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In this work using computer simulations of 3D model of dense disordered solids we show, for the first time, the appearance of shear localization in the stationary flow under homogeneous driving conditions. To rationalize our simulation results we develop a continuum model, that couples the dynamics of the local flow to the evolution of a kinetic temperature field related to the local inertial dynamics. Our model predicts that the coupling of the flow field to this additional destabilizing field appears only as a necessary condition for shear localization, a minimum system size is necessary to accommodate the flow instability. Moreover we show that this size criterion resulting from our continuum description is in quantitative agreement with our particle-based simulation results., (© 2023. The Author(s), under exclusive licence to EDP Sciences, SIF and Springer-Verlag GmbH Germany, part of Springer Nature.)

Porcine respiratory complex syndrome has a strong economic impact on the swine breeding sector, as well as a clear repercussion on the wellbeing of the animals, leading to overuse of antimicrobial molecules. Algal extracts used in short-term treatments are empirically recognized by farmers as having a positive effect on pigs' health, however, their mechanisms of action are not well known and more research is needed. Herein we studied the short and median term impact of three algal extracts, in vitro, on the pro-inflammatory and antiviral responses of porcine primary blood monocytes and alveolar macrophages, as well as the susceptibility of the treated cells to infection by Porcine Respiratory and Reproductive Syndrome Virus (PRRSV) and the Aujeszky's Disease Virus (ADV). All extracts presented a pro-inflammatory short-term effect, associated for two of them, with an inhibition of the PRRSV replication. Conversely, the three extracts presented an anti-inflammatory median term effect, with no impact on PRRSV replication. The observed immune modulation prompts us to test, in vivo, the anti-PRRSV action of algal extracts and strengthen the interest for this natural resource.

To assess the evolution in prevalence, awareness and control of hypertension for over 10 years in Pernambuco State, Northeast Brazil, two cross-sectional studies were conducted based on random samples of households in urban and rural areas, in 2006 and 2015/2016, involving adults aged 20 years or older. Hypertension was defined as systolic blood pressure of at least 140mmHg or diastolic blood pressure of at least 90mmHg as well as the reported use of antihypertensive medication. A logistic regression analysis was conducted to estimate the influence of the social, behavioral and anthropometric determinants on hypertension. Although social and behavioral factors improved in this 10-year period, overweight and abdominal obesity increased. Approximately one third of the adult population of Pernambuco had hypertension in 2006 and this prevalence was maintained in 2015/2016. In rural areas, awareness concerning hypertension rose from 44.8% in 2006 to 67.3% in 2015/2016, and control from 5.3% to 27.1%, so that awareness and control were similar in urban and rural areas in 2015/2016. After an adjustment for potential confounding factors, the likelihood of having hypertension more than doubled among men (OR = 2.03; p < 0.001), middle (OR = 4.41; p < 0.001) and old-age subjects (OR = 14.44; p < 0.001), and those who had abdominal obesity (OR = 2.04; p < 0.001) in urban areas and among middle-aged (OR = 2.56; p < 0.001), less educated individuals (OR = 2.21; p = 0.006) and those who were overweight (OR = 2.23; p < 0.001) in rural areas. Despite the favorable evolution in the management of hypertension in Pernambuco, public health measures focused in vulnerable populations are still required, mainly in rural areas, to improve primary prevention and decrease the disease rate.

Marine microalgae are known to be a source of bioactive molecules of interest to human health, such as n-3 polyunsaturated fatty acids (n-3 PUFAs) and carotenoids. The fact that some of these natural compounds are known to exhibit anti-inflammatory, antioxidant, anti-proliferative, and apoptosis-inducing effects, demonstrates their potential use in preventing cancers and cardiovascular diseases (CVDs). Benzo[a]pyrene (B[a]P), a polycyclic aromatic hydrocarbon (PAH), is an ubiquitous environmental pollutant known to contribute to the development or aggravation of human diseases, such as cancer, CVDs, and immune dysfunction. Most of these deleterious effects are related to the activation of the polycyclic aromatic hydrocarbon receptor (AhR). In this context, two ethanolic microalgal extracts with concentrations of 0.1 to 5 µg/mL are tested, Ostreoccoccus tauri (OT) and Phaeodactylum tricornutum (PT), in order to evaluate and compare their potential effects towards B[a]P-induced toxicity in endothelial HMEC-1 cells. Our results indicate that the OT extract can influence the toxicity of B[a]P. Indeed, apoptosis and the production of extracellular vesicles were decreased, likely through the reduction of the expression of CYP1A1, a B[a]P bioactivation enzyme. Furthermore, the B[a]P-induced expression of the inflammatory cytokines IL-8 and IL1-β was reduced. The PT extract only inhibited the expression of the B[a]P-induced cytokine IL-8 expression. The OT extract therefore seems to be a good candidate for counteracting the B[a]P toxicity., Competing Interests: The authors declare no conflict of interest.

Several studies in Hawaii have focused on arthropod succession and decomposition patterns of surface remains, but the current research presents the first study to focus on shallow burials in this context. Three domestic pig carcasses (Sus scrofa L.) were buried at the depths of 20-40 cm in silty clay loam soil on an exposed ridge on the leeward side of the volcanically formed Koolau Mountain Range. One carcass was exhumed after 3 weeks, another after 6 weeks, and the last carcass was exhumed after 9 weeks. An inventory of arthropod taxa present on the carrion and in the surrounding soil and observations pertaining to decomposition were recorded at each exhumation. The longer the carrion was buried, the greater the diversity of arthropod species that were recovered from the remains. Biomass loss was calculated to be 49% at the 3-week interval, 56% at the 6-week interval, and 59% at the 9-week interval., (© 2014 American Academy of Forensic Sciences.)

Purpose: To assess the correlation between macular pigment optical density and plasma levels of lutein, zeaxanthin, and fatty acids, especially omega-3 polyunsaturated fatty acids (PUFAs)., Methods: The PIMAVOSA study is an observational study of 107 healthy volunteers, aged 20 to 60 years and born in southwest France, without histories of ocular disease. Macular pigment optical density (MPOD) was measured using the two-wavelength autofluorescence method with a modified scanning laser ophthalmoscope. Plasma measurements (lutein, zeaxanthin, and fatty acids) were performed from fasting blood samples collected on the day of the eye examination., Results: MPOD within 6° correlated with plasma levels of lutein and zeaxanthin (r = 0.35, P < 0.001, and r = 0.30, P < 0.005, respectively). MPOD also significantly correlated with total plasma omega-3 PUFAs (r = 0.22, P < 0.05). Among the different omega-3 PUFAs, docosapentaenoic acid (DPA) had the highest correlation with MPOD (r = 0.31, P < 0.001), whereas correlation with eicosapentaenoic acid (EPA) was moderate (r = 0.21, P < 0.05) and did not reach statistical significance for docosahexaenoic acid (r = 0.14, P = 0.14)., Conclusions: In the present study, macular pigment density was associated not only with plasma lutein and zeaxanthin but also with omega-3 long-chain PUFAs, particularly with EPA and DPA. Further studies will be needed to confirm these findings and to identify the underlying mechanisms.

More than half of the Hawaiian honeycreepers (Drepanidinae) known from historical records are now extinct. Introduced mosquito-borne disease, in particular the avian malaria Plasmodium relictum , has been incriminated as a leading cause of extinction during the 20th century and a major limiting factor in the recovery of remaining species populations. Today, most native Hawaiian bird species reach their highest densities and diversity in high elevation (>1,800 m above sea level) forests. We determined the thermal requirements for sporogonic development of P. relictum in the natural vector, Culex quinquefasciatus , and assessed the current distribution of native bird species in light of this information. Sporogonic development was completed at constant laboratory and mean field temperatures between 30 and 17 C, but development, prevalence, and intensity decreased significantly below 21 C. Using a degree-day (DD) model, we estimated a minimum threshold temperature of 12.97 C and a thermal requirement of 86.2 DD as necessary to complete development. Predicted (adiabatic lapse-rate) and observed summer threshold isotherm (13 C) correspond to the elevation of high forest refuges on the islands of Maui and Hawai'i. Our data support the hypothesis that avian malaria currently restricts the altitudinal distribution of Hawaiian honeycreeper populations and provide an ecological explanation for the absence of disease at high elevation.

The relationship between the human body and the dissemination of potentially pathogenic particles and droplets is described. Airborne transmission of infection in operating theatres and a burns unit and the part played by the human microclimate and its interaction with ventilating air flows is discussed. The mechanisms by which different garment assemblies used for surgery can enhance particle dispersion are illustrated and the way that floor cleaning can increase the concentration of airborne organisms is described. The development of the successful use of ultra-clean air systems in orthopaedic implant surgery is reviewed. Relationships between contact and airborne transmission of disease are explored and ways by which containment strategies and metrics used in pharmaceutical and electronics manufacturing can be applied to the design and monitoring of healthcare areas is discussed. It is suggested that currently available techniques involving architectural, ventilation and operational aspects of healthcare provision, when properly applied, can markedly improve treatment outcomes that may otherwise be compromised by hospital-acquired infections involving both bacteria and viruses.

To identify potential vectors of avian malaria in Hawaiian native forests, the innate susceptibility of Aedes albopictus, Wyeomyia mitchellii, and Culex quinquefasciatus from 3 geographical sites along an altitudinal gradient was evaluated using local isolates of Plasmodium relictum. Mosquitoes were dissected 5-8 and 9-13 days postinfective blood meal and microscopically examined for oocysts and salivary-gland sporozoites. Sporogony was completed in all 3 species, but prevalence between species varied significantly. Oocysts were detected in 1-2% and sporozoites in 1-7% of Aedes albopictus that fed on infected ducklings. Wyeomyia mitchellii was slightly more susceptible, with 7-19% and 7% infected with oocysts and sporozoites, respectively. In both species, the median oocyst number was 5 or below. This is only the second Wyeomyia species reported to support development of a malarial parasite. Conversely, Culex quinquefasciatus from all 3 sites proved very susceptible. Prevalence of oocysts and sporozoites consistently exceeded 70%, regardless of gametocytemia or origin of the P. relictum isolate. In trials for which a maximum 200 oocysts were recorded, the median number of oocysts ranged from 144 to 200. It was concluded that Culex quinquefasciatus is the primary vector of avian malaria in Hawai'i.

The isolation, amplification, and characterization of human DNA from hematophagous (blood feeding) and necrophagous (carrion feeding) arthropods have been advanced significantly by the development of polymerase chain reaction (PCR) DNA sequencing methodologies. Historically, DNA technology has been successfully utilized to identify individual hosts upon which species of hematophagous arthropods have fed. The analysis of hematophagous insects' gut content blood meals has led to major advances in medical entomology and vector-borne disease epidemiology. In the forensic arena, the ability to apply similar techniques to insects recovered from badly decomposed remains has been greatly enhanced through the advent of mitochondrial DNA (mtDNA) techniques. Mitochondrial DNA analyses have been utilized to identify both the human remains upon which fly larvae (maggots) have fed and the species of the larvae themselves. The preliminary work detailed here demonstrates, for the first time, the successful application of mtDNA sequencing techniques to the analysis of necrophagous beetle larvae. A small sample of sap beetle larvae, Omosita spp. (Coleoptera: Nitidulidae), was collected from human skeletal remains during anthropological examination and analyzed for human DNA using mtDNA sequencing. The beetle larvae yielded mtDNA matching that of the host human bone. The results detailed here further demonstrate the robust nature of human mtDNA and the ability to recover valuable mtDNA evidence from forensically important, late decompositional stage insect species.

peruensis is described as new from specimens collected from Oryzomys yunganus, Proechimys quadruplicatus, and Oryzomys megacephalus taken in Peru. A new character of a nude tactile seta on femur III is noted for the genus and a key to the species of Polylopadium is presented.

To study the potential use of insects remains as toxicological indicators, we measured morphine in desiccated entomological materials using a radioimmunoassay method (Coat-A-Count Serum Morphine, Dade Behring, France) following enzymatic hydrolysis.First, enzymatic cuticle extraction of morphine (pronase digestion preceded by a 2h incubation with a dithiothreitol solution) was performed on various substrates (Calliphoridae puparial cases and desiccated adults, and desiccated pupae of Dermestidae) which were then tested to identify possible interferences with the radioimmunoassay procedure. This same procedure was performed on puparial cases and desiccated adults of Lucilia sericata (Diptera, Calliphoridae) previously reared on minced meat containing various morphine concentrations. Morphine was detected only in cuticle powder from insects reared on meats containing 100 and 1000mg/kg. Higher concentrations were measured in puparial cases. Rearings on psoas from eight heroin overdose victims confirmed previous experimental results. Remains of necrophagous insects, particularly puparial cases, are often preserved for a long time, and consequently can serve as late alternative specimens for toxicological analysis when suitable tissues are not available.

Entomotoxicology is a relatively new branch of forensic entomology. The potential use of insects for detecting drugs and other toxins in decomposing tissues has been widely demonstrated. In death investigations, Diptera and other arthropods can be reliable alternate specimens for toxicological analyses in the absence of tissues and fluids normally taken for such purposes. Entomotoxicology also investigates the effects caused by drugs and toxins on arthropod development in order to assist the forensic postmortem interval estimates. However, several remarks on the limitations of entomotoxicology have been highlighted recently. In this paper, the implications for the practice of this forensic procedure are fully reviewed.

Morphine was detected by immunohistochemistry on sections of third stage larvae of Calliphora vomitoria (Diptera, Calliphoridae) reared on minced beef meat previously treated with morphine hydrochloride. The detection was performed with an avidin-biotin-peroxidase-complex method. Positive specimens showed specific staining of the haemolymph and a more intense immunoreaction in an area located at the limit between exocuticle and endocuticle. These results constitute an evidence of morphine accumulation inside the cuticle of Diptera larvae during their development. During the pupariation, the larval cuticle is transformed into the sclerotized puparium. This study consequently points out the possibilities of analyzing empty pupariae when suitable tissues or living necrophagous insects are absent.

Two species of necrophagous Coleoptera: Dermestes frischi (Dermestidae) and Thanatophilus sinuatus (Silphidae), were reared on substrates containing different amounts of morphine. Colonies of D. frischi were reared on rabbit carcasses which had been given 10, 20, and 40 mg/h of morphine hydrochloride via ear artery perfusion over a 3 h period prior to death. A fourth rabbit served as a control. T. sinuatus was reared on minced beef spiked with morphine hydrochloride to give concentrations of 1,000, 2,500, 5,000, and 10,000 ng/g and one control colony. These dosages were calculated to create tissue concentrations of morphine similar to those encountered in human deaths due to morphine overdose. Larvae. pupae, and adults (except for T. sinuatus) were analyzed for morphine content. All developmental stages of D. frischi were positive for morphine and concentrations correlated with cadaveric tissue concentrations during larval stages and to a lesser extent in the adult stage. For T. sinuatus, the best correlations were found in 2nd and 3rd instar larvae. This study demonstrates the potential for use of necrophagous Coleoptera, as well as Diptera larvae, as alternate specimens for toxicological analyses.

Studies were conducted to determine development rates of of Dermestes maculatus DeGeer at temperatures of 15, 20, 25, 30, and 35 degrees C. No individuals completed development to the adult stage at 15 degrees C. For the other temperatures, survivorship ranged from 9.3% at 20 degrees C to 36% at 35 degrees C. Time required for development varied inversely with temperature from a mean of 89.7 d at 20 degrees C to 36.4 d at 35 degrees C. For specimens held individually, survivorship was higher at 25 and 30 degrees C, i.e., 83.2 and 60.2%, respectively. No specimens held individually at 35 degrees C survived past the first larval instar. Mortality during the egg stage at 25 and 30 degrees C was 4.52-5.23%, whereas mortality during the first instar was significantly higher for the individuals held at 30 degrees C and 100% for those at 35 degrees C. There was an inverse relation observed between larval density and both survivorship and mean adult weights.

Mange caused by the epidermoptid mite Myialges nudus (Acari: Epidermoptidae) is described in 31 dead fledgling Laysan albatrosses (Phoebastria immutabilis) from Midway Atoll (Hawaii, USA) sampled from 18 June to 10 July 1990 and from 21 June to 22 July 1991. This is the first record for this parasite from this host. Mites were collected from the skin; were located primarily in the stratum corneum; and were associated with mild to severe granulomatous inflammation, hyperkeratosis, dermal edema, ballooning degeneration of keratinocytes, neovascularization, and subdermal fibrosis. The severity of inflammation in some birds suggested that dermatitis due to M. nudus could be a significant cause of morbidity, or even mortality, in these birds.

The performance of a fume cupboard is determined by a complex interaction of factors which are time consuming and expensive to determine. This paper describes a simple and practical means of ranking, and assessing fume cupboard installations that can help to discharge managerial responsibility for a 'safe' environment. The method also gives an economically viable and technically defensible system for assessing fume cupboard performance as part of upgrading exercises or performance audits. The assessment strategy uses flow visualisation techniques and measurements of inflow air velocity as well as overall condition evaluation to rank performance and identify poor performing cupboards. The method has been used to carry out a condition and performance survey of 199 fume cupboards, both aerodynamic and box-type designs, in an academic institution. The results of this survey are presented which not only highlight performance characteristics but also provide insights into user attitudes and knowledge of fume cupboard operation and performance. It is suggested that surveys such as this could be helpful in training programmes for laboratory workers to enable them to optimise the use of fume cupboards.

A commercially available computational fluid dynamic (CFD) software program, specific for HVAC systems, was used to study the performance of an aerodynamic fume cupboard. The numerical results showed good qualitative agreement with physical measurements giving confidence in the CFD model to simulate and predict overall fume cupboard performance. However, there were some quantitative differences specifically around 'aerodynamic' features that could not be accurately simulated by the software code. The CFD model was clearly able to demonstrate differences in performance between good and bad cupboard designs, and show the importance of using rear baffles and lipfoils. It also showed the importance of good design features when a 'worker' was standing against the front edge or when there were draughts in front of the aperture. The computer model was used to simulate the gas tracer containment test method described in BS 7258 (1994) [Laboratory Fume Cupboards], and had a much greater sensitivity than the recommended physical measuring instruments. The results given in this paper demonstrate the potential for using a commercially available software package for the optimisation of fume cupboard design and testing. It also indicates the economy of using CFD compared with building a prototype and testing a model.

The formation of pressure ulcers can be exacerbated by a breakdown in the integrity of the patient's skin caused by poor maintenance of the skin microclimate. Patient support systems (PSSs-specialised beds, mattresses, chairs, cushions and pads) play an important role in the dissipation of heat and moisture away from the skin/support interface which is necessary in order to maintain the physiological skin microclimate. This paper reports a laboratory method and theory for the simultaneous measurement of the heat and water vapour dissipating properties of PSSs. The results demonstrate that the method is extremely selective, exhibiting very significant differences between the PSSs tested. It also shows that assessing PSS covers independently does not necessarily indicate the overall performance of the complete PSS.

Odontacarus khanjani Goff & Saboori (Leeuwenhoekiidae) and Neotrombicula iranensis Goff & Saboori (Trombiculidae) were described as new. Both species were collected as unengorged larvae on alfalfa plants, Medicago sativa, in western Iran.

Decomposition studies were conducted using carcasses of domestic pigs, Sus scrofa L., one burned and the other unburned (the control) to determine effects of burning on arthropod succession patterns. The burnt carcass corresponded to a CGS level #2 burn victim. The studies were conducted in two contrasting habitats, both on the island of Oahu. The first was conducted in a xerophytic habitat from 1 Sept. 1995 through 1 Oct. 1995 while the second was conducted in a rainforest habitat from 29 April 1996 to 28 May 1996. No marked differences were noted in arthropod fauna present or the duration of the stages of decomposition between the carcasses at either site. The major oviposition by flies of the family Calliphoridae occurred one day earlier on the burnt carcass than the control carcass at Diamond Head and four days earlier at Lyon Arboretum. This resulted in all successional waves onto the burnt carcass occurring one day earlier at Diamond Head and four days earlier at Lyon Arboretum. These differences could alter a postmortem interval estimate based on arthropod succession patterns by up to 24 hours and 4 days, respectively.