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1.
Geobiology ; 20(4): 465-478, 2022 07.
Article En | MEDLINE | ID: mdl-35584309

Symbioses between metazoans and microbes involved in sulfur cycling are integral to the ability of animals to thrive within deep-sea hydrothermal vent environments; the development of such interactions is regarded as a key adaptation in enabling animals to successfully colonize vents. Microbes often colonize the surfaces of vent animals and, remarkably, these associations can also be observed intricately preserved by pyrite in the fossil record of vent environments, stretching back to the lower Paleozoic (Ordovician-early Silurian). In non-vent environments, sulfur isotopes are often employed to investigate the metabolic strategies of both modern and fossil organisms, as certain metabolic pathways of microbes, notably sulfate reduction, can produce large sulfur isotope fractionations. However, the sulfur isotopes of vent fossils, both ancient and recently mineralized, have seldom been explored, and it is not known if the pyrite-preserved vent organisms might also preserve potential signatures of their metabolisms. Here, we use high-resolution secondary ion mass spectrometry (SIMS) to investigate the sulfur isotopes of pyrites from recently mineralized and Ordovician-early Silurian tubeworm fossils with associated microbial fossils. Our results demonstrate that pyrites containing microbial fossils consistently have significantly more negative δ34 S values compared with nearby non-fossiliferous pyrites, and thus represent the first indication that the presence of microbial sulfur-cycling communities active at the time of pyrite formation influenced the sulfur isotope signatures of pyrite at hydrothermal vents. The observed depletions in δ34 S are generally small in magnitude and are perhaps best explained by sulfur isotope fractionation through a combination of sulfur-cycling processes carried out by vent microbes. These results highlight the potential for using sulfur isotopes to explore biological functional relationships within fossil vent communities, and to enhance understanding of how microbial and animal life has co-evolved to colonize vents throughout geological time.


Hydrothermal Vents , Microbiota , Animals , Fossils , Sulfur/metabolism , Sulfur Isotopes/analysis
2.
J Pers Assess ; 104(3): 320-334, 2022.
Article En | MEDLINE | ID: mdl-34037514

Mature interpersonal decentering is a form of social cognitive role-taking involving reflective thought about one's interpersonal relationships. Previous research examining main effects for persons, card situation content, story content, and person-card interactions found more mature decentering in stories about heterosexual romantic-pull Thematic Apperception Test (TAT) cards (HRC) as compared with stories about nonromantic cards (NRC). To see whether differences in means corresponded to differential criterion validity, this multi-method study examined Inventory of Interpersonal Problems circumplex (IIP-C) scores associated with young adults' decentering maturity and deficits, comparing correlations with IIP-C scores of decentering scores calculated from HRC versus NRC. Similarly, to test the effect of story content, IIP-C scores were correlated with decentering scores calculated from stories having romantic versus nonromantic story content. Using circumplex statistical tests, decentering deficits were associated with domineering/vindictive interpersonal problems, and mature decentering with nonassertive/exploitable problems. Men who reported more exploitable problems decentered more maturely across all situations. Women who decentered more maturely in response to HRC reported more socially avoidant problems, whereas those who decentered more maturely to NRC reported more exploitable problems. Results for romantic versus nonromantic story content were largely uninterpretable (did not meet circumplexity assumption). Findings might assist clinicians' card selection.


Interpersonal Relations , Thematic Apperception Test , Female , Humans , Male , Young Adult
3.
Front Microbiol ; 12: 802991, 2021.
Article En | MEDLINE | ID: mdl-35087502

Limonitic layers of the regolith, which are often stockpiled as waste materials at laterite mines, commonly contain significant concentrations of valuable base metals, such as nickel, cobalt, and manganese. There is currently considerable demand for these transition metals, and this is projected to continue to increase (alongside their commodity values) during the next few decades, due in the most part to their use in battery and renewable technologies. Limonite bioprocessing is an emerging technology that often uses acidophilic prokaryotes to catalyse the oxidation of zero-valent sulphur coupled to the reduction of Fe (III) and Mn (IV) minerals, resulting in the release of target metals. Chromium-bearing minerals, such as chromite, where the metal is present as Cr (III), are widespread in laterite deposits. However, there are also reports that the more oxidised and more biotoxic form of this metal [Cr (VI)] may be present in some limonites, formed by the oxidation of Cr (III) by manganese (IV) oxides. Bioleaching experiments carried out in laboratory-scale reactors using limonites from a laterite mine in New Caledonia found that solid densities of ∼10% w/v resulted in complete inhibition of iron reduction by acidophiles, which is a critical reaction in the reductive dissolution process. Further investigations found this to be due to the release of Cr (VI) in the acidic liquors. X-ray absorption near edge structure (XANES) spectroscopy analysis of the limonites used found that between 3.1 and 8.0% of the total chromium in the three limonite samples used in experiments was present in the raw materials as Cr (VI). Microbial inhibition due to Cr (VI) could be eliminated either by adding limonite incrementally or by the addition of ferrous iron, which reduces Cr (VI) to less toxic Cr (III), resulting in rates of extraction of cobalt (the main target metal in the experiments) of >90%.

4.
PLoS One ; 15(10): e0239779, 2020.
Article En | MEDLINE | ID: mdl-33044971

BACKGROUND: The conditions of diminished ovarian reserve and primary ovarian insufficiency, characterized by poor fertility outcomes, currently comprise a major challenge in reproductive medicine, particularly in vitro fertilization. Currently in the IVF industry, blastocyst developmental success rate per treatment is routinely overlooked when a live birth results from treatment. Limited data are available on this significant and actionable variable of blastocyst development optimization, which contributes to improvement of treatment success Women with elevated basal FSH concentration are reported to still achieve reasonable pregnancy rates, although only a few studies report correlations with blastocysts development. Diagnostic values of AMH/basal FSH concentrations can be useful for determining the optimal stimulation protocol as well as identification of individuals who will not benefit from IVF due to poor prognosis. The objective of this study is to identify actionable clinical and culture characteristics of IVF treatment that influence blastocyst developmental rate, with the goal of acquiring optimal success. METHODS AND FINDINGS: A retrospective observational study was performed, based on 106 women undergoing IVF, regardless of prognosis, over a six-month period from January 1, 2015 to June 31, 2015. Rate of high-quality blastocyst production, which can be used for embryo transfer or vitrification, per normally fertilized oocyte, was evaluated. Treatment was determined successful when outcome was ≥ 40% high-quality blastocysts. The data were initially evaluated with the Evtree algorithm, a statistical computational analysis which is inspired by natural Darwinian evolution incorporating concepts such as mutation and natural selection (see Supplementary Material). The analysis processes all variables simultaneously against the outcome, aiming to maximize discrimination of each variable to then create a "branch" of the tree which can be used as a decision in treatment. The final model results in only those variables which are significant to outcomes. Generalized linear model (GLM) employing logistic regression and survival analysis with R software was used and the final fitting of the model was determined through the use of random forest and evolutionary tree algorithms. Individuals presenting with an [AMH] of >3.15 ng/ml and a good prognosis had a lower success per treatment (n = 11, 0% success) when total gonadotropin doses were greater than 3325 IU. Individuals that presented with an [AMH] of <1.78 ng/ml and a poor prognosis exhibited a greater success per treatment (n = 11, 80% success). AMH emerged as a superior indicator of blastocyst development compared to basal FSH. The accuracy of the prediction model, our statistical analysis using decision tree, evtree methodology is 86.5% in correctly predicting outcome based on the significant variables. The likelihood that the outcome with be incorrect of the model, or the error rate is 13.5%. CONCLUSIONS: [AMH] is a superior indicator of ovarian stimulation response and an actionable variable for stimulation dose management for optimizing blastocyst development in culture. Women whose [AMH] is ≥3.2 mg/ml, having a good prognosis, and developing >12 mature follicles result in <40% blastocysts when gonadotropin doses exceed 3325 IU per treatment. IVF treatments for poor responders that present with infertility due to diminished ovarian reserve, if managed appropriately, can produce more usable blastocyst per IVF treatment, thus increasing rate of blastocyst developmental success and ultimately increasing live birth rates. Future studies are needed to investigate the intra-follicular and the intra-cellular mechanisms that lead to the inverse relationship of blastocysts development and total gonadotropin doses in good responders in contrast to poor responders.


Anti-Mullerian Hormone/blood , Blastocyst/metabolism , Blastocyst/physiology , Embryonic Development/physiology , Follicle Stimulating Hormone/blood , Adult , Embryo Transfer/methods , Female , Fertilization in Vitro/methods , Humans , Infertility/blood , Infertility/therapy , Live Birth , Male , Ovarian Follicle/metabolism , Ovarian Reserve/physiology , Ovary/metabolism , Ovary/physiology , Ovulation Induction/methods , Pregnancy , Pregnancy Rate , Retrospective Studies
5.
Child Abuse Negl ; 92: 32-42, 2019 06.
Article En | MEDLINE | ID: mdl-30908992

BACKGROUND: Emotional abuse is a form of maltreatment that most strongly predicts adult depressive symptoms in community samples. Introject theories suggest that some depressive symptoms stem from survivors having learned to treat themselves the way they were treated by their perpetrators. OBJECTIVE: Malevolent introjects may undermine self-compassion, which may subsequently maintain feelings of shame. Thus, we hypothesized that self-compassion and shame would mediate the path from retrospective reports of maltreatment to concurrent depressive symptoms in adulthood. PARTICIPANTS AND SETTING: Participants were 244 adult community members and college students living in a Southwestern American metroplex. METHOD: We ran a multiple mediator path model with emotional abuse as the independent variable. We specified four covariates: physical abuse, sexual abuse, physical neglect, and emotional neglect, and held constant the variance they explained in self-compassion, shame, and depression. RESULTS: Our final model accounted for 53.1% of the variance in adult depressive symptoms. A significant indirect effect from emotional abuse passed through both mediators and ended in adult depressive symptoms. We also found an indirect path from emotional neglect to depression passing through both mediators. CONCLUSIONS: It appears emotional abuse and emotional neglect can undermine the formation of self-compassion. Low self-compassion predicts greater shame and depressive symptoms. Our model suggests self-compassion may be a particularly effective intervention point for survivors of emotional maltreatment.


Adult Survivors of Child Abuse/psychology , Child Abuse/psychology , Depression/psychology , Emotions , Adolescent , Adult , Aged , Child , Empathy , Female , Humans , Male , Middle Aged , Retrospective Studies , Shame , Students/psychology , Young Adult
6.
Exp Aging Res ; 43(1): 1-20, 2017.
Article En | MEDLINE | ID: mdl-28067611

Background/Study Context: This study examined the potential impact of self-reported depressive symptoms on the age-related capacity for inhibition and suppression, utilizing a negative priming paradigm. METHODS: One hundred eighty-five community-residing adults varying in age (98 younger adults, Mage = 22; 87 older adults, Mage = 69) completed a nonconscious priming task, the Geriatric Depression Scale (GDS), the White Bear Suppression Inventory (WBSI), the Depression Sensitivity Scale (DSS), a free thought suppression task, as well as several measures indexing overall cognitive ability and psychomotor speed. Hierarchical regressions investigated the interaction of depressive symptoms with age and its effect on both positive and negative priming performance, indexing both facilitation and inhibition effects, respectively. RESULTS: Results support the hypothesis that noncognitive factors affect effortful performance among older adults, although this influence varied with the specific component of the GDS, i.e., Dysphoria, Social Withdrawal, and Cognitive Control, and with the measure of depressive symptoms, i.e., GDS versus DSS. CONCLUSION: These data suggest that aging's impact on both facilitation and inhibition, e.g., positive and negative priming, are to an extent, a function of individual differences in depressive symptoms that interact with age in influencing the necessity to reallocate one's cognitive resources to deal with depressive thoughts and feelings.


Aging/psychology , Depression/diagnosis , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Cognition , Depression/psychology , Female , Geriatric Assessment/methods , Humans , Inhibition, Psychological , Male , Middle Aged , Psychiatric Status Rating Scales , Young Adult
7.
Int J Otolaryngol ; 2009: 745151, 2009.
Article En | MEDLINE | ID: mdl-20130766

Studies have shown that cigarette smoking is a risk factor for hearing loss; however, no information is available on auditory preclinical indicators in young chronic cigarette smokers. Cigarette smoking involves exposure to many harmful chemicals including carbon monoxide (CO). In this study, the CO level in 16 young normal hearing male chronic smokers was measured with a CO monitor, and was used as the outcome measure. Subjects were administered a battery of audiological tests that included behavioral and electrophysiologic measures. The goal was to investigate which auditory test measures can be used as potential predictors of the outcome measure. Using ordinary least squares estimation procedures with best-subsets selection and bootstrapped stepwise variable selection procedures, an optimal predictive multiple linear regression model was selected. Results of this approach indicated that auditory brainstem response peak V amplitudes and distortion product otoacoustic emissions had the highest predictive value and accounted for most of the variability.

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