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1.
Annu Rev Genet ; 50: 133-154, 2016 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-27617970

RESUMO

The life cycles of eukaryotes alternate between haploid and diploid phases, which are initiated by meiosis and gamete fusion, respectively. In both ascomycete and basidiomycete fungi and chlorophyte algae, the haploid-to-diploid transition is regulated by a pair of paralogous homeodomain protein encoding genes. That a common genetic program controls the haploid-to-diploid transition in phylogenetically disparate eukaryotic lineages suggests this may be the ancestral function for homeodomain proteins. Multicellularity has evolved independently in many eukaryotic lineages in either one or both phases of the life cycle. Organisms, such as land plants, exhibiting a life cycle whereby multicellular bodies develop in both the haploid and diploid phases are often referred to as possessing an alternation of generations. We review recent progress on understanding the genetic basis for the land plant alternation of generations and highlight the roles that homeodomain-encoding genes may have played in the evolution of complex multicellularity in this lineage.


Assuntos
Evolução Biológica , Plantas/genética , Briófitas/genética , Clorófitas/genética , Diploide , Eucariotos , Fungos/genética , Haploidia , Proteínas de Homeodomínio/genética , Magnoliopsida/genética , Phaeophyceae/genética , Filogenia , Rodófitas/genética
2.
Proc Biol Sci ; 291(2016): 20232351, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38351800

RESUMO

In bryophytes that alternate between haploid gametophytes and diploid sporophytes through sexual reproduction, sporophytes are often attached to and nurtured on the female gametophyte. A similar phenomenon is seen in Florideophyceae (a group of red algae). These systems in which a gametophyte (mother) invests nutrients in sporophytes (offspring) are ideal for studying the evolution of 'parental care' in non-animal organisms. Here, we propose a model of a haploid-diploid life cycle and examine the evolution of maternal investment in sporophytes focusing on two effects: the degree of paternal or maternal control of investment and the number of sporophytes. We find that when the female dominantly controls the investment, the evolutionarily stable level of investment is that which maximizes the expected reproductive success of the female gametophyte. The genomic conflict between maternal and paternal alleles complicates the evolutionary outcome; however, a greater male allelic effect and a higher number of sporophytes favour a higher energy investment, which may lead to evolutionary branching or run-away escalation of the investment level. This suggests that the selfishness of the paternal gene is the evolutionary driver of parental care and that complex structures such as fusion cells in red algae may have evolved to suppress it.


Assuntos
Briófitas , Diploide , Haploidia , Plantas , Reprodução/genética
3.
Glob Chang Biol ; 30(1): e17103, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273556

RESUMO

Living in a warming world requires adaptations to altered annual temperature regimes. In Europe, spring is starting earlier, and the vegetation period is ending later in the year. These climatic changes are leading not only to shifts in distribution ranges of flora and fauna, but also to phenological shifts. Using long-term observation data of butterflies and moths collected during the past decades across northern Austria, we test for phenological shifts over time and changes in the number of generations. On average, Lepidoptera adults emerged earlier in the year and tended to extend their flight periods in autumn. Many species increased the annual number of generations. These changes were more pronounced at lower altitudes than at higher altitudes, leading to an altered phenological zonation. Our findings indicate that climate change does not only affect community composition but also the life history of insects. Increased activity and reproductive periods might alter Lepidoptera-host plant associations and food webs.


Assuntos
Borboletas , Mariposas , Animais , Temperatura , Estágios do Ciclo de Vida , Altitude , Mudança Climática , Estações do Ano
4.
J Eukaryot Microbiol ; 71(3): e13022, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38402533

RESUMO

Planktonic foraminifera were long considered obligate sexual outbreeders but recent observations have shown that nonspinose species can reproduce by multiple fission. The frequency of multiple fission appears low but the survival rate of the offspring is high and specimens approaching fission can be distinguished. We made use of this observation and established a culturing protocol aimed at enhancing the detection and frequency of fission. Using this protocol, we selectively cultured specimens of Neogloboquadrina pachyderma and raised the frequency of reproduction by fission in culture from 3% in randomly selected specimens to almost 60%. By feeding the resulting offspring different strains of live diatoms, we obtained a thriving offspring population and during the subsequent 6 months of culturing, we observed two more successive generations produced by fission. This provides evidence that in nonspinose species of planktonic foraminifera, reproduction by multiple fission is likely clonal and corresponds to the schizont phase known from benthic foraminifera. We subsequently tested if a similar culturing strategy could be applied to Globigerinita glutinata, representing a different clade of planktonic foraminifera, and we were indeed able to obtain offspring via multiple fission in this species. This work opens new avenues for laboratory-based experimental work with planktonic foraminifera.


Assuntos
Foraminíferos , Reprodução , Foraminíferos/fisiologia , Plâncton , Diatomáceas/crescimento & desenvolvimento , Diatomáceas/fisiologia
5.
Philos Trans A Math Phys Eng Sci ; 382(2278): 20230353, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39069756

RESUMO

This article focuses on characterizing a class of quasi-periodic metamaterials created through the repeated arrangement of an elementary cell in a fixed direction. The elementary cell consists of two building blocks made of elastic materials and arranged according to the generalized Fibonacci sequence, giving rise to a quasi-periodic finite microstructure, also called Fibonacci generation. By exploiting the transfer matrix method, the frequency band structure of selected periodic approximants associated with the Fibonacci superlattice, i.e. the layered quasi-periodic metamaterial, is determined. The self-similarity of the frequency band structure is analysed by means of the invariants of the symplectic transfer matrix as well as the transmission coefficients of the finite clusters of Fibonacci generations. A high-frequency continualization scheme is then proposed to identify integral-type or gradient-type non-local continua. The frequency band structures obtained from the continualization scheme are compared with those derived from the Floquet-Bloch theory to validate the proposed scheme. This article is part of the theme issue 'Current developments in elastic and acoustic metamaterials science (Part 1).'

6.
J Phycol ; 60(3): 724-740, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38698553

RESUMO

Chlainomonas (Chlamydomonadales, Chlorophyta) is one of the four genera of snow algae known to produce annual pink or red blooms in alpine snow. No Chlainomonas species have been successfully cultured in the laboratory, but diverse cell types have been observed from many field-collected samples, from multiple species. The diversity of morphologies suggests these algae have complex life cycles with changes in ploidy. Over 7 years (2017-2023), we observed seasonal blooms dominated by a Chlainomonas species from late spring through the summer months on a snow-on-lake habitat in an alpine basin in the North Cascade Mountains of Washington, USA. The Bagley Lake Chlainomonas is distinct from previously reported species based on morphology and sequence data. We observed a similar collection of cell types observed in other Chlainomonas species, with the addition of swarming biflagellate cells that emerged from sporangia. We present a life cycle hypothesis for this species that links cell morphologies observed in the field to seasonally available habitat. The progression of cell types suggests cells are undergoing both meiosis and fertilization in the life cycle. Since the life cycle is the most fundamental biological feature of an organism, with direct consequences for evolutionary processes, it is critical to understand how snow algal life cycles will influence their responses to changes in their habitat driven by climate warming. For microbial taxa that live in extreme environments and are difficult to culture, temporal field studies, such as we report here, may be key to creating testable hypotheses for life cycles.


Assuntos
Clorófitas , Neve , Clorófitas/fisiologia , Clorófitas/crescimento & desenvolvimento , Washington , Estações do Ano , Estágios do Ciclo de Vida , Lagos
7.
Artigo em Inglês | MEDLINE | ID: mdl-38186187

RESUMO

INTRODUCTION: Previous studies have established a history of shoulder dystocia as an important risk factor for shoulder dystocia, but studies on shoulder dystocia by severity are scarce. It is unknown if shoulder dystocia tends to be passed on between generations. We aimed to assess the recurrence risk of shoulder dystocia by severity in the same woman and between generations on both the maternal and paternal side. We also assessed the likelihood of a second delivery and planned cesarean section after shoulder dystocia. MATERIAL AND METHODS: This was a population-based cohort study, using data from the Medical Birth Registry of Norway. To study recurrence in the same mother, we identified 1 091 067 pairs of first and second, second and third, and third and fourth births in the same mother. To study intergenerational recurrence, we identified an individual both as a newborn and as a mother or father in 824 323 mother-offspring pairs and 614 663 father-offspring pairs. We used Bayesian log-binomial multilevel regression to calculate relative risks (RR) with 95% credible intervals. RESULTS: In subsequent deliveries in the same woman the unadjusted RR of recurrence was 7.05 (95% credible interval 6.39-7.79) and 2.99 (2.71-3.31) after adjusting for possible confounders, including current birthweight. The RRs were higher with severe shoulder dystocia as exposure or outcome. With severe shoulder dystocia as both exposure and outcome, unadjusted and adjusted RR was 20.42 (14.25-29.26) and 6.29 (4.41-8.99), respectively. Women with severe and mild shoulder dystocia and those without had subsequent delivery rates of 71.1, 68.9 and 69.0%, respectively. However, the rates of planned cesarean section in subsequent deliveries for those without shoulder dystocia, mild and severe were 1.3, 5.2 and 16.0%, respectively. On the maternal side the unadjusted inter-generational RR of recurrence was 2.82 (2.25-3.54) and 1.41 (1.05-1.90) on the paternal side. Corresponding adjusted RRs were 1.90 (1.51-2.40) and 1.19 (0.88-1.61), respectively. CONCLUSIONS: We found a strong recurrence risk of shoulder dystocia, especially severe, in subsequent deliveries in the same woman. The inter-generational recurrence risk was higher on the maternal than paternal side. Women with a history of shoulder dystocia had more often planned cesarean section.

8.
BMC Public Health ; 24(1): 1707, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926813

RESUMO

BACKGROUND: Indigenous people in Australia experience far poorer health than non-Indigenous Australians. A growing body of research suggests that Indigenous people who are strong in their cultural identity experience better health than those who are not. Yet little is known about how Indigenous people create and maintain strong cultural identities in the contemporary context. This paper explores how Indigenous people in south-eastern Australia create and maintain strong cultural identities to support their health and wellbeing. METHODS: Data were collected from 44 Indigenous people living in the south-eastern Australian state of Victoria via yarning. Yarning is a cultural mode of conversation that privileges Indigenous ways of knowing, doing and being. Yarning participants were selected for their prominence within Victorian Indigenous health services and/or their prominence within the Victorian Indigenous community services sector more broadly. Due to the restrictions of COVID-19, yarns were conducted individually online via Zoom. Data were analysed employing constructivist grounded theory, which was the overarching qualitative research methodology. RESULTS: All yarning participants considered maintaining a strong cultural identity as vital to maintaining their health and wellbeing. They did this via four main ways: knowing one's Mob and knowing one's Country; connecting with one's own Mob and with one's own Country; connecting with Community and Country more broadly; and connecting with the more creative and/or expressive elements of Culture. Importantly, these practices are listed in order of priority. Indigenous people who either do not know their Mob or Country, or for whom the connections with their own Mob and their own Country are weak, may therefore be most vulnerable. This includes Stolen Generations survivors, their descendants, and others impacted by historical and contemporary child removal practices. CONCLUSIONS: The yarns reveal some of the myriad practical ways that Indigenous people maintain a strong cultural identity in contemporary south-eastern Australia. While programs designed to foster connections to Community, Country and/or Culture may benefit all Indigenous participants, those most disconnected from their Ancestral roots may benefit most. Further research is required to determine how best to support Indigenous Victorians whose connections to their own Mob and their own Country are unable to be (re)built.


Assuntos
Cultura , Nível de Saúde , Povos Indígenas , Bem-Estar Psicológico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Serviços de Saúde do Indígena/organização & administração , Povos Indígenas/psicologia , Pesquisa Qualitativa , Identificação Social , Vitória , Comportamentos Relacionados com a Saúde
9.
Sociol Health Illn ; 46(1): 153-171, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37550844

RESUMO

Despite an increased drive over the past two decades in Western societies to promote children's physically active play to improve their health, there are concerns that childhood has become less physically active. There are also fears that a previously naturally occurring aspect of childhood has become less authentically playful. Both trends highlight changes over time in the amount and type of play practiced by children and are often cited as consequences of generational shifts. Yet, research which analytically employs the concept of generation to connect changes to childhood with relevant social transformations is lacking. Inspired by Mannheim's conceptualisation of generations, this paper draws on life history interviews with 28 United Kingdom residents born between 1950 and 1994 to propose a fracturing of naturally occurring physical activity from childhood play. As shifts in childhood and parenting have become inextricably linked, this argument illustrates the impact of an intensification to parenting upon greater parental surveillance of increasingly organised forms of childhood physical activity at the expense of spontaneous play. Future physical activity policy should be sensitive to the social climate in which recommendations for children are made, as this places expectations upon parents due to how childhood is currently understood within neoliberal contexts.


Assuntos
Poder Familiar , Pais , Criança , Humanos , Meio Social , Reino Unido , Exercício Físico
10.
Nano Lett ; 23(19): 9003-9010, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37756214

RESUMO

Nonlinear optical metasurfaces offer a possibility to perform frequency mixing without the phase-matching constraints of bulk nonlinear crystals and with control of the local nonlinear response at a sub-wavelength scale. Nonlinear inter-subband polaritonic metasurfaces created by combining the semiconductor heterostructures with quantum-engineered inter-subband nonlinear response and electromagnetically engineered metal-clad nanoresonators offer by far the largest second-order nonlinear response of all condensed matter systems reported to date. However, the nonlinear optical response of these metasurfaces is limited by optical intensity saturation in the nanoresonator hot spots that prevented the achievement of power conversion efficiencies over 0.2% in three-wave mixing experiments. In this study, we propose and experimentally demonstrate dielectric inter-subband polaritonic metasurfaces for second-harmonic generation that achieve 0.37% power conversion efficiency. Our structure is created by a new design approach that combines dielectric resonators inducing Mie resonant modes with a lattice resonance to achieve a uniform and high field enhancement throughout the meta-atom volume.

11.
BMC Nurs ; 23(1): 252, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643129

RESUMO

BACKGROUND: Job satisfaction has garnered significant interest across multiple disciplines as it plays a vital role in shaping human resource strategies. In the field of nursing, enhancing job satisfaction can help prevent workforce shortages. Work values and job-related characteristics are significant predictors of job satisfaction. However, the influence of factors may change as younger generations join the nursing workforce. Although research on generational commonalities and differences in work values is increasing, there is insufficient information on generational differences in the interplay between work values and job satisfaction. This study investigated the factors associated with job satisfaction of new nurses in each generational group based on a work value perspective. METHODS: A total of 280 new nurses (151 from Generation Y and 129 from Generation Z) were selected from the Graduates Occupational Mobility Survey. Multiple linear regression analyses were performed to determine the factors associated with job satisfaction in both groups. RESULTS: Most participants graduated with a diploma (61.1%), were paid less than the average salary of each group (60.4%), and conducted shift (72.9%) and overtime work (64.3%). Work values and job satisfaction levels were not significantly different between the two groups. Multiple linear regression analyses showed that career growth and task work values were associated with job satisfaction for Generation Z, while task, reputation, and environment work values were associated with job satisfaction for Generation Y. Among the job-related characteristics, nurses' job tenure was associated with job satisfaction in both groups; salary and overtime had varying relationships with job satisfaction between the two generations. CONCLUSIONS: Understanding generational differences is crucial for improving the effective management of new generational nurses. Our study findings support that different work value dimensions and job-related characteristics were associated with job satisfaction in each generation. Accordingly, it is essential to develop distinct initiatives, such as a well-structured program, to support the continued career growth of the new Generation Z nurses, thereby enhancing their job satisfaction. Furthermore, providing a conducive working environment that helps new-generation nurses overcome challenges and ensures personal lives should be considered.

12.
Sci Eng Ethics ; 30(4): 37, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39120832

RESUMO

I defend the claim that life-suspending technologies can constitute a catastrophic and existential security factor for risks structurally similar to those related to climate change. The gist of the argument is that, under certain conditions, life-suspending technologies such as cryonics can provide self-interested actors with incentives to efficiently tackle such risks-in particular, they provide reasons to overcome certain manifestations of generational egoism, a risk factor of several catastrophic and existential risks. Provided we have reasons to decrease catastrophic and existential risks such as climate change, we also have a (defeasible) reason for investing in developing and making life-suspending technologies (more) widespread.


Assuntos
Mudança Climática , Humanos , Tecnologia , Risco , Existencialismo , Princípios Morais , Medidas de Segurança
13.
Br Poult Sci ; 65(1): 19-27, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38018666

RESUMO

1. Mycoplasma synoviae (MS) is the primary causative agent of synovitis in avian species. In order to investigate the pathogenicity and immunological responses associated with MS in specific pathogen-free chicken embryos, a series of generations (F1, F95, F120, F160 and F200) of MS were introduced into 7-day-old SPF chicken embryos and subsequent mortality rates were recorded and analysed2. Reverse transcription-quantitative polymerase chain reaction was performed to detect expression of heat shock proteins HSP27, HSP40, HSP60, HSP70 and HSP90 and inflammatory factors interleukin (IL)-1ß, caspase-1 and IL-18 in the tracheal tissue.3. The results showed that the mortality rate of SPF chicken embryos decreased with an increase in the number of passages, with the highest being 80% (8/10) for F1 generation and the lowest being 10% (1/10) for F200. The expression of HSP27, IL-1ß, HSP40, caspase-1, HSP70 and HSP90 showed a significant downregulation trend with an increase in the generation (except IL-18; P < 0.05). The HSP60 expression was significantly upregulated with increasing generations (P < 0.05).4. A relationship between pathogenicity and the number of passages was observed and the decrease in pathogenicity appeared to be associated with HSP and genes related to inflammatory factors. The present work offers a scientific foundation for screening potential MS strains that might be employed to develop attenuated vaccines.


Assuntos
Galinhas , Mycoplasma synoviae , Embrião de Galinha , Animais , Virulência , Proteínas de Choque Térmico HSP27/genética , Interleucina-18/genética , Mycoplasma synoviae/genética , Proteínas de Choque Térmico HSP70 , Proteínas de Choque Térmico HSP90/genética , Interleucina-1beta/genética , Caspases
14.
World J Microbiol Biotechnol ; 40(6): 193, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709343

RESUMO

The rapid industrial revolution significantly increased heavy metal pollution, becoming a major global environmental concern. This pollution is considered as one of the most harmful and toxic threats to all environmental components (air, soil, water, animals, and plants until reaching to human). Therefore, scientists try to find a promising and eco-friendly technique to solve this problem i.e., bacterial bioremediation. Various heavy metal resistance mechanisms were reported. Omics technologies can significantly improve our understanding of heavy metal resistant bacteria and their communities. They are a potent tool for investigating the adaptation processes of microbes in severe conditions. These omics methods provide unique benefits for investigating metabolic alterations, microbial diversity, and mechanisms of resistance of individual strains or communities to harsh conditions. Starting with genome sequencing which provides us with complete and comprehensive insight into the resistance mechanism of heavy metal resistant bacteria. Moreover, genome sequencing facilitates the opportunities to identify specific metal resistance genes, operons, and regulatory elements in the genomes of individual bacteria, understand the genetic mechanisms and variations responsible for heavy metal resistance within and between bacterial species in addition to the transcriptome, proteome that obtain the real expressed genes. Moreover, at the community level, metagenome, meta transcriptome and meta proteome participate in understanding the microbial interactive network potentially novel metabolic pathways, enzymes and gene species can all be found using these methods. This review presents the state of the art and anticipated developments in the use of omics technologies in the investigation of microbes used for heavy metal bioremediation.


Assuntos
Bactérias , Biodegradação Ambiental , Metais Pesados , Metais Pesados/metabolismo , Bactérias/genética , Bactérias/metabolismo , Bactérias/efeitos dos fármacos , Genoma Bacteriano , Proteômica , Transcriptoma , Metagenômica , Metagenoma , Genômica , Farmacorresistência Bacteriana/genética
15.
Br J Sociol ; 75(1): 93-107, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37947454

RESUMO

This article critically employs the case of association football in England, from 1980 to 2023, as a social movement timescape, to examine the political consciousness and long-term mobilisations of a generation of football supporter activists, and their capacity to influence politics, and respond to new, emerging, critical junctures, through networks of trust and shared memories of historical events. This is of crucial importance to sociology because it reveals the tensions between what are considered legitimate and illegitimate social practices which characterise contemporary society's moral economy. Focusing on temporal contestations over regulation, policing, governance and cultural rituals, the article deconstructs the role of generations in social movements, and critically synthesises relational-temporal sociology and classic and contemporary work on the sociology of generations, to show how legacy operates as a multifaceted maturing concept of power and time. In English football's neoliberal timescape, the supporters' movement has reached a critical juncture; the future will require a new generation of activists, to negotiate, resist and contest the new hegemonic politics of social control and supporter engagement.


Assuntos
Futebol , Mudança Social , Humanos , Sociologia , Inglaterra , Política
16.
Small ; 19(43): e2303156, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37376814

RESUMO

The development of cost-effective and reliable metal-free carbon-based electrocatalysts has gained significant attention for electrochemical hydrogen peroxide (H2 O2 ) generation through a two-electron oxygen reduction reaction. In this study, a scalable solvent engineering strategy is employed to fabricate oxygen-doped carbon dots (O-CDs) that exhibit excellent performance as electrocatalysts. By adjusting the ratio of ethanol and acetone solvents during the synthesis, the surface electronic structure of the resulting O-CDs can be systematically tuned. The amount of edge active CO group was strongly correlated with the selectivity and activity of the O-CDs. The optimum O-CDs-3 exhibited extraordinary H2 O2 selectivity of up to 96.55% (n = 2.06) at 0.65 V (vs RHE) and achieved a remarkably low Tafel plot of 64.8 mV dec-1 . Furthermore, the realistic H2 O2 productivity yield of flow cell is measured to be as high as 111.18 mg h-1  cm-2 for a duration of 10 h. The findings highlight the potential of universal solvent engineering approach for enabling the development of carbon-based electrocatalytic materials with improved performance. Further studies will be undertaken to explore the practical implications of the findings for advancing the field of carbon-based electrocatalysis.

17.
Virus Genes ; 59(5): 662-669, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37308753

RESUMO

Failure to neutralize HBsAg and subsequent escape from the host immune system may be caused by HBsAg mutations, particularly in the "a" determinant, which alters the antigenicity of the protein. The purpose of this study was to examine the frequency of S gene mutations in three generations of HBV cases in northeastern Iran. In this study, 90 patients with chronic HBV were assigned to three groups according to the inclusion criteria. The plasma were utilized to extract viral DNA, and the PCR was applied. Direct sequencing and alignment were performed on the S gene, using reference sequence. The results indicated that all HBV genomes were categorized as the genotype D/ayw2. Among 79 point mutations detected, 36.8% were silent, and 56.2% were missense. In the S region, mutations were observed in 88.9% of CHB subjects studied. In the three-generation group, 21.5% of mutations were in the "a" determinant, and 2.6%, 19.5%, and 87.0% of these mutations were observed in antigenic epitopes of CTLs, CD4+, and B cells, respectively. In addition, 56.7% of mutations occurred at Major Hydrophilic Region. S143L and G145R mutations which the most prevalent in the three-generation (36.7%, 20%), and two-generation (42.5%, 20%) groups, related to the failure of HBsAg detection, vaccine, and immunotherapy escape. The findings showed that most of the mutations were concentrated in the B cell epitope. Most CHB cases from the three-generation, especially grandmothers, had HBV S gene mutations and subsequent amino acid mutations, suggesting that these mutations may be critical for pathogenesis and vaccine evasion.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Vírus da Hepatite B/genética , Antígenos de Superfície da Hepatite B/genética , Mutação , Vacinas contra Hepatite B , Genótipo , DNA Viral/genética , DNA Viral/química
18.
Demography ; 60(1): 99-122, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36541562

RESUMO

Formal volunteering holds great importance for the recipients of volunteer services, individuals who volunteer, and the wider society. However, how much recent birth cohorts volunteer in middle and late adulthood compared with earlier birth cohorts is not well understood. Even less well-known are the age and cohort trends in informal helping provided to friends and neighbors in later adulthood. Using longitudinal data from the Health and Retirement Study, we estimated age and cohort trends in formal volunteering and informal helping from 1998 to 2018 for a wide range of birth cohorts born between 1909 and 1958. We used multivariate, multilevel models based on Bayesian generalized modeling methods to estimate the probabilities of volunteering and informal helping simultaneously in a single model. Despite having advantages in human and health capital, recent birth cohorts showed volunteering levels in late adulthood that are similar to those of their predecessors. Moreover, more recent birth cohorts were consistently less engaged in informal helping than earlier birth cohorts throughout the observation period. More research is needed to illuminate the sociocultural drivers of changes in helping behaviors and overall prosocial and civic engagement.


Assuntos
Aposentadoria , Humanos , Adulto , Teorema de Bayes , Voluntários
19.
J Med Ethics ; 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37527926

RESUMO

Targeted modifications of the human epigenome, epigenome editing (EE), are around the corner. For EE, techniques similar to genome editing (GE) techniques are used. While in GE the genetic information is changed by directly modifying DNA, intervening in the epigenome requires modifying the configuration of DNA, for example, how it is folded. This does not come with alterations in the base sequence ('genetic code'). To date, there is almost no ethical debate about EE, whereas the discussions about GE are voluminous. Our article introduces EE into bioethics by translating knowledge from science to ethics and by comparing the risks of EE with those of GE. We, first (I), make the case that a broader ethical debate on EE is due, provide scientific background on EE, compile potential use-cases and recap previous debates. We then (II) compare EE and GE and suggest that the severity of risks of novel gene technologies depends on three factors: (i) the choice of an ex vivo versus an in vivo editing approach, (ii) the time of intervention and intervention windows and (iii) the targeted diseases. Moreover, we show why germline EE is not effective and reject the position of strong epigenetic determinism. We conclude that EE is not always ethically preferable to GE in terms of risks, and end with suggestions for next steps in the current ethical debate on EE by briefly introducing ethical challenges of new areas of preventive applications of EE (III).

20.
BMC Public Health ; 23(1): 484, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36915081

RESUMO

BACKGROUND: The study of climate change through a generational lens is meaningful when one considers the distinct attitudes, behaviors, values, and motivations of each generation. Individuals born between 1980 and 1999, referred to as the Millennial Generation (Millennials) and individuals born up to five years before or after 2000, referred to as Generation Z (Gen Z), may differ widely in their views, values, attitudes, and behaviors. This may lead to conflicts between these two cohorts. As Gen Z enters the labor market, their first-level supervisors will be, in many cases, the Millennials, who may view the topic of climate change-health concern nexus very differently than their Gen Z subordinates. Considering the perspectives of each generation may offer insights on how to engage them to act in an environmentally responsible way to counteract climate change effects. OBJECTIVE: The study reveals similarities and differences in how Millennials and Gen Z perceive the climate change-health concern nexus, which illuminates the understanding of the potential generational conflicts and the critical points where intervention is needed. METHOD: Interview data from 41 participants were analyzed via thematic analysis using the Quirkos software program. Reporting is in accordance with the COREQ guidelines. RESULTS: The interview questions elicited responses related to five dimensions: (i) Views of individual and community health; (ii) Knowledge around climate change; (iii) Perceived health impact; (iv) Attitudes towards climate change; (v) Behaviors related to climate change. The findings revealed a set of commonalities and differences in understanding the climate change-health concern nexus between the participants representative of each of the generations examined. One main result is that while most interviewees perceived changes in summer and winter temperatures, they failed to articulate how climate change affected their health. CONCLUSION: Thematic analysis revealed that the commonalities of views outweigh the differences between the two generations. A relevant remark is that participants can be described rather as "observers" than "players" since they do not tend to see themselves (through their behavior and their contribution) as active participants in the goal to fight climate change. Consequently, both generations undergo what Stephen Gardiner [1] called "intergenerational buck-passing."


Assuntos
Mudança Climática , Leitura , Humanos , Motivação , Atitude , Relação entre Gerações
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