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OBJECTIVE: To better understand early etiological pathways to trajectories of child exposure to community violence (CECV), we used person-centered latent class growth analysis (LCGA) to examine chronicity of CECV from early school age through early adolescence, and examined early risks of the identified CECV trajectories (i.e., prenatal cocaine exposure, harsh parenting and caregiving instability across infancy and early childhood, and child activity level and inhibitory control at kindergarten age). METHOD: An at-risk sample (N = 216; 110 girls) of primarily low-income participants (76% on Temporary Assistance for Needy Families) with high rates of prenatal substance exposure was used. The majority of the mothers were African American (72%), had high school or below education (70%), and were single (86%). Postnatal assessments occurred at eight time points during infancy and toddlerhood, early childhood through early school age, and early adolescence. RESULTS: We identified two distinct linearly increasing CECV trajectories (high-exposure and low-exposure). An interaction between child activity level and maternal harshness emerged, such that children with high activity levels and experiencing high harshness had the highest probabilities of being in the high exposure-increasing trajectory, in addition to early caregiving instability (conditional effect). CONCLUSION: The current findings not only have important theoretical implications but also provide insights into early intervention.

This paper presented a mathematical model to describe the production of fucoxanthin by alga Thalassiosira weissflogi ND-8 in photobioreactor. Our interest was focused on characterizing the effects of nitrogen and phosphorus on the growth of microalgae and on the synthesis of fucoxanthin. The rate equations of microalgal growth, fucoxanthin synthesis and substrate consumptions were formulated. Kinetic parameters of the model and their sensitivities with respect to model output were estimated. The predicted results were compared with experimental data, which showed that this model closely agrees with actual experiment and is able to reflect the growth and metabolism characteristics of microalgae. Our results also indicated that nitrogen plays a major role in the synthesis of fucoxanthin, and the synthesis of fucoxanthin is partially linearly related to the consumption of nitrogen. Phosphorus is primarily consumed in the growth and metabolism of microalgal cells, while excessive phosphorus concentration has an inhibitory effect on the growth of microalgae.

OBJECTIVE: Alexithymia is common among people who abuse alcohol, yet the mechanisms by which alexithymia exerts its influence remain unclear. This analysis tested a model whereby the three subscales of the Toronto Alexithymia Scale exert an indirect effect on alcohol problems through difficulties with emotion regulation and psychological distress. METHOD: Men and women (n=141) seeking alcohol use disorder (AUD) treatment completed the Toronto Alexithymia Scale, the Difficulties with Emotion Regulation Scale, the Brief Symptom Inventory, the Short Inventory of Problems, and the Alcohol Dependence Scale. RESULTS: The Difficulty Identifying Feelings subscale of the Toronto Alexithymia Scale was positively associated with alcohol problems through emotion dysregulation and psychological distress. The other two subscales, Difficulty Describing Feelings and Externally-oriented Thinking, were not associated with any other variables. CONCLUSION: People with alexithymia may consume alcohol to help regulate undifferentiated states of emotional arousal. Given the prevalence of alexithymia among people who abuse alcohol, treatment supplements that enhance the identification of emotions are needed.

OBJECTIVE: Research has identified several potential mechanisms of behavior change (MOBCs) in cognitive–behavioral therapy for alcohol use disorder, including alcohol abstinence self-efficacy (AASE), negative affect (NA), and positive affect (PA). However, little is known about when MOBCs affect clinical outcomes during alcohol use disorder treatment. Such information could advance MOBC research by identifying relationships between specific treatment content and variations in MOBCs. This study examined three MOBCs simultaneously to determine their timing and relative influence on percent days abstinent (PDA) and drinks per day (DPD). METHOD: Data were derived from a parent study assessing pretreatment change in drinking. Participants (n = 205) received 12 sessions of cognitive–behavioral therapy for alcohol use disorder. AASE, NA, and PA were measured at each treatment session, and time-varying effect models (TVEM) were used to examine their association with PDA and DPD. RESULTS: All three MOBCs were associated with PDA and DPD but varied with regard to time course, strength, and direction. For PDA, AASE was positively associated throughout treatment, NA was negatively associated from Sessions 1 to 10, and PA was positively associated from Sessions 1 to 3 and 11 to 12. For DPD, AASE was positively associated from Session 5 to the end of treatment, NA was positively associated throughout treatment although the strength of the association varied and was strongest at the beginning of treatment, and PA was positively associated from Sessions 5 to 12. CONCLUSIONS: Results show that MOBCs exert their effects at different times during treatment. In addition to replicating these results, future research should attempt to manipulate MOBCs directly and examine their influence on alcohol outcomes.

Ovarian cancer is the second leading cause of death of female gynecological malignant tumor patients worldwide. Although surgery and chemotherapy have achieved dramatic achievement, the mortality remains high, resulting in the demand for new specific drug discovery. Disrupting ovarian cancer growth

Self-reported tiredness or low energy, often referred to as fatigue, has been linked to lifestyle factors, although data from randomized–controlled trials are lacking. We investigate whether modifiable lifestyle factors including smoking and alcohol intake related exposures (SAIEs) are causal factors for fatigue using Mendelian randomization (MR). A two-sample MR study was performed by using genome-wide association summary results from UK Biobank (UKBB), and each of the sample size is more than 100,000. We used the inverse variance weighted method, and sensitivity analyses (MR Egger, weighted median and penalized median estimators) to account for pleiotropy. The two-sample MR analyses showed inverse causal effect of never-smoking status and positive effect of current smoking status on the risk of fatigue. Similarly, genetically predicted alcoholic intake was positively associated with fatigue. The results were consistent across the different MR methods. Our Mendelian randomization analyses do support that the cessation of smoking and alcohol can decrease the risk of fatigue, and limit alcohol intake frequency can also reduce the risk.Author summaryMany lifestyle factors have been associated with the risk of fatigue, but we cannot ascertain the causality between lifestyle factors and the risk of fatigue; whether the modification of lifestyles will reduce the risk. Another challenge is that fatigue is usually caused by various physiological and pathological factors, so most epidemiological data which examined risk factor modification have not studied the relationship between modifiable risk factors and self-reported tiredness in extensive conditions. SAIEs are the ones of the most influential lifestyle factors for human health and wellbeing. We performed MR analyses to estimate the causal effect of SAIEs on fatigue. In our study, we initially identified genetic variants which are significantly associated with SAIEs. We found SAIEs are causally involved in fatigue. The results could be extremely useful in the context of lifestyle - health relationships.

The purpose of this study was to examine the moderating role of maternal sensitivity on the association between prenatal adversity and externalizing behaviors at 24 months of age in a diverse, high-risk sample. We hypothesized that among children with higher prenatal adversity, high maternal sensitivity would serve as a protective factor. Participants were 247 primarily low-income, diverse dyads. Results indicated a significant interaction effect of maternal sensitivity and prenatal adversity on externalizing problems. The association between prenatal adversity and externalizing behaviors was significant only among children who experienced low prenatal adversity, with higher maternal sensitivity associated with lower externalizing behaviors. These findings indicate that, in the absence of high prenatal risk, responsive and sensitive parenting can buffer children in an otherwise high-risk sample from the development of externalizing behaviors.El propósito de este estudio fue examinar el papel moderador que la sensibilidad materna tiene sobre la asociación entre adversidad prenatal y las conductas de externalización a los 24 meses de edad en un grupo muestra diverso y de alto riesgo. Nuestra hipótesis es que entre los niños con más alta adversidad prenatal (PA), una alta sensibilidad materna serviría como un factor de protección. Participaron 247 díadas diversas, primariamente de bajos recursos económicos (173 infantes expuestos a sustancias). Los resultados indicaron un significativo efecto de interacción de la sensibilidad materna y la adversidad prenatal sobre los problemas de externalización. La asociación entre la adversidad prenatal y las conductas de externalización fue significativa sólo entre niños que habían experimentado una adversidad prenatal baja, mientras que una más alta sensibilidad materna se asoció con más bajas conductas de externalización. Estos resultados indican que, en ausencia de un riesgo prenatal alto, una crianza receptiva y sensible puede amortiguar el desarrollo de conductas de externalización en niños que, de lo contrario, están dentro de un grupo muestra de alto riesgo.Le but de cette étude était d'examiner le rôle modérateur de la sensibilité maternelle sur l'association entre l'adversité prénatale et les comportements d'externalisation à l’âge de 24 mois chez un échantillon varié, et à haut risque. Nous avons pris comme hypothèse que chez les enfants avec une adversité prénatale élevée (PA), une sensibilité maternelle élevée servirait de facteur de protection. Les participants ont consisté en 247 dyades diverse et principalement issues de milieux défavorisés (173 bébés exposés à la toxicomanie). Les résultats indiquent un effet d'interaction important de la sensibilité maternelle et de l'adversité prénatale sur les problèmes d'externalisation. Le lien entre l'adversité prénatale et les comportements d'externalisation n’était important que chez les enfants ayant fait l'expérience d'une adversité prénatale peu élevée, avec une sensibilité maternelle plus élevée liée à des comportements d'externalisation moins élevés. Ces résultats indiquent que, en l'absence d'une risque prénatal élevé, le parentage réactif et sensible peut servir de tampon aux enfants contre le développement de comportements d'externalisation dans un échantillon qui est par ailleurs à haut risque.Die Auswirkung pränataler Belastung auf externalisierendes Verhalten im Alter von 24 Monaten in einer Stichprobe mit hohem Risiko: Mütterliche Sensibilität als Moderator Ziel dieser Studie war es, die moderierende Rolle mütterlicher Sensibilität im Zusammenhang zwischen pränataler Belastung und Externalisierungsverhalten im Alter von 24 Monaten in einer diversen Stichprobe mit hohem Risiko zu untersuchen. Die Hypothese bestand darin, dass bei Kindern mit höherer pränataler Belastung (prenatal adversity; PA) eine hohe Sensibilität der Mutter als Schutzfaktor dient. 247 hauptsächlich einkommensschwache, diverse Mutter-Kind Dyaden (173 davon substanzexponierte Säuglinge) nahmen an der Studie teil. Die Ergebnisse zeigten einen signifikanten Interaktionseffekt von mütterlicher Sensibilität und pränataler Belastung auf Externalisierungsprobleme. Der Zusammenhang zwischen pränataler Belastung und Externalisierungsverhalten war nur bei Kindern signifikant, bei denen eine geringe pränatale Belastung vorhanden war, wobei eine höhere Sensibilität der Mutter mit einem geringeren Externalisierungsverhalten assoziiert war. Diese Ergebnisse deuten darauf hin, dass, wenn kein hohes pränatales Risiko vorhanden ist, ein responsives und sensibles elterliches Verhalten Kinder in einer ansonsten risikoreichen Stichprobe vor der Entwicklung von Externalisierungsverhalten schützen kann.ハイリスク群の生後24ヶ月における外在化型の問題行動に対する出生前の困難な 課題の影響:緩和する役としての母親の感受性 本論文の目的は、多様でハイリスク群の出生前の困難な課題と生後24ヶ月における外在化型の問題行動の関連に対する母親の感受性の緩和する役割について調査することであった。我々は、より高い出生前の困難な課題(PA)のある子どもの中で、母親の高い感受性が予防要素として役立つのではないだろうかと仮定した。対象者は主に低収入で 多様な背景をもつ母子親子247組(173人の薬物曝露の新生児)である。結果は、外在化型の問題行動に対して母親の感受性と出生前の困難な課題との有意な相互作用の影響が示唆された。出生前の困難な課題と外在化型の問題行動の間の関連は、出生前の困難な課題を少なく体験した子どもの中で、外在化型の問題行動が低いことに関連した母親の感受性がより高いことのみ有意であった。これらの結果は、出生前の高いリスクがない場合において、応答的で感受性豊かな子育てが、それでもハイリスク群には入る子どもを外在化型の問題行動の発達から子どもを守ることができることを示唆している。.本研究的目的是在一个多样化的高风险样本中, 检验母亲敏感性在产前逆境与儿童24月龄时的外化行为之间的调节作用。我们假设处于更恶劣的产前逆境 (PA)中的儿童, 较高的母亲敏感性可以作为一个保护因素。研究参与者主要是247名低收入、多样化的母婴 (包含173名药物暴露的婴儿) 。结果表明, 母亲敏感性与产前逆境对儿童的外化问题有显著的相互作用。产前逆境与儿童外化行为之间的关联仅在经历过低程度的产前逆境的儿童中才有意义, 较高的母亲敏感性会导致较低的儿童外化行为。这些发现表明, 在没有经历高产前风险的情况下, 反应敏感的育儿可以缓冲儿童外化行为的发展, 否则他们会发展为高风险的样本。.تأثير الشدائد السابقة للولادة على السلوكيات السلبية في عمر 24 شهرًا في عينة عالية المخاطرة: حساسية الأمهات كعامل وسيط ملخص كان الغرض من هذه الدراسة هو دراسة الدور الوسيط للحساسية الأمومية في الارتباط بين الشدائد السابقة للولادة والسلوكيات السلبية في عمر 24 شهرًا في عينة متنوعة وعالية المخاطرة. افترضنا أنه بين الأطفال الذين يعانون من الشدائد ما قبل الولادة (PA) ، فإن الحساسية العالية للأمهات ستكون بمثابة عامل وقائي. وكان المشاركون 247 من الثنائيات المتنوعة ذات الدخل المنخفض (173 رضيع من المعرضين للمواد المخدرة). وأشارت النتائج إلى تأثير تفاعلي كبير لحساسية الأمهات والشدائد السابقة للولادة على مشاكل السلوكيات السلبية. كان الارتباط بين الشدائد السابقة للولادة والسلوكيات السلبية مهمًا فقط بين الأطفال الذين عانوا من الشدائد المنخفضة قبل الولادة ، بينما كان ارتفاع حساسية الأم مرتبطاَ بسلوكيات سلبية أقل. وتشير هذه النتائج إلى أنه في غياب مخاطر عالية قبل الولادة، يمكن الرعاية الوالدية المستجيبة والحساسة أن تشكل عامل وقائي للأطفال في عينة عالية الخطورة من تطور سلوكيات سلبية.

Camellia oleifera is an important woody edible oil crop in China with high ecological and economical values. It is a traditional oilseed crop with high levels of desirable fatty acids. The fruits of C. oleifera were harvested from 18 geographic provenances in southern China. In this paper, we analyzed the key environmental factors of diverse geographic provenances that caused the variation in the fruit morphology and fatty acid composition (FAC). Our study indicated an average coefficient of variation of fruit width (FW) of 18.63%, and 15.81% for fruit length (FL). The most abundant fatty acids (FA) were oleic acid (C18:1; 70.21–85.23%), followed by palmitic acid (C16:0; 6.93–13.89%) and linoleic acid (C18:2; 5.02–14.26%). In addition, the fruit width had a negative correlation with the equivalent latitude (ELAT) and a positive correlation with the annual mean air temperature (MAT). The fruit length-to-width ratio and oleic acid level had a positive correlation with ELAT but a negative correlation with MAT, annual precipitation (AP), and precipitation of wettest quarter (PWQ). A positive correlation was observed between MAT, AP, and PWQ with palmitic acid. Meanwhile, a negative correlation was found between longitude (LON), maximum temperature of warmest month (MTW), and ELAT and palmitic acid. The cluster analysis indicated six groups for the selected 18 populations. Our results showed the most influential environmental factors for variation in fruit morphology and FAC are ELAT and MAT.

Molybdenum disulfide (MoS2) has received considerable interests in rechargeable lithium-ion batteries (LIBs) and hydrogen evolution reaction (HER). To overcome the instinct limitations of pristine MoS2, such as low conductivity, poor cyclic stability and rate performance, hybrid carbon-MoS2 composites are often practically applied to improve the electrochemical properties. Herein, a facile, scalable, and durable synthesis method is innovated to inlay MoS2 nanosheets into three-dimensional (3D) fibrous nitrogen-doped carbon spheres (FNCs) for achieving 3D FNC-MoS2 composites. The free-standing 3D FNC-MoS2 nanocomposites can be used as the anode for LIBs. It exhibits a high reversible capacity of ∼700 mA h g−1, and nearly no fading of the capacity nearly after 400 cycles at a current density of 1.2 A g−1. Meanwhile, FNC-MoS2 exhibits superior HER activity accompanied by a small overpotential of around 194 mV in 0.5 M H2SO4. Tafel slopes are estimated to be 54 mV dec−1, and the current density of FNC-MoS2 decreases very slightly compared to the initial one after 1000 cycles. We are convinced that the enhanced Li+ storage performance and HER activity are attributed to the synergistic effects and structural advantages, such as higher specific surface, larger pore volume, radical fibrous structure, and chemical/mechanical stability, achieved from the unique architectures of the title material.

We examined a conceptual model for the associations of prenatal exposure to tobacco (PTE) and marijuana with child reactivity/regulation at 16 months of age. We hypothesized that PTE would be associated with autonomic reactivity and regulation that these associations would be indirect via maternal anger/hostility, depression/stress, or harsh parenting assessed at 2 months and that these effects would be most pronounced among children exposed to both tobacco and marijuana (PTME). Participants were 247 dyads (81 PTE, 97 PTME, and 69 nonexposed) who were followed up at 2 (N = 247) and 16 months (N = 238) of child age. Results from model testing indicated an indirect association between PTME and autonomic functioning during the second year of life, which was mediated by harsh parenting during caregiver-infant interactions. This study fills an important gap in the literature on PTE, PTME, and autonomic regulation during the toddler years, highlighting the role of maternal parenting as important intervening variables.

Aims This study sought to identify phenotypic variations among individuals with alcohol use disorder (AUD) that may, in part, help improve the effectiveness of existing AUD interventions. Methods Latent class analysis was conducted to examine the potential heterogeneity of AUD in a sample (N = 220; Mage = 51.19 years, standard deviation = 9.94; 37.7% female) of treatment-seeking participants diagnosed with AUD using DSM-5 criteria. Results and Conclusions Three distinct patterns of responses to the 11 DSM-5 AUD symptoms emerged: Class 1 (n = 114, 51.8%), Class 2 (n = 78, 35.5%) and Class 3 (n = 28, 12.7%). The identified profiles were further differentiated by demographics, alcohol-related constructs, individual difference characteristics and diagnostic and treatment variables. The findings have implications for refining AUD assessment as well as optimizing personalized treatment.

Researchers have suggested that heritable personality traits may predispose individuals to be willing to engage in the behavior. In particular, previous research has demonstrated a link between bullying perpetration and low levels of the HEXACO personality factor Honesty-Humility, which is a measure of an individual's willingness to exploit others. However, to date, evidence for the importance of low Honesty-Humility (versus low Agreeableness or Emotionality) has been drawn from North American or European samples. The present study attempts to address this gap by comparing data from 440 Chinese adolescents and 350 Canadian adolescents who completed the HEXACO-PR-I personality inventory along with a bullying questionnaire. We predicted that the personality factor Honesty-Humility would be a stronger predictor Chinese and Canadian adolescents' bullying perpetration than would anger (low A) or low empathy, emotional concern, and anxiety (low E). Results of hierarchical linear regressions confirmed that Honesty-Humility, as well as Conscientiousness, were significantly, negatively related to bullying perpetration in both samples. This suggests a cross-cultural profile of bullies as exploitative and impulsive, although Chinese bullies exhibited a more complex relationship with personality that included low Agreeableness and high eXtraversion. Implications of these results for the adaptive theory of bullying are discussed.

The μ-opioid receptor (MOR) is a Gi/o protein-coupled receptor that mediates analgesic, euphoric, and reward effects. Using a bacterial two-hybrid screen, we reported that the carboxyl tail of the rat MOR associates with A20-binding inhibitor of nuclear factor (NF)-κB (ABIN-1) (Zhou et al., 2015). This interaction was confirmed by direct protein - protein binding and co-immunoprecipitation of MOR and ABIN-1 proteins in cell lysates. Saturation binding studies showed that ABIN-1 had no effect on MOR binding. However, the interaction of ABIN-1 and MOR inhibited the activation of G-proteins induced by DAMGO ([D-Ala2,N-Me-Phe4,Gly5-ol]-Enkephalin). MOR phosphorylation, ubiquitination and internalization induced by DAMGO were decreased in Chinese hamster ovary cells that co-expressed MOR and ABIN-1. The suppression of forskolin-stimulated adenylyl cyclase by DAMGO was also inhibited by the interaction of ABIN-1 with MOR. In addition, ERK activation was also negatively regulated by overexpression of ABIN-1. These data suggest that ABIN-1 is a negative coregulator of MOR activation, phosphorylation, and internalization in vitro. ABIN-1 also inhibited morphine-induced hyper-locomotion in zebrafish larvae (AB strain). By utilization of an antisense morpholino oligonucleotide (MO) gene knockdown technology, the ABIN-1 MO-injected zebrafish larvae showed a significant increase (approximately 60%) in distance moved compared with control MO-injected larvae after acute morphine treatment (P

BACKGROUND Few studies have focused on behavioral changes that occur prior to entering treatment for an alcohol use disorder (AUD). In 2 studies (Psychol Addict Behav, 27, 2013, 1159; J Stud Alcohol, 66, 2005, 369), pretreatment reductions in alcohol use were associated with better treatment outcomes. Identifying patterns of pretreatment change has the potential to inform clinical decision making. METHODS This study sought to identify pretreatment change trajectories in individuals seeking outpatient treatment for AUD (N = 205) using finite mixture modeling based on changes in number of days abstinent per week (NDA). RESULTS The analysis identified 3 pretreatment trajectory classes. Class 1 (High Abstinence-Minimal Increase; HA-MI) (n = 64; 31.2%) reported a high level of pretreatment NDA with minimal change during an 8-week pretreatment interval. Class 2 (Low Abstinence-Steady Increase; LA-SI) (n = 73; 35.6%) reported a low level of pretreatment NDA followed by a steady increase beginning 2 weeks prior to the phone screen. Class 3 (Nonabstinent-Accelerated Increase; NA-AI) (n = 68; 33.2%) reported no or very low levels of pretreatment NDA but demonstrated an increase following the phone screen. With regard to within-treatment change, Class 1 demonstrated the least and Class 3 demonstrated the most change in NDA. From baseline to 6-month follow-up, Class 3 added 2.31 abstinent days per week, Class 2 added 0.69 days, and Class 1 added 0.63 days. The increase in NDA for Class 3 was significantly different from the other 2 classes; however, Class 3 reported fewer overall days abstinent at 6-month follow-up. CONCLUSIONS Study results have clinical and research implications including recommended changes to treatment protocols and research designs. Understanding the impact of pretreatment trajectories of alcohol use on within-treatment and posttreatment outcomes may provide important information about adapting treatment to increase efficiency and effectiveness.

Magnetic Fe3O4@ZnO@nitrogen-doped carbon (Fe3O4@ZnO@N-C) composites with multiple core-shell structures have been successfully synthesized by calcination of ZIF-8 coated Fe3O4@ZnO core-shell nanocrystals. The morphologies and microstructural characteristics are investigated by X-ray diffraction, Fourier-transform infrared spectrometer, transmission electron microscopy, X-ray photoelectron spectroscopy, physical adsorption of nitrogen, and UV–vis diffuse reflectance spectroscopy. The photocatalytic performances are tested by degrading methylene blue (MB) in aqueous solutions under the irradiation of imitative sunlight. The photocatalytic trials indicate that the Fe3O4@ZnO@N-C composites exhibit improved degradation efficiency compared to the Fe3O4@ZnO precursor. The photocatalytic efficiencies of the as-prepared Fe3O4@ZnO@N-C composites towards MB are 93% under irradiation of imitative sunlight for 90 min and still maintained to be 87% after 6 recycles, which shows very good stability and recyclability. Nitrogen-doped carbon is believed to extend the absorption spectra to the visible-light region. The photodegradation kinetics via using the as-prepared Fe3O4@ZnO@N-C composite as a novel photocatalyst are systematically investigated.

Aims We examined prospective associations between pre-and-postnatal tobacco and cannabis exposure on child behavior problems from 2 to 3 years of child age, sex differences in these associations, and bidirectional associations between maternal postnatal substance use and child behavior problems across time. Methods The sample consisted of 247 primarily young, unmarried, low-income, minority mothers and their children (97 prenatally exposed to tobacco and cannabis, 81 exposed to tobacco only, and 69 non-exposed). Mothers were assessed during each trimester of pregnancy, at 2, 9, 16 months, 2 and 3 years of child age. Results Bivariate results indicated significant differences mainly for girls. Girls in the prenatal tobacco exposure group had higher internalizing problems compared to the other two groups, and higher attention and sleep problems at 3 years compared to the control group. Higher number of cigarettes per day during pregnancy was significantly associated with higher anxiety/depression and higher attention problems at 3 years, and the associations were stronger for girls compared to boys. In model testing controlling for prenatal exposure, results indicated bidirectional associations between behavior problems at 2 years and maternal postnatal cannabis use, such that higher cannabis use across the infant toddler period predicted higher behavior problems at 2 years, which in turn predicted higher cannabis use a year later. Conclusions Results add to the literature on joint effects of tobacco and cannabis, highlight the importance of considering bidirectional associations between maternal substance use and child behavior problems, and indicate generally stronger prenatal tobacco exposure effects for girls.

The

This chapter explores the application of acoustic emission (AE) testing technique in blowout preventor (BOP) shell. Two problems are presented in this dissertation. First, a tensile test is implemented, using a specimen made of BOP shell material ZG25GrNiMo, and the AE characteristics of the shell material during tensile process are obtained. Then, a pressure test of a BOP shell with crack performed with water and the AE characteristics of the BOP shell during pressure process are obtained. The research shows that the AE frequency spectrums characteristics of BOP shell material are different at different damage stages, and the AE technique can be used to test the damage of BOP shell.