Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
1.
Sci Rep ; 14(1): 3263, 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38332037

RESUMEN

The success of an on-line movement could be defined in terms of the shift to large-scale and the later off-line massive street actions of protests. The role of social media in this process is to facilitate the transformation from small or local feelings of disagreement into large-scale social actions. The way how social media achieves that effect is by growing clusters of people and groups with similar effervescent feelings, which otherwise would not be in touch with each other. It is natural to think that these kinds of macro social actions, as a consequence of the spontaneous and massive interactions, will attain the growth and divergence of those clusters, like the correlation length of statistical physics, giving rise to important simplifications on several statistics. In this work, we report the presence of signs of criticality in social demonstrations. Namely, similar power-law exponents are found whenever the distributions are calculated either considering time windows of the same length or with the same number of hashtag usages. In particular, the exponents for the distributions during the event were found to be smaller than before the event, and this is also observed either if we count the hashtags only once per user or if all their usages are considered. By means of network representations, we show that the systems present two kinds of high connectedness, characterised by either high or low values of modularity. The importance of analysing systems near a critical point is that any small disturbance can escalate and induce large-scale-nationwide-chain reactions.

2.
Front Pharmacol ; 14: 1275095, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38074151

RESUMEN

Background: Recent studies have demonstrated that patients with type 2 diabetes mellitus (T2DM) who receive metformin have a decreased risk of developing age-related macular degeneration (AMD). However, other studies have also suggested that metformin may increase the risk of AMD development. Therefore, this study investigated the association between treatment with metformin and the risk of AMD in patients with T2DM by using Taiwan' National Health Insurance Research Database. Methods: Patients who received a diagnosis of new-onset T2DM between 2002 and 2013 were enrolled in this study. The patients were divided into patients treated and not treated with metformin to evaluate the risk of AMD after 5 years of follow-up. The logistic regression was used to estimate the risk of AMD associated with the intensity of treatment with metformin. Result: A total of 7 517 patients (103.16 patients per 10,000 people) developed AMD in 5 years after DM diagnosis. After adjusting for the relevant variables, patients with T2DM treated with <5 defined daily dose (DDD)/month of metformin had a lower risk of AMD (odds ratios [OR]: 0.93; 95% confidence interval [CI]: 0.88 0.99). Patients treated with >25 DDD/month of metformin had a higher risk of AMD (OR: 1.39; 95% CI: 1.08-1.78). Conclusion: Metformin use may be associated with a risk of AMD among patients with T2DM in a dose-dependent association manner, with the greater benefit at lower DDD/month. However, higher DDD/month exhibited an increased risk of AMD.

3.
JBI Evid Implement ; 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37982206

RESUMEN

INTRODUCTION AND OBJECTIVES: A central venous catheter (CVC)-a type of central venous access device (CVAD)-is the most common intervention for critical illnesses. Obstruction of the CVC can lead to fatal consequences. Thus, it is critical to maintain catheter lumen patency. The CVC occlusion rate in a hospital in Taiwan was 33%. This project aimed to decrease the CVC occlusion rate in acute care. METHODS: This project was conceptually informed by the JBI Evidence-Based Model of Healthcare, in particular, the conceptualization of evidence implementation as inclusive of context analysis, implementation, and evaluation of outcomes using evidence-based quality indicators. As part of the seven-phase implementation process, we used audit and feedback in a pre- and post-test design to measure baseline compliance. Based on the initial audit, we developed an implementation strategy responsive to the identified gaps in compliance. We then undertook a final audit to measure changes in compliance to evaluate our implementation effects. The JBI software, PACES, and the situational analysis software, GRiP, were used for data collection and implementation planning. There were six evidence-based criteria, with a sample size of 30 nurses for each criterion. The team carried out the project from September 2022 to January 2023. RESULTS: Post-implementation audit compliance rates increased to 100% for the following criteria: the organization had a standardized flushing and locking solution protocol (0%), the CVAD lumen was locked upon completion of the final flush (10%), a single-dose system was used for flushing and locking the CVAD (60%), and preservative-free 0.9% sodium chloride was used to flush the CVAD (60%). Furthermore, the CVC occlusion rate decreased from 33% to 5%. CONCLUSIONS: The project successfully decreased the rate of CVC occlusion and increased the competence of nurses in acute care settings. The implementation of best practices in clinical care should focus on leadership, cross-department coordination, education, and innovation.

4.
J Pers Med ; 13(5)2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37240908

RESUMEN

The evidence of metformin's effect on dementia is conflicting. This study investigates the association between metformin use and the risk of dementia among patients with diabetes mellitus (DM). This study included patients with new-onset DM between 2002 and 2013. We divided the patients into patients who used metformin and patients who did not. Two models were used to assess metformin use: the cumulative defined daily dose (cDDD) of metformin use and the intensity of metformin use. This study with 3-year and 5-year follow-ups investigated the risk of dementia among patients with DM who used metformin. At the 3-year follow-up, patients who received cDDD < 300 had an odds ratio (OR) of developing dementia of 0.92 (95% confidence interval [CI] = 0.89-0.96); patients who used metformin at intensities <10 and 10-25 DDD/month had ORs of 0.92 (95% CI: 0.87-0.97) and 0.92 (95% CI: 0.85-1.00), respectively. Metformin use at cDDD 300-500 (OR = 0.80, 95% CI = 0.56-1.15) or >500 (OR = 1.48, 95% CI = 0.48-4.60) or at an intensity >25 DDD/month (OR = 0.84, 95% CI = 0.60-1.18) were not associated with an incident of dementia. There were similar results at the 5-year follow-up. Patients with a low intensity of metformin use had a lower risk of dementia. However, higher doses of metformin with higher intensity exhibited no protective role in dementia. Prospective clinical trials are warranted to evaluate the actual underlying mechanisms between metformin dosage and the risk of dementia.

5.
Front Endocrinol (Lausanne) ; 13: 1027484, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36531446

RESUMEN

Background and aims: Studies have demonstrated that the short-term use of metformin benefits liver function among patients with type 2 diabetes mellitus (T2DM). However, few studies have reported on the effects of long-term metformin treatment on liver function or liver histology. This study investigated the correlation between metformin use and the incidence of nonalcoholic fatty liver disease (NAFLD) among patients with T2DM. Methods: This population-based study investigated the risk of NAFLD among patients with T2DM who received metformin treatment between 2001-2018. Metformin users and metformin nonusers were enrolled and matched to compare the risk of NAFLD. Results: After 3 years, the patients who received <300 cDDD of metformin and those with metformin use intensity of <10 and 10-25 DDD/month had odds ratios (ORs) of 1.11 (95% confidence interval [CI] = 1.06-1.16), 1.08 (95% CI = 1.02-1.13), and 1.18 (95% CI = 1.11-1.26) for NAFLD, respectively. Moreover, metformin users who scored high on the Diabetes Complications and Severity Index (DCSI) were at high risk of NAFLD. Patients with comorbid hyperlipidemia, hyperuricemia, obesity, and hepatitis C were also at high risk of NAFLD. Conclusion: Patients with T2DM who received metformin of <300 cDDD or used metformin at an intensity of <10 and 10-25 DDD/month were at a high risk of developing NAFLD. The results of this study also indicated that patients with T2DM receiving metformin and with high scores on the DCSI were at a high risk of developing NAFLD.


Asunto(s)
Diabetes Mellitus Tipo 2 , Metformina , Enfermedad del Hígado Graso no Alcohólico , Humanos , Metformina/uso terapéutico , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/epidemiología , Incidencia , Estudios de Cohortes
6.
J Fungi (Basel) ; 9(1)2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36675844

RESUMEN

Few studies have comprehensively investigated the occurrence of Pneumocystis jirovecii pneumonia (PJP) among solid organ transplant (SOT) recipients. This study investigated the risk of PJP after organ transplantation. Each patient who underwent SOT was propensity-score-matched with four non-SOT individuals in terms of sex, age, insured salary, urbanization of residence, comorbidities, and year of enrollment. When considering the 3-year follow-up, the patients who had undergone SOT were at higher risk of PJP, with the adjusted odds ratio (aOR) being 17.18 (95% confidence interval (CI): 8.80-33.53). Furthermore, SOT recipients were also at higher PJP risk than the patients without SOT at 6 months, 1 year, and 2 years, with the aOR being 22.64 (95% CI: 7.53-68.11), 26.19 (95% CI: 9.89-69.37), and 23.06 (95% CI: 10.23-51.97), respectively. Patients comorbid with HIV infection, hematological malignancies, or vasculitis were at higher risk (aOR = 59.08, 95% CI = 20.30-171.92), (aOR = 11.94, 95% CI = 5.36-26.61), and (aOR = 21.72, 95% CI = 2.41-195.81), respectively. The recipients of SOT were at higher risk of PJP, and PJP can develop at any stage after transplantation. SOT recipients comorbid with HIV, hematologic malignancies, or vasculitis were at higher PJP risk.

7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 6353-6356, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34892566

RESUMEN

Neural development of infants has drawn increasing research interests from the community. In this paper, we investigated the frequency band power of 112 infants who participated in an auditory oddball experiment, and the visual expectation (VE) score of 177 infants who went through a visual expectation paradigm test. Analysis found that the frequency band power decreases in the delta and theta bands, and increases in the alpha and beta bands when the infants grow up from 6 months old to 18 months old. We also proposed a sustainability index to measure the capability of a subject to maintain their band power in the auditory oddball experiment when infants grow up from 6 months old to 18 months old. Analysis shows that the sustainability index increased significantly in the alpha and beta band, decreased in the delta and theta bands. Correlation between the VE score and frequency band power was investigated on 47 infants who participated in both auditory oddball experiment and visual expectation paradigm test. Analysis shows that the reaction speed to stimulus have statistical a significant correlation with the changes of band power and sustainability index in posterior and temporal section, and in the higher frequency bands.


Asunto(s)
Electroencefalografía , Humanos , Lactante
8.
Phys Rev Lett ; 127(16): 168301, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34723574

RESUMEN

We propose a Hamiltonian approach to reproduce the relevant elements of the centuries-old Subak irrigation system in Bali, showing a cluster-size distribution of rice-field patches that is a power-law with an exponent of ∼2. Besides this exponent, the resulting system presents two equilibria. The first originates from a balance between energy and entropy contributions. The second arises from the specific energy contribution through a local Potts-type interaction in combination with a long-range antiferromagnetic interaction without attenuation. Finite-size scaling analysis shows that, as a result of the second equilibrium, the critical transition balancing energy and entropy contributions at the Potts (local ferromagnetic) regime is absorbed by the transition driven by the global-antiferromagnetic interactions, as the system size increases. The phase transition balancing energy and entropy contributions at the global-antiferromagnetic regime also shows signs of criticality. Our study extends the Hamiltonian framework to a new domain of coupled human-environmental interactions.

9.
Eur J Epidemiol ; 36(1): 129-142, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33222050

RESUMEN

The Singapore Preconception Study of Long-Term Maternal and Child Outcomes (S-PRESTO) is a preconception, longitudinal cohort study that aims to study the effects of nutrition, lifestyle, and maternal mood prior to and during pregnancy on the epigenome of the offspring and clinically important outcomes including duration of gestation, fetal growth, metabolic and neural phenotypes in the offspring. Between February 2015 and October 2017, the S-PRESTO study recruited 1039 Chinese, Malay or Indian (or any combinations thereof) women aged 18-45 years and who intended to get pregnant and deliver in Singapore, resulting in 1032 unique participants and 373 children born in the cohort. The participants were followed up for 3 visits during the preconception phase and censored at 12 months of follow up if pregnancy was not achieved (N = 557 censored). Women who successfully conceived (N = 475) were characterised at gestational weeks 6-8, 11-13, 18-21, 24-26, 27-28 and 34-36. Follow up of their index offspring (N = 373 singletons) is on-going at birth, 1, 3 and 6 weeks, 3, 6, 12, 18, 24 and 36 months and beyond. Women are also being followed up post-delivery. Data is collected via interviewer-administered questionnaires, metabolic imaging (magnetic resonance imaging), standardized anthropometric measurements and collection of diverse specimens, i.e. blood, urine, buccal smear, stool, skin tapes, epithelial swabs at numerous timepoints. S-PRESTO has extensive repeated data collected which include genetic and epigenetic sampling from preconception which is unique in mother-offspring epidemiological cohorts. This enables prospective assessment of a wide array of potential determinants of future health outcomes in women from preconception to post-delivery and in their offspring across the earliest development from embryonic stages into early childhood. In addition, the S-PRESTO study draws from the three major Asian ethnic groups that represent 50% of the global population, increasing the relevance of its findings to global efforts to address non-communicable diseases.


Asunto(s)
Estilo de Vida , Conducta Materna , Estado Nutricional , Vigilancia de la Población/métodos , Atención Preconceptiva/estadística & datos numéricos , Atención Prenatal/estadística & datos numéricos , Adolescente , Adulto , Afecto , Femenino , Humanos , Estudios Longitudinales , Fenómenos Fisiologicos Nutricionales Maternos , Persona de Mediana Edad , Embarazo , Resultado del Embarazo/epidemiología , Medición de Riesgo , Singapur/epidemiología , Adulto Joven
10.
Gut Pathog ; 12: 6, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32025243

RESUMEN

BACKGROUND: As more animal studies start to disentangle pathways linking the gut microbial ecosystem and neurobehavioral traits, human studies have grown rapidly. Many have since investigated the bidirectional communication between the gastrointestinal tract and the central nervous system, specifically on the effects of microbial composition on the brain and development. METHODS: Our review at the initial stage aimed to evaluate literature on gut microbial alterations in pediatric neurobehavioral conditions. We searched five literature databases (Embase, PubMed, PsychInfo, Scopus, and Medline) and found 4489 published work. As the mechanisms linking gut microbiota to these conditions are divergent, the scope of this review was narrowed to focus on describing gut dysbiosis in children with autism spectrum disorder (ASD). RESULTS: Among the final 26 articles, there was a lack of consistency in the reported gut microbiome changes across ASD studies, except for distinguishable patterns, within limits, for Prevotella, Firmicutes at the phylum level, Clostridiales clusters including Clostridium perfringens, and Bifidobacterium species. CONCLUSIONS: These results were inadequate to confirm a global microbiome change in children with ASD and causality could not be inferred to explain the etiology of the behaviors associated with ASD. Mechanistic studies are needed to elucidate the specific role of the gut microbiome in the pathogenesis of ASD.

11.
R Soc Open Sci ; 6(8): 190733, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31598251

RESUMEN

Population genetics has been successful at identifying the relationships between human groups and their interconnected histories. However, the link between genetic demography inferred at large scales and the individual human behaviours that ultimately generate that demography is not always clear. While anthropological and historical context are routinely presented as adjuncts in population genetic studies to help describe the past, determining how underlying patterns of human sociocultural behaviour impact genetics still remains challenging. Here, we analyse patterns of genetic variation in village-scale samples from two islands in eastern Indonesia, patrilocal Sumba and a matrilocal region of Timor. Adopting a 'process modelling' approach, we iteratively explore combinations of structurally different models as a thinking tool. We find interconnected socio-genetic interactions involving sex-biased migration, lineage-focused founder effects, and on Sumba, heritable social dominance. Strikingly, founder ideology, a cultural model derived from anthropological and archaeological studies at larger regional scales, has both its origins and impact at the scale of villages. Process modelling lets us explore these complex interactions, first by circumventing the complexity of formal inference when studying large datasets with many interacting parts, and then by explicitly testing complex anthropological hypotheses about sociocultural behaviour from a more familiar population genetic standpoint.

12.
Sci Rep ; 9(1): 6887, 2019 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-31053731

RESUMEN

Bus bunching is a perennial phenomenon that not only diminishes the efficiency of a bus system, but also prevents transit authorities from keeping buses on schedule. We present a physical theory of buses serving a loop of bus stops as a ring of coupled self-oscillators, analogous to the Kuramoto model. Sustained bunching is a repercussion of the process of phase synchronisation whereby the phases of the oscillators are locked to each other. This emerges when demand exceeds a critical threshold. Buses also bunch at low demand, albeit temporarily, due to frequency detuning arising from different human drivers' distinct natural speeds. We calculate the critical transition when complete phase locking (full synchronisation) occurs for the bus system, and posit the critical transition to completely no phase locking (zero synchronisation). The intermediate regime is the phase where clusters of partially phase locked buses exist. Intriguingly, these theoretical results are in close correspondence to real buses in a university's shuttle bus system.

13.
JMIR Res Protoc ; 8(2): e11629, 2019 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-30707101

RESUMEN

BACKGROUND: This study aims to examine the adaptive process of children and mothers from multistressed low-income families in Singapore. It aims to bridge the knowledge gap left by existing poverty studies, which are predominately risk focused. Through a sequential longitudinal mixed-methods design, we will differentiate children and mothers who demonstrate varied social, developmental, and mental health trajectories of outcomes. Through utilizing the Latent Growth Curve Model (LGCM), we aim to detect the development and changes of the positive Family Agency and adaptive capacities of these families over time. The construct of Family Agency is underpinned by the theoretical guidance from the Social Relational Theory, which examines child agency, parent agency, relational agency, and the interactions among these members. It is hypothesized that positive Family Agency within low-income families may lead to better outcomes. The key research questions include whether the extent of positive Family Agency mediates the relationship among financial stress, resource utilization, home environment, and parental stress. OBJECTIVE: The study elucidates the Family Agency construct through interviews with mother-child dyads. It also aims to understand how financial stress and resources are differentially related to home environment, parent stress, and parent and child outcomes. METHODS: In phase 1, 60 mother-child dyads from families receiving government financial assistance and with children aged between 7 and 12 years will be recruited. In-depth interviews will be conducted separately with mothers and children. On the basis of 120 interviews, a measurement for the construct of Family Agency will be developed and will be pilot tested. In phase 2a, a longitudinal survey will be conducted over 3 time points from 800 mother-child dyads. The 3 waves of survey results will be analyzed by LGCM to identify the trajectories of adaptation pathways of these low-income families. In addition, 10 focus groups with up to 15 participants in each will be conducted to validate the LGCM results. RESULTS: This project is funded by the Social Science Research Thematic Grant (Singapore). The recruitment of 60 mother-child dyads has been achieved. Data collection will commence once the amendment to the protocol has been approved by the Institutional Review Board. Analysis of phase 1 data will be completed by the end of the first quarter of 2019, and the first set of results is expected to be submitted for publication by the second quarter of 2019. Phase 2 implementation will commence in the second quarter of 2019, and the project end date is in May 2021. CONCLUSIONS: Findings from this study can potentially inform social policy and programs as it refines the understanding of low-income families by distinguishing trajectories of adaptive capacities so that policies and interventions can be targeted in enhancing the adaptive pathways of low-income families with children. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/11629.

14.
Proc Natl Acad Sci U S A ; 114(49): 12910-12915, 2017 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-29158378

RESUMEN

Languages are transmitted through channels created by kinship systems. Given sufficient time, these kinship channels can change the genetic and linguistic structure of populations. In traditional societies of eastern Indonesia, finely resolved cophylogenies of languages and genes reveal persistent movements between stable speech communities facilitated by kinship rules. When multiple languages are present in a region and postmarital residence rules encourage sustained directional movement between speech communities, then languages should be channeled along uniparental lines. We find strong evidence for this pattern in 982 individuals from 25 villages on two adjacent islands, where different kinship rules have been followed. Core groups of close relatives have stayed together for generations, while remaining in contact with, and marrying into, surrounding groups. Over time, these kinship systems shaped their gene and language phylogenies: Consistently following a postmarital residence rule turned social communities into speech communities.


Asunto(s)
Lenguaje , ADN Mitocondrial/genética , Familia , Femenino , Variación Genética , Migración Humana , Humanos , Indonesia , Islas , Lingüística , Masculino , Filogenia , Análisis de Secuencia de ADN
15.
J Microbiol Immunol Infect ; 50(6): 915-922, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28882583

RESUMEN

BACKGROUND: Acute gastroenteritis (AGE) can be caused by a wide array of pathogens, including bacteria, viruses, and parasites. A prospective study to investigate the epidemiology and clinical presentation in young children hospitalized with AGE was conducted in a medical center in southern Taiwan. METHODS: Patients aged less than 5 years who was hospitalized due to AGE in National Cheng Kung University Hospital were enrolled from July 2014 to June 2016. The demographic information, clinical features and laboratory data were collected by chart reviews, and stool samples were sent to Centers of Disease Control, Taiwan (Taiwan CDC) for a panel of pathogen identification consisting of two viruses, nine bacteria, and five parasites. RESULTS: Totally 441 patients were enrolled in this study. Salmonella spp. was the leading cause of disease (21.8%), followed by norovirus (17.0%), Clostridium difficile (9.5%), and rotavirus (9.3%). Norovirus identification rate was the highest among patients less than 6 months of age, while Salmonella was highest among patients between 2 and 3 years old. Patients with Salmonella infection frequently presented with fever, lethargy, bloody stool, and elevated serum level of C-reactive protein (CRP); norovirus and rotavirus infection frequently presented with vomiting. Salmonella gastroenteritis also resulted in longer hospitalization and more frequent antibiotics administration. C. difficile could be isolated from both gastroenteritis patients and control children. CONCLUSION: Salmonella spp. was the most common pathogen of AGE in hospitalized children in southern Taiwan during 2014-2016, followed by norovirus and rotavirus. Further monitoring of epidemiology characteristics among cardinal pathogens of pediatric gastroenteritis is necessary.


Asunto(s)
Infecciones por Caliciviridae/epidemiología , Gastroenteritis/epidemiología , Gastroenteritis/microbiología , Infecciones por Rotavirus/epidemiología , Infecciones por Salmonella/epidemiología , Infecciones por Caliciviridae/diagnóstico , Infecciones por Caliciviridae/tratamiento farmacológico , Preescolar , Clostridioides difficile/aislamiento & purificación , Heces/microbiología , Femenino , Gastroenteritis/tratamiento farmacológico , Gastroenteritis/patología , Humanos , Lactante , Masculino , Norovirus/aislamiento & purificación , Estudios Prospectivos , Rotavirus/aislamiento & purificación , Infecciones por Rotavirus/diagnóstico , Infecciones por Rotavirus/tratamiento farmacológico , Salmonella/aislamiento & purificación , Infecciones por Salmonella/diagnóstico , Infecciones por Salmonella/tratamiento farmacológico , Infecciones por Salmonella/microbiología , Taiwán/epidemiología , Resultado del Tratamiento
16.
Proc Natl Acad Sci U S A ; 114(25): 6504-6509, 2017 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-28584107

RESUMEN

Spatial patterning often occurs in ecosystems as a result of a self-organizing process caused by feedback between organisms and the physical environment. Here, we show that the spatial patterns observable in centuries-old Balinese rice terraces are also created by feedback between farmers' decisions and the ecology of the paddies, which triggers a transition from local to global-scale control of water shortages and rice pests. We propose an evolutionary game, based on local farmers' decisions that predicts specific power laws in spatial patterning that are also seen in a multispectral image analysis of Balinese rice terraces. The model shows how feedbacks between human decisions and ecosystem processes can evolve toward an optimal state in which total harvests are maximized and the system approaches Pareto optimality. It helps explain how multiscale cooperation from the community to the watershed scale could persist for centuries, and why the disruption of this self-organizing system by the Green Revolution caused chaos in irrigation and devastating losses from pests. The model shows that adaptation in a coupled human-natural system can trigger self-organized criticality (SOC). In previous exogenously driven SOC models, adaptation plays no role, and no optimization occurs. In contrast, adaptive SOC is a self-organizing process where local adaptations drive the system toward local and global optima.


Asunto(s)
Oryza/fisiología , Evolución Biológica , Ecología , Ecosistema , Retroalimentación , Humanos , Indonesia
17.
Singapore Med J ; 56(11): 612-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26668405

RESUMEN

INTRODUCTION: This study aimed to describe the demographic, social, developmental and behavioural profile of children hospitalised for alleged child maltreatment syndrome (CMS). METHODS: This study was a retrospective review of the consecutive inpatient records of children (0-16 years) admitted to the National University Hospital, Singapore, for alleged CMS over a three-year period. Descriptive data on the demographic characteristics, alleged maltreatment, medical and developmental histories, and family background of these children were collected and analysed. Chi-square statistics were used to test whether family factors were associated with the type of maltreatment and the presence of developmental disorders. RESULTS: A total of 89 children, who accounted for 90 admission cases, were studied. Physical abuse (70.0%) was the most common, followed by neglect (11.1%) and sexual abuse (7.8%). Child protection services had already been involved in 29.2% of the cases prior to the child's admission. Children who were victims of abuse were more likely to come from homes with a prior history of domestic violence (p = 0.028). Financial difficulty was found to be a risk factor for neglect (p = 0.005). Among the 89 children, 15.7% were found to have developmental disorders and 10.1% had mental health diagnoses. Children who had developmental disorders were more likely to have a parent with a mental health disorder (p = 0.002). CONCLUSION: A sizeable proportion of the children admitted for alleged CMS had developmental or behavioural disorders. Clinicians have a role in ensuring that these children have appropriate follow-up plans. Children from high-risk families should be screened for maltreatment.


Asunto(s)
Maltrato a los Niños/estadística & datos numéricos , Niño Abandonado/estadística & datos numéricos , Niño Institucionalizado/estadística & datos numéricos , Niños Huérfanos/estadística & datos numéricos , Discapacidades del Desarrollo/epidemiología , Pacientes Internos/estadística & datos numéricos , Adolescente , Niño , Preescolar , Discapacidades del Desarrollo/etiología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Pobreza , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Singapur/epidemiología
18.
Artículo en Inglés | MEDLINE | ID: mdl-26172751

RESUMEN

The coupling between social and ecological system has become more ubiquitous and predominant in the current era. The strong interaction between these systems can bring about regime shifts which in the extreme can lead to the collapse of social cooperation and the extinction of ecological resources. In this paper, we study the occurrence of such regime shifts in the context of a coupled social-ecological system where social cooperation is established by means of sanction that punishes local selfish act and promotes norms that prescribe nonexcessive resource extraction. In particular, we investigate the role of social networks on social-ecological regimes shift and the corresponding hysteresis effects caused by the local ostracism mechanism under different social and ecological parameters. Our results show that a lowering of network degree reduces the hysteresis effect and also alters the tipping point, which is duly verified by our numerical results and analytical estimation. Interestingly, the hysteresis effect is found to be stronger in scale-free network in comparison with random network even when both networks have the same average degree. These results provide deeper insights into the resilience of these systems, and can have important implications on the management of coupled social-ecological systems with complex social interactions.

19.
Singapore medical journal ; : 612-617, 2015.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-276745

RESUMEN

<p><b>INTRODUCTION</b>This study aimed to describe the demographic, social, developmental and behavioural profile of children hospitalised for alleged child maltreatment syndrome (CMS).</p><p><b>METHODS</b>This study was a retrospective review of the consecutive inpatient records of children (0-16 years) admitted to the National University Hospital, Singapore, for alleged CMS over a three-year period. Descriptive data on the demographic characteristics, alleged maltreatment, medical and developmental histories, and family background of these children were collected and analysed. Chi-square statistics were used to test whether family factors were associated with the type of maltreatment and the presence of developmental disorders.</p><p><b>RESULTS</b>A total of 89 children, who accounted for 90 admission cases, were studied. Physical abuse (70.0%) was the most common, followed by neglect (11.1%) and sexual abuse (7.8%). Child protection services had already been involved in 29.2% of the cases prior to the child's admission. Children who were victims of abuse were more likely to come from homes with a prior history of domestic violence (p = 0.028). Financial difficulty was found to be a risk factor for neglect (p = 0.005). Among the 89 children, 15.7% were found to have developmental disorders and 10.1% had mental health diagnoses. Children who had developmental disorders were more likely to have a parent with a mental health disorder (p = 0.002).</p><p><b>CONCLUSION</b>A sizeable proportion of the children admitted for alleged CMS had developmental or behavioural disorders. Clinicians have a role in ensuring that these children have appropriate follow-up plans. Children from high-risk families should be screened for maltreatment.</p>


Asunto(s)
Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Maltrato a los Niños , Niño Abandonado , Niño Institucionalizado , Niños Huérfanos , Discapacidades del Desarrollo , Epidemiología , Estudios de Seguimiento , Pacientes Internos , Pobreza , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Singapur , Epidemiología
20.
Artículo en Inglés | MEDLINE | ID: mdl-24229160

RESUMEN

The location and nature of the percolation transition in random networks is a subject of intense interest. Recently, a series of graph evolution processes have been introduced that lead to discontinuous percolation transitions where the addition of a single edge causes the size of the largest component to exhibit a significant macroscopic jump in the thermodynamic limit. These processes can have additional exotic behaviors, such as displaying a "Devil's staircase" of discrete jumps in the supercritical regime. Here we investigate whether the location of the largest jump coincides with the percolation threshold for a range of processes, such as Erdos-Rényipercolation, percolation via edge competition and via growth by overtaking. We find that the largest jump asymptotically occurs at the percolation transition for Erdos-Rényiand other processes exhibiting global continuity, including models exhibiting an "explosive" transition. However, for percolation processes exhibiting genuine discontinuities, the behavior is substantially richer. In percolation models where the order parameter exhibits a staircase, the largest discontinuity generically does not coincide with the percolation transition. For the generalized Bohman-Frieze-Wormald model, it depends on the model parameter. Distinct parameter regimes well in the supercritical regime feature unstable discontinuous transitions-a novel and unexpected phenomenon in percolation. We thus demonstrate that seemingly and genuinely discontinuous percolation transitions can involve a rich behavior in supercriticality, a regime that has been largely ignored in percolation.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...