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Understanding how differences in animal husbandry practices affect the reproducibility of research results is critical. We sought to understand how different beddings might influence dietary obesity studies. We compared the effects of paper and corncob bedding on weight gain, metabolism, and gut microbiome (GM) of mice fed a high-fat diet (HFD) or a normal diet (ND) and evaluated effects on fecal and cecal microbiomes collected from these cohorts after euthanasia. Male C57BL/6J mice at 5 wk age were allowed to acclimate to the facility and the assigned bedding for one week before being placed on HFD or remaining on the ND for 12 wk. Fecal pellets and cecal samples were collected and frozen for batched 16S sequencing. Mice had similar body weight, visceral gonadal white adipose tissue (GWAT), subcutaneous inguinal white adipose tissue (IWAT), liver and spleen weights and metabolic changes regardless of the bedding type. Baseline microbiota differences were detected one week after bedding assignment. After 12 wk, the GM showed significant differences depending on both bedding and diet. The effects of the bedding were not significantly different between endpoint fecal and cecal GM, despite the inherent differences in microbiota in fecal and cecal samples. A correlation was detected between diet and the relative abundance of Bacteroidetes and Verrucomicrobia: Akkermansia. In conclusion, this study demonstrates the importance of considering bedding type when performing dietary experiments.

A number of manufacturing challenges exist in creating a robust permanent-magnet synchronous motor (PMSM) design to meet critical requirements for cogging torque and torque ripple in specific applications. In addition, reduction of the back electromotive force (BEMF) harmonics that lead to torque ripple is also required during design. Due to manufacturing tolerances, maintaining capability with these requirements is very difficult, particularly for mass production of units. A design of experiments (DOE) that combines manufacturing tolerances with assembly process variations is proposed here to address the sensitivity of cogging torque and harmonics. The limits for the parts and the process variations are extracted from an actual production environment. The DOE is laid out according to one of the robust engineering matrices chosen from Taguchi's method. The DOE results are then utilized to set the tolerance limits for manufacturing the rotor magnets and to set the allowance for the rotor assembly process variations. The method helps to limit the cogging torque and harmonics within predefined bands, thereby producing a robust motor. This paper also investigates the capability of maintaining the tolerances of magnets for a surface-mounted PMSM. The analysis is done using a finite-element method and verified with experimental results.

The stability constant for Tc(IV)/EDTA complexes were determined using a solvent extraction technique at varying ionic strength (NaCl) and the specific ion interaction theory model allowed for calculating stability constants at zero ionic strength. The stability constants at zero ionic strength for the formation of the TcOEDTA2− and TcOHEDTA− complexes are 1020.0 ± 0.4 and 1025.3 ± 0.5, respectively. The modeled Tc(IV) solubility was calculated to be 3.9 × 10−7 M at near-neutral pH and in presence of 2.5 mM EDTA, a result found to be in good agreement with published solubility experimental data. Speciation calculations showed that TcOEDTA2− is the predominant species between pH 4 and 7.5 in presence of 0.171 mM EDTA, while TcO(OH)2 0 is predominant in basic solution. These studies show that EDTA has a very strong affinity for complexation with Tc(IV) and can increase the environmental mobility of Tc(IV).

Microbes, particularly Archaea, are well-known for their superb adaptation to extreme environments. However, amazing adaptations to extreme stresses do not only occur in microbes, but also in many multicellular organisms. Examples include tardigrades and their capability to survive freezing to near absolute zero, the Pompeii worm withstanding temperatures of up to 105°C, the Crucian carp remaining active in anoxic conditions for several months, and resurrection plants, which can survive near-complete desiccation. Here, we review some of the cryptobiotic strategies and adaptations exhibited in multicellular organisms, and point out their relevance to astrobiology.

Aerosols are the primary source of chemical elements transported by rainwater, which are removed from the atmosphere by rainout or by washout. Atmospheric aerosols (sea salt, crustal dust, and biogenic aerosols) have been found as the major sources of dissolved species in river water. Dissolved components from rainwater come from those originating from sea salt aerosols; from those originating from terrestrial aerosols (soil dust, biological emissions); and from those originating from anthropogenic sources (industry, agriculture, burning of fossil fuels, etc.). Along with the geological characterization of the watershed, meteorological parameters are critically important in evaluating rainfall effects. Keywords: rainout; washout; sea salt aerosols; terrestrial aerosols; rainwater chemistry; strontium isotope

An ancient saprolite has developed on the Palaeoproterozoic granulite, granite gneiss and amphibolite bedrock of the Vuotso–Tankavaara area of central Finnish Lapland. The present day climatic regime in Finnish Lapland lies within the northern boreal zone and so the saprolite there can be regarded as fossil. Cores of saprolite were collected from 4 sections (42 samples) and analyzed chemically and mineralogically. In the study area, progressive weathering of the rocks has been marked by gradual enrichment in Al, Fe and Ti; and depletion of Na, K and Ca. The higher concentration of Fe(III) and water and reduced Na and Ca in weathered bedrock in the 4 sections are indicative of oxidation, hydration and leaching processes involved during weathering. The primary minerals in the saprolite are plagioclase feldspar, K-feldspar, quartz, garnet (almandine) and hornblende; the common secondary minerals are kaolinite, halloysite, and vermiculite in addition to minor amounts of sericite. Intense weathering is indicated by: (1) the presence of kaolinite and halloysite in 4 sections of different bedrock types, and (2) the comparatively lower SiO2/Al2O3 (wt.%) ratio (2.30) of weathered granulites (3 sections) as compared to fresh granulite (4.33) and that of weathered amphibolite (2.68) as compared to fresh amphibolite (3.56). In general, kaolinite and halloysite have formed through the weathering of feldspars, garnet, and biotite. Vermiculite is the most probable alteration product of biotite. The formation of kaolinite and halloysite in Finnish Lapland indicates wetter and warmer climatic conditions during the time of their formation than at present. The possible time for formation of the saprolite is early Cretaceous–early Tertiary into Middle Miocene.

Vertical arrays of one-dimensional tin nanowires on silicon dioxide (SiO2)/silicon (Si) substrates have been developed as anode materials for lithium rechargeable microbatteries. The process is complementary metal-oxide-semiconductor (CMOS) compatible for fabricating on-chip microbatteries. Nanoporous anodized aluminum oxide (AAO) templates integrated on SiO2/Si substrates were employed for fabrication of tin nanowires resulting in high surface area of anodes. The microstructure of these nanowire arrays was investigated by scanning electron microscopy and X-ray diffraction. The electrochemical tests showed that the discharge capacity of about 400 mA h g−1 could be maintained after 15 cycles at the high discharge/charge rate of 4200 mA g−1. Keywords: Lithium microbattery, Anode material, Tin nanowire, Anodized aluminum oxide

This study aims at predicting Carbon monoxide (CO) emission rate as well as carboxyhaemoglobin (HbCO) levelsin Al-Ain City, United Arab Emirates (UAE). Also, several mathematical models are proposed for estimating both CO emission and HbCO levels. These models yield excellent agreements between observed and predicted data and can be easily coupled with atmospheric models. Carbon monoxide exposure from motor vehicles were measured over a 3-month period from September to December 1995 at three locations in the UAE. The study is based on a sample of 148 cars. The data revealed that the major characteristics of the cars surveyed were as follows: 69.5% of the cars were Japanese, 74.3% of the cars were 5 years old; 41% of the car was range rover or four-wheel-drive car, which indicates a higher proportion of powerful cars; 58.8% was used special fuel; 51.4% had regular maintenance for their cars and 52% of the cars had 4 cylinder engine capacity. Carboxyhaemoglobin (HbCO) levels in the UAE were predicted for 1-hour (1.720 ppm) and 8-hour (8.106 ppm) exposure times. Also, on an average driving of 80 km hr−1 per day, the CO emission rate was found to be 8.729 ppm. These findings indicate that the mean 1-hour and 8-hour Carboxyhaemoglobin (HbCO) levels do not exceed the permissible standards recommended by the WHO. Additionally, the results of stepwise multiple regression analyses revealed that the factors, such as, type of car, size of cylinder, size of car, and maintaining service of the car exerted the greatest influence on the amount and concentration of pollutant emission produced by car exhaust.

Precise isolation and resolution of scan chain defects are more critical than ever due to increased reliance on scan-based design to achieve desired test content. At the same time, its diagnosis is becoming more difficult as product design increases in complexity alongside shrinking fabrication processes. In this paper, we present a new scan chain diagnosis procedure that is centered on Load Pass Unload Fail/Load Fail Unload Pass (LPUF/LFUP) and Scan Shift Logic State Mapping (SSLSM) techniques to isolate both stuck-at and timing scan chain faults without the design overhead and defect assumptions of previously proposed methods. More importantly, this procedure is extended to analyze scan chain with multiple defects, which is becoming a more frequent occurrence as process scales down in size.

Fault Isolation / Failure Analysis (FI/FA) of increasingly complex embedded memory in microprocessors is becoming more difficult due to process scaling and presence of subtle defects. As physical failure analysis (PFA) is destructive and involves expensive and time-consuming processes, fault diagnosis needs to be as precise as possible to ensure successful physical defect sighting. This paper introduces a cache Fault Isolation methodology that focuses on exhaustive data collection to derive concrete hypothesis of physical fault location and to overcome the existing FA/FI challenges. The methodology involves a novel application of existing DFT techniques in combination with circuit analysis, pattern hacking, defect localization and PFA tools. Some of the techniques, for example pattern modification or circuit simulation, are applied repeatedly in order to obtain higher-level of isolation – from cell/logic level to transistor/gate level, and finally down to physical structure/layer level. This multi-level FI approach is the key to localize the failing area to greater precision, which had proven itself in Intel Itanium® II processor yield improvement process.

The normal microbial flora of the vagina plays an important role in preventing genital and urinary tract infections in women. Thus an accurate understanding of the composition and ecology of the ecosystem is important to understanding the aetiology of these diseases. Common wisdom is that lactobacilli dominate the normal vaginal microflora of post-pubertal women. However, this conclusion is based on methods that require cultivation of microbial populations; an approach that is known to yield a biased and incomplete assessment of microbial community structure. In this study cultivation-independent methods were used to analyse samples collected from the mid-vagina of five normal healthy Caucasian women between the ages of 28 and 44. Total microbial community DNA was isolated following resuspension of microbial cells from vaginal swabs. To identify the constituent numerically dominant populations in each community 16S rRNA gene libraries were prepared following PCR amplification using the 8f and 926r primers. From each library, the DNA sequences of approximately 200 16S rRNA clones were determined and subjected to phylogenetic analyses. The diversity and kinds of organisms that comprise the vaginal microbial community varied among women. Species ofLactobacillusappeared to dominate the communities in four of the five women. However, the community of one woman was dominated byAtopobiumsp., whereas a second woman had appreciable numbers ofMegasphaerasp.,Atopobiumsp. andLeptotrichiasp., none of which have previously been shown to be common members of the vaginal ecosystem. Of the women whose communities were dominated by lactobacilli, there were two distinct clusters, each of which consisted of a single species. One class consisted of two women with genetically divergent clones that were related toLactobacillus crispatus, whereas the second group of two women had clones ofLactobacillus inersthat were highly related to a single phylotype. These surprising results suggest that culture-independent methods can provide new insights into the diversity of bacterial species found in the human vagina, and this information could prove to be pivotal in understanding risk factors for various infectious diseases.

Carbon nanotubes (CNT) are among the candidates for atomic force microscopy probes for use in high aspect ratio critical dimension metrology (CDM). Their mechanical strength at small diameters makes them ideal probes for narrow and deep features. The synthesis of CNT has been making great progress in recent years. The use of CNT in scanning probe microscopy, however, has been limited due to a number of problems. While the CNT probes generally appear to be long lasting, the manufacture of precisely aligned CNT of defined length, diameter and number of walls poses a number of challenges. Yet, such precisely defined CNT probes seem to be required if the cantilevers are to be used for CDM. Our result demonstrate, for example, that the attachment angle of CNT with respect to the cantilever beam is crucial for their application in CDM. We report about our efforts to overcome these problems by growing well-defined CNT on standard Si cantilevers using chemical vapor deposition in combination with focused ion-beam machining techniques.

Gas-phase mixing and dispersion in a typical commercial-scale diffusion furnace was investigated using computational fluid dynamic simulations and experimentation. Five regions were defined within the furnace: (i) entrance volume, (ii) annular volume around the wafer-source stack, (iii) radial volumes between wafer-source pairs, (iv) intermediate volumes between successive wafer carriers, and (v) exit volume. The mixing characteristics within each of these volumes was quantified and appropriate mixing models were defined based on the relative amount of backmixing or gas exchange within and between these volumes. A dispersion-based approach was then used to develop a simplified model describing the transient transport of water vapor (H 2 O) during a typical hydrogen injection cycle. Model parameters were calibrated using experimental data from tracer impulse studies.