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1.
Oecologia ; 204(1): 95-105, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38123786

RESUMEN

Understanding the circumstances under which insect herbivores will adopt a novel host plant is a longstanding question in basic and applied ecology. While geographic variation in host use can arise through differences in both herbivore preference and plant characteristics, there is a tendency to attribute geographic variation in host use to regional differences in herbivore preference alone. This is especially true for herbivores specialized to one or a few plant species. We compared how geographic variation in herbivore preference and host plant origin shape regional differences in host plant use by the specialized herbivore, Euphydryas phaeton. In parts of its range, E. phaeton uses only a native host, Chelone glabra, while in others, it also uses an introduced host, Plantago lanceolata. We offered female butterflies from each region the non-native host plant sourced from both regions and compared their oviposition behavior. The non-native host was almost universally rejected by butterflies in the region where only the native plant is used. In the region where butterflies use both hosts, females accepted non-native plants from their natal region twice as often as non-native plants from the other region where they are not used. Acceptance differed substantially among individual butterflies within regions but not among plants within regions. Thus, both individual preference and regional differences in both the insect and non-native host contributed to the geographic variation in different ways. These results highlight that, in addition to herbivore preference, regional differences in perceived plant suitability may be an important driver of diet breadth.


Asunto(s)
Mariposas Diurnas , Animales , Femenino , Herbivoria , Larva , Plantas , Dieta , Oviposición
2.
Neurol Sci ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38740728

RESUMEN

BACKGROUND: Drug-resistant juvenile myoclonic epilepsy (DR-JME) remains a significant challenge in neurology. Traditional management strategies often fail to achieve satisfactory control, necessitating innovative treatments. OBJECTIVE: This case report aims to evaluate the efficacy and safety of deep brain stimulation (DBS) targeting the subthalamic nucleus (STN-DBS) in a patient with DR-JME. METHODS: We describe the treatment of a patient with DR-JME using STN-DBS. The patient underwent implantation and received high-frequency stimulation (HFS) at the STN. RESULTS: One year post-implantation, the patient demonstrated a substantial reduction in motor seizure frequency by 87.5%, with improvements in quality of life and seizure severity by 52.0% and 46.7%, respectively. No adverse events were reported during the follow-up period. CONCLUSIONS: This case represents the first report of favorable outcomes with STN-DBS in a patient with DR-JME, suggesting that long-term HFS of the STN may be a promising treatment option for patients suffering from this condition.

3.
Int J Neurosci ; : 1-15, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38738512

RESUMEN

OBJECTIVE: Inflammatory pain, is caused by lesions or diseases of the somatosensory tissue, is a prevalent chronic condition that profoundly impacts the quality of life. However, clinical treatment for this type of pain remains limited. Traditionally, the stimulation of microglia and subsequent inflammatory reactions are considered crucial elements to promote the worsening of inflammatory pain. Recent research has shown the crucial importance of the cGAS-STING pathway in promoting inflammation. It is still uncertain if the cGAS-STING pathway plays the role in the fundamental cause of inflammatory pain. We aim to explore the treatment of inflammatory pain by interfering with cGAS-STING signaling pathway. METHODS: In this study, we established an inflammatory pain model by CFA into the plantar of mice. Activation of microglia, various inflammatory factors and cGAS-STING protein in the spinal dorsal horn were evaluated. Immunofluorescence staining was used to observe the cellular localization of cGAS and STING. The cGAS-STING pathway proteins expression and mRNA expression of indicated microglial M1/M2 phenotypic markers in the BV2 microglia were detected. STING inhibitor C-176 was intrathecal injected into mice with inflammatory pain, and the pain behavior and microglia were observed. RESULTS: This research showed that injecting CFA into the left hind paw of mice caused mechanical allodynia and increased inflammation in the spine. Our research results suggested that the cGAS-STING pathway had a function in the inflammation mediated by microglia in the spinal cord dorsal horn. Blocking the cGAS-STING pathway using STING antagonists (C-176) led to reduced release of inflammatory factors and prevented M1 polarization of BV2 microglia in a laboratory setting. Additionally, intrathecal administration of C-176 reduced the allodynia in CFA treated mice. CONCLUSION: Our results suggest that inhibiting microglial polarization through the cGAS-STING pathway represents a potential novel therapeutic strategy for inflammatory pain.

4.
Pediatr Res ; 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057575

RESUMEN

BACKGROUND: The impact of asthma on the severity of rhinitis when children with allergic rhinitis (AR) are exposed to air pollutants has not been studied. METHODS: Children with AR (65 with asthma, 208 without asthma), aged 6-13 years, were recruited from a hospital in Taichung, Taiwan, between 2007 and 2011. Correlations between Pediatric-Rhinoconjunctivitis-Quality-of-Life score, nasal peak expiratory flow, and air pollutants were compared. With the same age, research time, and form the same city, children with AR (660 with asthma, 3174 without asthma) were selected from a database. Correlations between clinical visit times for AR and air pollutants were compared. RESULTS: In male children with AR and asthma, both clinical and database studies revealed a correlation between higher rhinitis discomfort (quality-of-life score), higher visit times for AR, and higher PM10, PM2.5, NO2, NMHC concentrations. Correlations between higher nasal inflammation/obstruction (lower expiratory flow) and higher air pollutant concentrations were observed in male children with AR and asthma. CONCLUSION: In children with AR, comorbid asthma was associated with increased rhinitis severity when they were exposed to air pollutants, and the association was only noted in males. Increased nasal obstruction/inflammation from exposure to air pollutants may be the mechanisms underlying this association. IMPACT STATEMENT: The influence of asthma on the severity of rhinitis when children with allergic rhinitis (AR) are exposed to air pollutants has not been studied. In children with AR, the correlation between higher rhinitis discomfort, higher number of clinical visits for AR, and higher PM10, PM2.5, NO2, NMHC concentrations were only noted in those who also had asthma. The correlation was only noted in male. Comorbid asthma was associated with higher rhinitis severity when children with AR are exposed to air pollutants The association was only noted in male.

5.
Biochem Biophys Res Commun ; 625: 75-80, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-35952610

RESUMEN

Activating primary afferent TRPV1-positive (TRPV1+) fibers in the spinal dorsal horn triggers exaggerated glutamate release and induces acute pain. However, whether the glutamate postsynaptic responses on dorsal horn neurons are regulated by excessive glutamate is unknown, largely due to intrinsic technical difficulties. In the present study, capsaicin, a specific TRPV1 agonist, was used to activate TRPV1+ fibers in the spinal dorsal horn. Combining three-dimensional (3-D) holographic photostimulation and whole-cell recordings on acute spinal cord slices from adult rodents, we found that postsynaptic glutamate responses were attenuated when activating TRPV1+ fibers with capsaicin. Electron microscopy and Western blot studies found that postsynaptic GluA1 (a subtype of ionotropic glutamate receptors) on the postsynaptic membrane was decreased by acute capsaicin treatment. Therefore, postsynaptic glutamate receptor occupancy and/or downmodulation may underlie this postsynaptic attenuation. Our data thus clarify a scenario in which postsynaptic glutamate responses are largely downregulated upon TRPV1+ activation, and this change may contribute to homeostasis in the dorsal horn circuit when "acute pain" occurs.


Asunto(s)
Capsaicina , Ácido Glutámico , Animales , Capsaicina/farmacología , Potenciales Postsinápticos Excitadores , Dolor , Ratas , Ratas Sprague-Dawley , Médula Espinal/metabolismo , Asta Dorsal de la Médula Espinal/metabolismo , Transmisión Sináptica , Canales Catiónicos TRPV/metabolismo
6.
J Pediatr ; 242: 99-105.e4, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34687690

RESUMEN

OBJECTIVE: To evaluate the association between maternal ambient pollutant exposure and neonatal jaundice in multiple pollutant species and examine sex differences. STUDY DESIGN: Epidemiologic study: Records of 13 297 newborns (6153 male, 7144 female) born in Taichung, Taiwan were obtained from a national database. Average concentrations of prenatal air pollutants 3 months prior to birth were divided into low, middle, and high levels. Neonatal jaundice phototherapy rates between mothers who suffered varying air pollutant levels were compared. Clinical study: Three hundred seventy-six newborns (189 male, 187 female) born and received jaundice treatment with phototherapy in a hospital in Taichung, Taiwan were recruited. The correlation between prenatal exposure to air pollutants 3 months prior to birth, newborn's serum bilirubin, and serum hemoglobin were calculated. RESULTS: Epidemiologic study: Male newborns born to mothers exposed to high carbon monoxide (CO), nitric oxide (NO), nitrogen dioxide (NO2), and methane (CH4) levels had higher phototherapy rates. In female newborns, the same was noted for CO and CH4. Clinical study: Male newborns had a positive correlation between CO, ≤2.5 µm diameter particles, ≤10 µm diameter particles, NO, NO2, nonmethane hydrocarbon, and CH4 exposure 3 months prior to birth and serum bilirubin levels. Female newborns had a positive correlation for CH4. A positive correlation between CO, ≤2.5 µm diameter particles, ≤10 µm diameter particles, NO2, nonmethane hydrocarbon, CH4 exposure, and serum hemoglobin levels was noted in male newborns. CONCLUSION: Maternal exposure to air pollutants may increase neonatal jaundice treatment rates for phototherapy and higher neonatal serum total bilirubin level. Higher hemoglobin levels because of higher pollutant exposures may explain our findings. The association was more obvious in male newborns.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Hiperbilirrubinemia Neonatal , Ictericia Neonatal , Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/efectos adversos , Bilirrubina/sangre , Femenino , Humanos , Hiperbilirrubinemia Neonatal/epidemiología , Hiperbilirrubinemia Neonatal/etiología , Hiperbilirrubinemia Neonatal/terapia , Recién Nacido , Ictericia Neonatal/epidemiología , Ictericia Neonatal/terapia , Masculino , Exposición Materna/efectos adversos , Óxido Nítrico , Dióxido de Nitrógeno/análisis , Embarazo , Estudios Retrospectivos
7.
Phys Rev Lett ; 128(8): 081602, 2022 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-35275652

RESUMEN

We present a new infinite class of gravitational observables in asymptotically anti-de Sitter space living on codimension-one slices of the geometry, the most famous of which is the volume of the maximal slice. We show that these observables display universal features for the thermofield-double state: they grow linearly in time at late times and reproduce the switchback effect in shock wave geometries. We argue that any member of this class of observables is an equally viable candidate as the extremal volume for a gravitational dual of complexity.

8.
Nat Immunol ; 10(5): 496-503, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19329997

RESUMEN

The innate immune response of airway epithelial cells to airborne allergens initiates the development of T cell responses that are central to allergic inflammation. Although proteinase allergens induce the expression of interleukin 25, we show here that epithelial matrix metalloproteinase 7 (MMP7) was expressed during asthma and was required for the maximum activity of interleukin 25 in promoting the differentiation of T helper type 2 cells. Allergen-challenged Mmp7(-/-) mice had less airway hyper-reactivity and production of allergic inflammatory cytokines and higher expression of retinal dehydrogenase 1. Inhibition of retinal dehydrogenase 1 restored the asthma phenotype of Mmp7(-/-) mice and inhibited the responses of lung regulatory T cells, whereas exogenous administration of retinoic acid attenuated the asthma phenotype. Thus, MMP7 coordinates allergic lung inflammation by activating interleukin 25 while simultaneously inhibiting retinoid-dependent development of regulatory T cells.


Asunto(s)
Asma/metabolismo , Interleucinas/metabolismo , Metaloproteinasa 7 de la Matriz/metabolismo , Mucosa Respiratoria/metabolismo , Tretinoina/metabolismo , Alérgenos/inmunología , Animales , Asma/inmunología , Asma/patología , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/inmunología , Diferenciación Celular/inmunología , Cromatografía Líquida de Alta Presión , Citocinas/biosíntesis , Citocinas/inmunología , Modelos Animales de Enfermedad , Electroforesis en Gel Bidimensional , Humanos , Inmunohistoquímica , Interleucinas/inmunología , Activación de Linfocitos/inmunología , Metaloproteinasa 7 de la Matriz/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteómica , Mucosa Respiratoria/inmunología , Retinal-Deshidrogenasa/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Th2/citología , Células Th2/inmunología , Tretinoina/inmunología
9.
Am J Perinatol ; 38(11): 1142-1149, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-32446254

RESUMEN

OBJECTIVE: Bronchopulmonary dysplasia (BPD) is a complex chronic lung disease that primarily affects premature or critically ill infants. This pilot study investigated early changes in gut microbiota composition in BPD patients and explored the potential risk factors associated with these changes. STUDY DESIGN: Preterm infants admitted to our neonatal intensive care unit with a gestational age of 26 to 32 weeks were prospectively surveyed and eligible for stool collection on days 7 and 28 of postnatal age between February 2016 and June 2017. A 16S rRNA sequencing approach was applied to compare the gut microbiota composition between the BPD group and controls. Multiple linear regression analysis was used to identify the predictor variables. RESULTS: Eight subjects in the BPD group and 10 subjects in the preterm group were analyzed during the observation period. Actinobacteria, Proteobacteria, Bacteroidetes, and Firmicutes were the four dominant bacteria phyla of intestinal microflora. A significantly lower diversity of gut microbiota was observed in the BPD group compared with the preterm group on day 28 (number of observed operational taxonomic units, p = 0.034; abundance-based coverage estimator, p = 0.022; Shannon index, p = 0.028). Multiple linear regression analysis revealed that high Neonatal Therapeutic Intervention Scoring System score (≧19) at 24 hours was statistically significant in predicting the proportion of aerobic with facultative anaerobic bacteria on day 28 (p = 0.002). CONCLUSION: Infants with BPD are prone to develop gut dysbiosis in early life. A higher severity of illness and treatment intensity may indicate a higher risk of disrupting an anaerobic environment in the gut during the first month of life. KEY POINTS: · BPD patients are prone to develop gut dysbiosis.. · Lower diversity of gut microbiota.. · Higher risk of disrupting anaerobic environment..


Asunto(s)
Displasia Broncopulmonar/microbiología , Disbiosis/complicaciones , Microbioma Gastrointestinal/genética , Bacterias/clasificación , Estudios de Casos y Controles , Disbiosis/genética , Heces/microbiología , Femenino , Edad Gestacional , Humanos , Recién Nacido , Recien Nacido Prematuro , Unidades de Cuidado Intensivo Neonatal , Modelos Lineales , Masculino , Proyectos Piloto , ARN Ribosómico 16S/genética
10.
Ann Plast Surg ; 86(2): 233-236, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33449468

RESUMEN

ABSTRACT: Oncoplastic breast-conserving surgery for breast cancer has been continuously developing in recent years, and it has become an important part of breast cancer surgery. Its safety and aesthetics have been widely recognized by domestic and foreign experts. However, due to the complexity and diversity of individuals and diseases, and the need for integrating the thinking of breast surgery and plastic surgery, it is still a challenge for breast surgeons. This review summarizes the pros and cons of its clinical application through a comprehensive discussion of hot issues in oncoplastic breast-conserving surgery and introduces common volume-displacement techniques in the clinic for reference by doctors in daily work.


Asunto(s)
Neoplasias de la Mama , Mamoplastia , Mama , Neoplasias de la Mama/cirugía , Humanos , Mastectomía , Mastectomía Segmentaria
11.
Mol Cancer ; 19(1): 96, 2020 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-32460771

RESUMEN

Gastric cancer is a deadly disease and remains the third leading cause of cancer-related death worldwide. The 5-year overall survival rate of patients with early-stage localized gastric cancer is more than 60%, whereas that of patients with distant metastasis is less than 5%. Surgical resection is the best option for early-stage gastric cancer, while chemotherapy is mainly used in the middle and advanced stages of this disease, despite the frequently reported treatment failure due to chemotherapy resistance. Therefore, there is an unmet medical need for identifying new biomarkers for the early diagnosis and proper management of patients, to achieve the best response to treatment. Long non-coding RNAs (lncRNAs) in body fluids have attracted widespread attention as biomarkers for early screening, diagnosis, treatment, prognosis, and responses to drugs due to the high specificity and sensitivity. In the present review, we focus on the clinical potential of lncRNAs as biomarkers in liquid biopsies in the diagnosis and prognosis of gastric cancer. We also comprehensively discuss the roles of lncRNAs and their molecular mechanisms in gastric cancer chemoresistance as well as their potential as therapeutic targets for gastric cancer precision medicine.


Asunto(s)
Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/genética , Resistencia a Antineoplásicos/genética , ARN no Traducido/metabolismo , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/tratamiento farmacológico , Animales , Progresión de la Enfermedad , Humanos , Medicina de Precisión , ARN no Traducido/genética , Neoplasias Gástricas/genética
12.
BMC Cancer ; 20(1): 136, 2020 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-32085753

RESUMEN

BACKGROUND: The benefit of adjuvant chemotherapy in invasive lobular carcinoma (ILC) is still unclear. The objective of the current study was to elucidate the effectiveness of adjuvant chemotherapy in hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative, pT1b-c/N0-1/M0 ILC. METHODS: Based on Surveillance, Epidemiology, and End-Results (SEER) database, we identified original 12,334 HR-positive, HER2-negative, pT1b-c/N0-1/M0 ILC patients, who were then divided into adjuvant chemotherapy group and control group. End-points were overall survival (OS) and breast cancer-specific mortality (BCSM). Aiming to minimize the selection bias of baseline characteristics, Propensity Score Matching (PSM) method was used. RESULTS: In a total of 12,334 patients with HR-positive, HER2-negative, pT1b-c/N0-1/M0 ILC, 1785 patients (14.5%) were allocated into adjuvant chemotherapy group and 10,549 (85.5%) into control group. Used PSM, the 1785 patients in adjuvant chemotherapy group matched to the 1785 patients in control group. By Kaplan-Meier survival analyses, we observed no beneficial effect of adjuvant chemotherapy on OS in both original samples (P = 0.639) and matched samples (P = 0.962), however, ineffective or even contrary results of adjuvant chemotherapy on BCSM both in original samples (P = 0.001) and in matched samples (P = 0.002). In both original and matched multivariate Cox models, we observed ineffectiveness of adjuvant chemotherapy on OS (hazard ratio (HR) for overall survival = 0.82, 95% confidence interval (CI) [0.62-1.09]; P = 0.172 and HR = 0.90, 95%CI [0.65-1.26]; P = 0.553, respectively), unexpectedly promoting effect of adjuvant chemotherapy on BCSM (HR = 2.33, 95%CI [1.47-3.67]; P = 0.001 and HR = 2.41, 95%CI [1.32-4.39]; P = 0.004, respectively). Standard surgery was beneficial to the survival of patients. Lymph node metastasis was detrimental to survival and radiotherapy brought survival benefit in original samples, but two issues had unobvious effect in matched samples. CONCLUSION: In this study, adjuvant chemotherapy did not improve survival for patients with HR-positive, HER2-negative pT1b-c/N0-1/M0 ILC.


Asunto(s)
Neoplasias de la Mama/mortalidad , Quimioterapia Adyuvante/mortalidad , Receptor alfa de Estrógeno/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Progesterona/metabolismo , Programa de VERF/estadística & datos numéricos , Adulto , Anciano , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Carcinoma Lobular/tratamiento farmacológico , Carcinoma Lobular/mortalidad , Carcinoma Lobular/patología , Quimioterapia Adyuvante/métodos , Femenino , Humanos , Metástasis Linfática , Persona de Mediana Edad , Estadificación de Neoplasias , Puntaje de Propensión , Tasa de Supervivencia
13.
Environ Res ; 184: 109301, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32120124

RESUMEN

Forced-draft biomass stoves improve the pollutant emission performance of biomass combustion. The parameters of supply airflow and its distribution between primary air (PA) and secondary air (SA) have a significant effect on the performance of this stove type. In this study, we designed an air supply control system to accurately quantify the airflow rates, and monitored the dynamic emissions of focused pollutant species including carbon monoxide (CO), nitrogen oxides (NOx), particulate matter (PM2.5), and the fuel burning rate. The tested stove had a combustion structure typical of many popular stoves, and wood pellets were the burning fuel. Three total airflow rates (92 L/min, 184 L/min, and 276 L/min) were selected, and six distributions between PA and SA (PA:SA) for each airflow rate were tested, which included 10:0 (full PA), 8:2, 6:4, 5:5, 4:6, and 2:8. The results showed that the test duration, burning rate, and pollutant (CO, NOx, and PM2.5) emission performances of different airflows or distributions varied. Overall, when the PA and SA distribution mode was determined, the total airflow rate of 184 L/min was the optimal supply airflow rate. Under the same total airflow rate, the burning and emission performances were better when the primary and secondary airflows were similar, namely from 4:6 to 6:4. This study provided core information about stove air supply and distribution, which is essential to quantitatively determine the stove air supply mode to significantly improve stove performances.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Artículos Domésticos , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Biomasa , Culinaria , Material Particulado/análisis , Madera/química
14.
Indoor Air ; 30(2): 294-305, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31880849

RESUMEN

Biomass combustion for cooking and heating releases particulate matter (PM2.5 ) that contributes to household air pollution. Fuel and stove types affect the chemical composition of household PM, as does infiltration of outdoor PM. Characterization of these impacts can inform future exposure assessments and epidemiologic studies, but is currently limited. In this study, we measured chemical components of PM2.5 (water-soluble organic matter [WSOM], ions, black carbon, elements, organic tracers) in rural Chinese households using traditional biomass stoves, semi-gasifier stoves with pelletized biomass, and/or non-biomass stoves. We distinguished households using one stove type (traditional, semi-gasifier, or LPG/electric) from those using multiple stoves/fuels. WSOM concentrations were higher in households using only semi-gasifier or traditional stoves (31%-33%) than in those with exclusive LPG/electric stove (13%) or mixed stove use (12%-22%). Inorganic ions comprised 14% of PM in exclusive LPG/electric households, compared to 1%-5% of PM in households using biomass. Total PAH content was much higher in households that used traditional stoves (0.8-2.8 mg/g PM) compared to those that did not (0.1-0.3 mg/g PM). Source apportionment revealed that biomass burning comprised 27%-84% of PM2.5 in households using biomass. In all samples, identified outdoor sources (vehicles, dust, coal combustion, secondary aerosol) contributed 10%-20% of household PM2.5 .


Asunto(s)
Contaminación del Aire Interior/análisis , Culinaria , Exposición a Riesgos Ambientales/análisis , Contaminación del Aire , Contaminación del Aire Interior/estadística & datos numéricos , Composición Familiar , Calefacción , Artículos Domésticos , Humanos , Material Particulado/análisis , Población Rural , Hollín
15.
Indoor Air ; 30(3): 521-533, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31943353

RESUMEN

Monitoring improved cookstove adoption and usage in developing countries can help anticipate potential health and environmental benefits that may result from household energy interventions. This study explores stove-usage monitor (SUM)-derived usage data from field studies in China (52 stoves, 1422 monitoring days), Honduras (270 stoves, 630 monitoring days), India (19 stoves, 565 monitoring days), and Uganda (38 stoves, 1007 monitoring days). Traditional stove usage was found to be generally similar among four seemingly disparate countries in terms of cooking habits, with average usage of between 171 and 257 minutes per day for the most-used stoves. In Honduras, where survey-based usage data were also collected, there was only modest agreement between sensor data and self-reported user data. For Indian homes, we combined stove-usage data with a single-zone Monte Carlo box model to estimate kitchen-level PM2.5 and CO concentrations under various scenarios of cleaner cookstove adoption. We defined clean cookstove performance based on the International Standards Organization (ISO) voluntary guidelines. Model results showed that even with 75% displacement of traditional stoves with the cleanest available stove (ISO tier-5), World Health Organization 24 hours PM2.5 standards were exceeded in 96.4% of model runs, underscoring the importance of full displacement.


Asunto(s)
Contaminación del Aire Interior , Culinaria , China , Composición Familiar , Honduras , Artículos Domésticos , Productos Domésticos , Humanos , India , Material Particulado , Población Rural , Uganda
16.
Sci Eng Ethics ; 26(1): 325-349, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-30868376

RESUMEN

Construction process stages are argued to be vulnerable to the prevalence of corrupt practices. However, the validity of this argument has not been empirically explored in the extant literature of construction management. Therefore, this study examines the stages of the construction process susceptibility to corruption and its most prominent forms of corrupt activities (within the respective stages). A total of forty-four project-related professionals were involved in an expert survey to assess such susceptibilities and the criticality of the identified corrupt activities at each stage. A comparative study of expert views from developing regions against experts from developed regions is conducted. Expert scoring results revealed that three stages are most susceptible, namely: project execution, pre-qualification and tender stages. Such results were confirmed by application of the Mann-Whitney U test statistics tool, showing wide disparities in seven out of eleven identical stages. This study is intended to incite polemic discussions and greater empirical, evidence-based research from scholars in both developed and developing countries. This study adds to the extant literature corruption-related works on the construction process through deeper understanding of the dynamic nature of corrupt practices involved in the stages of the construction process in developing countries. Practically, it intends to offer a veritable plethora of information on the critical stages of the construction process for industry practitioners, policymakers and anti-corruption bodies to careen their attention towards the fight against corruption.


Asunto(s)
Industria de la Construcción/ética , Industria de la Construcción/organización & administración , Crimen , Mala Conducta Profesional , Industria de la Construcción/legislación & jurisprudencia , Países Desarrollados , Países en Desarrollo , Investigación Empírica , Humanos , Incidencia , Prevalencia , Encuestas y Cuestionarios
17.
Phys Rev Lett ; 123(8): 081601, 2019 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-31491207

RESUMEN

We investigate the variation of holographic complexity for two nearby target states. Based on Nielsen's geometric approach, we find the variation only depends on the end point of the optimal trajectory, a result which we designate the first law of complexity. As an example, we examine the complexity=action conjecture when the anti-de Sitter vacuum is perturbed by a scalar field excitation, which corresponds to a coherent state. Remarkably, the gravitational contributions completely cancel and the final variation reduces to a boundary term coming entirely from the scalar field action. Hence, the null boundary of Wheeler-DeWitt patch appears to act like the "end of the quantum circuit".

18.
Environ Sci Technol ; 53(5): 2788-2798, 2019 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-30696246

RESUMEN

The chemical constituents of fine particulate matter (PM2.5) vary by source and capacity to participate in redox reactions in the body, which produce cytotoxic reactive oxygen species (ROS). Knowledge of the sources and components of PM2.5 may provide insight into the adverse health effects associated with the inhalation of PM2.5 mass. We collected 48 h household and personal PM2.5 exposure measurements in the summer months among 50 women/household pairs in a rural area of southwestern China where daily household biomass burning is common. PM2.5 mass was analyzed for ions, trace metals, black carbon, and water-soluble organic matter, as well as ROS-generating capability (oxidative potential) by one cellular and one acellular assay. Crustal enrichment factors and a principal component analysis identified the major sources of PM2.5 as dust, biomass burning, and secondary sulfate. Elements associated with the secondary sulfate source (As, Mo, Zn) had the strongest correlation with increased cellular oxidative potential (Spearman r: 0.74, 0.68, and 0.64). Chemical markers of biomass burning (water-soluble potassium and water-soluble organic matter) had negligible oxidative potential, suggesting that these assays may not be useful as health-relevant exposure metrics in populations that are exposed to high levels of smoke from household biomass burning.


Asunto(s)
Contaminantes Atmosféricos , China , Monitoreo del Ambiente , Femenino , Humanos , Oxidación-Reducción , Estrés Oxidativo , Material Particulado
19.
Environ Sci Technol ; 53(15): 9306-9316, 2019 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-31294968

RESUMEN

We evaluated whether an energy package comprising a low-polluting semigasifier cookstove with chimney, water heater, and pelletized biomass fuel would improve air pollution in China. We measured the stove use, 48-h air pollution exposures (PM2.5, black carbon), and kitchen concentrations (PM2.5, black carbon, carbon monoxide, nitrogen oxides) for 205 women, along with ambient PM2.5. Over half (n = 125) were offered the energy package after baseline assessment, forming "treated" and "untreated" groups, and we repeated the measurements up to 3 occasions over 18-months. Kitchen carbon monoxide did not change, and nitrogen oxides increased in summer but decreased in winter for both groups. Summer geometric mean exposures and kitchen concentrations of PM2.5 and black carbon decreased by 24-67% in women who received the energy package, but greater reductions (48-70%) were observed in untreated homes, likely due to increased use of gas stoves. After adjusting for differences in outdoor PM2.5, receiving the energy package was associated with decreased winter exposures to PM2.5 (-46%; 95% CI: -70, -2) and black carbon (-55%; -74, -25) and the summer increases were smaller (PM2.5: 8%; -22, 51 and black carbon: 37%; -12, 113). However, PM2.5 exposures remained 1.5-3 times higher than those of health-based international air pollution targets.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , China , Culinaria , Exposición a Riesgos Ambientales , Monitoreo del Ambiente , Femenino , Humanos , Material Particulado
20.
Sci Eng Ethics ; 25(1): 1-31, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29129014

RESUMEN

The development of efficient and strategic anti-corruption measures can be better achieved if a deeper understanding and identification of the causes of corruption are established. Over the past years, many studies have been devoted to the research of corruption in construction management (CM). This has resulted in a significant increase in the body of knowledge on the subject matter, including the causative factors triggering these corrupt practices. However, an apropos systematic assessment of both past and current studies on the subject matter which is needful for the future endeavor is lacking. Moreover, there is an absence of unified view of the causative factors of corruption identified in construction project management (CPM). This paper, therefore, presents a comprehensive review of the causes of corruption from selected articles in recognized construction management journals to address the mentioned gaps. A total number of 44 causes of corruption were identified from 37 publications and analyzed in terms of existing causal factors of corruption, annual trend of publications and the thematic categorization of the identified variables. The most identifiable causes were over close relationships, poor professional ethical standards, negative industrial and working conditions, negative role models and inadequate sanctions. A conceptual framework of causes of corruption was established, after categorizing the 44 variables into five unique categories. In descending order, the five constructs are Psychosocial-Specific Causes, Organizational-Specific Causes, Regulatory-Specific Causes, Project-Specific Causes and Statutory-Specific Causes. This study extends the current literature of corruption research in construction management and contributes to a deepened understanding of the causal instigators of corruption identified in CPM. The findings from this study provide valuable information and extended knowledge to industry practitioners and policymakers as well as anti-corruption agencies in the formulation and direction of anti-corruption measures. To corruption researchers in CM, this study is vital for further research.


Asunto(s)
Industria de la Construcción/ética , Ética en los Negocios , Ética Profesional , Humanos , Principios Morales
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