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This work presents a multimode flight framework control scheme for a quadrotor based on the super twisting algorithm. The controller design stages for six flight control modes are presented. The stability proof for each flight mode is carried out by means of Lyapunov functions, while the stability analysis for the complete control scheme, when a transition from one flight mode to another occurs, is demonstrated using the switching nonlinear systems theory. The performance of the proposed framework is shown in a 3D simulation environment considering a forest fire detection task, which takes into account external disturbances.
Four new actinospore types belonging to the sphaeractinomyxon collective group (Cnidaria, Myxosporea) are described from the coelomic cavity of a marine Baltidrilus sp. (Oligochaeta, Naididae) inhabiting a northern Portuguese estuary. Host identification supports the usage of marine oligochaetes, namely of the family Naididae Ehrenberg, 1828, as definitive hosts for myxosporeans inhabiting estuarine/marine environments. The absence of mixed infections in the host specimens analysed is suggested to reflect the influence of host-, parasite- and environmental-related factors regulating myxosporean–annelid interactions. Molecular analyses matched the SSU rDNA sequences of three of the four new types with those of mugiliform-infecting Myxobolus spp., namely Myxobolus mugiliensis and a Myxobolus sp. from flathead grey mullet Mugil cephalus, and Myxobolus labrosus from thicklip grey mullet Chelon labrosus. These results directly link, for the first time, the sphaeractinomyxon collective group to a myxospore counterpart, further confirming their previously hypothesized specific involvement in the life cycle of myxobolids that infect mullets. Acknowledging this life cycle relationship, the functionality of the sphaeractinomyxon morphotype is suggested to have been decisive for the evolutionary hyperdiversification of the genus Myxobolus in mullets. Unlike other actinospore morphotypes, sphaeractinomyxon lack valvular processes, which implies a limited capability for buoyancy. Considering the benthic-feeding nature of mullets, this feature is most likely crucial in promoting successful transmission to the vertebrate host.
Maternal obesity (MO) during pregnancy and lactation leads to maternal and offspring metabolic dysfunction. Recent research has suggested that probiotics might be a novel approach to counteract these unwanted MO effects. The aim of this research was to analyze the impact of Leuconostoc SD23, a probiotic isolated from aguamiel (traditional Mexican drink), on MO metabolism in rats at the end of lactation (21 days). From weaning through lactation, control female Wistar rats (C) ate chow (5% fat) or high-energy obesogenic diet (MO; 25% fat). Half the C and MO mothers received a daily dose (1 × 1010 CFU/ml) of probiotic orally, control with probiotic (CP) and MO with probiotic (MOP), 1 month before mating and through pregnancy and lactation. Histological analyses of the liver, white adipose tissue and small intestine, body composition, glucose, insulin, triglycerides, and leptin were determined in mothers at the end of lactation. Maternal weight during pregnancy was greater in MO than C mothers, but similar at the end of lactation. Probiotic intervention had no effect on maternal weight. However, at the end of lactation, percentage of body fat was higher in MO than C, CP, and MOP. Serum glucose, homeostasis model assessment of insulin resistance, and triglycerides were higher in MO versus C, CP, and MOP. MO small intestine villus height was higher versus MOP, C, and CP. Leuconostoc SD23 did not present adverse effects in C. Conclusions: maternal administration of Leuconostoc SD23 has beneficial effects on maternal metabolism, which holds possibilities for preventing adverse offspring metabolic programming.
We present a detailed overview of the cosmological surveys that we aim to carry out with Phase 1 of the Square Kilometre Array (SKA1) and the science that they will enable. We highlight three main surveys: a medium-deep continuum weak lensing and low-redshift spectroscopic HI galaxy survey over 5 000 deg2; a wide and deep continuum galaxy and HI intensity mapping (IM) survey over 20 000 deg2 from
$z = 0.35$
to 3; and a deep, high-redshift HI IM survey over 100 deg2 from
$z = 3$
to 6. Taken together, these surveys will achieve an array of important scientific goals: measuring the equation of state of dark energy out to
$z \sim 3$
with percent-level precision measurements of the cosmic expansion rate; constraining possible deviations from General Relativity on cosmological scales by measuring the growth rate of structure through multiple independent methods; mapping the structure of the Universe on the largest accessible scales, thus constraining fundamental properties such as isotropy, homogeneity, and non-Gaussianity; and measuring the HI density and bias out to
$z = 6$
. These surveys will also provide highly complementary clustering and weak lensing measurements that have independent systematic uncertainties to those of optical and near-infrared (NIR) surveys like Euclid, LSST, and WFIRST leading to a multitude of synergies that can improve constraints significantly beyond what optical or radio surveys can achieve on their own. This document, the 2018 Red Book, provides reference technical specifications, cosmological parameter forecasts, and an overview of relevant systematic effects for the three key surveys and will be regularly updated by the Cosmology Science Working Group in the run up to start of operations and the Key Science Programme of SKA1.
The aims of the research reported here were to identify potential risk factors associated with the presence of Staphylococcus aureus intramammary infection (IMI) in pre partum dairy heifers on 17 dairy farms from three provinces of Argentina and to characterize, at molecular level, isolates from those heifers and lactating cows from two selected herds. A total of 1474 heifers and 4878 lactating cows were studied. The prevalence of Staphylococcus aureus IMI in the heifers, heifers at quarter level and lactating cow mammary quarters was 14.41, 4.82, and 14.65%, respectively. Univariate analysis showed the key variables associated with S. aureus IMI presence in the heifers were: S. aureus IMI prevalence in cows of the lactating herd, the time calves stayed with their dam after birth, the calf rearing system, the place of rearing (own farm or other dairy farm) and fly control on the farm. None of the variables included in the multivariable analysis was associated with the presence of S. aureus IMI in the pre partum heifers, probably due to low variability among management practices used by the farms for rearing the heifer calves. At the molecular level, S. aureus isolates were grouped into three main PFGE clusters and several genotypes within the clusters. Isolates from mammary secretion of pre partum heifers and milk of lactating cows comprised different PFGE clusters in both herds, although two exceptions occurred. The absence of gene fnbpB, which codifies for a virulence factor protein involved in cell invasion by S. aureus, was significantly more frequent in pre partum heifer secretion isolates than in isolates from lactating cow milk. These results suggest that, under these management conditions, isolates from mammary secretions of pre partum heifers do not originate from the milk of lactating cows, but rather other sources to which the heifer is exposed.
Little is known about changes in brain functioning after first-episode psychosis (FEP). Such knowledge is important for predicting the course of disease and adapting interventions. Functional magnetic resonance imaging has become a promising tool for exploring brain function at the time of symptom onset and at follow-up.
A systematic review of longitudinal fMRI studies with FEP patients according to PRISMA guidelines. Resting-state and task-activated studies were considered together.
Eleven studies were included. These reported on a total of 236 FEP patients were evaluated by two fMRI scans and clinical assessments. Five studies found hypoactivation at baseline in prefrontal cortex areas, two studies found hypoactivation in the amygdala and hippocampus, and three others found hypoactivation in the basal ganglia. Other hypoactivated areas were the anterior cingulate cortex, thalamus and posterior cingulate cortex. Ten out of eleven studies reported (partial) normalization by increased activation after antipsychotic treatment. A minority of studies observed hyperactivation at baseline.
This review of longitudinal FEP samples studies reveals a pattern of predominantly hypoactivation in several brain areas at baseline that may normalize to a certain extent after treatment. The results should be interpreted with caution given the small number of studies and their methodological and clinical heterogeneity.
Loyalty cards programs have been used by retailers to increase customer retention. Loyality cards provide means to identify a particular customer and to collect customer-specific data, thus enabling individualized marketing; however, operating a loyalty program is complicated for retailers since they require to manage balances, collections, and transfers of customers. This is exactly the same problem the retailers were facing before credit cards were readily available. A new problem is that customers now have too many cards, customers may forget, or even deliberately decide to carry only a selection of their cards. This paper proposes a loyalty program based on a blockchain that does not require a physical card for identifying customers as it associates customers to their phone numbers, since nowadays people always carry their phone. In this perspective, companies can reduce overhead costs associated to managing the loyalty program. This paper reviews the technology required and describes the implementation of a loyalty program based on blockchains. Finally, it also enumerates the reasons for choosing the blockchain technology for this application.
In cases of mass-casualty incidents (MCIs), triage represents a fundamental tool for the management of and assistance to the wounded, which helps discriminate not only the priority of attention, but also the priority of referral to the most suitable center.
The objective of this study was to evaluate the capacity of different prehospital triage systems based on physiological parameters (Shock Index [SI], Glasgow-Age-Pressure Score [GAP], Revised Trauma Score [RTS], and National Early Warning Score 2 [NEWS2]) to predict early mortality (within 48 hours) from the index event for use in MCIs.
This was a longitudinal prospective observational multi-center study on patients who were attended by Advanced Life Support (ALS) units and transferred to the emergency department (ED) of their reference hospital. Collected were: demographic, physiological, and clinical variables; main diagnosis; and data on early mortality. The main outcome variable was mortality from any cause within 48 hours.
From April 1, 2018 through February 28, 2019, a total of 1,288 patients were included in this study. Of these, 262 (20.3%) participants required assistance for trauma and injuries by external agents. Early mortality within the first 48 hours due to any cause affected 69 patients (5.4%). The system with the best predictive capacity was the NEWS2 with an area under the curve (AUC) of 0.891 (95% CI, 0.84-0.94); a sensitivity of 79.7% (95% CI, 68.8-87.5); and a specificity of 84.5% (95% CI, 82.4-86.4) for a cut-off point of nine points, with a positive likelihood ratio of 5.14 (95% CI, 4.31-6.14) and a negative predictive value of 98.7% (95% CI, 97.8-99.2).
Prehospital scores of the NEWS2 are easy to obtain and represent a reliable test, which make it an ideal system to help in the initial assessment of high-risk patients, and to determine their level of triage effectively and efficiently. The Prehospital Emergency Medical System (PhEMS) should evaluate the inclusion of the NEWS2 as a triage system, which is especially useful for the second triage (evacuation priority).
The burrower bug Scaptocoris castanea Perty, 1830 (Hemiptera: Cydnidae) is an agricultural pest feeding on roots of several crops. The histology and ultrastructure of the salivary glands of S. castanea were described. The salivary system has a pair of principal salivary glands and a pair of accessory salivary glands. The principal salivary gland is bilobed with anterior and posterior lobes joined by a hilus where an excretory duct occurs. The accessory salivary gland is tubular with a narrow lumen that opens into the hilus near the excretory duct, suggesting that its secretion is stored in the lumen of the principal gland. The cytoplasm of the secretory cells is rich in the rough endoplasmic reticulum, secretory vesicles with different electron densities and mitochondria. At the base of the accessory gland epithelium, there were scattered cells that do not reach the gland lumen, with the cytoplasm rich in the rough endoplasmic reticulum, indicating a role in protein production. Data show that principal and accessory salivary glands of S. castanea produce proteinaceous saliva. This is the first morphological description of the S. castanea salivary system that is similar to other Hemiptera Pentatomomorpha, but with occurrence of basal cells in the accessory salivary gland.
A simple and facile stereolithography 3D printing technique was utilized to fabricate piezoelectric photopolymer-based polyvinylidene fluoride (PVDF) blends. Different process variables, such as solvent (N,N-dimethylformamide, DMF) to PVDF ratio and PVDF solution to photopolymer resin (PR) ratio, were engineered to enhance the dispersion of the PVDF into the PR so as to achieve the maximum piezoelectric coupling coefficient. Our results demonstrate that a ratio of 1:10 (PVDF:DMF) and 2 wt%-PVDF/PR was optimal for the best dissolution of the PVDF, 3D printability, and piezoelectric properties. Under these conditions, the blend generated ±0.121 nA under 80 N dynamic loading excitation. We believe that the findings of this work would promote many further studies on the mass production of flexible piezoelectric polymer blends with higher quality finished surface and design flexibility.
Cancer during pregnancy has an incidence of 1/1,000, and when diagnosed, the most common ones are breast cancer (1/10,000), Hodgkin’s lymphoma (1/6,000), and head and neck cancer (1/10,000). If a diagnosis is made during pregnancy, the treatment cannot wait until delivery, and there is concern about the effects that radiotherapy may have on the foetus. The multidisciplinary group has to assess and ethically make decisions with regard to the mother and foetus.
A 35-year-old female, a carrier of Behcet’s disease, underwent 5 years of treatment with hydroxychloroquine, prednisone and low-molecular-weight heparin (the patient being a carrier of Behcet’s disease, there is a high risk for cancer of the oral cavity and oropharynx with an HR of 2·11, so the cancer could be related to the tonsil). The patient’s oncological situation started on December 2017 with a volume increase in preauricular, parotid and right mandibular angle, with a progressive growth. At this time, the foetus was of 17·5 weeks of gestation. An oral cavity tumour that invaded the right retromolar triangle was observed, and upon biopsy, a basaloid squamous cell carcinoma was diagnosed.
Radiotherapy treatment was started at 22 weeks of gestation; intensity-modulated radiation therapy (IMRT) was planned with a dose of 69·96 Gy to the primary tumour and 59·4 Gy to ganglion levels II, III and IV, bilaterally in 33 fractions. At fraction 27 a significant decrease in tumour volume was noted, so adaptive radiotherapy was performed to complete the treatment. Currently the patient has no clinical evidence of tumour pathology.
The risk of radiation exposure in pregnant women (after 20 weeks of gestation), being treated for cancers of the tonsil, reaching the foetus is minimal, with a reduced risk of a few or no effects.
Radiotherapy in tonsil cancer has been shown to be effective in combination with chemotherapy for local control of the disease. In the case of this pregnant patient, radiotherapy, as the only modality, provided local control and little exposure of radiation to the foetus.
This research communication addresses the hypothesis that the association of dietary vitamin E and Yerba Mate could help to prevent or decrease oxidation of milk enriched in unsaturated fatty acids (UFA). Four multiparous lactating Holstein cows were used in a 4 × 4 Latin square. Treatments were: (1) control diet with no Yerba Mate or vitamin E; (2) diet containing 375 IU/kg vitamin E; (3) diet containing 30 g/kg Yerba Mate; and (4) diet containing 375 IU/kg vitamin E and 30 g/kg Yerba Mate. To increase unsaturated fatty acids in milk, cows were fed 172 g/kg soybean seeds (on a dry matter basis). There was no interaction between vitamin E and Yerba Mate supplementation for milk antioxidant-related (polyphenols, reducing power, conjugated dienes, and TBARS) analyses. Milk reducing power was increased when cows were supplemented with Yerba Mate. Our results suggest that the association of dietary vitamin E and Yerba Mate does not help to prevent or decrease oxidation of milk in UFA.
The first period of agrarian reforms with clear state control over the land (African socialisms) took place between 1945 and 1980, but then a second period started in which market agrarian reforms have prevailed. This work synthesizes agrarian structural reform policies (property systems and land tenure) between 1980 and 2016 in African countries, especially those that had or have bureaucratic bourgeoisie governments (one-party and/or African socialist). The two periods are complementary, rather then being opposed to each other, as state agrarian reforms smoothed the path to market agrarian reforms. Although there is not yet sufficient empirical research on the results of the agrarian reforms implemented during this period, our hypothesis is that they are helping to: increase the unequal structure of property; develop tenure systems and non-capitalist contractual labour relations in new ways, both non-associative (the grabbing of vast tracts of land) and associative (renewed control of customary lands by traditional authorities); and force peasant expropriation and the subsequent increase in the number of landless non-proletarianized peasants. Therefore, the problem of poor agrarian structures in Africa is still unresolved.
The regulatory framework of the red octopus (Octopus maya) fishery includes total allowable catches (TAC), which are based on studies conducted on the population that occurs in shallow waters. In fact, most of the biological studies of this species refer to the fraction of the population that occupies waters less than 30 m deep; however, O. maya can occur up to a 60 m depth. The aim of this study is to assess the stock of O. maya that occupies waters between 30 m and 60 m deep. Four research cruises were carried out during the closed and fishing seasons, from May 2016 to January 2017. An average of 29 sampling sites were surveyed in each cruise (±2 sampling sites) using a commercial vessel with a uniform sampling effort. In each sampling site, the swept area, the total number of octopuses captured, the total weight of the catch, and the individual weight of octopuses were recorded. Biomass was obtained with four methods: stratified random method, swept area method, geostatistical biomass model, and an unpublished method of weighted swept area. The four methods provided consistent results. The distribution pattern of species was in patches, although before the fishing season started it was more homogeneous. The fraction of the population that occurs between 30 m and 60 m deep consisted mostly of adult organisms, so it could be contributing significantly to the recruitment of the entire population, even to the fraction that is exploited.
Emergency physicians play a frontline role in hospital disaster responses and require appropriate training.
The aim of the current study was to pilot and compare the effectiveness of two emergency preparedness teaching interventions: the first employing traditional lecture-based instruction (LEC) and the second utilizing interactive simulation/game-based teaching (SIM).
A two-group randomized pre- and post-test design was implemented into the didactic curriculum of the Emergency Medicine (EM) Residency Training Program at the San Lucas Episcopal Hospital in Ponce, Puerto Rico. Residents (n=23) completed either a LEC (control) or SIM teaching module (single day, one to two hours) focusing on emergency preparedness concepts, disaster-related clinical decision-making, and physician responsibilities during hospital disaster protocols. Knowledge-based multiple-choice exams and scenario-based competency exams were administered at three different time points: one-week pre-intervention, immediately post-training, and two-weeks post-training. Test scores were compared between groups at each time point using the Mann-Whitney U test.
Following the teaching interventions, no significant differences were found between the LEC group versus the SIM group in knowledge-based exam performance (LEC 81.1%[9.4] vs. SIM 74.9%[12.1]; U=42.50, p=0.15) and scenario-based exam performance (LEC 80.0%[9.7] vs. SIM 80.2%[9.2]; U=62.00, p=0.83), suggesting both teaching methods were similarly effective. Indeed, knowledge-based exam scores improved two-fold and scenario-based exam scores improved by over 50% immediately following training relative to baseline exam scores. Two-weeks post-training, a significant decrease in scenario-based exam performance was found in the LEC group relative to the SIM group (LEC 63.1%[11.6] vs. SIM 75.4%[11.5]; U=91.50, p=0.036), suggesting residents who train with simulations show greater retention of scenario-based concepts compared to those who train with lecture-based training alone.
The current study highlights the potential dual value of incorporating simulation training in EM emergency preparedness curriculums in improving both knowledge and concept retention of physician disaster responsibilities.
Boring sponges are an important component of bioeroder assemblages in tropical coral reefs. They are considered as a potential threat for coral reef health, and the increase of dead corals is expected to promote their abundance. The relationship between the availability of dead coral substrata and the development of boring sponge assemblages was evaluated during El Niño 2015–16 at five reefs from Zihuatanejo, Guerrero, Mexico. Environment and substrate quality were assessed. Overall, environment conditions remained normal in relation to previous studies in the area. Only water temperature showed unusually high records at all sites and coincided with bleaching and mortality of corals, possibly caused by the effects of the El Niño event. Abundance of boring sponges in dead corals and coral rubble was lower than during previous studies. Although sponge abundance was not directly related to cover of both dead corals and coral rubble, cover of dead corals showed a high correlation with the variation in the structure of sponge assemblages across sites. Cliona vermifera dominated sponge assemblages at all sites, and its abundance was high under conditions of high cover of live corals and low cover of bleached corals. Since overall sponge abundance responded in a similar way, these results suggest that boring sponge assemblages dominated by C. vermifera are enhanced by conditions favourable for corals. Our results imply that El Niño events in the Mexican Pacific are not likely to cause immediate population outbreaks of boring sponges.
Bankruptcy is a precise legal process defining, ex ante, the rules for allocation of assets when debtors fail to repay their legally constituted debts. Ultimately, these rules determine willingness to lend and to borrow, and thus economic growth. In 1706, Parliament in England passed a bankruptcy statute that allowed, for the first time, bankrupts to exit the state of bankruptcy prior to full repayment of all debts. This represented a fundamental change in English bankruptcy rules: creditors could now choose to discharge a bankrupt. Obviously, bankrupts benefitted from such a discharge, but creditors could also benefit from greater asset revelation. We document that discharge was quickly adopted, and estimate that many bankrupts received a second chance in business.
Human–bear conflicts resulting from livestock depredation and crop use are a common threat to the brown bear Ursus arctos throughout its range. Understanding these conflicts requires the recording and categorization of incidents, assessment of their geographical distribution and frequency, and documentation of the financial costs and the presence of any preventative measures. Damage compensation schemes can help mitigate conflicts and, in some cases, improve acceptance of bears. This study aims to elucidate the major factors determining the patterns of damage caused by bears, examine the effectiveness of preventative measures in reducing such damage, and identify bear damage hotspots in Croatia. Our analysis is based on damage reports provided by hunting organizations to the Croatian Ministry of Agriculture during 2004–2014. The highest number of claims were made for damage to field crops and orchards. Damage to livestock, agricultural crops and beehives resulted in the highest total cost to farmers. Damage to beehives and to automatic corn feeders for game species incurred the highest cost per damage event. We identified a hotspot for bear damage claims in Croatia, located near Risnjak National Park and the border with Slovenia. Damage appears higher in areas that have more villages closer to protected areas and a greater per cent of forest cover, indicating a synergistic effect of protected environments that facilitate bear movements and the presence of human activities that provide easily accessible food for bears.
As apex predators, sharks are known to play an important role in marine food webs. Detailed information on their diet and trophic level is however needed to make clear inferences about their role in the ecosystem. A total of 335 stomachs of smooth hammerhead sharks, Sphyrna zygaena, were obtained from commercial fishing vessels operating in the Ecuadorian Pacific between January and December 2004. A total of 53 prey items were found in the stomachs. According to the Index of Relative Importance (%IRI), cephalopods were the main prey (Dosidicus gigas, Sthenoteuthis oualaniensis, Ancistrocheirus lesueurii and Lolliguncula [Loliolopsis] diomedeae). Sphyrna zygaena was thus confirmed to be a teutophagous species. The estimated trophic level of S. zygaena was between 4.6 and 5.1 (mean ± SD: 4.7 ± 0.16; males: 4.7; females: 4.8). Levin's index (BA) was low (overall: 0.07; males: 0.08; females: 0.09), indicating a narrow trophic niche. We found that sharks <150 cm in total length consumed prey of coastal origin, whereas sharks ≥150 cm foraged in oceanic waters and near the continental shelf. The analyses indicate that S. zygaena is a specialized predator consuming mainly squids.