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Physicochemical properties of diets are believed to play a major role in the regulation of digesta transit in the gastrointestinal tract. Starch, being the dominant nutrient in pig diets, strongly influences these properties. We studied transport of digesta solids and liquids through the upper gastrointestinal tract of ninety pigs in a 3 × 3 factorial arrangement. Dietary treatments varied in starch source (barley, maize and high-amylose maize) and form (isolated starch, ground cereal and extruded cereal). Mean retention times (MRT) of digesta solids ranged 129–225 min for the stomach and 86–124 min for the small intestine (SI). The MRT of solids consistently exceeded that of liquids in the stomach, but not in the SI. Solid digesta of pigs fed extruded cereals remained 29–75 min shorter in the stomach compared with pigs fed ground cereals (P < 0·001). Shear stress of whole digesta positively correlated with solid digesta MRT in the stomach (r 0·33, P < 0·001), but not in the SI. The saturation ratio (SR), the actual amount of water in stomach digesta as a fraction of the theoretical maximum held by the digesta matrix, explained more variation in digesta MRT than shear stress. The predictability of SR was hampered by the accumulation of large particles in the stomach. In addition, the water-holding capacity of gelatinised starch leads to a decreased SR of diets, but not of stomach digesta, which was caused by gastric hydrolysis of starch. Both of these phenomena hinder the predictability of gastric retention times based on feed properties.
The Hkakabo Razi region located in northern Myanmar is an Important Bird Area and part of the Eastern Himalayan Biodiversity Hotspot. Within the framework of the World Heritage Convention to enlist the site under criterion (ix) and (x), we conducted a biodiversity assessment for passerine birds using DNA barcoding and other molecular markers. Of the 441 bird species recorded, we chose 16 target species for a comparative phylogeographic study. Genetic analysis was performed for a larger number of species and helped identifying misidentified species. We found phylogeographic structure in all but one of the 16 study species. In 13 species, populations from northern Myanmar were genetically distinctive and local mitochondrial lineages differed from those found in adjacent regions by 3.9–9.9% uncorrected genetic distances (cytochrome-b). Since the genetic distinctiveness of study populations will be corroborated by further differences in morphology and song as in other South-East Asian passerines, many of them will be candidates for taxonomic splits, or in case an older taxon name is not available, for the scientific description of new taxa. Considering the short time frame of our study we predict that a great part of undetected faunal diversity in the Hkakabo Razi region will be discovered.
This study aimed to examine in vivo starch digestion kinetics and to unravel the mechanisms of starch hydrolysing enzymes. Ninety pigs (23 (sd 2·1) kg body weight) were assigned to one of nine treatments in a 3×3 factorial arrangement, with starch source (barley, maize, high-amylose (HA) maize) and form (isolated, within cereal matrix, extruded) as factors. We determined starch digestion coefficients (DC), starch breakdown products and digesta retention times in four small-intestinal segments (SI1–4). Starch digestion in SI2 of pigs fed barley and maize, exceeded starch digestion of pigs fed HA maize by 0·20–0·33 DC units (P<0·01). In SI3–4, barley starch were completely digested, whereas the cereal matrix of maize hampered digestion and generated 16 % resistant starch in the small intestine (P<0·001). Extrusion increased the DC of maize and HA maize starch throughout the small intestine but not that of barley (P<0·05). Up to 25 % of starch residuals in the proximal small intestine of pigs was present as glucose and soluble α(1–4) maltodextrins. The high abundance of glucose, maltose and maltotriose in the proximal small intestine indicates activity of brush-border enzymes in the intestinal lumen, which is exceeded by α-amylase activity. Furthermore, we found that in vivo starch digestion exceeded our in vitro predictions for rapidly digested starch, which indicates that the role of the stomach on starch digestion is currently underestimated. Consequently, in vivo glucose release of slowly digestible starch is less gradual than expected, which challenges the prediction quality of the in vitro assay.
This prospective study involved a longitudinal analysis of the progression of hearing thresholds in patients with osteogenesis imperfecta.
Audiometric results from 36 osteogenesis imperfecta patients (age range, 6–79 years) were compared between two test times with an average interval of 4 years. Audiometric evaluation included acoustic admittance measurements, acoustic stapedial reflex measurements, pure tone audiometry and otoacoustic emissions testing.
Air conduction pure tone average, corrected for sex and age, and bone conduction pure tone average increased significantly in the study population (p < 0.05 and p < 0.001, respectively). In 14.3 per cent of the evaluated ears, an alteration in type and/or severity of hearing loss was observed.
After an average time interval of four years, significant changes in hearing status occurred in a population of osteogenesis imperfecta patients. These findings highlight the importance of regular audiological follow up in osteogenesis imperfecta patients, including audiometry, and measurements of acoustic admittance, acoustic stapedial reflexes and otoacoustic emissions.
The cold, wet climate of the Arctic has led to the extraordinary preservation of archaeological sites and materials that offer important contributions to the understanding of our common cultural and ecological history. This potential, however, is quickly disappearing due to climate-related variables, including the intensification of permafrost thaw and coastal erosion, which are damaging and destroying a wide range of cultural and environmental archives around the Arctic. In providing an overview of the most important effects of climate change in this region and on archaeological sites, the authors propose the next generation of research and response strategies, and suggest how to capitalise on existing successful connections among research communities and between researchers and the public.
Background: When measuring young Duchenne Muscular Dystrophy (DMD) patients’ health-related quality of life (HRQoL), parent-proxy reports are heavily relied on. Therefore, it is imperative that the relationship between parent-proxy and child self-report HRQoL is understood. This study examined the level of agreement between children and their parent-proxy rating of the child’s HRQoL. Methods: We used FOR-DMD clinical trial baseline data. HRQoL, measured using the PedsQL inventory, was reported by 178 parent and child (ages 4 to 7 years) dyads. Intracorrelation coefficients (ICC) measured absolute agreement while paired t-tests determined differences in the average HRQoL ratings between groups. Results: The level of agreement between child and parent-proxy ratings of HRQoL was poor for the generic PedsQL scale (ICC: 0.29) and its subscales; and, similarly low for the neuromuscular disease module (ICC:0.16). On average, parents rated their child’s HRQoL as poorer than the children rated themselves in all scales except for psychosocial and school functioning. Conclusions: Child and parent-proxy HRQoL ratings are discordant in this study sample, as occurs in other chronic pediatric diseases. This should be taken into account when interpreting clinical and research HRQoL findings in this population. Future studies should examine reasons for parents’ perception of poorer HRQoL than that reported by their children.
Metazoan parasite communities of Lepomis gibbosus (Centrarchidae), one of the most successfully introduced fish species in Europe, were studied at two isolated ponds (Knielingen, Tropfen) along the Upper Rhine in Germany. Nine parasite taxa were observed, including North American species co-introduced to Europe (ancyrocephalid monogeneans, diplostomid trematodes), circumpolar species infecting L. gibbosus in both their native and non-native ranges (bothriocephalid cestodes) and locally acquired parasitic nematodes. Both parasite communities consisted predominantly of North American species. Acquisition of local parasites was not observed at Tropfen, where the fish community comprised just two species, with L. gibbosus dominant. Low prevalence and abundance of acquired parasites was found at Knielingen, which supported a diverse fish community. At Tropfen, a high abundance of the North American parasite Posthodiplostomum centrarchi probably contributed to the lower condition index, hepatomegaly and splenomegaly observed. Due to low local parasite competency, L. gibbosus appears to have no significant impact on parasite dynamics in affected habitats.
A theory for the thermal stability of hot coronal loops is presented, which is based on the resonant electrodynamic heating theory of Ionson (1982) and the evaporation/condensation scenario of Krall and Antiochos (1980). The theory predicts that gradual changes in the length of a loop or in its magnetic field strength can trigger catastrophic changes in the X-ray visibility of the loop, without the need for a change in the magnetic field topology.
A natural explanation is thereby given for the observations of X-ray brightenings in loops and loop evacuations with coronal rain.
A physical measure on the attractor of a system describes the statistical behavior of typical orbits. An example occurs in unimodal dynamics: namely, all infinitely renormalizable unimodal maps have a physical measure. For Lorenz dynamics, even in the simple case of infinitely renormalizable systems, the existence of physical measures is more delicate. In this article, we construct examples of infinitely renormalizable Lorenz maps which do not have a physical measure. A priori bounds on the geometry play a crucial role in (unimodal) dynamics. There are infinitely renormalizable Lorenz maps which do not have a priori bounds. This phenomenon is related to the position of the critical point of the consecutive renormalizations. The crucial technical ingredient used to obtain these examples without a physical measure is the control of the position of these critical points.
The loss of estrogen during menopause causes changes in the female body, with wide-ranging effects on health. Estrogen-containing hormone replacement therapy (HRT) leads to a relief of typical menopausal symptoms, benefits bone and muscle health, and is associated with tissue-specific gene expression profiles. As gene expression is controlled by epigenetic factors (including DNA methylation), many of which are environmentally sensitive, it is plausible that at least part of the HRT-associated gene expression is due to changes in DNA methylation profile. We investigated genome-wide DNA methylation and gene expression patterns of white blood cells (WBCs) and their associations with body composition, including muscle and bone measures of monozygotic (MZ) female twin pairs discordant for HRT. We identified 7,855 nominally significant differentially methylated regions (DMRs) associated with 4,044 genes. Of the genes with DMRs, five (ACBA1, CCL5, FASLG, PPP2R2B, and UHRF1) were also differentially expressed. All have been previously associated with HRT or estrogenic regulation, but not with HRT-associated DNA methylation. All five genes were associated with bone mineral content (BMC), and ABCA1, FASLG, and UHRF1 were also associated with body adiposity. Our study is the first to show that HRT associates with genome-wide DNA methylation alterations in WBCs. Moreover, we show that five differentially expressed genes with DMRs associate with clinical measures, including body fat percentage, lean body mass, bone mass, and blood lipids. Our results indicate that at least part of the known beneficial HRT effects on body composition and bone mass may be regulated by DNA methylation associated alterations in gene expression in circulating WBCs.
This study evaluates attitudes toward production of three major types of biomass—corncobs, corn stover, and dedicated energy grass—using responses to a mail survey of 2,250 Iowa farmers. We examine how factors influencing willingness to supply biomass vary across biomass types and analyze the presence of potential correlations across interest in growing various types of biomass. We find that correlation in choices across biomass types is strong and statistically significant. Farmers consider corn stover and corncobs as complementary, but dedicated energy grasses and corncobs or stover as substitutes. Factors affecting farmer choices also vary significantly by type of biomass.
We investigated a mixed outbreak of Legionnaires' disease (LD) and Pontiac fever (PF) at a military base to identify the outbreak's environmental source as well as known legionellosis risk factors. Base workers with possible legionellosis were interviewed and, if consenting, underwent testing for legionellosis. A retrospective cohort study collected information on occupants of the buildings closest to the outbreak source. We identified 29 confirmed and probable LD and 38 PF cases. All cases were exposed to airborne pathogens from a cooling tower. Occupants of the building closest to the cooling tower were 6·9 [95% confidence interval (CI) 2·2–22·0] and 5·5 (95% CI 2·1–14·5) times more likely to develop LD and PF, respectively, than occupants of the next closest building. Thorough preventive measures and aggressive responses to outbreaks, including searching for PF cases in mixed legionellosis outbreaks, are essential for legionellosis control.
Vestibular nerve section is a highly effective procedure for the control of vertigo in patients with Ménière's disease. However, hearing loss is a possible complication. If hearing loss occurs after vestibular nerve section, magnetic resonance imaging should make it possible to establish the presence or absence of an intact cochlear nerve.
Case report and review of the world literature concerning cochlear implantation after vestibular nerve section.
We present a patient who developed subtotal hearing loss after vestibular nerve section. Magnetic resonance imaging was used to verify the presence of an intact cochlear nerve, enabling successful cochlear implantation.
To our knowledge, this is the first reported case of cochlear implantation carried out after selective vestibular nerve section. Given recent advances in cochlear implantation, this case indicates that it is essential to make every effort to spare the cochlear nerve if vestibular nerve section is required. If hearing loss occurs after vestibular nerve section, magnetic resonance imaging should be undertaken to establish whether the cochlear nerve is intact.
LiCoO2 and LiNiO2, two important cathode materials for Li-ion batteries, were studied in their respective bulk and thin-film form. X-ray absorption spectroscopy (XAS) has been used to probe the local atomic structure and structural defects in the thin-film and bulk cathodes. Results comparing Li(Co,Ni)O2 in the bulk and thin-film forms suggests a correlation between intrinsic stress and local strain in the thin-film. This local strain is manifested by a collapse of the six-fold rotational symmetry within the metal-metal layer of the Li(Co,Ni)O2 system into a two fold one. The relationship between annealing conditions and the resulting local strain in these films is examined.
Extreme macronutrient intakes possibly lead to different brain signalling. The aim of the present study was to determine the effects of ingesting high-protein v. high-carbohydrate food on liking and wanting task-related brain signalling (TRS) and subsequent macronutrient intake. A total of thirty female subjects (21·6 (sd 2·2) years, BMI 25·0 (sd 3·7) kg/m2) completed four functional MRI scans: two fasted and two satiated on two different days. During the scans, subjects rated all food items for liking and wanting, thereby choosing the subsequent meal. The results show that high-protein (PROT) v. high-carbohydrate (CARB) conditions were generated using protein or carbohydrate drinks at the first meal. Energy intake and hunger were recorded. PROT (protein: 53·7 (sd 2·1) percentage of energy (En%); carbohydrate: 6·4 (sd 1·3) En%) and CARB conditions (protein: 11·8 (sd 0·6) En%; carbohydrate: 70·0 (sd 2·4) En%) were achieved during the first meal, while the second meals were not different between the conditions. Hunger, energy intake, and behavioural liking and wanting ratings were decreased after the first meal (P< 0·001). Comparing the first with the second meal, the macronutrient content changed: carbohydrate − 26·9 En% in the CARB condition, protein − 37·8 En% in the PROT condition. After the first meal in the CARB condition, wanting TRS was increased in the hypothalamus. After the first meal in the PROT condition, liking TRS was decreased in the putamen (P< 0·05). The change in energy intake from the first to the second meal was inversely related to the change in liking TRS in the striatum and hypothalamus in the CARB condition and positively related in the PROT condition (P< 0·05). In conclusion, wanting and liking TRS were affected differentially with a change in carbohydrate or protein intake, underscoring subsequent energy intake and shift in macronutrient composition.
In this paper, a clear view on the bulk microstructure of MDMO-PPV:PCBM blends as used in bulk hetero-junction organic solar cells is obtained by means of TEM (Transmission Electron Microscopy). Using TEM, 3-dimensional information is acquired on phase separated regions, formed during casting. Particle statistics illustrate quantitatively that a.o. drying conditions and choice of solvent dramatically influence the blend structure. More information about the lateral blend structure and distribution is obtained in cross-sectional view. Since blend morphology is strongly related to photovoltaic performance, TEM can be a powerful tool for understanding today's photovoltaic performances and screening new sets of materials.
High mobility channel materials and new device structures will be needed to meet the power and performance specifications in future technology nodes. Therefore, the use of Ge and III/V materials and novel devices such as heterojunction TunnelFET’s is investigated for future CMOS applications. High-performance CMOS can be obtained by combining Ge pMOS devices with nMOS devices made on III/V compounds such as InGaAs. In all cases the key challenge is the electrical passivation of the interface between the high-k dielectric and the alternative channel materials.
Recent studies have demonstrated good electrical properties of the GeO2/Ge interface. Since the GeO2 layer is very hygroscopic, full in-situ processing of GeO2 formation and high-k deposition must be performed or other methods must be employed to stabilize the GeO2 layer. One of the most successful passivation techniques for Ge MOS gate stacks is a thin, epitaxial layer of Si. A lot of attention went into better understanding of this passivation and the effects of its optimization on various device characteristics. It was found that mobility and Vt trends in both pMOS and nMOS transistors can be explained based on defects located at the Si/SiO2 interface.
Unfortunately, III-V/oxide interfaces are not quite as robust and most interfaces present rather high densities of interface states. Although, considerable improvements have been realized in the reduction of the interface state density, further developments are required to obtain high performance MOS devices. To this purpose various passivation methods were critically evaluated. Simulations using Density Functional Theory reveal the possibility of using a thin amorphous layer made of GeOX to obtain an electrically unpinned gap. The major challenge resides in the control of the c-Ge thickness and the oxidation of this layer to avoid the diffusion of oxygen atoms at the Ge/GaAs(001) interface. Promising results are obtained by optimizing the surface preparation, high-k deposition and annealing cycle on In0.53Ga0.47As-Al2O3 interfaces. Self-aligned inversion channel n-MOSFETs fabricated on p-type In0.53Ga0.47As demonstrate inversion-mode operation with high drive current and a peak electron mobility of 3000 cm2/Vs.
Since ultimately the major showstopper on the scaling roadmap is not device speed, but rather power density, the introduction of these advanced materials will have to go together with the introduction of new device concepts. Novel structures such as heterojunction TunnelFET’s can fully exploit the properties of these new materials and provide superior performance at lower power consumption by virtue of their improved subthreshold behaviour. Vertical surround gate devices produced from nanowires allow the introduction of a wide range of materials on Si. This illustrates the possibilities that are created by the combination of new materials and devices to allow scaling of nanoelectronics beyond the Si roadmap.
Nanoporous organosilicate films have been recently prepared using tetraalkylammonium cations in acid and basic media, outperforming other materials. Resulting films using basic medium were called zeolite-inspired low-k dielectrics. Here we study the dependence of the properties of these films on the used silica sources: methyltrimethoxy silane (MTMS) and tetraethyl orthosilicate (TEOS). A set of experiments varying the MTMS:TEOS ratio were prepared in acid medium and characterized. A textural, physico-chemical, mechanical, and electrical characterization of this series of experiments is presented.