Comment on: The Vitamin D⁻Folate Hypothesis as an Evolutionary Model for Skin Pigmentation: An Update and Integration of Current Ideas, Nutrients 2018, 10, 554.

In response to a recent article by Jones et al. (Nutrients 10: 554⁻568, 2018) [1], we agree that three distinctive features evolved in Homo erectus prior to the emergence of modern humans.[...]

Bridging the Gap: 21st Century Media Meets Theoretical Pedagogical Literacy Practices

In this chapter, the researchers used an ethnographic stance to demonstrate how conversation evolved within a social media platform. They investigated the online discussions and face-to-face dialogues between teacher educators and pre-service teachers. They compared the participants’ reciprocal conversations within this case study to analyze patterns in the language used in each forum in order to identify the affordances and constraints of perceived understanding. Through this discourse analysis the authors sought to identify indicators of each participant’s metacognitive development while engaging in an online book discussion through a social media platform. Data analysis indicated that there was metacognitive growth when comparing the initial reciprocal conversations with the final conversations

\u3ci\u3eHippodamia Variegata\u3c/i\u3e (Goeze) (Coleoptera: Coccinellidae) Detected in Michigan Soybean Fields

Since its initial detection near Montreal, Canada in 1984, the variegated lady beetle Hippodamia variegata (Goeze) (Coleoptera:Coccinellidae) has spread throughout the northeastern United States. In 2005, this immigrant Old World species was detected in Michigan for the first time. Twenty-nine adults were found in soybean fields in 4 counties: Ingham, Gratiot, Kalamazoo, and Saginaw.The first individuals were found in Gratiot County on 22 June 2005; we continued to detect individuals until 18 Aug 2005 (2 individuals collected in Saginaw Co.) when sampling ended. Prior to this study, H. variegata had not been known to prey on the soybean aphid, Aphis glycines Matsumura (Homoptera: Aphididae). The establishment of soybean aphid throughout the north-central U.S. may aid the spread of H. variegata throughout the region

Information, incentives, and commitment : an empirical analysis of contracts between government and state enterprises

The authors analyze experience with written performance contracts between developing country governments and the managers of their state-owned enterprises. Such contracts have been a vogue since the mid-1980s, and substantial resources have been sunk into their design and enforcement, yet the few assessments to date show mixed results. Using a simple agency model, they identify how problems of weak incentives sthemming from information asymmetry, lack of government commitment, and lack of managerial commitment can lead to shirking. They apply the model to a sample of 12 contracts with monopoly enterprises in six developing countries (Ghana, India, the Republic of Korea, Mexico, the Philippines, and Senegal). All suffer from serious contracting problems. They find no pattern of improved performance that can be attributed to the contracts. Only three of the 12 case-study companies showed a turnaround in total factor productivity after contracts were introduced, six continued past trends, and three performed substantially worse under contracts than they had before. Labor productivity improved at a faster pace in four cases, and deteriorated in none, but the improvement predated the contract. Performance contracting assumes that government's objectives can be maximized, and performance improved, by setting targets that take into account the constraints placed on managers. For this to occur, the principals must be willing to explicitly state their objectives, assign to them priorities and weights, translate them into performance improvement targets, provide incentives to meet those targets (or monitor the agents without incurring significant costs), and credibly signal their commitment to the contract. These conditions failed to materialize. Why would governments adopt contracts to which they were notcommitted or that were politically unrealistic? Sometimes because it enabled themto get foreign assistance. How explain the managers'lack of commitment? Not surprisingly, managers with information advantages and bargaining power, and with no strong incentives or commitment from the government, used their advantages to manipulate the targets so as to ensure that their performance would be judged satisfactory. The authors outline the conditions under which performance contracts might succeed in improving performance.Environmental Economics&Policies,Labor Policies,Health Economics&Finance,International Terrorism&Counterterrorism,Banks&Banking Reform,Knowledge Economy,Health Economics&Finance,Environmental Economics&Policies,National Governance,Education for the Knowledge Economy

630-mV open circuit voltage, 12% efficient n-Si liquid junction

We report the first experimental observation of a semiconductor/liquid junction whose open circuit voltage Voc is controlled by bulk diffusion/recombination processes. Variation in temperature, minority-carrier diffusion length, and/or in majority-carrier concentration produces changes in the Voc of the n-Si/CH3OH interface in accord with bulk recombination/diffusion theory. Under AM2 irradiation conditions, the extrapolated intercept at 0 K of Voc vs T plots yields activation energies for the dominant recombination process of 1.1–1.2 eV, in accord with the 1.12-eV band gap of Si. A crucial factor in achieving optimum performance of the n-Si/CH3OH interface is assigned to photoelectrochemical oxide formation, which passivates surface recombination sites at the n-Si/CH3OH interface and minimizes deleterious effects of pinning of the Fermi level at the Si/CH3OH junction. Controlled Si oxide growth, combined with optimization of bulk crystal parameters in accord with diffusion theory, is found to yield improved photoelectrode output parameters, with 12.0±1.5% AM2 efficiencies and AM1 Voc values of 632–640 mV for 0.2-Ω cm Si materials

Culture Change in Nursing Homes: How Far Have We Come?

Presents findings from the Commonwealth Fund 2007 National Survey of Nursing Homes on the extent to which nursing homes have adopted the principles of culture change and are delivering resident-centered care, as well as the benefits the changes have brou

Reforming the urban water system in Santiago, Chile

In the late 1980s, Chile planned to privatize Santiago's sanitary works enterprise (EMOS) but instead reformed it under public ownership. It did so through a regulatory framework that mimicked the design of a concession with a private utility, setting tariffs that ensured at least a seven percent return on assets, creating a neutral regulator independent of ministry intervention, and giving EMOS the right to appeal the regulator's tariff decisions. This reform of Santiago's water system is often cited as a case of successful reform under public management. Comparing a comprehensive measure of welfare with a counterfactual example, the authors show surprisingly large gains from Santiago's reform, given the relatively good initial conditions. (The gains accrued largely to government and employees, but consumers benefited from improved service and coverage). Why did reform in Santiago improve water system performance, when similar reform attempts under public management in other countries failed? 1) Chile has a long tradition of private water rights, shaped by early recognition that water is a scarce and tradable private good. 2) The reformed regulatory framework was designed to attract private investors to the water system and to motivate them to operate efficiently and expand the system. 3) Chile's unique electoral institutions sustained this framework under state operation after democracy was restored. 4) Chile's strong bureaucratic norms and institutions (permitting little corruption), combined with Santiago's relatively low-cost water system, permitted prices that effectively increased quasi-rents for investing in the system while minimizing the risk of inefficiency or monopoly rents. The authors also address the question of why EMOS was reformed but not privatized, and what the costs of not privatizing were. The system was privatized in 1999, but the changes from privatization are likely to be less significant than those introduced in 1989-90.Decentralization,Water Conservation,Environmental Economics&Policies,Water and Industry,Water Supply and Systems,Water Supply and Sanitation Governance and Institutions,Water and Industry,Water Conservation,Environmental Economics&Policies,Town Water Supply and Sanitation

Assessing the impact of education and marriage on labor market exit decisions of women

During the late 1990s, the convergence of women's labor force participation rates to men's rates came to a halt. This paper explores the degree to which the role of education and marriage in women's labor supply decisions also changed over this time period. Specifically, this paper investigates women's decisions to exit the labor market upon the birth of a child. The results indicate that changing exit behavior among married, educated women at this period in their lives was not likely the driving force behind the aggregate changes seen in labor force participation. Rather, changes in exit rates among single women, particularly those less educated, are much more consistent with the changing pattern of aggregate female labor force participation.

To work or not to work: the economics of a mother's dilemma

Utilizing linked vital statistics, administrative employer, and state welfare records, the analysis in this paper investigates the determinants of a woman's intermittent labor force decision at the time of a major life event: the birth of a child. The results indicate that both direct and opportunity labor market costs of exiting the workforce figure significantly into that decision. Further, the analysis reveals the importance of including information about the mother's prebirth job when making inferences about the role various demographics play in the intermittent labor force decision.

Relationship between obstructive sleep apnea severity and sleep, depression and anxiety symptoms in newly-diagnosed patients.

Obstructive sleep apnea (OSA) occurs in at least 10% of the population, and leads to higher morbidity and mortality; however, relationships between OSA severity and sleep or psychological symptoms are unclear. Existing studies include samples with wide-ranging comorbidities, so we assessed relationships between severity of OSA and common sleep and psychological disturbances in recently diagnosed OSA patients with minimal co-morbidities. We studied 49 newly diagnosed, untreated OSA patients without major co-morbidities such as mental illness, cardiovascular disease, or stroke; subjects were not using psychoactive medications or tobacco (mean +/- std age: 46.8+/-9.1 years; apnea/hyponea index [AHI]: 32.1+/-20.5 events/hour; female/male: 12/37; weight <125 kg). We evaluated relationships between the AHI and daytime sleepiness (Epworth Sleepiness Scale; ESS), sleep quality (Pittsburg Sleep Quality Index; PSQI), depressive symptoms (Beck Depression Inventory-II; BDI), and anxiety symptoms (Beck Anxiety Inventory; BAI), as well as sex and body mass index (BMI). AHI was similar in females and males. Mean levels of all symptoms were above normal thresholds, but AHI was not correlated with age, ESS, PSQI, BDI, or BAI; only BMI was correlated with OSA severity. No differences in mean AHI appeared when subjects were grouped by normal versus elevated values of ESS, PSQI, BDI, or BAI. Consistent with other studies, a strong link between OSA severity and psychological symptoms did not appear in these newly diagnosed patients, suggesting that mechanisms additional to the number and frequency of hypoxic events and arousals occurring with apneas contribute to adverse health effects in OSA. OSA patients presenting with mild or moderate severity, and no major co-morbidities will not necessarily have low levels of sleep or psychological disturbances