2022 and 2023, encompassing both cold and warm climatic seasons. The concentrations of various metals, such as Al, Zn, Cd, Pb, Fe, and Cu, exhibited noteworthy variations across the islands, with significant increases recorded in 2023, particularly during the warm season. The intricate interplay between multiple factors shaped the availability of the analyzed elements in S. cretense. Factors such as rising temperatures during the warm season increased biological activity in marine ecosystems, seasonal fluctuations in weather conditions, water quality, and anthropogenic influences, all contributing to the observed variations in metal concentrations. Additionally, the geological composition of each island and the patterns of marine currents and sediment transport play pivotal roles in these differences. Comprehensive scientific research, monitoring, and environmental surveillance are essential for a holistic understanding of this variability and providing valuable insights for the conservation and management of marine ecosystems in the Canary archipelago.
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According to the available ethnobotanical data, the Bouvardia ternifolia plant has long been used in Mexican traditional medicine to relieve the symptoms of inflammation. In the present study, the cytotoxic effect of extracts obtained from the flowers, leaves and stems of B. ternifolia using hexane, ethyl acetate (AcOEt) and methanol (MeOH) was evaluated by applying them to the SiHa and MDA-MB-231 cancer cell lines. An MTT reduction assay was carried out along with = biological activity assessments, and the content of total phenols, tannins, anthocyanins, betalains and saponins was quantified. According to the obtained results, nine extracts exhibited a cytotoxic effect against both the SiHa and MDA lines. The highest cytotoxicity was measured for leaves treated with the AcOEt (ID50 of 75 µg/mL was obtained for MDA and 58.75 µg/mL for SiHa) as well as inhibition on ABTSâ¢+ against DPPH⢠radical, while MeOH treatment of stems and AcOEt of flowers yielded the most significant antioxidant capacity (90.29% and 90.11% ABTSâ¢+ radical trapping). Moreover, the highest phenolic compound content was measured in the stems (134.971 ± 0.294 mg EAG/g), while tannins were more abundant in the leaves (257.646 mg eq cat/g) and saponins were most prevalent in the flowers (20 ± 0 HU/mg). Screening tests indicated the presence of flavonoids, steroids, terpenes and coumarins, as well as ursolic acid, in all the studied extracts. These results demonstrate the biological potential of B. ternifolia.
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AIM: This study aimed to analyse the psychological impact of the COVID-19 pandemic on pregnant women according to the pregnancy trimester, comparing their psychopathological symptomatology, pregnancy-specific stress, resilience and perceived stress to those of women pregnant before the pandemic. METHODS: A total of 797 pregnant women participated in the study, one group of 393 women pregnant before the pandemic and the other of 404 women pregnant during the pandemic. Student-t test was used to analyse continuous data and the Chi-square test was used for categorical data. RESULTS: Psychopathological symptomatology was significantly higher in six subscales of the SCL-90-R in pregnant women during COVID-19: somatisation, interpersonal sensitivity, depression, anxiety, phobic anxiety, obsessions-compulsions, mainly on the first two trimesters. There is also a higher level of pregnancy-specific stress in pregnant women during the pandemic on the first two trimesters, most likely due to the hypervigilance and fears related to the COVID-19 disease. Nevertheless, perceived stress, usually elevated during pregnancy, was lower in women pregnant during the pandemic in comparison to those pregnant before, as a positive consequence of being on lockdown and diminishing the exposure to daily stressful situations. CONCLUSIONS: Knowing the struggles these women go through during each trimester of pregnancy can be the key to a better health professional-patient relationship, consequently having a positive impact on their mental and physical health.
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BACKGROUND: Prenatal stress could have serious consequences on maternal and fetal health. In this sense, some studies have stated that maternal HCC during pregnancy could contribute to sex-specific effects on infant neurodevelopment, following the Developmental Origins of Health and Disease Hypothesis. AIM: This study aimed to determine whether maternal hair cortisol concentration (HCC) during each trimester of pregnancy and postpartum could predict the neurodevelopmental outcomes of their 12-month-old offspring, with sex-specific differences considered. STUDY DESIGN: longitudinal. SUBJECTS: The study involved 93 pregnant women and their babies. OUTCOME MEASURE: Hair samples collected during each trimester and postpartum and The Bayley Scales for Infant Development III was used to assess the infants' abilities. RESULTS: The results showed that maternal HCC during the first and second trimesters could predict language and motor abilities. However, when discriminated by sex, only females' cognitive, expressive language, and fine and gross motor skills were predicted by cortisol, not males. CONCLUSIONS: These findings support the idea that non-toxic levels of cortisol can positively influence infants' neurodevelopment.
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Hidrocortisona , Efeitos Tardios da Exposição Pré-Natal , Lactente , Masculino , Criança , Humanos , Gravidez , Feminino , Gestantes , Cuidado Pré-Natal , FetoRESUMO
Since ancient times, the shells of marine molluscs have been used as a therapeutic and/or prophylactic resource. In Spain, they were part of practical guides for doctors or pharmacists until the 19th century. In general, seashells were prepared by dissolving in vinegar and were part of plasters or powders used as toothpaste, or to treat dyspepsia, heartburn and leprosy. Thus, the nacre or mother-of-pearl of various molluscs was regularly used in the Royal Colleges of Surgery and in hospitals during the times of the Cortes of Cadiz, as a medicine in galenic preparations based on powders. In contemporary Spanish ethnomedicine, seashells, with a high symbolic value, have been used as an amulet to prevent cracks in the breasts and promote their development during lactation, to avoid teething pain in young children, to eliminate stains on the face or to cure erysipelas. But, as in other countries, products derived from seashells have also been empirically applied. The two resources used traditionally have been the cuttlebone, the internal shell of cuttlefish and the nacre obtained from the external shells of some species. Cuttlebone, dried and pulverised, has been applied externally to cure corneal leukoma and in dental hygiene. In the case of nacre, a distinction must be made between chemical and physical remedies. Certain seashells, macerated in lemon juice, were used in coastal areas to remove spots on the face during postpartum. However, the most common practice in Spain mainland was to dissolve mother-of-pearl buttons in lemon juice (or vinegar). The substance thus obtained has been used to treat different dermatological conditions of the face (chloasma, acne), as well as to eliminate freckles. For the extraction of foreign bodies in the eyes, a very widespread traditional remedy has been to introduce small mother-of-pearl buttons under the lid. These popular remedies and practices are compared with those collected in classic works of medicine throughout history, and data on the pharmacological activity and pharmaceutical applications of the products used are provided. The use of cuttlebone powders is supported by different works on anti-inflammatory, immune-modulatory and/or wound healing properties. Nacre powder has been used in traditional medicines to treat palpitations, convulsions or epilepsy. As sedation and a tranquilisation agent, nacre is an interesting source for further drug development. Likewise, nacre is a biomaterial for orthopaedic and other tissue bioengineering applications. This article is a historical, cultural and anthropological view that can open new epistemological paths in marine-derived product research.
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Four new natural chemical entities, including 2-hydroxy-α-truxillic acid (2), (3R,4S)-2,2-dimethyl-3-hydroxy-4-(1-angeloyloxy)-6-acetyl-7-methoxychromane (3), N-tricosanoyltyramine (4), and grandifolamide (5), were isolated along with 11 known compounds (1, 6-15) from the aerial parts of Ageratina grandifolia. The chemical structures were elucidated using chemical derivatization and HR-MS, NMR, and DFT-calculated chemical shifts, combined with DP4+ statistical analysis. It was found that 2 decomposed into its biogenetic precursor, o-coumaric acid, upon standing at room temperature for a few weeks. 3,5-Diprenyl-4-hydroxyacetophenone (8), O-methylencecalinol (10), encecalin (11), and encecalinol (12) bound to calmodulin (CaM) with higher affinity than chlorpromazine, a well-known CaM inhibitor. Molecular dynamics studies revealed that the complexes of these compounds with CaM remained stable during the simulation. Altogether these results revealed the therapeutic and research tool potential of compounds 8, 10, 11, and 12.
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Ageratina , Ageratina/química , Calmodulina/química , Calmodulina/metabolismo , Calmodulina/farmacologia , Simulação de Dinâmica Molecular , Espectroscopia de Ressonância Magnética , Estrutura MolecularRESUMO
Blue phase (BP) liquid crystals represent a fascinating state of soft matter that showcases unique optical and electro-optical properties. Existing between chiral nematic and isotropic phases, BPs are characterized by a three-dimensional cubic lattice structure resulting in selective Bragg reflections of light and consequent vivid structural colors. However, the practical realization of these material systems is hampered by their narrow thermal stability and multi-domain crystalline nature. This feature article provides an overview of the efforts devoted to stabilizing these phases and creating monodomain structures. In particular, it delves into the complex relationship between geometrical confinement, induced curvature, and the structural stability and photonic features of BPs. Understanding the interaction of curved confinement and structural stability of BPs proves crucially important for the integration of these materials into flexible and miniaturized devices. By shedding light on these critical aspects, this feature review aims to highlight the significance of understanding the coupling effects of physical and mechanical forces on the structural stability of these systems, which can pave the way for the development of efficient and practical devices based on BP liquid crystals.
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Hyper-reactive malarial splenomegaly (HMS), or tropical splenomegaly syndrome, is a severe complication of chronic and recurrent infections caused by Plasmodium spp. This condition typically results in splenomegaly greater than or equal to 10 cm and a constellation of laboratory findings, including the absence of identifiable parasites in peripheral blood smears. However, patients with HMS demonstrate serological or molecular evidence of infection. Despite being a familiar entity in malaria holoendemic countries in Africa, and regions of Papua New Guinea, the pathophysiology, natural history, and treatment of the syndrome remains to be fully elucidated. Herein, we describe a highly suggestive case of HMS in a Senegalese patient migrating northbound to reach the U.S.-Mexico border and for whom we provided medical care during his crossing of the Darien Gap in Panama. We also reviewed the literature on diagnosing and treating HMS in-depth.