From Materials to Cell: State-of-the-Art and Prospective Technologies for Lithium-Ion Battery Electrode Processing.

Electrode processing plays an important role in advancing lithium-ion battery technologies and has a significant impact on cell energy density, manufacturing cost, and throughput. Compared to the extensive research on materials development, however, there has been much less effort in this area. In this Review, we outline each step in the electrode processing of lithium-ion batteries from materials to cell assembly, summarize the recent progress in individual steps, deconvolute the interplays between those steps, discuss the underlying constraints, and share some prospective technologies. This Review aims to provide an overview of the whole process in lithium-ion battery fabrication from powder to cell formation and bridge the gap between academic development and industrial manufacturing.

Efficacy of levamisole, ivermectin and moxidectin against Capillaria spp. in European hedgehogs (Erinaceus europaeus).

This randomised study aimed to assess and compare the efficacy of treatment protocols containing levamisole, ivermectin, or moxidectin against Capillaria spp. in naturally infected European hedgehogs (Erinaceus europaeus) presented to a British wildlife rehabilitation centre. Faecal analysis, consisting of wet mount and flotation, was performed for 229 hedgehogs weighing ≥200g. Animals testing positive for Capillaria spp. (81%), excluding pregnant females, were randomly allocated a treatment protocol. Initially, hedgehogs (n = 50) received one of six 'pilot' protocols, whereas the remaining animals (n = 97) received one of three 'main' protocols. Faecal analysis was repeated on day 8 and day 12 after treatment initiation. Efficacy of each treatment was assessed based on Capillaria reduction rate (CRR), weight gain, presence of respiratory clinical signs, and outcome. Pilot protocols containing only moxidectin had a significantly lower CRR (≥28.1%) compared to those with levamisole or ivermectin (≥86.6%), whereas the main protocols containing levamisole had a significantly higher CRR (≥93.0%) compared to those containing only ivermectin (≥69.3%). Clinical parameters did not differ significantly between treatments, but animals with respiratory clinical signs at the end of the trial were significantly more likely to have lower CRR and test positive for Crenosoma striatum. C. striatum often appeared refractory to treatment, and managing these infections requires additional anthelmintic therapy. Based on the formulations and dosages trialled, moxidectin is not recommended for treating capillariosis in European hedgehogs, whereas levamisole given orally for two consecutive days at 25-35 mg/kg is suggested as the treatment of choice.

Administration of an oxytocin receptor antagonist attenuates sexual motivation in male rats.

In male rats, oxytocin impacts both sexual arousal and certain types of consummatory sexual behaviors. However, the role of oxytocin in the motivational aspects of sexual behavior has received limited attention. Given the role that oxytocin signaling plays in consummatory sexual behaviors, it was hypothesized that pharmacological attenuation of oxytocin signaling would reduce sexual motivation in male rats. Sexually experienced Long-Evans male rats were administered either an oxytocin receptor antagonist (L368,899 hydrochloride; 1mg/kg) or vehicle control into the intraperitoneal cavity 40min prior to placement into the center chamber of a three-chambered arena designed to assess sexual motivation. During the 20-minute test, a sexually experienced stimulus male rat and a sexually receptive stimulus female rat were separately confined to smaller chambers that were attached to the larger end chambers of the arena. However, physical contact between test and stimulus rats was prevented by perforated dividers. Immediately following the sexual motivation test, test male rats were placed with a sexually receptive female to examine consummatory sexual behaviors. Although both drug and vehicle treated rats exhibited a preference for the female, treatment with an oxytocin receptor antagonist decreased the amount of time spent with the female. There were no differences between drug and vehicle treated rats in either general activity, exploratory behaviors, the amount of time spent near the stimulus male rat, or consummatory sexual behaviors. Extending previous findings, these results indicate that oxytocin receptors are involved in sexual motivation in male rats.

Aqueous Ni-rich-cathode dispersions processed with phosphoric acid for lithium-ion batteries with ultra-thick electrodes.

Lithium-ion battery (LIB) production can benefit both economically and environmentally from aqueous processing. Although these electrodes have the potential to surpass electrodes conventionally processed with N-methyl-2-pyrrolidone (NMP) in terms of performance, significant issues still exist with respect to ultra-thick cathodes (≫4 mAh/cm2 areal capacities). A major concern for these types of electrodes with high-nickel active material stems from lithium leaching from active material, which drives the pH of the dispersion in excess of 12 and subsequently corrodes the current collector interface. As this corrosion reaction proceeds, hydrogen generation at the interface creates bubbles which cause severe cracking in the dried electrode surface. When areal loadings are increased, this effect becomes more pronounced and is detrimental to both mechanical and electrochemical properties of these electrodes. Herein, a technique for mitigating corrosion at the current collector by adjusting the pH of the dispersion with the addition of phosphoric acid is investigated. Phosphoric acid was added in 0.5 wt% increments between 0.0 and 1.5 wt%, and effects on rheology, adhesion, corrosion, and electrochemical performance were investigated. A technique is reported for producing aqueous processed cathodes with areal loadings of 6-8 mAh/cm2 with reduced surface cracking and superior high-rate discharge capacity (i.e. high-power performance) for this class of cathode loadings.

Aedes albopictus in North America: probable introduction in used tires from northern Asia.

North American strains of Aedes albopictus, an Asian mosquito recently introduced into the Western Hemisphere, exhibit photoperiodic sensitivity and cold-hardiness characteristics similar to strains originating from temperate zone Asia. Trade statistics for used tire imports, the most likely mode of introduction, also indicate a north Asian origin. Aedes albopictus, an important vector of dengue and a potential vector of many other arboviral diseases, may therefore have the capability of infesting much of temperate North America.

The role of estrogen G-protein coupled receptor 30 (GPR30) and sexual experience in sexual incentive motivation in male rats.

Male rats exhibit reductions in sexual motivation following systemic administration of drugs that inhibit the conversion of testosterone to estrogen, which indicates that estrogen signaling plays a role in male rat sexual motivation. Given that estrogen G-protein coupled receptor 30 (GPR30) is expressed in brain areas that are important for male sexual behaviors and endocrine function, the primary aim of the current study was to examine the role that GPR30 plays in sexual motivation in both sexually naïve and sexually experienced male rats. Following the final treatment with either a GPR30 antagonist (G-15) or vehicle control, male rats were placed into the center chamber of a larger three-chambered testing arena that was designed to assess sexual incentive motivation. A sexually receptive stimulus female rat and a stimulus male rat were individually confined to one of the two smaller chambers that were each separated by a perforated partition from the larger end chambers, which test rats had access to. Relative to vehicle treated rats, male rats treated with G-15 exhibited a reduction in the percentage of time spent in the vicinity of a sexually receptive female rat. Although G-15 reduced sexual incentive motivation independent of sexual experience, only sexually-naïve rats treated with G-15 did not exhibit a preference for the sexually receptive stimulus female rat. Collectively, these results indicate that interference with estrogen signaling at GPR30 reduces sexual motivation and that the lack of preference for a sexually receptive female rat over a male rat following G-15 treatment is abrogated by previous sexual experience.

Impact of sustained use of insecticide-treated bednets on malaria vector species distribution and culicine mosquitoes.

Insecticide-treated bednets (ITNs) significantly reduce malaria vector populations. Susceptibility to ITNs differs by vector species, and culicine mosquitoes have not been shown to be significantly affected by the use of ITNs. We examined the impact of 2-4 yr of ITN use on malaria vector species distribution and culicine mosquitoes. Routine entomological surveillance was conducted in adjacent areas with and without ITNs from November 1999 to January 2002. Use of ITNs reduced the proportion of Anopheles gambiae Giles relative to Anopheles arabiensis Giles. The number of culicines per house was significantly lower in the ITN area than in the neighboring area. Changes in the An. gambiae sibling species distribution may help to explain apparent mosquito behavioral changes attributed to ITNs. Reductions in culicines by ITNs may have implications for community perceptions of ITN effectiveness and for control of other diseases such as lymphatic filariasis.

An evaluation of evolutionary constraints on microsatellite loci using null alleles.

A test to evaluate constraints on the evolution of single microsatellite loci is described. The test assumes that microsatellite alleles that share the same flanking sequence constitute a series of alleles with a common descent that is distinct from alleles with a mutation in the flanking sequence. Thus two or more different series of alleles at a given locus represent the outcomes of different evolutionary processes. The higher rate of mutations within the repeat region (10(-3) or 10(-4)) compared with that of insertion/deletion or point mutations in adjacent flanking regions (10(-9)) or with that of recombination between the repeat and the point mutation (10(-6) for sequences 100 bp long) provides the rationale for this assumption. Using a two-phase, stepwise mutation model we simulated the evolution of a number of independent series of alleles and constructed the distributions of two similarity indices between pairs of these allele series. Applying this approach to empirical data from locus AG2H46 of Anopheles gambiae resulted in a significant excess of similarity between the main and the null series, indicating that constraints affect allele distribution in this locus. Practical considerations of the test are discussed.

Patterns of mitochondrial variation within and between African malaria vectors, Anopheles gambiae and An. arabiensis, suggest extensive gene flow.

Anopheles gambiae and An. arabiensis are mosquito species responsible for most malaria transmission in sub-Saharan Africa. They are also closely related sibling species that share chromosomal and molecular polymorphisms as a consequence of incomplete lineage sorting or introgressive hybridization. To help resolve these processes, this study examined the partitioning of mtDNA sequence variation within and between species across Africa, from both population genetic and phylogeographic perspectives. Based on partial gene sequences from the cytochrome b, ND1 and ND5 genes, haplotype diversity was high but sequences were very closely related. Within species, little or no population subdivision was detected, and there was no evidence for isolation by distance. Between species, there were no fixed nucleotide differences, a high proportion of shared polymorphisms, and eight haplotypes in common over distances as great as 6000 km. Only one of 16 shared polymorphisms led to an amino acid difference, and there was no compelling evidence for nonneutral variation. Parsimony networks constructed of haplotypes from both species revealed no correspondence of haplotype with either geography or taxonomy. This trend of low intraspecific genetic divergence is consistent with evidence from allozyme and microsatellite data and is interpreted in terms of both extensive gene flow and recent range expansion from relatively large, stable populations. We argue that retention of ancestral polymorphisms is a plausible but insufficient explanation for low interspecific genetic divergence, and that extensive hybridization is a contributing factor.

Progression of stunting and its predictors among school-aged children in western Kenya.

OBJECTIVE: The objectives of this study were (1) to assess whether a cohort of school-aged children experiences progression of stunting over a 2-y-period of observation and (2) to identify baseline nutritional and body composition risk factors for the progression of stunting. METHODS: As part of a large-scale, randomized controlled trial assessing the impact of insecticide-treated bednets (ITNs) on nutritional status, we longitudinally followed a cohort of school-aged children over a 2-y-period in western Kenya. Anthropometric measurements were made at four time points from which Z-scores for height-for-age (HAZ), weight-for-age (WAZ), and body mass index (BMIZ) were calculated. Two measures of body composition, upper arm fat area and upper arm muscle area, were derived from mid-upper arm circumference (MUAC) and triceps skinfold thickness. RESULTS: Subjects experienced a mean change in HAZ from baseline to 9 months of -0.16 [-0.19, -0.13], from baseline to 16 months of -0.18 [-0.22, -0.15], and from baseline to 24 months of -0.36 [-0.41, -0.31]. Thus, the average individual's change in HAZ at the three follow-up time points is significantly less than zero, meaning that, on average, the cohort is deviating further from NCHS reference medians over time. The baseline nutritional measure that explained the greatest amount of variance in the progression of stunting was the upper arm muscle area Z-score (F=8.1; P=0.005). CONCLUSIONS: This longitudinal study provides further evidence from a distinct ecological setting regarding the progression of undernutrition during middle childhood in the developing world. It suggests that school-aged children in the developing world do not experience catch-up growth or remain stable. Rather, they continue to deviate from NCHS standards, accruing greater height deficits with age. In addition, absolute lean body mass explained the most variability in the progression of stunting, which supports cross-sectional findings from other studies.

Microgeographic genetic differentiation of Anopheles gambiae mosquitoes from Asembo Bay, western Kenya: a comparison with Kilifi in coastal Kenya.

Microgeographic differentiation in Anopheles gambiae from seven villages less than 10 km apart in Asembo Bay, western Kenya was estimated by analysis of variability in seven microsatellite loci. Results from the Asembo Bay villages were compared with specimens collected in Kilifi, coastal Kenya, 700 km to the east. Allele frequency distribution was very similar in all villages in Asembo Bay, but differed for the Kilifi population. Genetic differentiation among villages was low with loci-specific Fst falling within the range of 0.0000-0.0085. These low estimates of differentiation correspond to among-village migration indices greater than 5.66, suggesting a high level of gene flow within the Asembo population. The Nm value between Kilifi and Asembo Bay was 1.54, indicating much lower levels of gene flow. Average observed heterozygosity among the seven villages was in all but one case less than the expected heterozygosity, most likely indicating the presence of null alleles, but possibly the presence of randomly mating units (demes) smaller than the village. We conclude that there is likely no genetic structure at the level of the village in Asembo Bay but that gene flow is restricted between western and coastal Kenya, probably by the high elevation rift.

A geographic information system applied to a malaria field study in western Kenya.

This paper describes use of the global positioning system (GPS) in differential mode (DGPS) to obtain highly accurate longitudes, latitudes, and altitudes of 1,169 houses, 15 schools, 40 churches, four health care centers, 48 major mosquito breeding sites, 10 borehole wells, seven shopping areas, major roads, streams, the shore of Lake Victoria, and other geographic features of interest associated with a longitudinal study of malaria in 15 villages in western Kenya. The area mapped encompassed approximately 70 km2 and included 42.0 km of roads, 54.3 km of streams, and 15.0 km of lake shore. Location data were entered into a geographic information system for map production and linkage with various databases for spatial analyses. Spatial analyses using parasitologic and entomologic data are presented as examples. Background information on DGPS is presented along with estimates of effort and expense to produce the map information.

PIP: The global positioning satellite (GPS) network system is comprised of 24 satellites orbiting at an altitude of about 10,900 miles. The authors describe how a simple modification of GPS known as differential GPS (DGPS) can be used to produce a highly accurate base map in a tropical area. DGPS circumvents the effects of selective availability (SA) error, an intentional error component added for security purposes at each satellite, to yield a highly accurate position fix. This paper documents the use of DGPS to obtain highly accurate longitudes, latitudes, and altitudes of 1169 houses, 15 schools, 40 churches, 4 health care centers, 48 major mosquito breeding sites, 10 borehole wells, 7 shopping areas, major roads, streams, the shore of Lake Victoria, and other geographic features of interest associated with a longitudinal study of malaria in 15 villages in western Kenya. 70 sq. km were mapped, including 42.0 km of roads, 54.3 km of streams, and 15.0 km of lake shore. Location data were entered into a geographic information system for map production and linkage with various databases for spatial analyses. Spatial analyses using parasitologic and entomologic data are presented as examples. Less than $25,000 was spent upon this project, of which $15,000 was for hardware and software.

Transmission of epidemic Vibrio cholerae O1 in rural western Kenya associated with drinking water from Lake Victoria: an environmental reservoir for cholera?

Sub-Saharan Africa has the highest reported cholera incidence and mortality rates in the world. In 1997, a cholera epidemic occurred in western Kenya. Between June 1997 and March 1998, 14,275 cholera admissions to hospitals in Nyanza Province in western Kenya were reported. There were 547 deaths (case fatality rate = 4%). Of 31 Vibrio cholerae O1 isolates tested, all but one were sensitive to tetracycline. We performed a case-control study among 61 cholera patients and age-, sex-, and clinic-matched controls. Multivariate analysis showed that risk factors for cholera were drinking water from Lake Victoria or from a stream, sharing food with a person with watery diarrhea, and attending funeral feasts. Compared with other diarrheal pathogens, cholera was more common among persons living in a village bordering Lake Victoria. Cholera has become an important public health concern in western Kenya, and may become an endemic pathogen in the region.

Effect of Plasmodium falciparum parasitemia density on hemoglobin concentrations among full-term, normal birth weight children in western Kenya, IV. The Asembo Bay Cohort Project.

The relative importance of acute high-density versus persistent low-density Plasmodium falciparum parasitemia in contributing to the public health problem of malarial anemia remains unclear. The Asembo Bay Cohort Project in western Kenya collected monthly hemoglobin (Hb) and parasitologic measurements and biweekly assessments of antimalarial drug use among 942 singleton live births between 1992 and 1996. A mixed-model analysis appropriate for repeated measures data was used to study how time-varying parasitemia and antimalarial drug exposures influenced mean Hb profiles. Incidence of World Health Organization-defined severe malarial anemia was 28.1 per 1,000 person-years. Among children aged less than 24 months, concurrent parasitemia was significantly associated with lower mean Hb, especially when compared to children with no concurrent parasitemia. Increased densities of the 90-day history of parasitemia preceding Hb measurement was more strongly associated with mean Hb levels than concurrent parasitemia density. While the highest quartile of 90-day parasitemia history was associated with lowest mean Hb levels, children in the lowest 90-day exposure quartile still experienced significantly lower Hb levels when compared to children who remained parasitemia-free for the same 90-day period. The results highlight the importance of collecting and analyzing longitudinal Hb and parasitologic data when studying the natural history of malarial anemia.

A longitudinal investigation of IgG and IgM antibody responses to the merozoite surface protein-1 19-kiloDalton domain of Plasmodium falciparum in pregnant women and infants: associations with febrile illness, parasitemia, and anemia.

This study was aimed at delineating characteristics of naturally acquired immunity against the merozoite surface antigen-1 (MSP-1) of Plasmodium falciparum, a candidate malaria vaccine antigen. A case/control study was performed on 75 case/control pairs of infants with febrile illness at the time of the first detected infection indicating a clinical case. The presence and level of antibodies at one month prior to the first infection and at the time of the first infection in the afebrile group was significantly higher than in the febrile group. Decreased parasite density and decreased infection-related loss of hemoglobin was seen in infants with anti-MSP-1(19kD) IgG antibodies. In addition, mothers who were positive for the presence of these antibodies conferred protection against placental infection and infection in their infants. In this study, development of anti-MSP-1(19kD) antibody responses in 24 infants were studied longitudinally using monthly serum samples collected from birth until approximately one year of age. In addition, umbilical cord blood sera and respective mothers' sera were analyzed. Longitudinal studies of antibody responses revealed several short-lived IgG and IgM peaks throughout an infant's first year that correlated with detection of parasitemia. The protection against parasitemia and febrile illness was observed in infants when anti-MSP-1(19kD) antibodies were present; when infants were negative for IgG, they had a 10-times greater risk of becoming parasitemic. These data from a longitudinal and prospective study of malaria suggest a protective role for anti-MSP-1(19kD) antibodies in infants and pregnant women.

All-cause mortality among young children in western Kenya. VI: the Asembo Bay Cohort Project.

Although all-cause mortality has been used as an indicator of the health status of childhood populations, such data are sparse for most rural areas of sub-Saharan Africa, particularly community-based estimates of infant mortality rates. The longitudinal follow-up of more than 1,500 children enrolled at birth into the Asembo Bay Cohort Project (ABCP) in western Kenya between 1992 and 1996 has provided a fixed birth cohort for estimating all-cause mortality over the first 5 yr of life. We surveyed mothers and guardians of cohort children in early 1999 to determine survival status. A total of 1,260 households were surveyed to determine the survival status of 1,556 live births (99.2% of original cohort, n = 1,570). Most mothers (66%) still resided but 27.5% had migrated, and 5.5% had died. In early 1999, the overall cumulative incidence of all-cause mortality for the entire 1992-1996 birth cohort was 26.5% (95% confidence interval, 24.1-28.9%). Neonatal and infant mortality were 32 and 176 per 1,000 live births, respectively. These community-based estimates of mortality in the ABCP area are substantially higher than for Kenya overall (nationally, infant mortality is 75 per 1,000 live births). The results provide a baseline description of all-cause mortality among children in an area with intense Plasmodium falciparum transmission and will be useful in future efforts to monitor changes in death rates attributable to control programs for specific diseases (e.g., malaria and HIV/AIDS) in Africa.

Longitudinal cohort study of the epidemiology of malaria infections in an area of intense malaria transmission I. Description of study site, general methodology, and study population.

A large-scale longitudinal cohort project was initiated in western Kenya in June 1992. The primary purpose of the project was to study Plasmodium falciparum malaria in a highly endemic area using a comprehensive and multidisciplinary approach, which included epidemiology, entomology, and immunology. Between June 1992 and July 1994, pregnant women living in 15 rural villages were identified during a monthly census and 1,164 were enrolled. The women were followed-up throughout their pregnancy and they, along with their newborn infants and direct siblings of the infants' less than 15 years of age, were monitored over time. As of May 1995, 1,017 infants had been born to these women. This paper presents the design and general methodology used in this study and describes the initial experience with intense monitoring of a large population over a prolonged period.

Longitudinal cohort study of the epidemiology of malaria infections in an area of intense malaria transmission II. Descriptive epidemiology of malaria infection and disease among children.

A large-scale longitudinal cohort project was initiated in western Kenya in June 1992. Between June 1992 and July 1994, 1,848 children less than 15 years of age were monitored prospectively for a mean of 236 days. During this period, 12,035 blood smears were examined for malaria and only 34% were found to be negative. Parasite prevalence (all species) decreased with age (from a high of 83% among children 1-4 years old to 60% among children 10-14 years old). Even more dramatic decreases were noted in the prevalence of high density falciparum infection (from 37% among children 12-23 months old to < 1% among 10-14-year-old children) and in clinical malaria (20% to 0.3% in the same age groups). Children < 1 year of age accounted for 55% of all cases of anemia detected. Anemia was consistently associated with high density infection in children < 10 years of age (20% to 210% increased risk relative to aparasitemic children). These results demonstrate the relationship between high-density malaria infection and two clinical manifestations of malarial illness.

Analysis of repeated hemoglobin measures in full-term, normal birth weight Kenyan children between birth and four years of age. III. The Asemobo Bay Cohort Project.

Anemia is an important public health problem. During very early childhood numerous factors affect hemoglobin (Hb) concentration over time, making single cross-sectional measurements difficult to interpret when studying the natural history of anemia or evaluating anemia control strategies. We analyzed repeated Hb measures contributed by 942 Kenyan children between birth and 48 months of life using a mixed effects model, with a regression spline used to describe the population mean Hb profile, and random intercepts and slopes and first-order autoregressive correlation structure to accommodate the within-individual correlation among the repeated Hb measures. The approach facilitates the study of time-stationary and time-varying covariates that influence Hb in early life. The fitted mean Hb profile obtained from the analytic model is consistent with the observed mean Hb of the study population. Village of residence was associated with greatest difference in mean Hb at time of birth (16 versus 19 g/dL; P < 0.0001). Monthly weight-for-age was also associated with mean Hb after 3 months of age. This is the first description of an analysis strategy specifically for repeated Hb measures collected in a longitudinal field study in Africa. The strategy will facilitate improved study of time-varying covariates thought to influence pediatric anemia.