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People spend increasing amounts of time at home, yet the indoor home environment remains understudied in terms of potential exposure to toxic trace metals. We evaluated trace metal (and metalloid) concentrations (As, Cu, Cr, Mn, Ni, Pb, and Zn) and health risks in indoor dust from homes from 35 countries, along with a suite of potentially contributory residential characteristics. The objective was to determine trace metal source inputs and home environment conditions associated with increasing exposure risk across a range of international communities. For all countries, enrichments compared to global crustal values were Zn > Pb > Cu > As > Cr > Ni; with the greatest health risk from Cr, followed by As > Pb > Mn > Cu > Ni > Zn. Three main indoor dust sources were identified, with a Pb–Zn–As factor related to legacy Pb sources, a Zn–Cu factor reflecting building materials, and a Mn factor indicative of natural soil sources. Increasing home age was associated with greater Pb and As concentrations (5.0 and 0.48 mg/kg per year of home age, respectively), as were peeling paint and garden access. Therefore, these factors form important considerations for the development of evidence-based management strategies to reduce potential risks posed by indoor house dust. Recent findings indicate neurocognitive effects from low concentrations of metal exposures; hence, an understanding of the home exposome is vital. © 2021 The Authors. Published by American Chemical Society

Water hyacinth Eichhornia crassipes is considered the most damaging aquatic weed in the world. However, few studies have quantified the impact of this weed economically and ecologically, and even fewer studies have quantified the benefits of its control. This paper focuses on water loss saving as the benefit derived from biological control of this plant between 1990 and 2013 at New Year’s Dam, Alicedale, Eastern Cape, South Africa. Estimates of water loss due to evapotranspiration from water hyacinth vary significantly; therefore, the study used three different rates, high, medium and low. A conservative raw agriculture value of R 0.26 per m3 was used to calculate the benefits derived by the water saved. The present benefit and cost values were determined using 10% and 5% discount rates. The benefit/cost ratio at the low evapotranspiration rate was less than one, implying that biological control was not economically viable but, at the higher evapotranspiration rates, the return justified the costs of biol...

Purpose The primary driver of poor outcomes in the early stages of lung transplantation is primary graft dysfunction (PGD). Patients with cystic fibrosis (CF) have unique physiology and demographics compared to other lung transplant recipients. Therefore, we sought to identify risk factors for PGD in the CF patient population undergoing lung transplantation. Methods We utilized clinical data on lung transplant recipients with CF and their donors from the Lung Transplant Outcomes Group cohort, a multi-center prospective cohort study of PGD pathogenesis. The primary outcome was grade 3 PGD within the first 72 hours after transplantation. Potential covariates were identified in univariate analysis and assessed for collinearity. Independent PGD risk factors were identified using multivariate logistic regression. A sensitivity analysis was performed using grade 3 PGD 48 to 72 hours after transplantation. Results We identified 195 patients with CF who received lung transplants between August 2014 and June 2018 across ten centers. Grade 3 PGD developed in 80 subjects (41%). Risk factors for PGD in CF patients based on the multivariable model were white donor race (odds ratio [OR]: 2.6, 95% confidence interval [CI]: 1.4-5.1), any positive panel reactive antibodies (PRA) (OR: 2.2, 95% CI: 1.0-4.7), recipient female gender (OR: 2.1, 95% CI: 1.1-3.9), intraoperative cardiopulmonary bypass use (OR: 2.2, 95% CI: 1.2-4.2), increasing lung allocation score (LAS) (OR: 1.2 per 10 point increase in LAS, 95% CI: 1.0-1.4), and ECMO (extracorporeal membrane oxygenation) bridge to transplant (OR: 2.7, 95% CI: 1.1-6.7). LAS and ECMO were assessed in separate models due to their collinearity. Mean pulmonary artery pressure at the time of transplant was included as a potential confounder. Similar findings were seen in a more severe phenotype of PGD that developed 48 to 72 hours after transplant. Conclusion The CF population is often considered to be at low risk of PGD, however we observed a relatively high rate of PGD in this study. Any positive PRA, female recipient gender, intraoperative bypass, increasing LAS, and ECMO are PGD risk factors that have been identified non-CF transplant populations. We validated these risk factors in recipients with CF. White donor race is a novel risk factor that has not been previously identified in lung transplant recipients with another primary diagnosis.

In this study, the authors present a technique for code acquisition in optical code-division multiple-access systems using the recently introduced random optical codes. In these systems, the communication is divided in two parts: a synchronisation process and the data transmission. The main target of the study is to describe and analyse the new algorithm of synchronisation using Markov processes. Once described the code acquisition technique and established an estimation for the probability of false alarm (FA) of the proposed scheme, two different proposals for the optimisation of the code parameters are described. They are based on two different estimators for the probability of FA. The first one considers the expected value for the probability of FA. The second one is very much restrictive. It guarantees that the probability of FA is in a confidence interval. It takes the upper bound of the confidence interval as estimator for the probability of FA. Although the second one presents worse acquisition time, the authors consider that the gain provided by the first method is not sufficient enough to assume its loss in the reliability. Thus, the authors propose to guarantee the probability of FA in a confidence interval. A compromise between reliability and acquisition time is obtained with this second method.

This paper presents a novel clustering technique that has been applied to plasma signals to show its utility. It is a general method based on a partitioning scheme that has been proven to be efficient for purposes of analysis and processing of fusion plasma waveforms. Moreover, this paper shows how the information given by the clustering can be used to produce a concise and representative model of each class of signals by applying different modeling approaches. Neuro-fuzzy identification and time-domain techniques have been used. These models allow the application of procedures to detect anomalous behaviors or interesting events within a continuous data flow that could automatically trigger the execution of some experimental procedures. Previously, an in-depth analysis and a preprocessing phase of the waveforms have been carried out. These procedures have been applied to plasma signals of the TJ-II Stellarator fusion device with encouraging results.

This paper describes a numerical data set comprising the three-dimensional fracture network of a 1 m 3 block of Bodmin granite. The data set can be downloaded from the following web sites: www.elsevier.com/ijrmms , www.leeds.ac.uk/StochasticRockFractures and www.ecms.adelaide.edu.au/civeng/research/StochasticRockFractures . The purpose of this paper is to provide the scientific community with a true data set that can be used to validate models and simulations of fractured crystalline rock masses. The methodology for procuring additional data sets is also described.

The determinants of binding of a peptide lacking C-termini-exposed lysine residues to a kringle domain were investigated using an up-regulated lysine binding kringle (K2Pg[C4G/E56D/K72Y]) of plasminogen and a peptide (a1-PAM) with a sequence derived from a surface-exposed M-like streptococcal protein. Significant kringle-induced chemical shifts in a His side-chain of a1-PAM were revealed by two-dimensional NMR. Further studies using isothermal titration calorimetry (ITC) provided support for the involvement of His12 in the peptide/ protein complex. In an effort to screen a1-PAM-derived truncation peptides, a combinatorial mixture, a1deltaa2-PAM[H12X] (where X=Pro, Arg, His, Trp, Lys, Ala, Phe, Asp and Gly), was analyzed using the surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI) platform. The major peptide that remained bound to the surface of the K2Pg[C4G/ E56D/K72Y]-containing chip was that containing His12, corresponding to the wild-type sequence. Minor peaks, representing binding, were obtained for Lys12-, Arg12- and Trp12-containing peptides. Individual peptides containing these amino acids were then examined using ITC and the binding constants obtained correlated with the relative strengths of binding estimated from the SELDI-based screen.

Laboratory cutting tests have been performed in hard rock utilising an instrumented SO tonne capacity rock planer. The experiment involved intermittent cutting of felsic gneiss up to a maximum of 20 m or until tool failure, Each cutting tool was fitted with a thermocouple in the tungsten carbide insert to monitor the insert tip temperature. The cutting forces and tool wear were also monitored. Cutting was conducted with and without high pressure water jet assistance (HPWJA). The results show that a dependence exists between the tool temperature and the tool normal force component. HPWJA enhances the tool life and acts as a heat sink during cutting. An elementary model is proposed to explain the findings and provide a theoretical basis for anticipating high tool wear.

In recent years, spacial agencies have shown a growing interest in optical wireless as an alternative to wired and radio-frequency communications [1,2]. The use of these techniques for intra-spacecraft communications reduces the effect of take-off acceleration and vibrations on the systems by avoiding the need for rugged connectors and provides a significant mass reduction. Diffuse transmission also eases the design process as terminals can be placed almost anywhere without a tight planification to ensure the proper system behaviour. Previous studies [3,4] have compared the performance of radio-frequency and infrared optical communications. In an intra-satellite environment optical techniques help reduce EMI related problems, and their main disadvantages - multipath dispersion and the need for line-of-sight - can be neglected due to the reduced cavity size. Channel studies [5] demonstrate that the effect of the channel can be neglected in small environments if data bandwidth is lower than some hundreds of MHz.

In this paper we show that the effect of jitter due to driver and LED is the limiting factor in the baud rate in L-PPM formats for VLC systems.

An infrared optical wireless system is presented, consisting on autonomous remote nodes communicating with a central node. The network is designed for telecommand/telemetry purposes, comprising a large number of nodes at a low data rate. Simultaneous access is granted by using CDMA techniques, and an appropriate selection of the code family can also keep power consumption to a minimum.

Silicon has been deposited on Si(111) under UHV by means of the pulsed laser evaporation technique. The evaporated species contain Si ions of kinetic energies as high as 2 keV, i.e. much higher than in thermal evaporation. STM images of around 0.1 deposited monolayers reveal that some damage is produced on the substrate. The damaged areas consist mainly in monatomic vacancies of the so-called internal adatoms in the unit cell. Triangular islands of lateral dimensions around 100 A along [110] directions have been found at variance with previous published results on thermal evaporation. The atomic density of the islands appears to be smaller than that of the substrate and they contain rows of paired atoms.

During 2004 and 2005, over 38,000km of 2D non-exclusive data were acquired in the waters offshore Libya in cooperation with NOC and NAGECO. This consistent dataset provides regional correlation from the existing developed western fields into the largely un-explored offshore Gulf of Sirt and Cyrenaica regions. It provides a unique resource for reviewing the potential of some of the world’s most prospective acreage and complements NOC in their efforts to boost Exploration in Libyan waters.

We report 3 cases of ureterocele associated with ureteral triplication and review the literature. Ureteral triplication was type I in 2 patients and type II in 1. Diagnosis was established preoperatively in 2 cases and intraoperatively in 1. All patients were initially treated by upper pole partial nephrectomy and aspiration of the ureterocele, leaving the ureteral stump open in the retroperitoneum. Subsequent excision of the ureterocele and ureteral reimplantation for persistent ipsilateral vesicoureteral reflux and recurrent urinary tract infections were required in 2 cases.

We propose a novel family of optical codes to be used in intra-satellite optical wireless networks. They are algorithm optical codes (ADCs). This family is related with the recently introduced family random optical codes (ROCs). Both families of codes are designed to be used in optical code-division multiple-access (OCDMA) systems. Similarly than their predecessor, i.e. ROCs, ADCs are specially suitable for optical networks where the number of channels varies, ever large, low bit rate requirements, energy limitations and packed data are presented. For example sensor networks demand these requirements. A detailed description of AOCs is shown in this paper. Furthermore a comparison between them and ROCs is presented. We find that AOCs provide less probability of error than ROCs, for a given length of the code and a number of users. Moreover a system using AOCs can change the length of the code easier than a system using ROCs. This fact permits a more efficient accommodation to the actual number of users. Finally the implementation in an intra-spacecraft telecommand and telemeasurement (TC/TM) optical wireless network is also described. We compare the families in the intra-spacecraft optical wireless network.

The present study shows that an an O-atom translation energy of 1.5 eV, SO 2 is generated and outgases from an anhydrous MoS 2 surface with an initial reactivity nearly 50% that of kapton. The reaction of atomic oxygen with MoS 2 has little or no translational energy barrier, i.e. thermally generated atomic oxygen reacts as readily as that having 1.5 eV of translational energy. For MoS 2 films sputter-deposited at 50–70 °C, friction measurements showed a high initial friction coefficient (up to 0.25) for MoS 2 surfaces exposed to atomic oxygen, which dropped to the normal low values after several cycles of operation in air and ultrahigh vacuum. For MoS 2 films deposited at 200 °C, the friction coefficient was not affected by the O-atom exposure.

We present a novel family of optical codes to be used in intra-satellite optical wireless networks. They are random optical codes (ROCs). This family is specially adapted for optical networks where the number of channels varies, ever large, low bit rate requirements, energy limitations and packed data are present. For example sensor networks have these requirements. The implementation in an intra-spacecraft telecommand and telemeasurement (TC/TM) optical wireless network is also described. Besides we propose a method for the comparison between ROCs and generalized optical orthogonal codes (OOCs). A decision between both family based on the performance for a particular set of parameters is given by the method. An application of the method is also provided. We have compared the families in the intra-spacecraft optical wireless network.

This work presents the application of optical orthogonal codes (OOC) for intra-spacecraft communications within a sensor network with a large number of terminals. In particular, a novel family of optical codes named random optical codes is introduced for the target application. These codes allow a simple optimization of the length and weight of the code while maintaining a controlled probability of error and a low duty cycle. Also, due to a straightforward generation process they can be adjusted almost in real-time to adapt to new conditions like including new channels. This flexibility makes this family a good candidate for systems with strict restrictions over this parameters.

Percutaneous ultrasound-guided pancreas allograft biopsy is the preferred technique for evaluating pancreas allograft rejection. Experience from large centers has shown it to be safe and effective. We report our experience with 120 percutaneous allograft biopsies performed at a single center. Biopsy tissue was obtained in 54 patients. Thirty-three patients received simultaneous pancreas and kidney transplants, 14 received isolated pancreas transplants, and 7 received a pancreas transplant after kidney transplantation. Biopsies were performed by pancreas transplantation surgeons with the assistance of radiologists under ultrasound guidance using an Acuson XP 128/10 ultrasound machine. One hundred twenty allograft biopsies were performed in 54 patients. Twenty-seven (50%) patients underwent multiple biopsies. In 102 (85%) biopsies the specimens were adequate for examination. Eighteen (15%) biopsy samples had no pancreatic tissue and showed surrounding fat and small bowel. 1 (1.8%) patient bleeding developed that required transfusion of 3 units of packed red blood cells, but no surgical intervention was necessary. One (1.8%) patient had a pancreatic fistula, which healed with nonoperative management. Biochemical evidence of pancreatitis was noted in 5 (9.2%) patients, but none of these patients had clinical signs of pancreatitis. Percutaneous ultrasound-guided pancreas allograft biopsy is a safe procedure with a low complication rate and a high tissue yield for histopathologic examination.

This paper reports a model of the mammalian retina as well as an interpretation of some functions of the visual cortex. Its main objective is to simulate some of the behaviors observed at the different retina cells depending on the characteristics of the light impinging onto the photoreceptors. This simulation is carried out with a simple structure employed previously as basic building block of some optical computer architectures. Its possibility to perform any type of Boolean function allows a wide range of behaviors.

Objective The objective of this study is to assess a Simulect (basiliximab) regimen in routine clinical practice in the Spanish kidney transplantation units to evaluate efficacy and safety. Methods In this prospective, observational study, data on demographics, parameters of efficacy, and safety in patients who under with kidney transplantation treated with Simulect (basiliximab) were collected through an on-line collection system. Results One hundred sixty three patients at 18 kidney transplant units included 12 months follow-up. The patient mean age was 52 years (DS 13,67) including 96 (58.90%) men and 67 (41.10%) women. Cold ischemia time was 19 hours (DS 6,79). Only 2 patients presented with PRA >50%. For prophylactic immunosuppression, 67.13% of patients received triple therapy with CNI (cyclosporine 49.65% or tacrolimus 17.48%), MMF (66.43%) or AZA (10.49%), and steroids. Incidence of acute rejection (AR) at 12 months was 12.27% (1.84% steroid-resistant). In subgroup analysis, AR was 13.5% in nondiabetics and 4.5% in diabetics, including 3 steroid-resistant episodes (1.84%) in nondiabetics and none in diabetics. In relation to donor age, AR was incidence 10.3% in patients with kidneys from donors aged 50 years or younger and 10.6% when donors were older than 50 years, including 1 (1.73%) and 2 (1.93%) steroid-resistant episodes, respectively. The graft and patient survival rates at 12 months were 90% and 98%, respectively. Conclusions Simulect (basiliximab) used in routine clinical practice provided good prophylaxis against acute rejection in several kidney transplant patient populations, similar to that observed in randomized clinical studies with excellent tolerability and safety.

An electromyographic (EMG) analysis of eight leg muscles when riding a stepper bike at various workloads in both the seated and standing positions is presented.

The notion of an RSS (relational semantic system) as a set of atomic propositions evaluated in the unit interval and functions representing complementation (negation n) and logical intersection (junctor j) is introduced. This concept is used to determine under what circumstances the models of fuzzy approximate reasoning can be embedded in a probability space. This situation includes most of the classical fuzzy-set-theoretical approaches. A straightforward way of representing the concept of conditioning for most fuzzy measures is obtained. >