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While it is commonly assumed that farmers have higher, and foragers lower, fertility compared to populations practicing other forms of subsistence, robust supportive evidence is lacking. We tested whether subsistence activities-incorporating market integration-are associated with fertility in 10,250 women from 27 small-scale societies and found considerable variation in fertility. This variation did not align with group-level subsistence typologies. Societies labeled as "farmers" did not have higher fertility than others, while "foragers" did not have lower fertility. However, at the individual level, we found strong evidence that fertility was positively associated with farming and moderate evidence of a negative relationship between foraging and fertility. Markers of market integration were strongly negatively correlated with fertility. Despite strong cross-cultural evidence, these relationships were not consistent in all populations, highlighting the importance of the socioecological context, which likely influences the diverse mechanisms driving the relationship between fertility and subsistence., Competing Interests: Competing interests statement:The authors declare no competing interest.This article is a PNAS Direct Submission. J.H.J. is a guest editor invited by the Editorial Board.

Contemporary inequality exists at an unprecedented scale. Social scientists have emphasized the role played by material wealth in driving its escalation. Evolutionary anthropologists understand the drive to accumulate material wealth as one that is coupled ultimately to increasing reproductive success. Owing to biological caps on reproduction for women, the efficiency of this conversion can differ by gender, with implications for understanding the evolution of gender disparities in resource accumulation. Efficiency also differs according to the type of resources used to support reproductive success. In this paper, we review evolutionary explanations of gender disparities in resources and investigate empirical evidence to support or refute those explanations among matrilineal and patrilineal subpopulations of ethnic Chinese Mosuo, who share an ethnolinguistic identity, but differ strikingly in terms of institutions and norms surrounding kinship and gender. We find that gender differentially predicts income and educational attainment. Men were more likely to report income than women; amounts earned were higher for men overall, but the difference between men and women was minimal under matriliny. Men reported higher levels of educational attainment than women, unexpectedly more so in matrilineal contexts. The results reveal nuances in how biology and cultural institutions affect gender disparities in wealth. This article is part of the theme issue 'Evolutionary ecology of inequality'.

To address claims of human exceptionalism, we determine where humans fit within the greater mammalian distribution of reproductive inequality. We show that humans exhibit lower reproductive skew (i.e., inequality in the number of surviving offspring) among males and smaller sex differences in reproductive skew than most other mammals, while nevertheless falling within the mammalian range. Additionally, female reproductive skew is higher in polygynous human populations than in polygynous nonhumans mammals on average. This patterning of skew can be attributed in part to the prevalence of monogamy in humans compared to the predominance of polygyny in nonhuman mammals, to the limited degree of polygyny in the human societies that practice it, and to the importance of unequally held rival resources to women's fitness. The muted reproductive inequality observed in humans appears to be linked to several unusual characteristics of our species-including high levels of cooperation among males, high dependence on unequally held rival resources, complementarities between maternal and paternal investment, as well as social and legal institutions that enforce monogamous norms.

Cooperative networks are essential features of human society. Evolutionary theory hypothesizes that networks are used differently by men and women, yet the bulk of evidence supporting this hypothesis is based on studies conducted in a limited range of contexts and on few domains of cooperation. In this paper, we compare individual-level cooperative networks from two communities in Southwest China that differ systematically in kinship norms and institutions-one matrilineal and one patrilineal-while sharing an ethnic identity. Specifically, we investigate whether network structures differ based on prevailing kinship norms and type of gendered cooperative activity, one woman-centred (preparation of community meals) and one man-centred (farm equipment lending). Our descriptive results show a mixture of 'feminine' and 'masculine' features in all four networks. The matrilineal meals network stands out in terms of high degree skew. Exponential random graph models reveal a stronger role for geographical proximity in patriliny and a limited role of affinal relatedness across all networks. Our results point to the need to consider domains of cooperative activity alongside gender and cultural context to fully understand variation in how women and men leverage social relationships toward different ends. This article is part of the theme issue 'Cooperation among women: evolutionary and cross-cultural perspectives'.

Increased access to defensible material wealth is hypothesised to escalate inequality. Market integration, which creates novel opportunities in cash economies, provides a means of testing this hypothesis. Using demographic data collected from 505 households among the matrilineal and patrilineal Mosuo in 2017, we test whether market integration is associated with increased material wealth, whether increased material wealth is associated with wealth inequality, and whether being in a matrilineal vs. patrilineal kinship system alters the relationship between wealth and inequality. We find evidence that market integration, measured as distance to the nearest source of tourism and primary source of household income, is associated with increased household income and 'modern' asset value. Both village-level market integration and mean asset value were associated negatively, rather than positively, with inequality, contrary to predictions. Finally, income, modern wealth and inequality were higher in matrilineal communities that were located closer to the centre of tourism and where tourism has long provided a relatively stable source of income. However, we also observed exacerbated inequality with increasing farm animal value in patriliny. We conclude that the forces affecting wealth and inequality depend on local context and that the importance of local institutions is obscured by aggregate statistics drawn from modern nation states., Competing Interests: None., (© The Author(s) 2022.)

Women experience higher morbidity than men, despite living longer. This is often attributed to biological differences between the sexes; however, the majority of societies in which these disparities are observed exhibit gender norms that favor men. We tested the hypothesis that female-biased gender norms ameliorate gender disparities in health by comparing gender differences in inflammation and hypertension among the matrilineal and patrilineal Mosuo of China. Widely reported gender disparities in health were reversed among matrilineal Mosuo compared with patrilineal Mosuo, due to substantial improvements in women's health, with no concomitant detrimental effects on men. These findings offer evidence that gender norms limiting women's autonomy and biasing inheritance toward men adversely affect the health of women, increasing women's risk for chronic diseases with tremendous global health impact., Competing Interests: The authors declare no competing interest.

Background: Human populations native to high altitude exhibit numerous genetic adaptations to hypobaric hypoxia. Among Tibetan plateau peoples, these include increased vasodilation and uncoupling of erythropoiesis from hypoxia., Objective/methods: We tested the hypothesis that these high-altitude adaptations reduce risk for hypertension and diabetes-associated anemia among the Mosuo, a Tibetan-descended population in the mountains of Southwest China that is experiencing rapid economic change and increased chronic disease risk., Results: Hypertension was substantially less common among Mosuo than low-altitude Han populations, and models fit to the Han predicted higher probability of hypertension than models fit to the Mosuo. Diabetes was positively associated with anemia among the Han, but not the Mosuo., Conclusion: The Mosuo have lower risk for hypertension and diabetes-associated anemia than the Han, supporting the hypothesis that high-altitude adaptations affecting blood and circulation intersect with chronic disease processes to lower risk for these outcomes. As chronic diseases continue to grow as global health concerns, it is important to investigate how they may be affected by local genetic adaptations., (© 2020 Wiley Periodicals, Inc.)

The present study examined the impact of sleep, stress, and negative activating emotions of high-school teachers on their students' affective experience, academic motivation, and in-class satisfaction. It is hypothesized that teachers' sleep quality and stress have a positive influence on their own nervousness and irritability. With reference to the emotional crossover theory, teachers' nervousness and irritability are hypothesized to intensify students' nervousness and irritability and subsequently dampen their academic motivation and in-class satisfaction. Experience-sampling data were collected from 17 teachers and 437 students from two local high schools in Hong Kong across a 10-school-day period. Multilevel path analysis results revealed that teachers' stress was significantly associated with teachers' nervousness and irritability. Teachers' nervousness, rather than irritability, was subsequently associated with higher levels of nervousness and irritability among students, which, in turn, impaired their in-class satisfaction. There was also a significant negative association between students' irritability and their academic motivation. Results further showed that teachers' stress arising from poor sleep quality was a significant antecedent of the teacher-student emotional crossover, subsequently affecting students' academic motivation and in-class satisfaction. The findings highlight the detrimental effects of teachers' poor sleep and the resulting stress on students' academic and affective experience. Discussion focuses on how to improve teachers' sleep and manage their stress so as to enhance students' in-class emotions and academic motivation., (© 2019 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.)

Mixed-function amine oxidase (EC 1.14.13.8) has been demonstrated in highly purified rat hepatocyte nuclear envelope . The enzyme was present in the nuclear envelope at a level 20 percent of that observed in microsomes. Induction studies indicated that nuclear envelope amine oxidase as well as its microsomal counterpart were refractory to the effects of phenobarbital and 3-methylcholanthrene. Phenobarbital administration increased the specific activity of the microsomal N, N-dimethylaniline N-demethylase and benzo[a]pyrene hydroxylase by 600 and 190 percent, respectively, but decreased the specific activity of the nuclear enzymes by 30-50 percent. In contrast, 3-methylcholanthrene increased the specific activity of benzo[a]pyrene hydroxylase in nuclear envelope and microsomes by 42- and 11-fold, respectively. The hydrocarbon also increased the microsomal and nuclear N, N-dimethylaniline N-demethylase by 40 and 60 percent, respectively, but the specific activity of microsomal and nuclear aniline 4-hydroxylase was decreased by 50 percent. Demonstration of amine oxidase in rat hepatocyte nuclear envelope implicates this enzyme in the toxicity and carcinogenicity of certain drugs and chemicals.

Novel [(arylcarbonyl)oxy]propanolamines were synthesized and investigated as potential ultrashort-acting beta-adrenergic receptor blockers. Many of these analogues exhibited good potency and short duration. The N-ureidoalkyl analogue 85 (ACC-9089) has a potency equal to propranolol and a duration of action of about 21 min in the dog. It has been selected as a candidate for further clinical study. Structure-activity relationships and structure-duration relationships for these new beta-blockers are also discussed.

beta-Adrenergic blocking agents--esmolol hydrochloride, pharmacokinetic profile, metabolism. Pharmacokinetic profile--cardioselective beta-adrenergic blocking agent, methyl 3-[4-(2-hydroxy-3-(isopropylamino)propoxy]phenylpropionate hydrochloride. Esmolol--cardioselective beta-adrenergic blocking agent, pharmacokinetic profile.

The metabolism of 1-amphetamine in rabbit liver is complex in that several routes may give rise to the same intermediate. In this study, the subsequent metabolism of the primary products of N- and C-oxidation were blocked by selecting appropriate incubation conditions. The resulting simplified system was used to investigate the enzymes involved in the two pathways. Phenobarbital treatment increased N- and C-hydroxylation, whereas 3-methylcholanthrene treatment had an inhibitory effect on both pathways. Inhibitors of cytochrome P-450 were either nonselective or were partially selective in inhibiting the two routes of amphetamine metabolism. Induction modulated the sensitivity toward the inhibitors of N- and C-oxidation.

Esmolol is an ultra-short-acting beta blocker. Its kinetics was studied in eight healthy subjects after continuous intravenous infusion of 400 micrograms/kg/min over 2 hr. The concentrations of esmolol and its major metabolite, 3-[4-(2-hydroxy-3-[isopropylamino]propoxy)phenyl]propionic acid, in blood and urine were determined by gas chromatographic-mass spectrometric assay and HPLC. The distribution and elimination t1/2s of esmolol averaged 2.03 and 9.19 min. The apparent volume of distribution of esmolol averaged 3.43 l/kg and was four times the volume of the central compartment. The total clearance of esmolol averaged 285 ml/min/kg, indicating that nonhepatic routes play a predominant role in its clearance. The t1/2s of formation and elimination of the metabolite averaged 2.82 min and 3.72 hr. The ratio of the metabolite formation and elimination rate constants of the parent drug (kf/k10) averaged 0.829, suggesting that 82.9% of esmolol was converted to the metabolite (which is consistent with the urinary recovery of 71% of the dose as unconjugated metabolite). The volume of distribution and total clearance of the metabolite averaged 0.411 l/kg and 1.28 ml/min/kg. Esmolol was followed by a significant reduction of isoproterenol-induced increase in heart rate and systolic blood pressure at doses of 50, 150, and 400 micrograms/kg/min.(ABSTRACT TRUNCATED AT 250 WORDS)

Esmolol is an ultra-short-acting beta-blocker currently in Phase II clinical trials. The ester functionality in esmolol results in rapid metabolism of the beta-blocker into an acidic metabolite and methanol. Dichloromethane was used to denature blood esterases and quantitatively extract esmolol from the blood. A deuterated analogue of esmolol was selected as the internal standard, and both compounds were chromatographed as the trimethylsilyl derivatives. Blood levels of esmolol were quantitated by gas chromatography-mass spectrometry with selective-ion monitoring, focusing on specific ions corresponding to esmolol and the internal standard. The lower limit of sensitivity of the assay was 2.5 ng/mL. Using the assay, blood samples from a dose-ranging study in humans were analyzed for concentrations of esmolol. Steady-state blood levels of esmolol after intravenous infusion rates of 40, 100, 200, 300, 450, and 650 micrograms/kg/min were 0.202, 0.464, 0.977, 1.31, 1.92, and 2.97 micrograms/mL of blood. The elimination t1/2 and total body clearance were estimated to be approximately 10 min and 220 mL/kg/min, respectively. The high clearance of esmolol suggested that metabolism by blood esterase(s) was the primary determinant of the duration of action of the drug.

Hydroxyethyl starch (HES) found in rat serum and spleen after single and daily administrations of 0.9 g/kg for 1 week was characterized by gas-liquid chromatography. There was very little difference in the degree of substitution (D.S.) and molar substitution (M.S.) of HES in serum samples obtained at 1 hour and 57 days after multiple doses and of HES in spleen samples obtained at 1 hour and 168 days after a single dose of HES. The small increase in D.S. and M.S. was due to a decrease in the glucose content and not due to a change in the ratio of mono- to poly-substituted glucoses.

The reduction of N-hydroxyphentermine was studied in liver microsomes isolated from rat, guinea pig, and rabbit. The reduction requires a NADPH-generating system and was inhibited by oxygen and carbon monoxide. In the rat, the reduction was increased by phenobarbital pretreatment. Kinetic analysis of the reductase activity in rat liver microsomes suggests that the reduction of the hydroxylamine is mediated by at least two enzyme systems, one of which is a CO-sensitive system inducible by phenobarbital.

N-Hydroxyphentermine is oxidized to 2-methyl-2-nitro-1-phenylpropane by rat liver microsome preparations. This oxidation accounts for differences noted in levels of N-hydroxyphentermine formed from phentermine in washed and unwashed microsome preparations. The reaction is inhibited by hemoglobin and catalase, whose presence in unwashed microsomes could terminate the N-oxidation of phentermine at the hydroxylamine level. The hydroxylamine-nitro-oxidation appears to be dependent on cytochrome P-450, as the reaction was induced by phenobarbital pretreatment and inhibited by carbon monoxide and 2,4-dichloro-6-phenylphenoxyethylamine.

To determine the elimination of high-molecular-weight hydroxyethyl starch (HES, Mw 450,000) in normal subjects, ten volunteers were given 500 ml 6% HES solution by intravenous infusion, and serial blood and urine samples were collected for nonglucose total carbohydrate determination. On the average, 46 and 64 per cent of the dose was excreted in the urine within two and eight days, respectively. The plasma concentration declined rapidly during the first week after infusion. The average terminal half-life was 17 days during the first 42 days, which accounted for elimination of about 90 per cent of the dose. The remainder was eliminated with a terminal half-life of 48 days determined between days 42 and 83 of the study. As expected, the infusion of HES resulted in plasma volume expansion over a 48-hour period during which time levels of nonglucose carbohydrates were above 3.5 mg/ml. HES is metabolized by alpha-amylase in the body. During the first 48 hours after infusion of HES, plasma alpha-amylase activity was significantly increased over control. Concomitantly, alpha-amylase activity in urine was also elevated but not significantly so.

The extent of biliary excretion of hydroxyethyl starch (HES) in man after intravenous administration of 500 ml of a 6% solution to nine healthy male volunteers was determined using a specific gas chromatograph mass spectrometer selected ion monitoring procedure. On the average, less than 1% of the administered dose was recovered in feces over a 14 day period.