bluuebunny/crossref_metadata_2025 huggingface dataset:
The Role of Rhizobial Biodiversity in Legume Crop Productivity in the West Asian Highlands. III.Rhizobium meliloti
Authors: Materon L. A. , Keatinge J. D. H. , Beck D. P. , Yurtsever N. , Karuc K. , Altuntas S.
Published: October 2008

The native rhizobia capable of symbiosis with potential pasture legume crops for the west Asian highlands were surveyed and estimates made of the numbers and nitrogen fixing efficiency of isolates ofRhizobium melilotiwith a range of annualMedicagospecies. Soils were collected from 105 sites at elevations between 500 and 2200 m. Numbers of bacteria were generally adequate to permit efficient nodulation but the nitrogen fixing efficiency of three of the four host species with the indigenous rhizobia was often low. In contrast, nitrogen fixation inM. aculeatawas generally highly efficient. No overall geographic pattern in either numbers or efficiency of nitrogen fixation was evident. Substantial further research is required before annual medic crops can be successfully introduced into highland crop/livestock systems in Turkey and elsewhere in the west Asian highlands.

Biodiversidad en elRhizobium meliloti
The Role of Rhizobial Biodiversity in Legume Crop Productivity in the West Asian Highlands. IV. Rhizobium ciceri
Authors: Keatinge J. D. H. , Beck D. P. , Materon L. A. , Yurtsever N. , Karuc K. , Altuntas S.
Published: October 2008

The native rhizobia capable of symbiosis with chickpea crops in the Turkish highlands were surveyed and estimates made of the numbers of bacteria and the nitrogen fixing efficiency of isolates of R. ciceri in symbiosis with an improved Turkish cultivar and a local landracc. Soils were collected from locations at elevations between 500 and 2200 m.

Native rhizobia specific to the local landrace were more abundant than those specific to the improved cultivar but nitrogen fixation efficiencies of all isolates were consistently poor. Agronomic research priorities must include the identification of strains of rhizobia symbiotically efficient and ecologically persistent in highland soils. Comprehensive trials with these strains as artificial inoculants on chickpeas are required throughout the region.

Biodiversidad en el Rhizobium ciceri
Experiments with Maize in Trinidad
Authors: Gibbon D. P.
Published: October 2008

The results are recorded of three field experiments, designed to investigate the effects of plant population and nitrogen fertilizer on growth and yield of maize. High yields of grain can be obtained in Trinidad provided plant populations are at least 20 000 plants per acre, nitrogenous fertilizer is added at the rate of 5–6 cwt per acre, weed and insect pests are controlled, and water is not a limiting factor at any stage of crop growth. Growth analysis has shown the importance of high leaf area indices in the production of high grain yields.
Repeatability of Milk Yield and Birth Weights of Goats in Malaya
Authors: Mahmud Anuwar Bin , Devendra C.
Published: October 2008

Repeatability estimates of milk yield and length of lactation of local, ½ Anglo-Nubian × local and ¾ Anglo-Nubian × local cross-bred goats were calculated. There were highly significant differences in the effect of dams on milk yields for the third, fourth and fifth lactations for local goats, when considered together. No significant differences were found for the first two lactations. For the ½ Anglo-Nubian cross-bred goats significant differences were also found for the first and second lactations, but not for the third lactation. No significant differences were found for the two lactations in the case of the ¾ Anglo-Nubian cross-bred goats. The effect of lactation periods were not significant for the three types of goats. The mean repeatability estimates for local goats were 0·47, 0·42 for ½ Anglo-Nubian and 0·54 for ¾ Anglo-Nubian cross-bred goats, which were comparable to those reported for cattle. The between-dam effect was highly significant when three lengths of lactations were combined in local goats, and the interval between lactations were also significant, but these two effects were not significant for the ½ Anglo-Nubian and ¾ Anglo-Nubian cross-bred goats. The estimates of repeatability for length of lactation averaged 0·29 for local goats, 0·17 for ½ Anglo-Nubian and 0·53 for ¾ Anglo-Nubian cross-bred goats. The correlation coefficients between milk yield and length of lactation were positive and statistically significant for all the three types of goats, ranging from 0·59 to 0·93. The similarity of the genetics of goats to those of cattle and sheep is mentioned.
Effect of Depth of Tillage on Yield of Upland Paddy and on Associated Weeds
Authors: Pande H. K. , Bhan V. M.
Published: October 2008

Four depth of tillage treatments were given by ploughing to 7 cm. depth by bullock-drawn plough and 14, 21 and 28 cm. depth with a tractor-drawn mouldboard plough in 1962–63. A significant decrease in bulk density was observed with the 21 and 28 cm. ploughing, negatively correlated with dry matter of crop roots and yield of grain. The effectiveness of 28 cm. tillage in reducing the population and dry matter of weeds was significant when compared to tillage at 7 and 14 cm. and there were significant relations between dry matter of weeds and yield of grain. Crop roots under tractor tillage were significantly greater than with 7 cm. tillage. Grain yield was maximum under 28 cm. tillage followed by 21, 14 and 7 cm. deep tillage in that order. The higher grain yields were associated with a greater number of fertile tillers per metre of row and higher yields per tiller.
ADOPTION DYNAMICS OF TITHONIA DIVERSIFOLIA FOR SOIL FERTILITY MANAGEMENT IN PILOT VILLAGES OF WESTERN KENYA
Authors: KIPTOT EVELYNE
Published: October 2008

This paper presents the results of a study that was undertaken to assess adoption dynamics of Tithonia diversifolia in Siaya and Vihiga districts of western Kenya from 1997 to 2004. The study was undertaken among a random sample of 120 farmers from eight pilot villages exposed to the technology. Descriptive statistics and a logit regression model were used to analyse data. The findings show that more farmers in pilot villages of Siaya are taking up the use of Tithonia than in Vihiga. As of 2004, 52% of farmers in Siaya were adopters compared to only 8% in Vihiga. Results of the logit regression model show that the use of Tithonia biomass for soil fertility management (SFM) is more likely to be adopted in a context where there is a scarcity of animal manure, farmers are willing to plant it on farms and hire casual labour. The use of Tithonia by smallholder farmers for SFM is therefore a promising low-cost option that can be scaled up to areas where farmers face similar constraints.
NEMATODE COMMUNITY STRUCTURE UNDER COMPOST AND CHEMICAL FERTILIZER MANAGEMENT PRACTICE, IN THE NORTH CHINA PLAIN
Authors: HU CHENG , CAO ZHI-PING
Published: October 2008

A long-term field experiment was conducted at the Qu-Zhou experimental station, China Agricultural University to study how the nematode community structure was influenced by compost and chemical fertilizer, using no amendment as the control. Soil samples were collected from 0–10 cm and 10–20 cm depths. The different treatments led to a significant difference in the total number of nematodes, bacterivores, plant parasites, omnivores-predators and nematode richness. The total number of nematodes, bacterivores, omnivores-predators and nematode richness were found to decrease in chemical fertilizer-treated plots. Although plant parasites were more abundant under compost treatment than under chemical fertilization, the relative abundance of plant parasites in the compost-treated plots was smaller. The application of chemical fertilizer decreased the number of genera of bacterivores and omnivores-predators. The numbers of total nematodes, bacterivores, plant parasites and omnivores-predators were significantly positively correlated with the contents of total organic carbon, total N, alkali-hydrolysable N, available P and available K. The compost-treated plots tended to have a greater diversity of nematodes than chemical fertilizer treated plots, so there was a healthy soil ecosystem under compost treatment.
COMPETITIVE ABILITY OF WINTER CEREAL–COMMON VETCH INTERCROPS AGAINST STERILE OAT
Authors: VASILAKOGLOU I. , DHIMA K. , LITHOURGIDIS A. , ELEFTHEROHORINOS I.
Published: October 2008

Intercropping cereals with legumes for forage or food production is extensively used as a cropping practice in many parts of the world. A 2-year field study was conducted using common vetch (Vicia sativa), winter wheat (Triticum aestivum), triticale (× Triticosecale), barley (Hordeum vulgare) and oat (Avena sativa) sole crops as well as common vetch intercrops with each of these cereals in a 35:65 cereal:common vetch ratio based on seed numbers, to determine their ability to compete with sterile oat (Avena sterilis spp. sterilis). At nine weeks after planting, fewer sterile oat plants emerged in common vetch sole crop than in cereal sole crops. Intercropping of cereals with common vetch generally did not affect sterile oat stem number and biomass compared with cereal sole crops. At harvest, cereal sole crops provided greater total dry biomass (DB) than the common vetch sole crop. However, triticale and oat produced more DB than winter wheat and barley. In most cases intercropping reduced total DB compared with cereal sole crops. The results of this study indicated that intercropping of the four winter cereals with common vetch did not provide any significant competitive advantage against sterile oat. However, common vetch sole crop showed the greatest suppressive ability against sterile oat among the sole crops or intercrops studied.
INTEGRATED NUTRIENT MANAGEMENT OF PEARL MILLET IN THE SAHEL COMBINING CATTLE MANURE, CROP RESIDUE AND MINERAL FERTILIZER
Authors: AKPONIKPE PIERRE B. I. , MICHELS KARLHEINZ , BIELDERS CHARLES L.
Published: October 2008

In the Sahelian zone of Niger, there is a need to develop guidelines for integrated nutrient management, which relies on the potential nutrient sources of manure, pearl millet residue and mineral fertilizers. A fully factorial on-station experiment was conducted during the 1994 and 1995 rainy seasons at Sadoré, Niger, combining application of: (i) broadcast millet residue (300, 900 and 2700 kg ha−1), (ii) broadcast cattle manure (300, 900 and 2700 kg ha−1) and (iii) mineral fertilizer (unfertilized control, 15 kg N ha−1 + 4.4 kg P ha−1 and 45 kg N ha−1 + 13.1 kg P ha−1). Manure and fertilizer increased millet yields in both years whereas residue was effective in 1995 only. The effect of manure and residue were additive, as was the effect of manure and fertilizer but only up to 50 kg N ha−1. However in 1995, the response to fertilizer was approximately doubled in the presence of 900 or 2700 kg residue ha−1 compared to fertilizer with 300 kg ha−1 residue, indicating a strong synergistic effect. This synergistic effect was reflected in the partial factor productivity of nitrogen and phosphorous in both years. Two treatment combinations stand out as particularly relevant based on yield, partial factor productivity and nutrient balance criteria: 2700 kg manure ha−1 combined with (i) 300 kg residue and no fertilizer (95% grain yield increase); (ii) 900 kg residue ha−1 and 15 kg N + 4 kg P ha−1 (132% grain yield increase). There is a need for similar, long-term experiments to confirm the present results.
MODELLING CROP–LIVESTOCK SYSTEMS FOR ACHIEVING FOOD SECURITY AND INCREASING PRODUCTION EFFICIENCIES IN THE ETHIOPIAN HIGHLANDS
Authors: AMEDE TILAHUN , DELVE ROBERT J.
Published: October 2008

An action research process was conducted with communities in Gununo, southern Ethiopia (2000–2003), to develop alternative cropping strategies for achieving their food security and cash needs. Farmers identified three major production objectives depending on their household priorities and socio-economic status. In Group I, farmers are currently food insecure and want to produce enough food from their own farms. In Group II, they produce enough food but want to fulfil their financial needs. In Group III, farmers rely on off-farm activities and want to increase cash income. The current system mostly fulfils the nutritional requirement of Group II. Groups I and III were highly food deficit from their own farms, with production covering less than seven months per year and fulfilling <50% of the recommended daily allowances (RDA) for human nutrition. Using a linear programming optimization model, it was possible to fulfil the RDA of Group I by reallocating the cropping area of maize, sweet potato, coffee and wheat to potato, enset and kale in proportions of 50, 29 and 15%, respectively. To satisfy both financial and nutritional needs of Group II, an increase in the proportion of coffee and beans by about 29 and 7.3%, respectively, over the current land allocation was needed. This shift would triple their cash income. The cash income of Group III increased four-fold by full replacement of the cereals and root crops by coffee (48%) and teff (52%), though the total income was not enough to secure food security due to their small landholdings. In farms of Groups I and II, the shift to the suggested cropping will reduce soil erosion by about 40%, while it will have no effect on farms of Group III. This shift will reduce the quantity and quality of livestock feed, except for Group I. Moreover, it will increase the farm crop water requirement 17.5 and 37% in Groups I and III (resource poor households) and reduce it in resource rich households of Group II. These changes did not imply extra labour in any groups. Whilst this model can optimize systems for food security and cash income, its research for development value is in identifying possible intensification strategies for farming systems and their implications on the farming systems, rather than generating practical recommendations for all cropping systems.
EFFECTS OF GRAFTING ON TEA 2. DROUGHT TOLERANCE
Authors: TUWEI G. , KAPTICH F. K. K. , LANGAT M. C. , SMITH B. G. , CORLEY R. H. V.
Published: October 2008

The drought tolerance of tea clones in Kenya can be improved by grafting onto appropriate rootstocks, with more susceptible clones showing greater improvement. It appears that drought may have distinct effects on rootstock and scion, with rootstock performance correlated with xylem water potential, while scion performance was correlated with stomatal conductance. Drought tolerance is not the only requirement for a rootstock under Kenyan conditions, however, and the most tolerant rootstocks do not necessarily give the greatest overall yield increase when non-drought years are included.
Rates of microfilarial production by Onchocerca volvulus are not cumulatively reduced by multiple ivermectin treatments
Authors: BOTTOMLEY CHRISTIAN , ISHAM VALERIE , COLLINS RICHARD C. , BASÁÑEZ MARIA-GLORIA
Published: October 2008

Regular distribution of ivermectin reduces onchocerciasis transmission and morbidity by killing, within humans, the microfilarial stage of the parasite (microfilaricidal effect). In addition, ivermectin exerts a so-called embryostatic effect by which microfilarial production by the adult female worm becomes suppressed during a number of weeks after treatment. To assess the overall effect of ivermectin on onchocerciasis transmission and evaluate the likelihood of local elimination of the infection it is important to estimate the magnitude of the anti-fertility effect over the course of a treatment programme. Estimates of the effect of repeated drug treatments on the production of microfilariae by adult Onchocerca volvulus were obtained by developing a model that was fitted to data collected from three hyperendemic communities in Guatemala, where eligible residents received ivermectin twice per year for two and a half years. The data consist of microfilarial load measurements in the skin, collected just before each six-monthly treatment during the programme. The model that is developed describes the dynamics of an individual host's expected microfilarial load over the 30-month study period. We adopt a Bayesian approach and use Markov chain Monte Carlo (McMC) techniques to fit the model to the data. Combining estimates from the three villages, average microfilarial production in the first six months post-treatment was reduced by ~64% of its pre-treatment level, regardless of values chosen for the pre-ivermectin fertility rate within plausible ranges. Increased adult worm death rate after treatment (to mimic removal of macrofilariae via nodulectomy during the programme) resulted in a smaller estimated magnitude of the embryostatic effect (rate of microfilarial production was reduced by ~58% of pre-ivermectin value). After subsequent treatments, the rate of microfilarial production appeared to be similarly decreased. The data and analyses therefore do not support the hypothesis of a cumulative effect of multiple ivermectin treatments on microfilarial production by female worms.
Transmission electron microscopy analysis of the interfaces of TiAlN/Mo multilayers
Authors: Tavares C.J. , Rebouta L. , Rivière J.P. , Denanot M.F.
Published: October 2008

This paper focus on the analysis of the interfaces of nanocomposite TiAlN/Mo multilayers by high-resolution transmission electron microscopy (HRTEM). These thin films were deposited by reactive magnetron sputtering, with modulation periods below 7 nm. The structural disorder at the interfaces was probed by the analysis of the X-ray diffraction data, and afterwards correlated with the TEM observations on the cross-sections of the TiAlN/Mo multilayers. For specific deposition conditions, these structures can be prepared with relatively planar interfaces, revealing layer-by-layer growth. For modulation periods below 3 nm the intermixing acts a major role in the degradation of the multilayer chemical modulation.
Nonstoichiometry Effects in SrTiO3 Ceramics Assessed by Transmission Electron Microscopy
Authors: Amaral L. , Senos A.M.R. , Vilarinho P.M.
Published: October 2008

Strontium titanate (SrTiO3, ST) has a perovskite type structure that is cubic at room temperature, but transforms into a tetragonal one at 105K. At very low temperatures, ST exhibits an extremely large dielectric permittivity and piezoelectric and superconducting characteristics. ST finds applications in tunable microwave devices, due to a dependence of its dielectric response on the electric field and low microwave losses. ST electrical properties are strongly dependent on grain boundaries features and directly influenced by grain size distribution. It was found in our previous studies that a small variation in the stoichiometry of ST has a significant effect on the grain size of the sintered ceramic and related electrical properties: increased grain size and dielectric permittivity values have been reported for Ti excess compositions whereas Sr excess caused a decrease of grain size and of the dielectric permittivity. The tailoring of the dielectric properties by small non-stoichiometric variations in ST needs, however, a full understanding of its effects on the microstructure, phases structure and on the structure / composition of the grain boundaries.
Structure and Microstructure of Y-doped Strontium Titanate Ceramics
Authors: Tkach Alexander , Vilarinho Paula M. , Reaney Ian M.
Published: October 2008

High dielectric constant important for functional electronic applications have been reported in the Sr1-1.5xYxTiO3 ceramic system with a maximum value for x = 0.01 coincident with the maximum grain size. This observation points to a possible correlation between the dielectric response and the microstructure of these ceramics. A solid solubility limit around x = 0.04 was reported recently by Fu et al., although the second phase was observed by X-ray diffraction only for x = 0.07. Therefore, the structure, microstructure and local composition of Sr1-1.5xYxTiO3 ceramics (x = 0 − 0.05) prepared by conventional mixed oxide method is investigated in this work by transmission electron microscopy (TEM) and scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy facilities.
The Valance Determination of Cerium Ions in α-SiAlON by Electron Energy Loss Spectroscopy Analysis
Authors: Yurdakul H. , Turan S.
Published: October 2008

SiAlON ceramics have found applications in many different areas due to their excellent engineering properties such as high hardness, fracture toughness, good thermal shock and oxidation resistance. SiAlON exist mainly in two different polymorphs: a (MxSi12-(m+n)Al(m+n)OnN16-n; M: metal and rare earth cations, x≈0,35 and n≤1,35) and β (β-Si6-zAlzOzN8-z; 0≤z≤4). In general, stable alpha and beta phases separately as well as in combination of α and β are obtained by incorporation of metal and rare earth cations as sintering additives. The metal cations such as Li, Mg, Ca, Y, and most lanthanide cations with the exception of La, Ce, Pr and Eu are able to stabilise α-SiAlON structure. Ekstrom et al. 1991 found that cerium can not occupy interstitial sites in α-SiAlON structure due to the fact that ionic radius of Ce3+ (0.103 nm) is too large, whereas ionic radius of Ce4+ (0.080 nm) is too small to stabilise α-SiAlON structure. After this work, several studies carried out to incorporate cerium cations into α-SiAlON structure. It was shown that cerium cation alone can be incorporated into α-SiAlON if the samples are either fast cooled after sintering, or when the samples are spark plasma sintered. On the other hand, cerium can also be incorporated into the α-SiAlON structure when it is used as a sintering additive together with a smaller α-SiAlON stabiliser cation such as Yb or Ca. Similar results were observed in other multi-cation doped SiAlONS that non α-SiAlON stabiliser cations like Sr2+ (0.112 nm) and La3+ (0.106 nm) are able to stabilise α-SiAlON when used together with α-SiAlON stabiliser cations such as Ca or Yb. Although it was shown that cerium existed in mixed valance state at domain boundaries in Ce-doped and spark plasma sintered α-SiAlON, there is no work on the valance determination of cerium in sintered α-SiAlON which has no domain boundaries. Therefore, in this study; it was aimed to incorporate cerium into α-SiAlON structure by combining with Yb3+ and the determination of possible cerium valence states (Ce3+/Ce4+) in both α-SiAlON grains and secondary phases.
In Vitro Bioactivity of PMMA-co-EHA Composites Filled with SiO2-Free Glass
Authors: Lopes P.P. , Ferreira B.J.M. Leite , Correia R.N. , Fernandes H.F.V.
Published: October 2008

Bioactive materials for potential medical application have inspired and stimulated new searches. It has been confirmed that bioactive glasses bond to living bone through an apatite layer that precipitates on their surface in physiological media. These glasses normally constituted by silica, where the silicon is the network former, induce apatite nucleation by the formation of Si-OH groups. The presence of OH groups seems to be of utmost importance in the bioactive behaviour of materials. It was revealed that even metals, such as pure titania gel can bond to bone, if previously subjected to alkali and heat treatments. In the present work a new composite with a Ca-P-Ti glass was synthesized and its in vitro bioactivity was studied in Kokubo's simulated body fluid. It is believed that the formation of Ti-OH groups on the glass can induce apatite precipitation on the composites surface.
Microscopic Characterization of the Thermal Evolution of Stainless Steel Coatings Sputter-deposited onto WC Particles
Authors: Fernandes C.M. , Senos A.M.R. , Vieira M.T.
Published: October 2008

The hardmetal composites are generally produced from powders of tungsten carbide (WC) and of metal elements, belonging to group 8-10 of the periodic table, which are mixed together by wet milling. News processes, alternatives to milling, have been developed, aiming a higher uniformity of the metallic binder distribution in WC based composites, together with other technological benefits. One of those methods consists of the sputter deposition of metal binder onto the WC powder leading to powder particles coated with the metallic elements. The particles coating showed to be chemically and morphologically very uniform and possesses a nanocrystalline structure and improved surface properties, such as powder's flowability, pressing behaviour, sinterability and thermal reactivity.
Effect of Temperature in the Evolution of Ni/Al Nanolayers
Authors: Ramos A.S. , Simões S. , Calinas Rosa , Viana F.
Published: October 2008

Nickel aluminides can be formed by thermal annealing of alternate layers of Ni and Al that react exothermically. These metals have medium/high energy of mixing and when in adiabatic conditions the reaction could become self-propagating. The first phase to form in Ni/Al reactions has been widely investigated, but there is no consensus regarding this subject. Depending on the overall chemical composition and modulation period of the multilayer, and on the processing history, the first phase to form could be NiAl3, NiAl and Ni2Al9.
Reinforcement Coating on Stainless Steel and Copper Powders
Authors: Castanho J.M. , Matos M. , Vieira M.T.
Published: October 2008

The continuous miniaturization of the mechanical components and devices push to microfabrication techniques such as μPIM (micro-Powder Injection Moulding) and laser sintering, particularly DMLS (Direct Metal Laser Sintering).
Structural and Microanalytical Studies of CrO2 Thin Films on c-Sapphire by High Resolution Electron Microscopy Methods
Authors: Ortiz M.I. , Sousa P.M. , Ballesteros C. , Silvestre A.J. , Cohen L.F. , Conde O.
Published: October 2008

Chromium dioxide (CrO2) has been extensively used in the magnetic recording industry. However, it is its ferromagnetic half-metallic nature that has more recently attracted much attention, primarily for the development of spintronic devices. CrO2 is the only stoichiometric binary oxide theoretically predicted to be fully spin polarized at the Fermi level. It presents a Curie temperature of ∼ 396 K, i.e. well above room temperature, and a magnetic moment of 2 mB per formula unit. However an antiferromagnetic native insulating layer of Cr2O3 is always present on the CrO2 surface which enhances the CrO2 magnetoresistance and might be used as a barrier in magnetic tunnel junctions.
TEM and SEM in-situ annealing of nanocrystalline copper thin films
Authors: Simões S. , Calinas R. , Ferreira P.J. , Viana F. , Vieira M.T. , Vieira M.F.
Published: October 2008

Materials mechanical resistance is known to depend on the size of structural features, accordingly to the familiar HallPetch equation. For the nanometer range of grain sizes, this relationship breaks down and a change of the grain size exponent is needed to satisfy this dependency. Nevertheless, the superior strength of the nanocrystalline material relays on the small dimension of its grains. Characterization of the thermal stability of these materials becomes relevant since a large fraction of atoms are in the grain boundaries and, as a result, its structure posses a large excess of energy that promotes grain growth. Grain growth in nanocrystalline metals has been observed well below the temperatures needed to promote grain growth in coarse grained materials; in some cases, even at room temperature. From this perspective, the study of grain growth in nanocrystalline metals is crucial for the development of new nanocrystalline materials with outstanding mechanical properties. There are many studies that propose models to explain the mechanism of nucleation and growth of annealing twins in F.C.C. materials. In-situ TEM and SEM techniques are invaluable for understanding and characterizing dynamic microstructural changes like nucleation and growth of grains and twins. This is an important observation because twinning affects the properties of materials and so is essential to comprehend the mechanism of twin formation. Other advantage of the in-situ TEM technique is the study of grain growth in ultra fine film with a thickness in the range of 50 to 100 nm. With these techniques, the mechanisms and kinetics of grain growth in nanocrystalline thin films can be observed and studied in real time.
The importance of SEM-EDS analysis in the study of old mortars
Authors: Adriano P. , Silva A. Santos , Veiga M.R. , Mirão J. , Candeias A.E
Published: October 2008

The study of old mortars composition, using physical-chemical, mineralogical and microstructural characterization has an important role in the preservation of architectural heritage, allowing a deep knowledge about the materials used, construction techniques, possible repairs and degradation processes.
Porogen Effect of Bioactive Glass on Poly(L-lactide) Scaffolds: Evidences by Electron Microscopy
Authors: Barroca N.B. , Daniel-da-Silva A.L. , Fernandes M.H.V. , Vilarinho P.M.
Published: October 2008

Recently, porous polymer-ceramic composites have been developed and represent promising scaffolds to be used as synthetic extracellular matrix in bone tissue engineering since they combine the advantages of these two types of materials. On the other hand bioactive glasses (BG) have been used as ceramic fillers to promote bioactivity and to enhance mechanical properties and osteoblast functions. Among all the requirements, these 3D porous structures should have a controllable average pore size larger than 100 μm as well as good pore interconnectivity to allow vascularization and tissue ingrowth. The goal of this study is to investigate the effect of the addition of a bioactive glass on the porous structure development of the scaffolds prepared by thermally induced phase-separation and also to test the bioactivity of these composite scaffolds. Poly (L-lactic) acid (PLLA) was chosen as the polymer matrix because of its well-known biocompatibility and adjustable physical and mechanical properties. Micron-sized (<10 μm) glass from the 3CaO.P2O5-MgO-SiO2 system was produced in our laboratory and used as the bioactive ceramic filler.
Modification of Polyimide Wettability by KrF Pulsed Laser Ablation
Authors: Oliveira V. , Vilar R.
Published: October 2008

Laser ablation has been extensively studied in polymers because of their considerable utility in diverse fields such as medicine, microelectronics, photonics, etc. As a result, laser ablation of polymers has generated considerable interest in research during the past two decades. Among the many aspects of laser ablation of polymers, several authors have reported the formation and growth of conical structures during laser processing with UV laser radiation. Although this aspect of laser ablation has been investigated since the 1980s, only a few applications of these structures have been reported. In the present paper, we study the development of conical structures on polyimide treated with KrF laser radiation as a function of the radiation fluence, and its effect on the wettability of the polymer.
Morphological and structural characterization of oxidized La-Si sputtered thin films
Authors: Oliveira J.C. , Cavaleiro A.
Published: October 2008

High temperatures in Solid Oxide Fuel Cells (SOFCs) place stringent requirements on the cell components materials which result in high material costs for interconnects and insulation and cause the degradation of the system. The development of Intermediate Temperature SOFCs (IT-SOFCs) will require electrolyte materials with higher ionic conductivity at moderate temperatures than the conventional yttria-stabilised zirconia (YSZ). Recently, lanthanum silicates with an apatite-like structure (La9,33Si6O26) have attracted considerable interest as potential materials for low cost electrolyte. Some of these materials show conductivities at 875 K comparable to, or better than, YSZ; their high level of oxide ion mobility was related to the presence of oxygen channels along the c axis which facilitate the diffusion of the anionic species (O2− for SOFCs applications). Another way to fulfil IT-SOFCs requirements is to decrease the electrolyte thickness to the micrometer range and, therefore, the ohmic drop at the electrolyte. Magnetron sputtering has already been used to synthesize thin film electrolytes for SOFCs owing to its versatility for depositing complex materials as well as its ability to control their composition and morphology. The manufacturing of thin film lanthanum silicate electrolytes by magnetron sputtering, with thicknesses in the micrometer range, can be achieved through the previous deposition of La-Si films and subsequent thermal oxidation. The present study focuses on the characterization of the morphological and structural changes upon oxidation of La-Si films deposited by magnetron sputtering.
Characterization of Sputtered Shape Memory Alloy Ni-Ti Films by Cross-sectional TEM and SEM
Authors: Martins R.M.S. , Mücklich A. , Schell N. , Silva R.J.C. , Mahesh K.K. , Fernandes F.M. Braz
Published: October 2008

Ni-Ti Shape Memory Alloys (SMAs) have been attracting attention as smart materials because they can work as sensors and actuators at the same time. Miniaturization of mechanical devices is evolving toward sub-micron dimensions raising important questions in the properties of Ni-Ti films. In thin films it is essential to investigate the microstructure to understand the origin of the thickness limit. The design of functionally graded films has also been considered but for their successful development it is important to characterize the variations in crystalline structure.
Ultrastructural Characterization of Corpus Cavernosum of Ageing, Orchidectomy and Diabetes Rat Experimental Models
Authors: Cordeiro A.L. , Figueiredo A. , Godinho F. , Martins I. , Vendeira P. , Almeida H. , Neves D.
Published: October 2008

Small vessels of the penis are very sensitive to structural and functional changes, and small disturbances can conduce to any degree of erectile dysfunction (ED). For this motive, ED is now considered as an early manifestation of atherosclerosis and consequently a precursor of systemic vascular disease. Ageing, diabetes and hipogonadic states are recognized risk factors for ED, contributing together to vascular damage of penile tissue. Penile trabeculae of corpus cavernosum in the rat, constituted by connective tissue with abundant collagen fibrils, scarce fibroblasts and fibroelastic components, support smooth muscle fibers in subendothelium location. Corpus cavernosum structural elements act in concert, allowing increase of intra-cavernous arterial flow and smooth muscle relaxing, processes which are fundamental to penis erection. The purpose of this study is to clarify ultrastructural organization of corpus cavernosum of experimental rat models of known ED-risk factors.
ACTH Induces ERK 1/2 Activation in Rat Adrenal Primary Cultures
Authors: Rodrigues A.R. , Gouveia A.M. , Ferreira J.G. , Almeida H.
Published: October 2008

Adrenocorticotropic hormone (ACTH) is the most potent stimulator of adrenal cortex, acting through the Melanocortin-2 receptor (MC2R). ACTH induces secretion of steroid hormones, critical for the normal stress response and plays also an important role on cell proliferation and differentiation. MC2R is a classical G-Protein coupled receptor (GPCR), thus activating Protein Kinase A (PKA). However, many studies suggested a cross-talk between different signalling pathways and a more complex intracellular network. In fact, in adrenocortical Y1 tumour cell line, ACTH may activate Extracellular Regulated Kinases 1/2 (ERK 1/2), which belong to the Mitogen-Activated Protein Kinases (MAPKs) family. In addition, this pathway was implicated in in vivo proliferation and steroidogenesis as shown by our group. In order to further explore and clarify ACTH signalling mechanisms, we made the present work to establish a model of primary cultures of rat adrenal cells.
Stereological Analysis of Mitochondria and Smooth Endoplasmic Reticulum Distribution in Human Oocytes at Prophase I
Authors: Luís A. , Rocha E. , Oliveira E , Silva J. , Barros A. , Sousa M.
Published: October 2008

The structure of human oocytes at the different maturation stages is known based on descriptive studies of its ultrastructural composition. The tridimensional quantitative ultrastructural analysis of human oocytes would be important for understanding folliculogenesis and establishing adequate methods of in vitro oocyte maturation. In this study, stereological methods were applied to quantify the distribution of mitochondria (M) and smooth endoplasmic reticulum (SER) in oocytes at the germinal vesicle (VG) stage of prophase I.
From Mad Cows to Neurotic Yeast: Novel Molecular Approaches to Understand Neurodegeneration
Authors: Outeiro T.F.
Published: October 2008

Aging is the major known risk factor for Alzheimer's disease (AD) and Parkinson's disease (PD), but genetic deffects have been associated with familial cases. Huntington's disease (HD) is a purely genetic neurodegenerative disorder, where mutations in the IT15 gene, encoding for the protein huntingtin, determine the development of the disease. The Prion diseases differ from these other disorders because they can also have infections origin.
Leaf Morphoanatomy in Hakea sericeae and H. salicifolia
Authors: Teixeira G. , Monteiro A. , Pepo C.
Published: October 2008

Hakea sericeae Schrader and H. salicifolia (Vent.) B. L. Burtt. are perennials, which belong to the Proteaceae family. Native to dry tropical zones from South Australia, they became aggressive species, particulary in damaged, dried and windy areas and are now considered invaders in some places of mainland Portugal. With no natural predators, the use of chemical control is the main way to manage these plants but they both show a small foliar area, therefore usually little success has been achieved.
Detection of MMP-9, MMP-1 and TIMP-1 in the Lung of Developing Mouse after Prenatal Administration of Vitamin A
Authors: Pinto Maria de Lurdes , Rodrigues Paula , Coelho Ana , Gonçalves Carlos , Bairos Vasco
Published: October 2008

Matrix metalloproteinases (MMPs) are a family of proteolytic enzymes that together with their tissue inhibitors (TIMPs) are important modulators of normal lung development and harmful mediators of lung damage. Several studies support the role for an imbalance of MMPs and TIMPs homeostasis in the pathogenesis of paediatric lung failure. It was verified that MMP-9 and MMP-9/TIMP-1 ratio increases in the broncho-alveolar lavage of patients with bronchopulmonary dyspasia (BPD). Maternal administration of vitamin A, once the period of retinoid-induced teratogenesis is over, results in an enhancement of lung foetal organogenesis, an increase in the lung's elastic fibres, and an increase in VEGF pulmonary and plasma levels.
Lung elastic fibres from embryonic to adult birds
Authors: Honório Ana , Pinto Maria de Lurdes , Gonçalves Carlos , Bairos Vasco
Published: October 2008

In mammals it is well known the role of the elastic fibres in the lung development and its fundamental importance in the process of distending and recoil of the organ as a whole. The bird's lungs are compact and virtually non-expansible.

After morphological studies on elastic fibres distribution and quantification by image analysis we carried out a study on biochemical methods to quantify elastin in the avian lung, using domestic fowl (Gallus gallus) as an experimental model. We made use of two analytical methods for the elastin determination in these animal lungs from the 14th day of hatching until the 42nd day after hatchling.
Management of vesicouretral using immunohistochemistry
Authors: Ferraz-Gameiro Pedro , Fritsch Helga , Oswald Josef
Published: October 2008

The vesicouretral reflux is an important pathology that has an incidence of about 1% in children, and may be associated with renal scarring and hypertension due to kidney failure. The reason for this insufficient ureterovesical valve is based on congenital dysplasia, atrophy and architectural derangement of smooth muscle fibers of the distal ureteral muscle wall. The ureterovesical junction is a way of avoiding the reflux from the bladder to the higher urinary system (ureters and kidneys). This junction has a valve-like action. One important factor on the prevention of the reflux is the length of the intravesical ureter. These conditions (ureterovesical junction and length of the intravesical ureter) are, respectively, an active and a passive way of preventing reflux.
Characterization of Mycobacterium bovis Phagosome
Authors: Jordao L. , Simoes M. , Bleck C. , Griffiths G. , Anes E.
Published: October 2008

Mycobacterium tuberculosis complex are among the most successful pathogens. Their success resides in the ability to interfere with intracellular traffic avoiding natural pathways of the phagosome maturation. Recently, mycobacteria escape from the phagosome to the cytosol was investigated as an alternative survival strategy. In this context we decided to determine the exact intracellular location of Mycobacterium bovis in different host macrophages and characterize the pathogen intracellular niche for survival. The main goal here was to characterize live vs dead M. bovis spp phagosome in different host macrophages. Macrophages infection, fluorescence and EM procedures were carried out as described previously.
Colocalization Analysis of PPP1 Isoforms and Two Novel Targeting Subunits in Breast Carcinoma
Authors: Sousa C. , Vintém A.P. , Fardilha M. , Silva O. da Cruz e , Silva E. da Cruz e
Published: October 2008

Protein phosphatase 1 (PPP1) is the PPP most ubiquitous and each isoform interact with regulatory subunits that may be responsible for their subcellular localization. We identified PPP1R15B, C1ORF71 as novel regulators and the aim of this study was their further characterization in carcinoma cells. We analysed localization of each regulator in MDA-MB-468 cells and we transfected with constructs that we made with each as a GFP-fusion protein. For PPP1 cellular localization we used specific antibodies for each isoform. We observed the cells under a fluorescent microscope and LSM and we quantified co-localization. We found a high overlap coefficient of both the novel proteins with PPP1alpha and PPP1gamma1. We propose a model in which PPP1 regulator interacts with one or two regulatory subunits that may be used as target for therapeutic strategies.
Adaptation of Ranaviruses from Peneda-Gerês National Park (Portugal) to Cell Cultures and their Characterization
Authors: de Matos A.P. Alves , Caeiro M.F. , Marschang R.E. , Papp T. , Soares C. , Marçal M.R. , Carretero M.A.
Published: October 2008

Ranaviruses are known to produce iseases in fish, amphibians and reptiles, being involved in high mortality episodes in aquaculture farms and in the decline of amphibian populations worldwide. Mass mortality episodes were previously detected in Triturus marmoratus from two lagoons of the Peneda-Gerês National Park (PGNP) (NW Portugal). Ranavirus-like particles were identified in tissues of diseased newts T. marmoratus and T. boscai. Here we report on the molecular and ultrastructural characterization of these viruses.
Subcellular Localization of a Novel Alternative Splicing of IIIG9 and Colocalization with PPP1gamma Isoforms
Authors: Sousa C. , Vintém A.P. , Fardilha M. , Silva O. da Cruz e , Silva E. da Cruz e
Published: October 2008

In testis we find mainly PPP1gamma2 isoform. We hypothesize that in different cell types we can find different regulatory subunits that may constitute targets for therapeutics of diseases such as male infertility, cancer and Alzheimer's disease. We identified a novel alternative splicing isoform of IIIG9 in testis, a known regulator of PPP1, IIIG9sT, and the aim of this study was its further characterization. We used a specific antibody for IIIG9sT in order to characterize its localization in bovine sperm cells. We also transfected IIIG9sT-GFP construct in mouse spermatogonia cells (GC-1 cells) and we used specific antibodies for each PPP1 isoform for the colocalization studies. We observed them under a fluorescent microscope and a LSM and quantified a high co-localization with PPP1gamma1 and 2 isoforms.
Quercus suber Infected by Phytophthora cinnamomi. Effects at Cellular Level of Cinnamomin on Roots, Stem and Leaves
Authors: Maia I. , Medeira C. , Melo E. , Cravador A.
Published: October 2008

Phytophthora cinnamomi has been reported to be regularly associated with cork and holm oak decline. This oomycete secretes elicitins, a group of unique highly conserved proteins that can enhance plant defence reactions.
THE “HARD FORM” OF SCULPTURE: MARBLE, MATTER AND SPIRIT IN EUROPEAN SCULPTURE FROM THE ENLIGHTENMENT THROUGH ROMANTICISM
Authors: WALSH LINDA
Published: October 2008

The apparently distinct aesthetic values of naturalism (a fidelity to external appearance) and neoclassicism (with its focus on idealization and intangible essence) came together in creative tension and fusion in much late eighteenth-century and early nineteenth-century sculptural theory and practice. The hybrid styles that resulted suited the requirements of the European sculpture-buying public. Both aesthetics, however, created difficulties for the German Idealists who represented a particularly uncompromising strain of Romantic theory. In their view, naturalism was too closely bound to the observable, familiar world, while neoclassicism was too wedded to notions of clearly defined forms. This article explores sculptural practice and theory at this time as a site of complex debates around the medium's potential for specific concrete representation in a context of competing Romantic visions (ethereal, social and commercial) of modernity.
LITERARY PRACTICES AND THE SOCIAL LIFE OF TEXTS
Authors: AUGST THOMAS
Published: October 2008

Throughout the twentieth century, as literary texts circulated through high-school and college classrooms, reading became a specialized skill. Especially with the dominance of the “new criticism” in the 1930s, literature acquired an autonomous life as “text,” demanding intensive “close reading” of its verbal complexity and formal coherence as an aesthetic object. Beginning in the 1970s, with the proliferation of programs devoted to African-American culture, gender studies, sexuality studies, and ethnic studies programs, the literary canon became more diverse. In the mid-1980s new historicism helped push aesthetic formalism further from the agenda of literary education in the university, promoting new interest in historical contexts even as psychoanalytic, deconstructive, and reader-response approaches continued to fetishize “textuality” as their primary object of inquiry. Whatever the vagaries of theory, method, and subdisciplinary turf battles through which scholars have wandered over the last few decades, we have remained in our professional practices of reading and teaching committed to a hermeneutics of interpretation. Even as scholars developed arguments about history or culture, the teaching and criticism of literature has continued to rely on the institutional and psychological isolation of reading, as an individual exercise in mastery of the text fostered by silence and solitude.
Organic molecules in the spectral line survey of Orion KL with the Odin Satellite from 486–492 GHz and 541–577 GHz
Authors: Koning N. , Kwok S. , Bernath P. , Hjalmarson Å. , Olofsson H.
Published: October 2008

A spectral line survey of Orion KL has been performed over the frequency range of 486–492 GHz and 541–577 GHz using the Odin satellite. Over 1000 lines have been identified from 40 different molecular species, including several organic compounds such as methyl cyanide (CH3CN), methanol (CH3OH, 13CH3OH), and dimethyl ether (CH3OCH3).