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Low impact development (LID) are prominent type of vegetated stormwater infrastructure that provides various ecosystem services, such as biodiversity, carbon storage, and improvement in air quality. This study investigated six LID technologies to assess SOC retention and factors influencing accumulation. Soil samples (0-20 cm depth) were analyzed using the Walkley-Black method, specifically focusing on wet oxidation. SOC stocks ranged from 18.5 to 66.3 t C/ha in the inflow and 18.6 to 79.1 t C/ha in the outflow, with SCW and TBF showing higher SOC due to root turnover, stormwater runoff, and media composition. This study found that vegetation and impervious catchments significantly influenced SOC levels. Trees exhibited higher SOC due to their extensive root systems and longer life cycles. Roads and parking lots had higher SOC from plant debris and hydrocarbons in stormwater runoff. SOC also varied seasonally, peaking in spring due to photosynthesis and decreasing in summer and autumn from increased microbial respiration. A complex relationship between SOC and soil physico-chemeical perameters were also investigated, with moisture content and total nitrogen being critical factors for carbon stocks. Overall, the results from this study are seen as beneficial in optimizing the design guidelines for LID technologies for carbon sequestration and green space expansion in urban areas., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Wear on the surface of the femoral head increases the risk of hip and femur fractures. Biomechanical experiments conducted on the femur are based on its bending and torsional rigidities. Studies regarding the deflection of the femur bone when the femoral head is coated with microfilms composed of durable and compatible biomaterials are poor. This study aimed to investigate the effects of different biomaterial microfilm coatings over the femoral head on the deflection of the human femur. We utilized 2023 R1 finite element analysis (FEA) software to model the directional deformation on the femoral head and examine the femur's deflection with varying microfilm thicknesses. The deflection of the femur bone was reported when the femoral head was uncoated and coated with titanium, stainless steel, and pure gold microfilms of different thicknesses (namely, 50, 75, and 100 μm). Our results show that the femur's minimum and maximum deflection occurred for stainless steel and gold, respectively. The deformation of the femur was lower when the femoral head was coated with a 50-micrometer microfilm of stainless steel, compared to the deformation obtained with gold and titanium. When the thickness of the microfilm for each of the materials was increased, the deformation continued to decrease. The minimum deformation of the femur occurred for a thickness of 100 μm with stainless steel, followed by titanium and gold. The difference in the directional deformation of the femur between the materials was more significant when the coating was 100 μm, compared to the thicknesses of 50 and 75 μm. The findings of this study are expected to significantly contribute to the development of advanced medical techniques to enhance the quality of life for patients with femur bone-related issues. This information can be used to develop more resilient coatings that can withstand wear and tear.

Introduction: HIV infection has become a chronic disease with a good long-term prognosis, necessitating a change in the care model. For this study, we applied a proposal for an Optimal Care Model (OCM) for people with HIV (PHIV), which includes tools for assessing patient complexity and their classification into profiles to optimize care provision., Methods: Observational, cross-sectional, and retrospective study. Adult PHIV treated at the Tropical Medicine consultations at Ramón y Cajal Hospital from January 1 to June 30, 2023, were included. The complexity calculation and the stratification into profiles for each patient were done according to the OCM., Results: Ninety-four participants were included, 76.6% cisgender men, with a median age of 41 years (range 23-76). Latin America and Africa were the main regions of origin (72.4%). 98% had an undetectable HIV viral load. The degree of complexity was 78.7% low, 11.7% medium, 1% high, and 8.5% extreme. The predominant profile was blue (64.9%), followed by lilac (11.7%), purple (6.3%), and green (4.3%). 7.4% were unclassifiable, of whom 57.2% had high/extreme complexity. Among the unclassifiable, mental health problems were the most common., Conclusions: The OCM tools for People Living with HIV (PLWH) allow for the classification and stratification of most patients in a consultation with a non-standard population. Patients who did not fit into the pre-established profiles presented high complexity. Creating a profile focused on mental health or mixed profiles could facilitate the classification of more patients., (Copyright © 2024 Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. Published by Elsevier España, S.L.U. All rights reserved.)

Lymphoid interstitial pneumonia (LIP) is a rare form of interstitial pulmonary disease, which has been described in association with a wide range of autoimmune disorders. Although the association of this entity with Sjogren's syndrome is well known, only a few cases are reported in relation to systemic lupus erythematosus (SLE). The aim of this paper is to review the cases reported in literature to date, as well as to describe the characteristics of these patients including the new case presented herein. We will be focusing on the case of a 36-year-old female patient diagnosed with SLE on hydroxychloroquine treatment who develops pleuritic chest pain and progressive dyspnea after 3 years of follow-up. The chest CT scan showed pleural thickening and both multiple and bilateral micronodules. A lung biopsy was also performed, revealing an infiltration of lymphocytes, plasma cells, and histiocytes in the alveolar septa suggestive of LIP. After conducting a review of the literature, we identified seven other cases describing SLE in association with LIP. The majority of them were young women, and LIP tends to appear early in the course of the disease, even as a form of initial presentation in some cases. Symptoms included cough, dyspnea, and pleuritic pain, with the exception of one case which was asymptomatic. It is noteworthy that half of the patients were positive for anti-SSA/anti-SSB autoantibodies, and some of them also met criteria for Sjogren's syndrome. Treatment with steroids and other immunosuppressive agents improved symptoms in all of them., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The objective of this study is to use DNA barcoding to link cystacanths and adults belonging to the acanthocephalans Corynosoma australe found in the Southeastern Pacific Ocean off the coast central from Peru. We sampled three species of commercial fish (Paralichthys adspersus (Steindachner), Paralabrax humeralis (Valenciennes), and Cheilodactylus variegatus (Valenciennes)) and two South American sea lions, Otaria byronia, stranded on the beaches of the city of Huacho and Barranca, Lima province. A total of 509 acanthocephalan larvae were found in the body cavity of 95 fish (prevalence 54.28%, total mean intensity 8.64). A total of 127 adult worms were found in the large intestine from two South American sea lions (P= 100%, MI= 63.5). A total of 203 larvae from P. humeralis were isolates (P=65.71%; MI= 8.83; MA=5.8), 235 (P=54.29%; MI= 12.37; MA= 6.71) from C. variegatus, and 71 (P=42.86%; MI= 4.73; MA= 2.03) from P. adspersus. All adult and larval specimens were morphologically identified as C. australe. They were generated cytochrome c oxidase subunit 1 (cox1) gene sequences of specimens and were compared with available data from GenBank. Molecular phylogenetic analysis supported our morphological identification, where the Peruvian isolates formed a clade with other isolates of C. australe from other countries of the American continent. Of the sequences obtained, two haplotypes were detected and were not identical with previous reports. Based on both DNA barcoding and morphological analyses, our finding represents the first molecular data of C. australe from Peru and the report of Cheilodactylus variegatus as a new paratenic host on the central coast, extending the knowledge and distribution range of this acanthocephalan in Southeastern Pacific Ocean., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Spasticity is a frequent symptom of multiple sclerosis (MS), which may negatively influence daily living activities (ADL)., Objectives: To (1) explore the feasibility to conduct a structured interview by specialist nurses about limitations in ADL; (2) determine the percentage of people with MS (PwMS) with limitations in ADL related to spasticity; (3) to assess the knowledge about spasticity and describe its clinical features., Design: Observational, cross-sectional, multicentre study in 16 MS units of Catalonia (Spain). Participants were recruited from the outpatient facility and day-care hospital between July 2018 and June 2019 and met the following criteria: (1) age 18 or older, (2) diagnosis of MS according to McDonald criteria 2010 and (3) no clinical relapse in previous 30 days., Methods: Specialist nurses conducted a structured interview divided in two parts: the assessment of (1) limitations in the ADL and (2) the presence of spasticity and associated symptoms. The usefulness of this intervention was requested. This study met the STROBE reporting guidelines checklist for observational studies., Results: Three hundred sixty eight pwMS (244 women) with a mean age of 46 years and a median Expanded Disability Status Scale score of 2.5 (range, 0-8.5) were included. 262 (71%) pwMS had limitations in the ADL, and spasticity was reported as the most limiting symptom in 59 (23%). As a result of the interview, spasticity was observed in 199 (76%) participants; 47 (24%) of them were unaware that they had spasticity and 102 (51%) would not have reported it spontaneously. The level of the interview satisfaction was high (90%)., Conclusions: Spasticity is a complex and limiting symptom in MS. The structured interview conducted by specialist nurses is feasible and has good acceptance., Patient Contribution: Specialist nurses can be proactive in MS clinical assessment, which may help to detect symptoms with negative impact on quality of life., (© 2022 John Wiley & Sons Ltd.)

Introduction and Objectives: Transcatheter aortic valve implant has become a widely accepted treatment for inoperable patients with aortic stenosis and patients at high surgical risk. Its indications have recently been expanded to include patients at intermediate and low surgical risk. Our aim was to evaluate the efficiency of SAPIEN 3 vs conservative medical treatment (CMT) or surgical aortic valve replacement (SAVR) in symptomatic inoperable patients at high or intermediate risk., Methods: We conducted a cost-effectiveness analysis of SAPIEN 3 vs SAVR/CMT, using a Markov model (monthly cycles) with 8 states defined by the New York Heart Association and a time horizon of 15 years, including major complications and management after hospital discharge, from the perspective of the National Health System. Effectiveness parameters were based on the PARTNER trials. Costs related to the procedure, hospitalization, complications, and follow-up were included (euros in 2019). An annual discount rate of 3% was applied to both costs and benefits. Deterministic and probabilistic sensitivity analyses (Monte Carlo) were performed., Results: Compared with SAVR (high and intermediate risk) and CMT (inoperable), SAPIEN 3 showed better clinical results in the 3 populations and lower hospital stay. Incremental cost-utility ratios (€/quality-adjusted life years gained) were 5471 (high risk), 8119 (intermediate risk) and 9948 (inoperable), respectively. In the probabilistic analysis, SAPIEN 3 was cost-effective in more than 75% of the simulations in the 3 profiles., Conclusions: In our health system, SAPIEN 3 facilitates efficient management of severe aortic stenosis in inoperable and high- and intermediate-risk patients., (Copyright © 2021 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.)

This work presents data coming from electronic structure calculations at the Density Functional Theory level, performed in a series of organic photovoltaic materials. The data represents the Cartesian coordinates of such molecular systems at the lowest energy geometry and at the first excited state. Data evidencing the nature of the photo-isomerization in the OPV systems was also obtained. Additionally, the highest probabilities of the molecular electronic transitions giving rise to the absorption spectra observed in excited state were also computed. These data may aid to estimate photovoltaic parameters, and to tailor materials intended to be implemented in solar cell devices. They may also be used as input to design a training set for machine learning analysis and artificial intelligence., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have, or could be perceived to have, influenced the work reported in this article., (© 2021 The Author(s).)

In this study, we report the novel energy behavior of high-performance nanostructured materials in a segmented thermoelectric micro-generator (TEG). Several physical elements of the materials must be considered to determine their behavior in the thermoelectric energy conversion: temperature dependence of material properties, geometric structure, segmentation, and the symmetry of each or both p-type and n-type nanostructure semiconductor thermoelements. Recently, many efforts have reported effects independent on the thermoelectric performance of semiconductor materials. In this work, exhaustive research on the performance of high-performance nanostructured materials in a segmented thermoelectric micro-generator (TEG) was carried out. Our results show the efficiency and output power of the TEG using the temperature-dependent model, i.e., a variable internal resistance for a load resistance of the system. Our approach allows us to analyze symmetrical and asymmetric geometries, showing maximum and minimum peaks values in the performance of the TEG for specific [Formula: see text] values. The performance of the TEG is improved by about [Formula: see text] and [Formula: see text], for efficiency, and output power, respectively, considering a trapezoidal geometric shape in the 2p-3n segmented system, compared with the conventional rectangular shape.

An observational and descriptive study including patients discharged for COVID-19 was carried out by the COVID-19 Working Group of the Hospital Clínico San Carlos (HCSC). We aimed to identify the main symptoms after 90 days of hospital discharged. A structured interview was conducted, through a "checklist" that included symptoms within the 90 days post-discharge. A total of 134 patients were enrolled. The most frequently referred symptoms were asthenia, dyspnea and weight loss. Anxiety was the most frequent psychological symptom found through the GAD-7 scale., Competing Interests: The authors declare no competing interests., (Copyright: Miguel Suárez-Robles et al.)

This article contains data on nanoporous carbon materials coming from lignocellulosic components. Such data is directly related to the research paper "Insights into the design of carbon electrodes coming from lignocellulosic components pyrolysis with potential application in energy storage devices: A combined in silico and experimental study" [1]. In this work, the geometrical parameters of nanoporous carbon systems were found with Molecular Dynamics (MD) simulations at the ReaxFF level. The tridimensional structures of such carbon systems are given in Cartesian coordinates. They were computed at different heating rates, simulating the conditions observed in pyrolysis processes of Agave angustifolia leaves, which were carried out in a solar furnace. Nanoporous carbon systems are characterized with radial distribution functions (RDF) and ring distribution profiles.

Thermoelectric coolers (TECs) can reach temperatures below that obtained with a steady-state current by applying an electrical current pulse which enables a transitory state in a Peltier device. This effect is known as supercooling. In this paper, we study characteristics parameters, such as the minimum cooling temperature and spatial temperature profile, in a TEC operated under current pulses and a cooling load ( Q c ) . Numerical analysis for a one-dimensional thermoelectric model of the cooling system is developed, and a novel MATLAB programming code is proposed for the transient state based on finite element analysis. We also investigate the influence of the thermoelement's length upon the cooling mechanism. A new parameter called the "characteristic cooling length" is proposed to describe the length in which the minimum cooling temperature occurs along the elements of a TEM. Results show the transient temperature profiles along the elements of the semiconductor P-type element, and a "characteristic cooling length" is characterized. We also propose a general principle, and the lowest cooling temperature values are obtained for a semiconductor's small length and variable pulse cooling load under current pulse operation. The present study will serve as guidance for the geometric design of TECs under current pulse operations.

In recent years the interest for the harvest of energy with micro thermoelectric generators ( μ TEG) has increased, due to its advantages compared to technologies that use fossil fuels. There are three ways to improve the performance of the device, by modifying its structure, type of material and operation control. In this study, the role of the load resistance R L on the performance of a μ TEG with nanostructured materials is investigated. The interaction of the load resistance with the thermoelements exhibits interesting features, arising from the coupling of the temperature-dependent electrical and thermal transport properties at different temperature ranges and the architecture of nanostructured thermoelectric materials. This coupling results in inflections on the efficiency, i.e., maximum and minimum values of the efficiency at higher temperatures, 600-900 K. We show the explicit dependence of the performance of the μ TEG in terms of the load resistance and discuss the underlying physics. The unusual features of the efficiency of nanostructured thermoelectric materials are a result of the behavior of the power factor and the nonequilibrium properties of the system. We also analyze the effect of the geometric shape of the thermoelements on the device. We determine the performance of the μ TEG, evaluating the generation power and its efficiency. The results show that the efficiency of the device can decrease or increase depending on the value of R L , while the power decreases with an increase of the load resistance.

In this work, the influences of the Thomson effect and the geometry of the p-type segmented leg on the performance of a segmented thermoelectric microcooler (STEMC) were examined. The effects of geometry and the material configuration of the p-type segmented leg on the cooling power ( Q c ) and coefficient of performance ( C O P ) were investigated. The influence of the cross-sectional area ratio of the two joined segments on the device performance was also evaluated. We analyzed a one-dimensional p-type segmented leg model composed of two different semiconductor materials, B i 2 T e 3 and ( B i 0.5 S b 0.5 ) 2 T e 3 . Considering the three most common p-type leg geometries, we studied both single-material systems (using the same material for both segments) and segmented systems (using different materials for each segment). The C O P , Q c and temperature profile were evaluated for each of the modeled geometric configurations under a fixed temperature gradient of Δ T = 30 K. The performances of the STEMC were evaluated using two models, namely the constant-properties material (CPM) and temperature-dependent properties material (TDPM) models, considering the thermal conductivity ( κ ( T ) ), electrical conductivity ( σ ( T ) ) and Seebeck coefficient ( α ( T ) ). We considered the influence of the Thomson effect on C O P and Q c using the TDPM model. The results revealed the optimal material configurations for use in each segment of the p-type leg. According to the proposed geometric models, the optimal leg geometry and electrical current for maximum performance were determined. After consideration of the Thomson effect, the STEMC system was found to deliver a maximum cooling power that was 5.10 % higher than that of the single-material system. The results showed that the inverse system (where the material with a higher Seebeck coefficient is used for the first segment) delivered a higher performance than the direct system, with improvements in the C O P and Q c of 6.67 % and 29.25 % , respectively. Finally, analysis of the relationship between the areas of the STEMC segments demonstrated that increasing the cross-sectional area in the second segment led to improvements in the C O P and Q c of 16.67 % and 8.03 % , respectively., Competing Interests: The authors declare no conflict of interest.

Colorectal cancer is the third most common form of cancer in developed countries and, despite the improvements achieved in its treatment options, remains as one of the main causes of cancer-related death. In this review, we first focus on colorectal carcinogenesis and on the genetic and epigenetic alterations involved. In addition, noncoding RNAs have been shown to be important regulators of gene expression. We present a general overview of what is known about these molecules and their role and dysregulation in cancer, with a special focus on the biogenesis, characteristics, and function of microRNAs. These molecules are important regulators of carcinogenesis, progression, invasion, angiogenesis, and metastases in cancer, including colorectal cancer. For this reason, miRNAs can be used as potential biomarkers for diagnosis, prognosis, and efficacy of chemotherapeutic treatments, or even as therapeutic agents, or as targets by themselves. Thus, this review highlights the importance of miRNAs in the development, progression, diagnosis, and therapy of colorectal cancer and summarizes current therapeutic approaches for the treatment of colorectal cancer.

Introduction: Neonatal sepsis is one of the main causes of death among newborn infants. Empirical antimicrobial treatment is based on epidemiological information and antimicrobial susceptibility tests. The objective of this study was to describe etiologic agents and their antimicrobial susceptibility among newborn infants with early-onset neonatal sepsis (EONS) or late-onset neonatal sepsis (LONS) at a Neonatal Intensive Care Unit., Methods: Cross-sectional study conducted at a tertiary referral hospital in Western Mexico. Determination of antimicrobial resistance of microorganisms isolated in blood or cerebrospinal fluid of patients with EONS or nosocomial LONS., Results: Yeasts and bacteria were isolated from 235 cultures corresponding to 67 events of EONS and 166 events of LONS. Of all isolates, the most common bacteria were Enterobacteriaceae (51.5%), followed by Streptococcus spp. in EONS, and by Staphylococcus spp. in LONS. Of all nosocomial Enterobacteriaceae, 40% were extended spectrum beta-lactamase producing bacteria. Among Staphylococcus species, resistance to oxacillin was recorded in 65.5%. Among Enterobacteriaceae (n: 121), resistance to amikacin, piperacillin-tazobactam, and meropenem was below 3%. Non-fermenting bacteria did not show resistance to amikacin, ciprofloxacin or cefepime; however, the number of isolates was scarce., Conclusions: The most commonly identified bacteria in EONS were Enterobacteriaceae (67.6%) and Streptococcus spp. (17.6%), and Enterobacteriaceae (44.9%) and Staphylococcus spp. (34.7%) in LONS. Forty percent ofnosocomial Enterobacteriaceae were extended spectrum beta-lactamase producing bacteria, and 65.5% of Staphylococcus spp. showed resistance to oxacillin.

Limited empirical evidence exists for how economic conditions affect micronutrient nutrition. We hypothesized that increasing poverty and rising food prices would reduce consumption of high-quality "luxury" foods, leading to an increased probability of inadequacy for several nutrients. The 2006 Guatemala National Living Conditions Survey was analyzed. First, energy and nutrient intakes and adequacy levels were calculated. Second, the income-nutrient relationships were investigated by assessing disparities in intakes, determining income-nutrient elasticities, and modeling nutrient intakes by reductions in income. Third, the food price-nutrient relationships were explored through determination of price-nutrient elasticities and modeling 2 price scenarios: an increase in food prices similar in magnitude to the food price crisis of 2007-2008 and a standardized 10% increase across all food groups. Disparities in nutrient intakes were greatest for vitamin B-12 (0.38 concentration index) and vitamin A (0.30 concentration index); these nutrients were highly and positively correlated with income (r = 0.22-0.54; P < 0.05). Although the baseline probability of inadequacy was highest for vitamin B-12 (83%), zinc showed the greatest increase in probability of inadequacy as income was reduced, followed by folate and vitamin A. With rising food prices, zinc intake was most acutely affected under both scenarios (P < 0.05) and folate intake in the poorest quintile (+7 percentage points) under the 10% scenario. Price-nutrient elasticities were highest for vitamin B-12 and the meat, poultry, and fish group (-0.503) and for folate and the legumes group (-0.343). The economic factors of food prices and income differentially influenced micronutrient intakes in Guatemala, notably zinc and folate intakes.

Background: From 2006 to 2008, there were sharp increases in the prices of major food commodities globally, including maize, rice, and wheat. Few studies have contributed empirical evidence of the nutritional impacts of this food price crisis., Objective: To assess changes in energy intake in response to food price shocks and in relation to calorie adequacy levels in seven Latin American countries., Methods: Data were drawn from nationally representative household budget surveys. The quadratic almost ideal demand system (QUAIDS) model characterized change patterns in consumption for six food groups and one nonfood group under two scenarios: actual change in food prices by country, and standardized 10% increase in prices across all countries. Energy intakes before and after the crisis were determined once calories were assigned to food items from the ProPAN and US Department of Agriculture food composition databases., Results: Energy intakes were reduced by 8.0% (range, 0.95% to 15.1%) from precrisis levels across all countries. Ecuador and Panama were the worst affected, followed by Haiti and Nicaragua. There was a consistent, direct relationship between wealth quintile and change in energy intake. Rural areas were affected to the same extent as or a greater extent than urban areas. High positive increases in calorie consumption were found in the richest wealth quintile, exceeding 10% of previous levels in five countries., Conclusions: Policies and programs targeting the poorest households in both rural and urban areas may be needed to offset the energy deficits associated with food price increases. More research is needed on the effect of food prices and micronutrient nutrition.

The question of whether the known virial coefficients are enough to determine the packing fraction η(∞) at which the fluid equation of state of a hard-sphere fluid diverges is addressed. It is found that the information derived from the direct Padé approximants to the compressibility factor constructed with the virial coefficients is inconclusive. An alternative approach is proposed which makes use of the same virial coefficients and of the equation of state in a form where the packing fraction is explicitly given as a function of the pressure. The results of this approach both for hard-disk and hard-sphere fluids, which can straightforwardly accommodate higher virial coefficients when available, lends support to the conjecture that η(∞) is equal to the maximum packing fraction corresponding to an ordered crystalline structure.

Steinernema carpocapsae is an insect parasitic nematode used in biological control, which infects insects penetrating by mouth and anus and invading the hemocoelium through the midgut wall. Invasion has been described as a key factor in nematode virulence and suggested to be mediated by proteases. A serine protease cDNA from the parasitic stage was sequenced (sc-sp-1); the recombinant protein was produced in an Escherichia coli system, and a native protein was purified from the secreted products. Both proteins were confirmed by mass spectrometry to be encoded by the sc-sp-1 gene. Sc-SP-1 has a pI of 8.7, a molecular mass of 27.3 kDa, a catalytic efficiency of 22.2 × 10(4) s(-1) m(-1) against N-succinyl-Ala-Ala-Pro-Phe-pNA, and is inhibited by chymostatin (IC 0.07) and PMSF (IC 0.73). Sc-SP-1 belongs to the chymotrypsin family, based on sequence and biochemical analysis. Only the nematode parasitic stage expressed sc-sp-1. These nematodes in the midgut lumen, prepared to invade the insect hemocoelium, expressed higher levels than those already in the hemocoelium. Moreover, parasitic nematode sense insect peritrophic membrane and hemolymph more quickly than they do other tissues, which initiates sc-sp-1 expression. Ex vivo, Sc-SP-1 was able to bind to insect midgut epithelium and to cause cell detachment from basal lamina. In vitro, Sc-SP-1 formed holes in an artificial membrane model (Matrigel), whereas Sc-SP-1 treated with PMSF did not, very likely because it hydrolyzes matrix glycoproteins. These findings highlight the S. carpocapsae-invasive process that is a key step in the parasitism thus opening new perspectives for improving nematode virulence to use in biological control.

Steinernema carpocapsae is an insect parasitic nematode able to parasitise and kill the host within 48 h. Secreted products (ESP) of the parasitic stage of a virulent strain contain higher amounts of proteolytic activity than a low virulence strain, suggesting proteases are involved in virulence. From the ESP we purified a protein (Sc-SP-3) with a M(r) of 30 kDa and a pI of 7 that cleaved the synthetic substrate N-succinyl-Ala-Ala-Pro-Phe-pNA and was inhibited by phenylmethanesulfonyl fluoride, benzamidine and chymostatin, thus indicating that it belongs to the chymotrypsin-like serine protease family. Sc-SP-3 has a V(max) of 0.3 mM min(-1)ml(-1) and K(m) of 6.6 x 10(-4)M, with maximum activity at pH 8 and 40 degrees C. The full-length cDNA was obtained using degenerate oligonucleotides for serine proteases. This open reading frame encodes a preproprotein containing a putative signal peptide composed of 16 amino acid residues, a prodomain of 40 residues and a mature protease domain of 261 residues, including the catalytic triad His/Asp/Ser characteristic of trypsin-like serine proteases. The N-terminal sequence and the peptide masses fingerprint obtained by MALDI-TOF-MS for the purified protein matched the cDNA. Gene expression analysis by quantitative real-time-PCR showed that this gene is expressed only during the parasitic stage and that pre-invasive nematodes inside the mid-gut expressed higher amounts of Sc-SP-3 than those that already enter the haemocoel. Sc-SP-3 caused histolysis in the insect mid-gut. In vitro assays demonstrated that Sc-SP-3 digested extracellular proteins and induced apoptosis in Sf9 insect cells, thus suggesting Sc-SP-3 is a multifunctional chymotrypsin-like protease involved in pathogenesis.

A study was conducted in 2006 to determine the prevalence of Salmonella on three cantaloupe farms in Matamoros, Coahuila, Mexico, and on one farm that cultivates chile peppers var. Bell in Culiacán, Sinaloa, Mexico. Samples from cantaloupe farms consisted of cantaloupe rinses, irrigation water, water from furrows in the field, and workers' hands. Samples from the chile pepper farm consisted of rinses of chile peppers obtained at the field, pepper rinses obtained at the packing house, and irrigation water from the field. A total of 55 samples were obtained from both production systems. Twelve and 10 samples from the cantaloupe and chile pepper production systems, respectively, tested positive for Salmonella according to a traditional culture method. The difference between the proportion of Salmonella-positive samples from the cantaloupe production system (12 of 28 = 0.43) and the chile pepper production system (10 of 27 = 0.37) was not statistically significant (P > 0.05). A PCR-restriction fragment length polymorphism (RFLP) method based on the fliC gene was used to determine the serotype of the isolates. Salmonella Typhimurium was the only serotype found associated with the cantaloupe production system, whereas both Salmonella Typhimurium and Enteritidis serotypes were found associated with the chile pepper production system. Results showed that 91% (20 of 22) and 9% (2 of 22) of the isolates from both agricultural systems matched with the Salmonella Typhimurium and Salmonella Enteritidis reference strain restriction profiles, respectively. This study demonstrates the utility of the PCR-RFLP technique for determining the serotypes of Salmonella isolates obtained from cantaloupe and chile pepper production systems.

A recently derived method [R. D. Rohrmann and A. Santos, Phys. Rev. E 76, 051202 (2007)] to obtain the exact solution of the Percus-Yevick equation for a fluid of hard spheres in (odd) d dimensions is used to investigate the convergence properties of the resulting virial series. This is done both for the virial and compressibility routes, in which the virial coefficients B(j) are expressed in terms of the solution of a set of (d-1)/2 coupled algebraic equations which become nonlinear for d>/=5. Results have been derived up to d=13. A confirmation of the alternating character of the series for d>/=5, due to the existence of a branch point on the negative real axis, is found and the radius of convergence is explicitly determined for each dimension. The resulting scaled density per dimension 2eta(1/d), where eta is the packing fraction, is wholly consistent with the limiting value of 1 for d-->infinity. Finally, the values for B(j) predicted by the virial and compressibility routes in the Percus-Yevick approximation are compared with the known exact values [N. Clisby and B. M. McCoy, J. Stat. Phys. 122, 15 (2006)].

The direct correlation function and the (static) structure factor for a seven-dimensional hard-sphere fluid are considered. Analytical results for these quantities are derived within the Percus-Yevick [Phys. Rev.110, 1 (1958)] theory.

Following the work of Leutheusser [Physica A 127, 667 (1984)], the solution to the Percus-Yevick equation for a seven-dimensional hard-sphere fluid is explicitly found. This allows the derivation of the equation of state for the fluid taking both the virial and the compressibility routes. An analysis of the virial coefficients and the determination of the radius of convergence of the virial series are carried out. Molecular-dynamics simulations of the same system are also performed and a comparison between the simulation results for the compressibility factor and theoretical expressions for the same quantity is presented.