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What causes host-use specificity in herbivorous insects? Population genetic models predict specialization when habitat preference can evolve and there is antagonistic pleiotropy at a performance-affecting locus. But empirically for herbivorous insects, host-use performance is governed by many genetic loci, and antagonistic pleiotropy seems to be rare. Here, we use individual-based quantitative genetic simulation models to investigate the role of pleiotropy in the evolution of sympatric host-use specialization when performance and preference are quantitative traits. We look first at pleiotropies affecting only host-use performance. We find that when the host environment changes slowly the evolution of host-use specialization requires levels of antagonistic pleiotropy much higher than what has been observed in nature. On the other hand, with rapid environmental change or pronounced asymmetries in productivity across host species, the evolution of host-use specialization readily occurs without pleiotropy. When pleiotropies affect preference as well as performance, even with slow environmental change and host species of equal productivity, we observe fluctuations in host-use breadth, with mean specificity increasing with the pervasiveness of antagonistic pleiotropy. So, our simulations show that pleiotropy is not necessary for specialization, although it can be sufficient, provided it is extensive or multifarious.

SUMMARY Independent assurance of extended external reports (EER) is one of the most significant trends in today’s global assurance profession. When companies decide to purchase third-party assurance on EER, they need to decide whether to engage their financial statement auditor or a different assurance provider. We examine factors that impact this decision, and the consequences of this decision on financial statement audit quality and cost. We find that independence concerns are associated with companies choosing different EER assurance providers from their incumbent financial statement auditors, while providers’ expertise in EER assurance and the recent trend of integrating nonfinancial information into the annual report promote the use of the same provider. We further find some evidence that companies with the same provider attesting to both financial statements and EER benefit from having higher financial statement audit quality without paying significantly different audit fees.

Given the political and economic conditions that Egypt is going through in particular and the region in general, we find that the movement Tourism to Egypt has been greatly affected, which in turn affected the Egyptian national income, and from here it was necessary for everyone to think, according to his specialization, in creative and innovative solutions to overcome this problem, including reliance on domestic tourism as its components are the length and width of Egypt. As well as the large Egyptian population that can be To play a major role in compensating for the shortage in foreign tourism, as well as linking Egyptians to their different environments and increasing their awareness of the Egyptian folklore in all parts of the country. Dependence on the popular heritage from construction systems to internal design supplements will greatly guide the expenses of tourism establishments, as well as relying on local operators, which will in turn reduce the reservation prices of these establishments and encourage the low-income citizen to engage in the experience of domestic tourism.

Purpose: To determine the status of sub-specialization among Nigerian ophthalmologists as well as their dispositions and barriers against sub-specialization with a view to providing valuable information for the purpose of human resources for eye care planning thereby providing useful insight into the future of ophthalmic practice in Nigeria. Methods: This was a web-based, cross-sectional study conducted among Ophthalmologists in Nigeria. An online questionnaire was distributed through e-mails using Qualtrics software (Qualtrics, Provo, UT, USA). Information concerning socio-demographic characteristics, type of practice, location of practice, years of practice, status and disposition to sub-specialization as well as barriers to sub-specialization were obtained through the questionnaire.Results: two hundred and four Nigerian Ophthalmologists participated in the study out of which 118 (57.8%) were females. One hundred and ten (54.0%) respondents had undergone sub-specialty training. The sub-specialties with the highest number of patronage was Paediatric Ophthalmology and Strabismus (14.2%). Respondents older than 46 years were three times more likely to have undergone subspecialty training compared to respondents who were aged 46 years and below [odds ratio (OR) = 3.01, 95% Confidence interval (CI) = 1.33 – 6.83, p = 0.01]. The main barriers to the availability and uptake of sub-specialty services as well as the challenges of sub-specialty services at the centres with established sub-specialty practice were non-availability/inadequate trained specialist and inadequate equipment. Conclusion: Nigerian Ophthalmologists are well disposed to sub-specialization although the extent of sub-specialization among them was a little above average. The main barriers to the availability and uptake of sub-specialty services as well as the challenges of sub-specialty services at the centres with established sub-specialty practice in this study were non-availability/inadequate trained specialist and inadequate equipment.

This paper uses the “smile curve” mapping tool with a Y-axis for value-added ratio and an X-axis for production stages to identify value-added gains, positions, and interdependencies of foreign- and domestic-owned firms in global value chains (GVCs). Taking the U.S. and China's ICT firms’ exporting activities as a target, we find that China-based domestic-owned ICT firms’ value chain appears as a smile curve differing from the U.S.-based domestic-owned ICT firms’ inverted-U curve, which reflects the considerable difference in their technical specialization in joining GVCs; foreign-owned firms are good at utilizing each country's comparative advantages and can thus arrange value chains as smile curves regardless of whether they are located in the U.S. or China; China-based domestic-owned firms have increasingly plugged into most ICT value chains. All findings reflect how “sticky” the interdependency among countries along GVCs is and can thus help understanding the impact of the U.S.–China trade war.

Birdsong is an important signal used in intra- and intersexual communication in a reproductive context. Strong sexual and natural selective forces act on this behaviour, such that singing individuals can be viewed as vocal athletes whose performance is critical for reproductive success. In this review, I argue and illustrate how a solid understanding of song production mechanisms can enhance our investigations of performance. From a production perspective, temporal and spectral features of song are relatively well understood and therefore are discussed in detail. Performance ranges of temporal and frequency characteristics can be broad, but often involve different production mechanisms, with different constraints and trade-offs underlying their generation. Based on these multifaceted features, I argue that song may be perceived as an ‘acoustic gestalt’, which for each syllable represents a specific location in a complex multidimensional parameter space characterized by differential contributions of individual features. Derived from this view, I also propose that individual males may be showing specialization for exceptional performance of some, but not all, features of song. To illustrate this possibility for a future research focus, I quantify some song features of seven male European robins, and, although the data set is limited, it shows that different individuals exhibit different performance levels across a number of song features.

Urban areas are expanding globally with far-reaching ecological consequences, including for wildlife-pathogen interactions. Wildlife show tremendous variation in their responses to urbanization; even within a single population, some individuals can specialize on urban or natural habitat types. This specialization could alter pathogen impacts on host populations via changes to wildlife movement and aggregation. Here, we build a mechanistic model to explore how habitat specialization in urban landscapes affects interactions between a mobile host population and a density-dependent specialist pathogen that confers no immunity. We model movement on a network of resource-stable urban sites and resource-fluctuating natural sites, where hosts are urban specialists, natural specialists, or generalists that use both patch types. We find that for generalists, natural and partially urban landscapes produce the highest infection prevalence and mortality, driven by high movement rates at natural sites and high densities at urban sites. However, habitat specialization protects hosts from these negative effects of partially urban landscapes by limiting movement between patch types. These findings suggest that habitat specialization can benefit populations by reducing infectious disease transmission, but by reducing movement between habitat types it could also carry the cost of reducing other movement-related ecosystem functions, such as seed dispersal and pollination.

Beetles are hosts to a remarkable diversity of bacterial symbionts. In this article, we review the role of these partnerships in promoting beetle fitness following a surge of recent studies characterizing symbiont localization and function across the Coleoptera. Symbiont contributions range from the supplementation of essential nutrients and digestive or detoxifying enzymes to the production of bioactive compounds providing defense against natural enemies. Insights on this functional diversity highlight how symbiosis can expand the host's ecological niche, but also constrain its evolutionary potential by promoting specialization. As bacterial localization can differ within and between beetle clades, we discuss how it corresponds to the microbe's beneficial role and outline the molecular and behavioral mechanisms underlying symbiont translocation and transmission by its holometabolous host. In reviewing this literature, we emphasize how the study of symbiosis can inform our understanding of the phenotypic innovations behind the evolutionary success of beetles. Expected final online publication date for the Annual Review of Entomology, Volume 67 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Identifying the target tasks of specialized learners via needs analysis (NA) is a crucial first step in language programs design. In Chile, schools that deliver vocational education and training (VET) programs in agriculture often use English language programs which are generally not designed based on the target language needs of this specialized group of students. This paper presents a needs analysis that explored the English language requirements of agricultural technicians in Chile. It also examined how these needs are perceived by actors involved in agricultural industries and actors involved in the education of this group. Using a qualitative approach, data were elicited from document analysis and interviews with five technicians at one company and five teachers at one VET school. Findings revealed that English language was necessary for technicians to carry out specific tasks. All teachers agreed that their students should be taught not only general English, but also English that is relevant to the students' interests and needs. However, the non-existence of vocational language programs makes it difficult for English teachers to teach the contents pertinent to their students’ specialization. This study contributes to an understanding of the relevance of the English language for learners in a specialized context.

The conceptual origins of ribosome specialization can be traced back to the earliest days of molecular biology. Yet, this field has only recently begun to gather momentum, with numerous studies identifying distinct heterogeneous ribosome populations across multiple species and model systems. It is proposed that some of these compositionally distinct ribosomes may be functionally specialized and able to regulate the translation of specific mRNAs. Identification and functional characterization of specialized ribosomes has the potential to elucidate a novel layer of gene expression control, at the level of translation, where the ribosome itself is a key regulatory player. In this review, we discuss different sources of ribosome heterogeneity, evidence for ribosome specialization, and also the future directions of this exciting field.

Purpose This paper aims to evaluate whether the integration of smart specialization strategies (S3) into clusters significantly impacts their efficiency for countries that still do not implement this policy. This study tests three effects: whether the kind of policies envisaged through an S3 strategy impacts cluster’s efficiency; whether this impact changes with the technological intensity of the clusters; to determine which S3 is more suitable for sub-clusters at different levels of technological intensity. Design/methodology/approach The Mexican economy is taken as case of study because it has a proper classification of its industries intro Porter’s cluster’s definition but still does not adopt the S3 policy. Through data envelopment analysis (DEA), this study evaluates the cluster’s efficiency increment when variables representing the S3 elements are included. Findings The results show that strategies following the S3 had a significant impact in all clusters, but when clusters were classified by technological intensity, the impact on efficiency is higher in clusters in the medium low-tech group. Practical implications According to the results in the DEA, it can be concluded that these S3 strategies have the potential to increase the clusters’ productivity significantly. These results make convenient the adoption of the S3 policy by countries that already count with a properly cluster definition. Originality/value These findings contribute to the lack of studies that analyze the join implementation of S3 on clusters.

In this paper, we show that trust favors specialization in complexity. U.S. states with a high level of generalized trust tend to specialize in industries involving more complex input-output relationships. This pattern is not driven by differences in the states’ other observable characteristics or unobservable time-varying industry- or state-specific factors and does not reflect selection by export destination. Although theoretical considerations suggest that trust may be endogenous to the location of complex industries, an instrumental variable strategy that leverages the impact of racial discrimination confirms that trust is a factor in the specialization of U.S. states in more complex industries.

This study investigates the value of auditor industry specialization. In the first step, we use a discrete choice model to derive the first-order demand for auditor industry specialization. Our results reveal that clients have a general preference for auditor industry specialization, relating to both audit firm and audit office specialization. We observe that specializations at the audit firm and audit office level are substitutes. We also find that larger, more complex clients have a stronger demand for industry specialization at the audit office level. In the second step, we use the results from the discrete choice model to quantify the value of auditor industry specialists for clients. We find the overall value of industry specialization aggregated across all clients is 5.2 million USD (0.36 percent of audit fees) and that industry specialization at the firm (office) level is decisive for auditor choice in 4 percent (6 percent) of all cases. JEL Classifications: M42; M48; L11; L84.

The K to 12 reform and the new Philippine Professional Standard for Teachers have changed the landscape of teacher quality requirements in the Philippines. It is in this context that this study is deemed necessary to determine the area of specialization and the teaching performance of the public secondary school Science teachers in terms of science content knowledge with this new educational schemeThere were 46 respondents in this study from the Department of Education-Guihulngan City Division, Negros Oriental Philippines. Findings reveal that the science teachers’ area of specialization can be categorized as Bachelor of Secondary Education (BSED) major in General Science, BS in Scientific Field (Nursing, Biology, and Chemical Engineering) and the Non-Science Field (English, TLE, Social Science). It indicates that majority of them lack the needed educational qualification to teach all science disciplines in the K12 curriculum. Furthermore, it shows that the BSED-General Science teachers with outstanding rating perform better than the B.S. in Scientific Field group and the non-science teachers with very good and good performance ratings respectively. It is an indication of lack of science content knowledge among the non-science teachers. Furthermore, the result discloses that the area of specialization is a determining factor in their teaching performance. It revealed that among the three groups of respondents, the general science teachers appear to be the most efficient. They are followed by those in the B.S. in Scientific field, and the non-science teachers came out to be the lowest. Hence, it clearly suggests that the BSED-General Science teachers are the most qualified to teach science since they have the sufficient educational preparations. The B.S.in Scientific Field teachers need to undergo more training and enroll in graduate studies to master all the science areas in the K12 curriculum. While the non-science teachers are discouraged to handle science subjects since they lack the necessary educational preparation to teach science.

Individual foraging specialization is a widespread occurrence and has numerous causes and consequences associated with it. However, one key area that has remained largely undiscussed, is the presence of such specialization in group-living species. This warrants special consideration as the behaviour of individuals living in groups is strongly influenced by their social environment, and so may result in distinct mechanisms favouring specialization. Here, we synthesize current theories regarding individual specialization and apply these to group-living species. In doing so we develop a set of testable predictions about the causes and consequences of individual foraging specialization in group-living species. In particular, we conclude that increased local competition between conspecifics will drive the development of individual foraging specialization in group-living species. We hypothesize that ‘one-to-one’ learning will promote individual foraging specialization, whereas learning from multiple role models will erode individual specialization through behavioural conformity. This increase in specialization may also make social groups more resilient to environmental change. We argue that testing predicted causes and consequences of individual specialization in group-living species is an important step in developing our understanding of the evolution of animal societies and how they are likely to be affected by a changing environment.

The green economy is particularly important in China's pursuit of high-quality economic growth. Adopting China's provincial balance panel data from 2000 to 2017, this article attempts to reveal the impact of polycentric agglomeration on green total factor productivity, its action path, and the synergistic effect of market integration by employing instrumental variable estimation and a mediating effect model. A significant inverted U-shaped relationship is found between polycentric agglomeration and green total factor productivity, and the polycentric agglomeration in most provinces has not exceeded the inflection point. Furthermore, the mediating effect shows that functional urban specialization and technological innovation are effective paths through which polycentric agglomeration enhances green total factor productivity. Finally, market integration contributes to green total factor productivity, and a significant positive synergistic effect exists between market integration and polycentric agglomeration. Therefore, this paper argues that China should continue to develop polycentric agglomeration and accelerate the process of market integration to promote green economic efficiency.

Previous studies indicate that adults show specialized syntactic and semantic processes in both the temporal and frontal lobes during language comprehension. Neuro-cognitive models of language development argue that this specialization appears earlier in the temporal than the frontal lobe. However, there is little evidence supporting this proposed progression. Our recently published study ( Wang, Rice, & Booth, 2020 ), using multivoxel pattern analyses, detected that children as young as 5 to 6 years old exhibit specialization and integration in the temporal lobe, but not the frontal lobe. In the current study, we used the same approach to examine semantic and syntactic specialization in children ages 7 to 8 years old. We found support for semantic specialization in the left middle temporal gyrus (MTG) for correct sentences and in the triangular part of the left inferior frontal gyrus (IFG) for incorrect sentences. We also found that the left superior temporal gyrus (STG) played an integration role and was sensitive to both semantic and syntactic processing during both correct and incorrect sentence processing. However, there was no support for syntactic specialization in 7- to 8-year-old children. As compared to our previous study on 5- to 6-year-old children, which only showed semantic specialization in the temporal lobe, the current study suggests a developmental progression to semantic specialization in the frontal lobe. This project represents an important step forward in testing neuro-cognitive models of language processing in children.

We investigate how sociology students garner recognition from niche field audiences through specialization. Our dataset comprises over 80,000 sociology-related dissertations completed at U.S. universities, as well as data on graduates’ pursuant publications. We analyze different facets of how students specialize—topic choice, focus, novelty, and consistency. To measure specialization types within a consistent methodological frame, we utilize structural topic modeling. These measures capture specialization strategies used at an early career stage. We connect them to a crucial long-term outcome in academia: becoming an advisor. Event-history models reveal that specific topic choices and novel combinations exhibit a positive influence, whereas focused theses make no substantial difference. In particular, theses related to the cultural turn, methods, or race are tied to academic careers that lead to mentorship. Thematic consistency of students’ publication track also has a strong positive effect on the chances of becoming an advisor. Yet, there are diminishing returns to consistency for highly productive scholars, adding important nuance to the well-known imperative of publish or perish in academic careers.

Smart specialization has been a central strategy for regional smart specializations (RS3s) across the European Union (EU), as a way to stimulate innovative development of the EU regions. The strategy aims to stimulate development in areas or regions that do not necessarily have the highest technological advancement but that have specialized and have had a comparative advantage to implement innovations based on research. This paper aims to initiate a discussion on the potential use of S3 as a platform for social entrepreneurship and innovation with the goal to promote and improve population health through the lens of health equity. Social entrepreneurship and innovation embedded within smart specialization presents a unique opportunity for health promotion and health equity in an agenda for regional development. However, empirical research is needed to develop new models for investigating the intersections between S3, SE and SI, and health promotion, health equity and sustainable development goal 3 (ensure healthy lives at all ages).

A presente pesquisa tem por objetivo compreender como discentes do curso de especialização em Ensino de Biologia, modalidade a distância, discutem a temática de gênero e sexualidades em sua prática docente. Para tanto, foi realizada a aplicação de questionário via Google Docs a discentes matriculados nos 8 polos que ofertam o referido curso de especialização pelo período de 18 a 25 de maio de 2019. Partimos da premissa de que a escola se constitui enquanto heteronormativa e LGBTfóbica. Além disso, o discurso biológico se configura como um regulador de práticas humanas. Desta forma, docentes da disciplina de biologia possuem um importante papel na desconstrução de práticas com enfoque no determinismo biológico para a compreensão de gênero e sexualidades, bem como no combate a preconceitos e discriminações. Os resultados evidenciam que, em sua maioria, os docentes discutem tranquilamente as temáticas, tornando-se mobilizadores neste processo de abertura para tais abordagens em âmbito educacional, mesmo com a falta de preparo e omissão por parte de outros docentes e da equipe pedagógica. Por fim, a maioria dos participantes concordam com a importância dos temas em âmbito escolar, utilizando das mais variadas metodologias e estratégias para a promoção do respeito e ao enfrentamento da LGBTfobia.

Focusing on preservice classroom teachers (PCTs) with a physical education (PE) specialization, this exploratory case study aimed at investigating the teaching quality in the lessons offered by these teachers during their field placement, as well as examining their views about teaching PE. Toward this end, seven volunteer female PCTs studying at a national university in Cyprus were recruited; all had attended three PE specialization courses before their field placement. Data were gathered through systematic observations, semi-structured interviews, and document analysis. The quantitative data were analysed using SPSS and the qualitative data using case and cross-case analysis. These analyses suggested that the PCTs could effectively employ classroom and time management as well as skill demonstration; they could also provide quality student practice. In contrast, task progression, accountability of student practice, and task explicitness appeared to be more challenging for them to successfully enact. Interestingly, their lesson plans foreshadowed how effectively most of the examined practices would be employed by the PCTs. This study contributes a new understanding of PCTs’ PE teaching during field placement and their views thereof. The implications of the findings for PCTs’ education are discussed.

Bu çalışmanın amacı, Türkiye’nin cam ve cam eşya sektöründe dış ticaret yaptığı 19 ürün grubundaki ihracat uzmanlaşma ve rekabet gücünün belirlenmesidir. Bunun için Türkiye’nin ve dünyanın, 2010-2019 yılları arası hem bu ürün gruplarındaki ihracat ve ithalat verileri hem de toplam ihracat ve ithalat verileri kullanılmıştır. Veriler, HS 2007 ürün sınıflandırması baz alınarak, UN Comtrade veri tabanından elde edilmiştir. Açıklanmış Karşılaştırmalı Üstünlükler (AKÜ) yönteminin kullanıldığı çalışmada, Nispi İhracat Avantajı (RXA), Nispi Ticaret Avantajı (RTA) ve Net İhracat İndeksi (NEI) ile analizler yapılmıştır. Cam ve cam eşya sektörü dış ticaretine yönelik 19 ürün grubu için yapılan analizlerde, ithalatın dikkate alınmadığı RXA indeksine göre, Türkiye’nin 4 ürün grubunun ihracatında, dünya ortalamasının üzerinde uzmanlaştığı belirlenmiştir. İthalatın da dikkate alındığı RTA sonucuna göre ise Türkiye 7 ürün grubunun ihracatında uzmanlaşmıştır. Ülkenin kendi ticari performansını ölçen NEI sonucuna göre ise Türkiye’nin 7 ürün grubunun ihracatında uzmanlaştığı tespit edilmiştir. Burada NEI sonuçlarına göre, Türkiye’nin ihracatında uzmanlaştığı bu 7 ürün grubu, RTA analizi sonucunda dünya ortalamasının üzerinde uzmanlaştığı ürün grupları ile aynıdır. Sonuç olarak Türkiye, cam ve cam eşya sektöründe 19 ürün grubundan 7’sinin ihracatında uzmanlaşmış ve küresel bir rekabet avantajı elde etmiştir.

SYNOPSIS We study the costs and benefits to the issuer of engaging an initial public offering (IPO) auditor specialist. We measure IPO auditor specialization and then find that IPO specialist auditors earn significant fee premiums relative to IPO auditors without specialization and that clients with an IPO specialist auditor exhibit lower levels of underpricing relative to clients without an IPO specialist auditor. We also demonstrate that IPO specialist auditors provide higher quality audits than IPO auditors without IPO audit specialization, finding that their IPO clients have a lower likelihood of financial misstatement and have lower discretionary accruals. Collectively, our results have important implications for the auditing profession and capital markets because we demonstrate empirical evidence of the costs and benefits of engaging IPO specialist auditors.

This study aimed to investigate the level of ethical sensitivity among Princess Alia University College Students in Jordan and how this is influenced by their educational level and specialization. To achieve the objects of the study, the ethical sensitivity scale questionnaire (ESSQ) was used, as developed by Narvaez (2001). This was used to measure the moral sensitivity of adults and adolescents. It consists of (28) items in seven dimensions, which are the ability to read emotions, to represent the views of others, interest in communication with others, the activation of personal relations, taking into account differences and controlling social prejudice, working to generate interpretations and alternatives, and identifying the consequences of an event and the available options. The sample of the study consisted of (126) randomly selected undergraduate and graduate students. The results of the study showed that the level of ethical sensitivity among Princess Alia University College Students was low, and there were statistically significant differences in the level of ethical sensitivity due to specialization, in favor of humanities students, as well as statistically significant differences in the level of ethical sensitivity due to the educational level, in favor of master’s students.

Individual behaviour and local context can influence the evolution of ecological interactions and how they structure into networks. In trophic interactions, consumers can increase their fitness by actively choosing resources that they are more likely to explore successfully. Mathematical modelling is often employed in theoretical studies to understand the coevolutionary dynamics between consumers and resources. However, they often disregard the individual consumer behaviour since the complexity of these systems usually requires simplifying assumptions about interaction details. Using an individual-based model, we model a community of several species that interact antagonistically. Each individual has a trait (attack or defence) that is explicitly modelled and the probability of the interaction to occur successfully increases with increased trait-matching. In addition, consumers can actively choose resources that guarantee greater fitness. We show that active consumer choice can generate coevolutionary units over time. It means that the traits of both consumers and resources converge into multiple groups with similar traits and the species interactions stay restricted to these groups over time. We also observed that network structure is more dependent on the parameter that delimits active consumer choice than on the intensity of selective pressure. Thus, our results support the idea that consumer active choice behaviour plays an important role in the ecological and evolutionary processes that structure interacting communities.

Symbiotic relationships in marine environments are not fixed and can change throughout the animal’s life. This study investigated the ontogeny of symbiosis of the spider crab Libinia ferreirae with the host medusa Lychnorhiza lucerna. We described the type of relationship, the temporal correlation among species, and food habits. More than 50% of the sampled crabs were symbionts, most in early life stages. The highest number of crabs found in a single medusa was 11. Symbiosis was observed throughout most of the year but was more evident in warm periods. The crab has many benefits in this relationship with a medusa. One is the use of food resources captured by the medusa, primarily copepods. Because the crab steals the medusa’s food, it is a kleptoparasitic relationship. There is a niche partition between symbiont and the free-living crabs as they occupy different habitats and use nonoverlapping food resources. Previous research reported that symbiosis first developed during the crab’s last larval phase (megalopa) when crab and medusa are in the same habitat. Observation of the crab’s behavior shows that symbiosis occurs when the crab can grab to the medusa when the host touches the sea bottom. The crab also took advantage of water currents, releasing itself from the substrate and then drifting toward the medusa. The symbiotic relationship that crabs have with the medusa provides then with a nursery, food resources, shelter, dispersion, and decreased competition with free-living adult crabs, all essential for the crab’s survival.

We seek to build a framework with which researchers can track the trends in charter school specialization and parents can better understand their options. This report examines the entire charter sc...

This study examines if households experience utility gains by selecting one of its members to specialize in its financial management. Utilizing data that are collected from the Health and Retirement Study, a variable measuring households’ level of financial specialization (HFS) is first constructed. The HFS variable is examined for its association with household utility, measured in this study as financial satisfaction, income satisfaction, and life satisfaction. The evidence provided strongly indicates that a household that selects one of its members to specialize in its financial management experiences utility gains.

This paper combines the semiparametric modified ordinary least-squares approach by Simar et al. (2017) with the nonparametric shape constraint regression approach by Du et al. (2013) to evaluate th...

I here review the potential effects of climate change on aphidophagous ladybirds and their future diversity. Aphidophagous ladybirds face challenges arising directly from climatic change and indirect challenges due to the effect of climate on their aphid prey and other organisms with which they interact. Ladybirds show at least some potential to respond to changes of climate through genetic change or phenotypic plasticity, notably through changes in colour pattern, dormancy and voltinism but also through thermal physiology and microhabitat or habitat plasticity. Phenological changes will likely occur in many aphidophagous species arising from relations with their prey. Changes in aphid abundance may lead to changes in ladybird prey associations over the season. The tendency to prey on multiple aphid species will insulate many ladybird predators from decline resulting from changes in the abundance of particular aphids. Like other insects, the geographic ranges of aphidophagous ladybird species will change as they track the climate. This is evidenced by the fossil record of ladybirds and by recent changes in ladybird biogeography. Such changes may be accompanied by a degree of thermal or phenological adaptation. It is likely that cold-adapted ladybirds and some island species will go extinct. Specialised species may also be threatened. A problem in assessing the threat to the latter is the minimal amount of research carried out on specialised species. In summary, aphidophagous ladybirds exhibit some potential resilience against climate change, but future climatic effects on their overall biodiversity are not fully clear.

The paper assesses gender differences in pre-labor market specialization among the college-educated and highlights how those differences have evolved over time. Women choose majors with lower potential earnings (based on male wages associated with those majors) and subsequently sort into occupations with lower potential earnings given their major choice. These differences have narrowed over time, but recent cohorts of women still choose majors and occupations with lower potential earnings. Differences in undergraduate major choice explain a substantive portion of gender wage gaps for the college-educated above and beyond simply controlling for occupation. Collectively, our results highlight the importance of understanding gender differences in the mapping between college major and occupational sorting when studying the evolution of gender differences in labor market outcomes over time.

Bush, CM, Wilhelm, AJ, Lavallee, ME, and Deitch, JR. Early sport specialization in elite weightlifters: weightlifting injury occurrence and relevant opinions. J Strength Cond Res XX(X): 000-000, 2019-Sports specialization has been associated with increased injury and burnout. This study sought to determine the age, rate of injury, influence to specialize, and opinions surrounding the impact of sports specialization in attainment of elite-level weightlifting status. A link to an anonymous survey was distributed to the top 20 weightlifters in each weight class (8 male and 7 female weight classes). The survey questioned athletes about both age and motivation to specialize, previous injuries and/or surgeries, and level of competition. Injuries and surgeries were compared between those who specialized at the Youth level (≤age 16), Junior level (ages 17-20), and nonspecialized weightlifters. One hundred forty-one athletes (47.0%) completed the survey. Sixteen participants (11.3%) specialized at the Youth level, 18 (12.8%) specialized at the Junior level, and the remaining 107 (75.9%) did not specialize before age 21. There was a statistically significant difference in the occurrence of injury before age 21 between weightlifters specializing at the Youth level and those who did not specialize (Χ(1) = 22.4, p < 0.0001). There were no statistically significant differences in serious injury after age 21 between groups. Weightlifters cited primarily themselves (45.4%) or coach (43.1%) as a driving influence to specialize. The majority of athletes (68.8%) felt that specializing during the Youth age group was not necessary to achieve elite status. Despite a relatively small sample size, injuries occurred more frequently in weightlifters specializing at younger ages, suggesting that risks associated with early sport specialization also apply to weightlifters. These risks should be considered before implementing an early specialization training regimen.

Background Youth sports participation is encouraged for proposed physical and psychological benefits. However early sport specialization and the potentially negative consequences may be a cause for concern. Purpose To describe sport specialization in Canadian youth and investigate associations with previous injury and physical performance. Study design Cross-sectional study. Methods Junior high school students (grades 7-9, ages 11-16) were invited to participate. All participants completed a questionnaire capturing specialization level (low, moderate, high; based on year-round training, exclusion of other sports, and single-sport training) and injury history in the previous 12-months. Additionally, all participants completed physical performance measures including vertical jump (cm), predicted VO2max (mL/kg/min), single-leg balance (secs) and Y-Balance composite score (%). Logistic regression examined the association between school grade, school size, sex and sport specialization (Objective 1) and the association between sport specialization and injury history (Objective 2). Multivariable linear regression analyses (4) assessed associations between sport specialization category and physical performance measures (Objective 3). Results Two hundred and thirty-eight students participated in the study. Eighteen percent of participants reported high specialization, with no significant associations between sex, grade or school size and specialization category. There was no significant difference in the odds of sustaining previous injury between participants reporting moderate (odds ratio [OR]=1.94, 95% CI 0.86-4.35) or high (OR=2.21, 95% CI 0.43-11.37) compared to low specialization. There were no significant differences in vertical jump height (mean diff [MD] = -0.4 to 2.1cm), predicted VO2max (MD = 2.2 to 3.1mL/kg/min), single leg balance (MD = 0.5 to 1.9sec) or Y-balance (MD = 0.6 to 7.0%) between sport specialization categories. Conclusions Sport specialization exists in Canadian junior high schools but may be less common than previously reported and it was not associated with sex, grade, or school size. Level of specialization was not associated with history of injury nor a range of physical performance measures. Level of Evidence Level 3

This study investigates the existence and extent of employment polarization in the Netherlands between 1999 and 2012. We first determine an asymmetrically polarized employment growth nationally and in local labor markets, especially among young workers. Second, our dynamic panel system-generalized method of moments instrumental variable approach documents that employment polarization is the combined outcome from the interplay between technology and international trade. Our analysis also uncovers novel insights considering the regional determinants of employment polarization; specifically, we demonstrate that employment growth is more likely to polarize in less densely populated regions and those with higher initial specialization in medium- and high-skilled sectors.

In a society, several individuals can help to execute a task otherwise impossible to achieve individually. However, the unnecessary interference of another individual in a solitary task could delay task execution. We studied task interference in acacia ants (Pseudomyrmex spinicola) performing a foraging task. Foraging is solitary: a single worker carries a plant-produced food body and typically stores it inside the plant domatia, but sometimes workers discard them off the tree. Acacia ants have behavioural subcastes among workers with pronounced differences in task execution. Also, task specialization increases with colony size, hence smaller colonies have less specialized individuals. Here, we first assessed whether interferences on a solitary task provided any benefit to the colony, to counteract the delay in performing the task. We found that when nestmates interfered, food items were more likely to be stored rather than discarded. Second, we tested the role of the worker's task specialization on the occurrence of interferences. Specifically, we tested whether interferences (1) are a by-product of lacking workers specialized in foraging (‘Jack-of-all-trades’ effect), or (2) depend on having experts trying to take over the task (‘expert effect’). We found partial support for the Jack-of-all-trades effect, because workers in smaller colonies were more often interfered with, but interferences lasted longer in medium-sized colonies; in larger colonies, workers had fewer interferences that resolved faster. Our evidence supports the ‘expert effect’, as experienced foragers had fewer and shorter interferences than workers not regularly foraging. Interfering in a solitary task in social insects parallels task conflicts and managerial issues in human organizations and may function as a quality control mechanism in a leaderless organization.

The study aimed to identify the appropriateness of the science teacher's specialization path in the intermediate stage in Saudi Arabia for teaching science courses and the difficulties of implementation from the point of view of teachers in Tabuk. The study used the descriptive method, and a questionnaire surveyed the opinions of teachers. It was distributed to a sample of (41) middle school science teachers in public schools in the city of Tabuk. The results of the study showed that the reality of the appropriateness of the science teacher's specialization path in the intermediate stage for teaching science courses obtained an overall average of (4.18). Or by (83.6%) and reflects the appropriateness of (weakly), and it also revealed difficulties that hinder the appropriateness of science books from the teachers’ point of view with a total average (4.18 from 5), a degree (highly), and at the level of sub-specialties, physics got the highest average (4.20). Then chemistry with an average of (4.19) and finally biology with an average of (4.14), all of which are difficulties with a degree of (highly), meaning that the contents of science courses do not fit with the course of their specialization , also there is no statistical significant differences between the teachers’ responses on the scale of the appropriateness of the science teacher’s specialization path to the scientific subject content of the science book at the intermediate stage , the study recommended the need to re-planning and implementing the science method in proportion to the method of separate subjects, and to reconsider the plans of preparation of science teachers in Saudi universities.

Across a range of youth sport contexts, early specialization (i.e., intensive engagement in a single sport from an early age) has been associated with a variety of negative outcomes such as burnout...

Purpose Sustainability assurance services are carried out in a competitive market where a wide range of assurance providers operate without the need for any specific professional qualifications, competencies or skills. Assurance providers have heterogeneous professional backgrounds and experiences that lead to substantial diversity in sustainability assurance quality levels. This paper aims to provide an understanding of sustainability assurance quality. From a legitimacy perspective, the authors focus on the choice of assurance providers by exploring why a company voluntarily chooses an incumbent financial auditor to jointly provide audit and sustainability assurance services. The authors argue that to avoid the legitimacy threats undermining stakeholders’ confidence in the sustainability information disclosed, companies should only choose their incumbent financial auditors to provide sustainability assurance services when these auditors possess the professional attributes associated with sustainability assurance quality. Design/methodology/approach This study develops regression models for an international sample for 2007–2016, where the authors analyze why a company voluntarily chooses an incumbent auditor to jointly provide audit and sustainability assurance services from a legitimacy theory perspective. Findings Evidence confirms that the choice of incumbent auditors as assurance providers is more likely when these providers are more specialized in the industry. The authors also find that independence does not play a significant role in this decision. Therefore, an assurance provider’s industry specialization can be understood as an attribute that is associated with sustainability assurance quality and one which limits the legitimacy threats caused by a lack of sufficient sustainability knowledge. Practical implications Given that companies have complete freedom when choosing their assurance providers, the selection of a high-quality incumbent auditor is an indirect measure of social commitment and a mechanism to improve public trust. The results confirm that it is fundamental for firms to understand the situations when choosing an incumbent financial auditor to provide sustainability assurance services is the best way to ensure firm legitimacy while obtaining higher sustainability assurance quality due to the spillover effect. This paper provides useful evidence for firms and managers who can become aware that the legitimacy threat associated with the auditing profession’s questionable competence to conduct efficient sustainability assurance engagements can be reduced if they hire an incumbent financial auditor with greater industry specialization. For assurance providers, the results are especially useful, as they should know that companies will be more likely to choose their incumbent financial auditor when that auditor possesses certain professional attributes, like industry specialization. The ability to assimilate and exploit the knowledge gained through auditing activities can be improved even more by specialization, which enhances sustainability assurance quality. Social implications From a social perspective, stakeholders perceive industry specialization as an indicator of the professional skills necessary to increase both the real and perceived quality of sustainability assurance services, thereby limiting the legitimacy threat arising from a lack of sustainability knowledge. The evidence also provides valuable results for regulatory bodies, as it shows that firms are not able to address the legitimacy gap caused by stakeholders’ perceptions that incumbent financial auditors can easily be controlled by companies. Thus, doubts arise as to whether this joint provision undermines auditor independence. Precisely, these doubts about assurance provider independence can erode public confidence in assurance and devalue the quality of the service. The results of this paper highlight the need to strengthen regulation on sustainability reporting and assurance. The advances and relevance of sustainable development in recent years and in future agendas require a firm commitment to sustainability reporting and assurance of quality, reliability, integrity and confidence. Originality/value First, this study contributes to recent empirical studies that focus on the role of sustainability assurance services in the legitimation process of corporate sustainability reporting. However, while that research analyzes how the legitimacy theory explains the voluntary adoption of sustainability assurance, this paper adds to the literature by presenting evidence about why certain incumbent auditors are appointed to carry out sustainability assurance services. Second, this paper contributes to the sustainability assurance quality literature. Third, unlike previous studies that have regressed various client-specific and institutional factors that influence firms’ decisions to choose assurance providers, this study contributes to the research by providing knowledge about a set of professional features that may explain the decision model of assurance providers selection from a legitimacy perspective.

We analyse how women’s participation in the labour market is influenced by their partner’s resources in Mexico. Theory predicts opposing partner effects: specialization and bargaining theory predic...

The article analyzes the activities of regional Internet companies offering books in Siberia and the Far East. The research methodology is based on the combination of comparative-typological analysis and landscape-reconstructing approach. Use is made of monitoring results of bookselling enterprises in the region within the framework of the federal project “Cultural Map of Russia”. It is shown that online sales are a dynamically developing channel of the traditional (printed) retail book market in Russia. Based on the identification and analysis of the main characteristics of enterprises offering books on the Internet (location, subject of the Russian federation, assortment, degree of integration, structure of the enterprise, etc.), the most common groups of enterprises in the regional book market are identified: internet divisions of publishing houses; multi-profile online stores; online book stores without retail divisions; online stores of bookselling enterprises. As the most common type in the regional market, the Internet divisions of wholesale and retail independent and online bookselling enterprises are identified. The features of the presentation of a specialized book on the Internet are revealed. The main areas of specialization of federal, regional and local companies offering book products on the Internet along with other products are identified: educational and office supplies, educational games and toys, business and technical literature, etc. The trends and promising directions of development of the regional online book trade are revealed. Diversification of activities and multichannel are defined as the key trend in the development of the regional book market.

Using panel data on small, open economies, this paper analyses the effect of trade liberalization on economic growth, placing a particular focus on the mechanisms that can potentially explain the estimated effects. I categorize the countries into four different sub-groups based on their predominant exports (agriculture, manufacturing, mining, and services), to identify the subgroup of countries that have benefitted the most from trade liberalization. Based on the comparative case studies employed using the synthetic control method, it is evident that the sub-group of countries with a primary focus on manufacturing exports have experienced the highest benefits overall from trade liberalization. Resource-rich economies appear to have benefitted least from opening their economy. Findings also suggest that the group of countries that have performed well (i.e. manufacturing-oriented countries) also experience significant increases in manufacturing exports post-liberalization. Results remain robust to various tests employed.

Construction product platforms provide the opportunity to improve productivity in construction projects while maintaining heterogeneity of output. The growing literature on construction product pla...

Subject. This article deals with the problems of development of promising sectors of the region's economy. Objectives. The article aims to assess the scenarios of regional industry changes considering a case study of the automotive industry. Methods. For the study, we used the bootstrap and wavelet transform techniques. Results. The article describes the inertial, pessimistic (5% percentile) and optimistic (95% percentile) scenarios for the development of the automotive industry and shows the range of possible deviations of industry dynamics in the case of the influence of external and internal factors. Conclusions. The proposed methodology and tools make it possible to fine-tune the forecast of industry dynamics, take into account its possible deviations from a predetermined path during the year, and put management decisions into proactive impact effect.