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Even with intensive sampling effort, data often remain sparse when estimating population density of elusive species such as the Sunda clouded leopard Neofelis diardi. An inadequate number of recaptures can make it difficult to account for heterogeneity in detection parameters. We used data from large-scale camera-trapping surveys in three forest reserves in Sabah, Malaysian Borneo, to (1) examine whether a high-density camera-trap network increases the number of recaptures for females, which tend to be more difficult to detect, thus improving the accuracy of density estimates; (2) compare density estimates from models incorporating individual heterogeneity in detection parameters with estimates from the null model to evaluate its potential bias; and (3) investigate how the size of the camera-trap grid affects density and movement estimates. We found that individual heterogeneity could not be incorporated in the single-site data analysis and only conservative null model estimates could be generated. However, aggregating data across study sites enabled us to account for individual heterogeneity and we estimated densities of 1.27–2.82 individuals/100 km2, 2–3 times higher than estimates from null models. In light of these findings, it is possible that earlier studies underestimated population density. Similar densities found in well-managed forest and recently selectively logged forest suggest that Sunda clouded leopards are relatively resilient to forest disturbances. Our analysis also revealed that camera-trapping grids for Sunda clouded leopard density estimations should cover large areas (c. 250 km2), although smaller grids could be appropriate if density or detectability are higher.
Tropical forest regions in equatorial Africa are threatened with degradation, deforestation and biodiversity loss as a result of land-cover change. We investigated historical land-cover dynamics in unprotected forested areas of the Littoral Region in south-western Cameroon during 1975–2017, to detect changes that may influence this important biodiversity and wildlife area. Processed Landsat imagery was used to map and monitor changes in land use and land cover. From 1975 to 2017 the area of high-value forest landscapes decreased by c. 420,000 ha, and increasing forest fragmentation caused a decline of c. 12% in the largest patch index. Conversely, disturbed vegetation, cleared areas and urban areas all expanded in extent, by 32% (c. 400,000 ha), 5.6% (c. 26,800 ha) and 6.6% (c. 78,631 ha), respectively. The greatest increase was in the area converted to oil palm plantations (c. 26,893 ha), followed by logging and land clearing (c. 34,838 ha), all of which were the major factors driving deforestation in the study area. Our findings highlight the increasing threats facing the wider Littoral Region, which includes Mount Nlonako and Ebo Forest, both of which are critical areas for regional conservation and the latter a proposed National Park and the only sizable area of intact forest in the region. Intact forest in the Littoral Region, and in particular at Ebo, merits urgent protection.
Eating behaviours in childhood are considered as risk factors for eating disorder behaviours and diagnoses in adolescence. However, few longitudinal studies have examined this association.
We investigated associations between childhood eating behaviours during the first ten years of life and eating disorder behaviours (binge eating, purging, fasting and excessive exercise) and diagnoses (anorexia nervosa, binge eating disorder, purging disorder and bulimia nervosa) at 16 years.
Data on 4760 participants from the Avon Longitudinal Study of Parents and Children were included. Longitudinal trajectories of parent-rated childhood eating behaviours (8 time points, 1.3–9 years) were derived by latent class growth analyses. Eating disorder diagnoses were derived from self-reported, parent-reported and objectively measured anthropometric data at age 16 years. We estimated associations between childhood eating behaviours and eating disorder behaviours and diagnoses, using multivariable logistic regression models.
Childhood overeating was associated with increased risk of adolescent binge eating (risk difference, 7%; 95% CI 2 to 12) and binge eating disorder (risk difference, 1%; 95% CI 0.2 to 3). Persistent undereating was associated with higher anorexia nervosa risk in adolescent girls only (risk difference, 6%; 95% CI, 0 to 12). Persistent fussy eating was associated with greater anorexia nervosa risk (risk difference, 2%; 95% CI 0 to 4).
Our results suggest continuities of eating behaviours into eating disorders from early life to adolescence. It remains to be determined whether childhood eating behaviours are an early manifestation of a specific phenotype or whether the mechanisms underlying this continuity are more complex. Findings have the potential to inform preventative strategies for eating disorders.
Declaration of interest
C.M.B. reports conflict of interest with Shire (grant recipient, Scientific Advisory Board member) and Pearson and Walker (author, royalty recipient). All other authors have indicated they have no conflicts of interest to disclose.
Artificial Neural Networks (ANNs)-based techniques have dominated state-of-the-art results in most problems related to computer vision, audio recognition, and natural language processing in the past few years, resulting in strong industrial adoption from all leading technology companies worldwide. One of the major obstacles that have historically delayed large-scale adoption of ANNs is the huge computational and power costs associated with training and testing (deploying) them. In the mean-time, Neuromorphic Computing platforms have recently achieved remarkable performance running the bio-realistic Spiking Neural Networks at high throughput and very low power consumption making them a natural alternative to ANNs. Here, we propose using the Random Neural Network, a spiking neural network with both theoretical and practical appealing properties, as a general purpose classifier that can match the classification power of ANNs on a number of tasks while enjoying all the features of being a spiking neural network. This is demonstrated on a number of real-world classification datasets.
To investigate a Middle East respiratory syndrome coronavirus (MERS-CoV) outbreak event involving multiple healthcare facilities in Riyadh, Saudi Arabia; to characterize transmission; and to explore infection control implications.
Cases presented in 4 healthcare facilities in Riyadh, Saudi Arabia: a tertiary-care hospital, a specialty pulmonary hospital, an outpatient clinic, and an outpatient dialysis unit.
Contact tracing and testing were performed following reports of cases at 2 hospitals. Laboratory results were confirmed by real-time reverse transcription polymerase chain reaction (rRT-PCR) and/or genome sequencing. We assessed exposures and determined seropositivity among available healthcare personnel (HCP) cases and HCP contacts of cases.
In total, 48 cases were identified, involving patients, HCP, and family members across 2 hospitals, an outpatient clinic, and a dialysis clinic. At each hospital, transmission was linked to a unique index case. Moreover, 4 cases were associated with superspreading events (any interaction where a case patient transmitted to ≥5 subsequent case patients). All 4 of these patients were severely ill, were initially not recognized as MERS-CoV cases, and subsequently died. Genomic sequences clustered separately, suggesting 2 distinct outbreaks. Overall, 4 (24%) of 17 HCP cases and 3 (3%) of 114 HCP contacts of cases were seropositive.
We describe 2 distinct healthcare-associated outbreaks, each initiated by a unique index case and characterized by multiple superspreading events. Delays in recognition and in subsequent implementation of control measures contributed to secondary transmission. Prompt contact tracing, repeated testing, HCP furloughing, and implementation of recommended transmission-based precautions for suspected cases ultimately halted transmission.
Oxidative stress is a major cause of defective embryo development during in vitro culture. Retinoids are recognized as non-enzymatic antioxidants and may have an important role in the regulation of cell differentiation and vertebrate development. However, there are not enough reports discussing the antioxidant and developmental capacity of retinoids, including retinol (RT), on the in vitro development of embryos recovered from livestock animals, particularly in rabbit species. Therefore, morula embryos obtained from nulliparous Red Baladi rabbit does were cultured for 48 h in TCM199 medium in the absence of RT (control group) or in the presence of RT at concentrations of 10, 100 and 1000 nM. The developmental capacity to the hatched blastocyst stage, the antioxidant biomarker assay and the expression of several selected genes were analyzed in each RT group. The data show that RT significantly (P<0.001) promoted the embryo hatchability rate at the concentration of 1000 nM to 69.44% versus 29.71% for the control. The activity of malondialdehyde (MDA) level was significantly (P<0.05) lower in the RT groups than in the control group, while the total antioxidant capacity (TAC), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities were significantly (P<0.05) higher following treatment with RT. Furthermore, RT treatment considerably upregulated the relative expression of gap junction protein alpha 1 (GJA1), POU class 5 homeobox 1 (POU5F1) and superoxide dismutase 1 (SOD1) genes compared with the control group. The current study highlights the potential effects of RT as antioxidant in the culture medium on the in vitro development of rabbit embryos.
Left ventricular assist device implantation is an important therapeutic option for children with end-stage heart failure. However, device-related complications such as infection may occur while the patient is supported. Device-associated infection can be life-threatening, and early detection is critical. F-fluorodeoxyglucose positron emission tomography and CT is a highly sensitive imaging modality for the detection of an inflammatory response and is useful to evaluate the response to antibiotic therapy. We present two case reports of a left ventricular assist device-associated infection detected by F-fluorodeoxyglucose positron emission tomography and CT in children.
Conventional electron microscopy during the last three decades has experienced tremendous developments, especially in equipment design and engineering, to become one of the most widely recognized and powerful tools for key research areas in materials science and nanotechnology. In this article, we discuss scanning ultrafast electron microscopy (S-UEM) as a new methodology for four-dimensional electron imaging of material surfaces. We also illustrate a few unique applications. By monitoring secondary electrons emitted from surfaces of photoactive materials, photo- and electron-impact-induced electrons and holes near surfaces, interfaces, and heterojunctions can be imaged with adequate spatial and temporal resolution. Charge separation, transport, and anisotropic motions as well as their dependence on carrier energies can be resolved. S-UEM is poised to directly image and visualize relevant interfacial dynamics in real space and time for emerging optoelectronic devices and help push their performance.
Wealth index is a known predictor of body mass index (BMI). Many studies have reported a positive association between BMI and socioeconomic status (SES). However, an in-depth investigation of the relationship between BMI and wealth index is lacking for urban slum settings.
To examine the association between BMI and wealth index in an urban slum setting in Nairobi, Kenya.
A total of 2003 adults between 40 and 60 years of age were included. BMI was derived from direct weight and height measurements. Wealth Index was computed using the standard principal component analysis of household amenities ownership. The relationship between BMI and wealth index was assessed using both linear and logistic regression models.
We found that BMI linearly increased across the five quintiles of wealth index in both men and women, after adjusting for potential confounding factors. The prevalence of obesity increased from 10% in the first wealth quintile to 26.2% in the fifth wealth quintile. The average BMI for women entered the overweight category at the second quintile wealth status, or the third quintile for the total population.
There exists a strong positive relationship between BMI and wealth index in slum settings. Health promotion interventions aimed at reducing obesity may consider using wealth index in priority setting.
This work aims to develop simple and cost-effective methods in reduction of Cr(VI) from water to less toxic and easy separated Cr(III) using Titanium dioxide (TiO2).
TiO2 nanoparticles are prepared by a sol-gel method using titanium tetra-chloride and characterized using X-Ray Diffraction (XRD), Scanning electron microscope (SEM), Energy dispersive X-ray Fluorescence spectrometer (EDX) and UV-visible spectroscopy. XRD shows Anatase structure of TiO2 after annealing at 600°C for four hours. The particles size is estimated to be 70 nm using SEM.UV-Visible spectroscopy indicated that TiO2 nanoparticles played important role in decreasing the concentration of Cr (VI) in water samples for different pH range of 1 to 4. The decrease in Cr(VI) concentration after the treatment is ascribed to the reduction caused by the photocatalyst effect that resulted from the presence of TiO2 nanoparticle in water samples under direct exposure to direct sunlight.
Persistence of the embryonic “fifth aortic arch” in postnatal life is a rare, enigmatic – and at times controversial – condition, with variable anatomical forms and physiological consequences. First described in humans over 40 years ago by Van Praagh, the condition was labelled the “great pretender” by Gerlis 25 years later, because of its apparent propensity to mimic anatomically similar structures. Despite many subsequent case reports citing the condition, the true developmental origin of these structures remains unresolved, and has been the subject of debate among embryologists for more than a century. A persistent fifth aortic arch has been defined as an extrapericardial structure, arising from the ascending aorta opposite or proximal to the brachiocephalic artery, and terminating in the dorsal aorta or pulmonary arteries via a persistently patent arterial duct. This description may therefore encompass various anatomical forms, such as a unilateral double-lumen aortic arch, an unrestrictive aortopulmonary shunt, or a critical vascular channel for either the systemic or pulmonary circulation. The physiological properties of these vessels, such as their response to prostaglandins, may also be unpredictable. In this article, we demonstrate a number of cases that fulfil the contemporary definition of “persistent fifth aortic arch” while acknowledging the embryological controversies associated with this term. We also outline the key diagnostic features, particularly with respect to the use of new cross-sectional imaging techniques.
To investigate the role of diagnostic imaging in the clinical diagnosis, treatment, and follow-up management of patients in response to disasters.
A MEDLINE (OVID) search of original research articles identified 177 articles on this topic published since 2000. A bibliometric analysis was conducted on the top 100 articles ranked by average yearly citation.
The most frequently studied disaster categories were disease outbreak (55 articles), armed conflict (23 articles), terrorist incident (10 articles), and earthquake (7 articles). The most studied disasters were the H1N1 influenza outbreak in 2009 (28 articles), Severe Acute Respiratory Syndrome outbreak in 2003 (24 articles), War in Afghanistan, 2001-2014 (8 articles), Iraq War, 2003-2011 (6 articles), and the Sichuan earthquake (China) in 2008 (6 articles). Among the first authors, 59 were primarily affiliated with Radiology. The United States of America produced the most articles (25 articles), followed by the People’s Republic of China (24 articles). Eighty-one studies were retrospective, with 19 studies being prospective. Computed tomography was the most investigated modality (52.8%), followed by conventional radiography (33.3%) and ultrasound (9.7%).
Our study identifies intellectual milestones in the utility of diagnostic imaging in response to various disasters, and could help guide future research in developing disaster management plans. (Disaster Med Public Health Preparedness. 2018;12:265–277)
In the present study a comparison of the otolith morphology of two species of parrotfish, family Scaridae, collected from the Red Sea coast of Egypt, is conducted to identify the most appropriate taxonomic characters that separate these species. Ontogenetic changes in the otoliths of the two scarid fishes become evident. In the otoliths of Chlorurus sordidus, the following characters are comparable in small-sized adult fishes: otolith width, otolith depth, mesial surface shape, lateral surface shape, shape of sulcus acusticus, column, rostrum and size of rostrum. The otoliths of young adults (GI) C. sordidus differ from the adult ones in 14 out of the 22 characteristics studied. In the otoliths of Hipposcarus harid, the following characters are comparable in small and large fish: otolith width, otolith depth, mesial and lateral surface shapes, shape of sulcus acusticus, rostrum and size of rostrum.
A gravitational search algorithm (GSA) is a meta-heuristic development that is modelled on the Newtonian law of gravity and mass interaction. Here we propose a new hybrid algorithm called the Direct Gravitational Search Algorithm (DGSA), which combines a GSA that can perform a wide exploration and deep exploitation with the Nelder-Mead method, as a promising direct method capable of an intensification search. The main drawback of a meta-heuristic algorithm is slow convergence, but in our DGSA the standard GSA is run for a number of iterations before the best solution obtained is passed to the Nelder-Mead method to refine it and avoid running iterations that provide negligible further improvement. We test the DGSA on 7 benchmark integer functions and 10 benchmark minimax functions to compare the performance against 9 other algorithms, and the numerical results show the optimal or near optimal solution is obtained faster.
Top-down biomedical interventions to control schistosomiasis in sub-Saharan Africa have had limited success, primarily because they fail to engage with the social, political, economic and ecological contexts in which they are delivered. Despite the call to foster community engagement and to adapt interventions to local circumstances, programmes have rarely embraced such an approach. This article outlines a community co-designed process, based upon Human-Centered Design, to demonstrate how this approach works in practice. It is based on initial work undertaken by social science researchers, public health practitioners and community members from the Zanzibar Islands, Tanzania, between November 2011 and December 2013. During the process, 32 community members participated in a qualitative and quantitative data-driven workshop where they interpreted data on local infections from S. haematobium and co-designed interventions with the assistance of a facilitator trained in the social sciences. These interventions included the implementation of novel school-based education and training, the identification of relevant safe play activities and events at local schools, the installation of community-designed urinals for boys and girls and the installation of community-designed laundry-washing platforms to reduce exposure to cercariae-contaminated fresh water. It is suggested that the a community co-designed process, drawing from Human-Centered Design principles and techniques, enables the development of more sustainable and effective interventions for the control of schistosomiasis.
This study reports new facile approach for gram-scale synthesis of graphene-like nanosheets fine powder, using glucose as precursor. Reduced graphene oxide (RGO) has been prepared in gram-scale via hydrothermal treatment of glucose. Upon increasing the vapor/liquid ratio for aqueous glucose solution within the autoclave system to 3/2, RGO-rich graphitic powder, containing small graphene oxide and amorphous carbon contents and having spherical morphology, is obtained. Then, introducing ammonia into the reaction medium resulted in the formation of pure RGO with reduced O-content and flat nanosheet-like morphology (Amm–RGO3/2). Interestingly, few-layer graphene-like nanosheets with slight oxygen and amorphous carbon contents and few structural defects are produced when annealing Amm–RGO3/2 at 600 °C under inert atmosphere. In summary, hydrothermal treatment of aqueous solution containing just glucose and ammonia followed by moderate-temperature thermal annealing, lead to few-layer graphene-like nanosheets with good structural characteristics. This new simple and efficient approach can be of great potential in the mass production of graphene-like nanosheets.
A species in the Bactrocera dorsalis (Hendel) complex was detected in Kenya during 2003 and classified as Bactrocera invadens Drew, Tsuruta & White. Having spread rapidly throughout Africa, it threatens agriculture due to crop damage and loss of market access. In a recent revision of the B. dorsalis complex, B. invadens was incorporated into the species B. dorsalis. The potential distribution of B. dorsalis has been previously modelled. However, previous models were based on presence data and did not incorporate information on the seasonal phenology of B. dorsalis, nor on the possible influence that irrigation may have on its distribution. Methyl eugenol-baited traps were used to collect B. dorsalis in Africa. Seasonal phenology data, measured as fly abundance throughout the year, was related to each location's climate to infer climatic growth response parameters. These functions were used along with African distribution records and development studies to fit the niche model for B. dorsalis, using independent global distribution records outside Africa for model validation. Areas at greatest risk of invasion by B. dorsalis are South and Central America, Mexico, southernmost USA, parts of the Mediterranean coast, parts of Southern and Eastern Australia and New Zealand's North Island. Under irrigation, most of Africa and Australia appear climatically suitable.