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Herein, a simple and cost-effective chemical bath deposition methodology was employed to synthesize Co-doped SnS thin films, focusing on the improvement of the optical and electrical properties of the films by modulating the Co2+ ion concentrations in the reaction solution. X-ray diffraction analysis revealed a phase transformation from amorphous to a Herzenbergite orthorhombic phase with increasing Co2+ concentration. Chemical structure analysis via X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy confirmed the incorporation of Co2+ ions, along with the presence of SnS, Sn2S3, and minor CoO phases. Optical studies demonstrated a significant bandgap widening from ~ 1.0 eV (undoped) to ~ 1.7 eV (Co-doped), making the films suitable for photovoltaic applications. Electrical characterization showed a marked decrease in resistivity from ~ 3 × 109 to 22 × 106 Ω cm. These results highlight the potential of Co-doped SnS thin films for next-generation photovoltaic devices, emphasizing the importance of doping optimization to balance performance and structural integrity. [ABSTRACT FROM AUTHOR]

In this work, we investigate the electrical conductivity of carbon nanotubes (CNTs), with a particular focus on the effects of doping. Using first-principles-based approaches, we study the electronic structure, phonon dispersion, and electron–phonon scattering to understand the finite-temperature electrical transport properties in CNTs. Our study covers both prototypical metallic and semiconducting CNTs, with special emphasis on the influence of typical defects such as vacancies and the incorporation of copper or nitrogen, such as pyridinic N, pyrrolic N, graphitic N, and oxidized N. Our theoretical study shows significant improvements in the electrical conduction properties of copper-CNT composites, especially when semiconducting CNTs are functionalized with nitrogen. Doping is found to cause significant changes in the electronic density of states near the Fermi level, which affects the electrical conductivity. Calculations show that certain types of functional groups, such as N-pyrrolic, result in more than 30-fold increase in the conductivity of semiconducting CNTs compared to Cu-incorporated CNTs alone. For metallic CNTs, the conductivity is in agreement with existing experimental data, and our prediction of significant increases in conductivity with N-pyrrolic functional group is consistent with recent experimental results, demonstrating the effectiveness of doping in modifying conductivity. Our study provides valuable insight into the electronic properties of doped CNTs and contributes to the development of ultrahigh conductivity CNT composites. [ABSTRACT FROM AUTHOR]

Simple Summary: Mexico ranked among the ten countries with the highest GHG production in 2017, reporting a contribution of 1.68% of global emissions; in this sense, it has committed to reducing GHG emissions by up to 22% by 2030 (Government of Mexico, 2015). The First National Tier 2 Inventory of methane emissions from enteric fermentation of cattle in Mexico, registering 2039.21 ± 205.5 Gg of CH4 per year. Currently, most studies on livestock and climate change in Latin America are focused on quantifying CH4 emission volumes, determining emission factors, and calculating national inventories; few studies focus on the development of mitigation strategies; many positive attributes of macroalgae have been identified concerning contributing nutrients such as protein and also in the energy metabolism of animals of livestock interest. Some in vitro studies have shown that red and brown macroalgae can reduce CH4 production by controlling the populations of methanogenic bacteria in the rumen. The impact of macroalgae species on rumen function remains largely unexplored. This present study aimed to identify the biocompounds of the three types of marine macroalgae described: Macrocystis pyrifera (Brown), Ulva spp. (Lettuce), Mazzaella spp. (Red) and their effect on species-specific modulations of the rumen microbiome. The macroalgae were characterized using GC-MS. Twelve Rambouillet lambs were randomly assigned to one of four experimental diets (n = 3 per treatment): (a) control diet (CD); (b) CD + 5 g of Red algae; (c) CD + 5 g of Brown algae; and (d) CD + 5 g of Lettuce algae. After the lambs ended their fattening phase, they donated ruminal fluid for DNA extraction and 16S rRNA gene V3 amplicon sequencing. Results: The tagged 16S rRNA amplicon sequencing and statistical analysis revealed that the dominant ruminal bacteria shared by all four sample groups belonged to phyla Firmicutes and Bacteroidota. However, the relative abundance of these bacterial groups was markedly affected by diet composition. In animals fed with macroalgae, the fibrinolytic and cellulolytic bacteria Selenomonas was found in the highest abundance. The diversity in chemical composition among macroalgae species introduces a range of bioactive compounds, particularly VOCs like anethole, beta-himachalene, and 4-ethylphenol, which demonstrate antimicrobial and fermentation-modulating properties. [ABSTRACT FROM AUTHOR]

This study aimed to assess the impact of protein supplementation and its interaction with calf sex (CS) on the performance, metabolism and physiology of pregnant beef cows. Fifty‐two multiparous Zebu beef cows carrying female (n = 22) and male (n = 30) fetuses were used. Cows were individually housed from day 100 to 200 of gestation and randomly assigned to restricted (RES, n = 26) or supplemented (SUP, n = 26) groups. The RES cows were ad libitum fed a basal diet (corn silage + sugarcane bagasse + mineral mixture), achieving 5.5% crude protein (CP), while SUP cows received the same basal diet plus a protein supplement (40% CP, at 3.5 g/kg of body weight). All cows were fed the same diet during late gestation. Differences were declared at p < 0.05. No significant interaction between maternal nutrition and calf sex was found for maternal outcomes (p ≥ 0.34). The SUP treatment increased the total dry matter (DM) intake (p ≤ 0.01) by 32% and 19% at mid‐ and late‐gestation respectively. The total tract digestibility of all diet components was improved by SUP treatment at day 200 of gestation (p ≤ 0.02), as well as the ruminal microbial CP production (p ≤ 0.01). The SUP treatment increased (p ≤ 0.03) the cows' body score condition, ribeye area, the average daily gain (ADG) of pregnant components (PREG; i.e., weight accretion of cows caused by pregnancy) and the ADG of maternal tissues (i.e., weight accretion discounting the gain related to gestation) in the mid‐gestation. The SUP cows exhibited a lower maternal ADG (p < 0.01) compared to RES cows in late pregnancy. There was a 24% additional gain (p < 0.01) in the PREG components for SUP cows during late gestation, which in turn improved the calf birthweight (p = 0.05). The uterine arterial resistance and pulsatility indexes (p ≤ 0.01) at mid‐gestation were greater for RES cows. In conclusion, protein supplementation during mid‐gestation is an effective practice for improving maternal performance, growth of the gravid uterus and the offspring's birth weight. [ABSTRACT FROM AUTHOR]

Pollen, particularly from the Ambrosia genus, plays a pivotal role in triggering allergic rhinoconjunctivitis symptoms. This review delves into the global background of Ambrosia, focusing on its origins, invasive potential, and spread to South America. The ecological niche for Ambrosia species is explored, emphasizing its stability globally but exhibiting unique and dynamic features in South America. Information on Ambrosia pollen concentration in South America is summarized, revealing varying levels across countries. The establishment of new aerobiology stations, as highlighted in the latest findings, contributes valuable data for understanding allergen risk management in the region. The health perspective addresses the rise in allergic diseases due to climate change, emphasizing the need for continuous monitoring, especially in South America. Agricultural damage inflicted by Ambrosia is discussed, emphasizing its invasive potential, high seed production, and negative impact on crops, forage quality, and livestock. The review also positions Ambrosia as a marker of climate change, discussing the effects of global warming on pollen seasons, concentrations, and allergenic characteristics. The importance of expanding aerobiology stations in South America is underscored, requiring collaborative efforts from government, scientific societies, and academic institutions. The review concludes by advocating for increased monitoring to address potential challenges posed by Ambrosia, offering a basis for tailored interventions and future research in South American regions. [ABSTRACT FROM AUTHOR]

Molten salts play an important role in various energy-related applications such as high-temperature heat transfer fluids and reaction media. However, the extreme molten salt environment causes the degradation of materials, raising safety and sustainability challenges. A fundamental understanding of material-molten salt interfacial evolution is needed. This work studies the transformation of metallic Cr in molten 50/50 mol% KCl-MgCl2 via multi-modal in situ synchrotron X-ray nano-tomography, diffraction and spectroscopy combined with density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations. Notably, in addition to the dissolution of Cr in the molten salt to form porous structures, a d-A15 Cr phase was found to gradually form as a result of the metal-salt interaction. This phase change of Cr is associated with a change in the coordination environment of Cr at the interface. DFT and AIMD simulations provide a basis for understanding the enhanced stability of d-A15 Cr vs. bcc Cr, by revealing their competitive phase thermodynamics at elevated temperatures and probing the interfacial behavior of the molten salt at relevant facets. This study provides critical insights into the morphological and chemical evolution of metal-molten salt interfaces. The combination of multimodal synchrotron analysis and atomic simulation also offers an opportunity to explore a broader range of systems critical to energy applications. [ABSTRACT FROM AUTHOR]

This study investigates the influence of chemically synthesized Al2O3 dielectric layers on the performance of both metal–insulator-metal (MIM) capacitors (FTO/Al2O3/Au) and transparent thin film transistors (TTFTs) (FTO/Al2O3/ZnO/Au). Using two distinct formulations, a detail comparison based on varying precursors concentrations and the deposition time is presented. Scanning electron microscopy shows a nanopore morphology in the Al2O3 dielectric layers. Electrical characterizations for MIM devices yielded leakage currents around 6 × 10 - 4 A ∙ cm 2 and capacitance values in the 107–77 nF/cm2 range. For TTFTs, drain current vs drain-source voltage (ID-VDS) ( ∼ 1 - 8.5 μ A ) and drain current vs gate voltage (ID-VGS) (on/off ratio 2.4 × 102) were measured with chemically synthesized ZnO. Using a zinc oxide semiconductor as the active channel, the threshold voltage (Von/off = ~ 36 V) and mobility (µ = 1.23 cm2/Vs) was obtained. The application of Al2O3 as the dielectric gate, which acts as a substrate for ZnO deposition during device fabrication, induced a ZnO dendritic-like surface morphology, influencing channel conduction and exhibiting distinctive electrical behaviors corresponding to each formulation. Beyond the demonstrated capabilities of Al2O3 in these devices, this material demonstrates advantages for highly transparent and effective low-cost device fabrication. [ABSTRACT FROM AUTHOR]

In the present work, the synthesis and characterization of silicon quantum dots (SiQDs) were carried out using a novel approach involving fresh leaf extract of Ocimum basilicum var. purpurascens (OBP) as an organic silicon-reducing agent and 3-Aminopropyltriethoxysilane (APTES) as a precursor. This method offers a promising and sustainable alternative for SiQDs production. The synthesized SiQDs demonstrated water dispersibility, making them suitable for various biotechnological applications. Additionally, an increase in the hydrodynamic diameter of the SiQDs from 1.7 to 2 nm was observed, which can have significant implications in terms of stability and functionality. A notable feature of synthesized SiQDs is their ability to absorb UV radiation. This property can be exploited in photovoltaic applications, such as silicon-based solar cells, where efficient conversion of UV radiation into electrical energy is crucial. Furthermore, a decreasing emission centered at 457 nm (2.71 eV) with chromaticity coordinates from the International Commission on Illumination 1931 (CIE1931) located in the blue region was observed. This indicates that SiQDs have a wide potential for use in high-efficiency light-emitting devices with vibrant colors. To determine the energy gap (Eg) size of the SiQDs, the Tauc method based on experimental absorbance was employed. The results revealed a decrease in Eg from 2.99 eV to 2.97 eV, which is significant in terms of tailoring the optical properties of SiQDs for specific applications. [ABSTRACT FROM AUTHOR]

El Hierro island is one of the most active islands in the Canary Islands from a volcanological point of view. This is the reason why the imaging of the internal crustal structure is of huge importance. The geophysical exploration methods employed on El Hierro Island, such as gravimetry and seismic tomography, allowed obtaining the high-resolution characterization of the crust's deep part. However, these methods did not yield significant information about the surface and the shallower part of the crust. To gain a deeper insight into the shallow geological structure of El Hierro island, we employed Ambient Noise Tomography to construct a 3D S-wave velocity model. Our investigation revealed the presence of seven significant seismic velocity anomalies, partly identified by previous studies. We identified two high-velocity anomalies located in the eastern and western parts of the island at a depth between 0 and 3 km below sea level (b.s.l.). We interpreted these anomalies as dense intrusive complexes of dikes, possibly linked to the Tanganasoga volcano and the formation of the Tinor edifice. Additionally, we observed two high-velocity anomalies in the northern and southern parts of the island at a depth between 3 and 4 km b.s.l., which we related to the accumulation of solidified igneous rocks. On the other hand, a low-velocity anomaly was observed in the Golfo valley, between 0 and 0.5 km b.s.l., and we interpreted itas megalandslide deposits. This anomaly was evidenced for the first time in the present study. Finally, two low-velocity anomalies were observed in the southern part of the island at different depths, between 0-0.5 km b.s.l. and 0-2 km b.s.l. These were interpreted as fractures generated by Quaternary volcanism along the SSE Rift. Also, one of them was evidenced for the first time in this study, corresponding to the zone of the fractures produced during the Quaternary volcanism. This study has allowed us to gain a more detailed understanding of the shallow geological structure of the island. Even if most of the anomalies had been evidenced previously, we could observe the existence of two low-velocity zones in the shallow crust that have not been observed before. [ABSTRACT FROM AUTHOR]

Our study objectives were to evaluate the effects of divergent rates of body weight (BW) gain during early gestation in beef heifers on F0 performance, metabolic and endocrine status, colostrum immunoglobulins, and subsequent F1 calf characteristics, growth performance, concentrations of hormones and metabolites, and response to vaccination. Angus-based heifers (n  = 100; BW = 369 ± 2.5 kg) were adapted to individual feeding for 14 d and bred using artificial insemination with female-sexed semen. Heifers were ranked by BW and assigned to either a basal diet targeting 0.28 kg/d gain (low [ LG ], n  = 50) or the basal diet plus an energy/protein supplement targeting 0.79 kg/d gain (moderate gain [ MG ], n  = 50) until day 84 of gestation. Dam BW and blood samples were collected at 6 time points during gestation; body composition was evaluated on days −10 and 84; and fetal measurements were taken on days 42, 63, and 84. At calving (LG, n  = 23; MG, n  = 23), dam and calf BW were recorded; and colostrum, calf body measurements, and blood samples were collected. Cow–calf pairs were managed on a common diet from calving to weaning, followed by a common postnatal development period for all F1 female offspring. Growth performance, hormone and metabolite profiles, feeding behavior, and reproductive performance were assessed from birth to prebreeding in F1 heifers. Offspring were vaccinated against respiratory disease and bovine viral diarrhea pathogens on days 62.3 ± 4.13 and 220.3 ± 4.13 postcalving. By design, MG dams were heavier (P  < 0.0001) than LG on day 84, and the BW advantage persisted until subsequent weaning of F1 calves. Concentrations of serum IGF-1 and glucose were increased throughout gestation (P  < 0.001) in MG dams, whereas concentrations of NEFA were decreased (P  < 0.001) in LG dams. Calves from MG dams were 2.14 kg heavier (P  = 0.03) and had larger chest circumference (P  = 0.04) at birth compared with LG cohorts. Heifers from MG dams continued to have greater (P  ≤ 0.03) BW gain and feed efficiency during the development period, but no differences were observed (P  ≥ 0.13) in body composition, concentrations of hormones and metabolites, feeding behavior, puberty attainment, and response to vaccination in F1 offspring. Hence, early gestation rate of gain impacted BW and concentrations of glucose and IGF-1 throughout gestation in the F0 dam, resulting in altered F1 calf BW and measurements at birth and increased gain and efficiency during the development period. [ABSTRACT FROM AUTHOR]

This study examined the impact of maternal protein supplementation during mid-gestation on offspring, considering potential sex-related effects. Forty-three pregnant purebred Tabapuã beef cows (20 female and 23 male fetuses) were collectively managed in a pasture until 100 d of gestation. From 100 to 200 d of gestation, they were randomly assigned to the restricted group [(RES) − basal diet (75% corn silage + 25% sugar cane bagasse + mineral mixture); n  = 24] or control group [(CON) – same basal diet + based-plant supplement [40% of crude protein, 3.5 g/kg of body weight (BW); n  = 19]. From 200 d of gestation until parturition, all cows were equally fed corn silage and mineral mixture. During the cow–calf phase, cows and their calves were maintained in a pasture area. After weaning, calves were individually housed and evaluated during the backgrounding (255 to 320 d), growing 1 (321 to 381 d), and growing 2 (382 to 445 d) phases. Offspring's blood samples were collected at 210 and 445 d of age. Samples of skeletal muscle tissue were collected through biopsies at 7, 30, and 445 d of age. Muscle tissue samples were subjected to reverse-transcription quantitative polymerase chain reaction analysis. Prenatal treatment and offspring's sex (when pertinent) were considered fixed effects. The significance level was set at 5%. At mid-gestation, cows supplemented with protein reached 98% and 92% of their protein and energy requirements, while nonsupplemented cows attained only 30% and 50% of these requirements, respectively. The RES offspring were lighter at birth (27 vs. 31 kg), weaning (197 vs. 214 kg), and 445 d of age (398 vs. 429 kg) (P  ≤ 0.05). The CON calves had greater (P  < 0.05) morphometric measurements overall. The CON offspring had ~26% greater muscle fiber area (P  ≤ 0.01). There was a trend (P  = 0.06) for a greater Mechanistic target of rapamycin kinase mRNA expression in the Longissimus thoracis in the CON group at 7 d of age. The Myogenic differentiation 1 expression was greater (P  = 0.02) in RES-females. Upregulation of Carnitine palmitoyltransferase 2 was observed in RES offspring at 445 d (P  = 0.04). Expression of Fatty acid binding protein 4 (P  < 0.001), Peroxisome proliferator-activated receptor gamma (P  < 0.001), and Stearoyl-Coenzyme A desaturase (P  < 0.001) was upregulated in CON-females. Therefore, protein supplementation during gestation enhances offspring growth and promotes favorable responses to lipogenesis, particularly in females. [ABSTRACT FROM AUTHOR]

Copyright of Boletín Científico Centro de Museos de Historia Natural is the property of Universidad de Caldas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Structural and phase stability of the Pd-plated Ti3(Al, Si)C2–TiC composite at elevated temperatures was analyzed by the in situ X-ray diffraction method using synchrotron radiation. Porous Ti3(Al, Si)C2–TiC composite was prepared by spark plasma sintering of preceramic paper with 90 wt % of a Ti3(Al, Si)C2 powder filler at 1000°C and 20 MPa. The sintered composite was covered with a Pd film via electroless plating. During in situ investigation, the Pd-plated composite was linearly heated from 25 to 1000°C and annealed for 1 h at a maximum temperature. Structural and phase analysis reveals a formation of new Pd2Si, PdAl, and PdCx phases. It was noted that the newly formed phases began to be formed during heating at ~750°C. Scanning electron microscopy showed that the obtained Ti3AlSiC2–TiC composite had a well-developed porous structure where some pores were filled with Pd. After high-temperature treatment, Pd could be detected at depths up to 5 μm into the Ti3AlSiC2–TiC composite. [ABSTRACT FROM AUTHOR]

Copyright of Ameghiniana is the property of Argentine Paleontological Association / Asociacion Paleontologica Argentina and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ingeniería y Competitividad is the property of Universidad del Valle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Treatment of leachate and municipal wastewater has extended worldwide using already existing wastewater treatment plants. A biological aerated filter was used to treat leachate from Mexico City's largest landfill together with synthetic wastewater. After achieving stable operation of the filter under organic surface area loading rates of 8.1, 5.3, and 3.1 gCOD/m2·d, landfill leachate was added to the wastewater in volume proportions of 1, 2, and 3%. With leachate, COD removal decreases with increasing leachate concentration. Without leachate, complete nitrification was achieved with the two lower organic surface area loading rates and 93% NH4-N removal was achieved with the highest load. NH4-N removal was 71 and 39% with 2 and 3% leachate, respectively. The oxygen uptake rates decrease with increasing leachate concentration. With 3% leachate, O2 uptake rates for endogenous respiration are higher than for substrate respiration. [ABSTRACT FROM AUTHOR]

Introduction: Atopic dermatitis (AD) is a chronic, relapsing–remitting illness. In moderate-to-severe instances, recommendations urge patient-centered systemic therapy. Existing standards lack long-term treatment success requirements. A treat-to-target methodology was proposed for systemic therapy patients that requires global improvements to prompt decisions about treatment. Methods: We conducted an observational study between May 2021 and June 2022 in three Ecuadorian patients with severe AD who were treated with dupilumab to assess the clinical evolution and behavior of the subdomains evaluated by clinimetric tools. Results: Patients A and C satisfied disease-domain response criteria to dupilumab at 12 and 24 weeks, but B did not complete the algorithm objectives. Nonetheless, patient A improved AD severity, itching, bleeding, desquamation, sleep, daily activities, mood, emotions, sexual troubles, clothing, and sports subdomains. Patient B experienced reduced symptomatology, AD aggravation, daily activities impact, and work/study impairment. Patient C improved from severe to mild desquamation, itching, exudate, lichenification, and rough/dry skin. Sleep, shame, and study subdomains improved the most. Conclusion: We provide a new operational construct for analyzing current patient-reported outcome measures (PROMs) and clinician-reported outcome measures (CROMs) based on subdomains to widen our understanding of the state of disease activity and make clinical decisions when the treat-to-target strategy is not attained. [ABSTRACT FROM AUTHOR]

Traditional heifer feeding strategies typically involve modest rates of body weight (BW) gain and include a relatively low proportion of concentrate feeds. In situations of limited forage or high feed costs, additional concentrates may be included in the diets and fed at a limited rate. High-concentrate diets can enhance the efficiency of nutrient utilization, alter characteristics of the gastrointestinal tract (GIT), and influence the composition of gain. The objective of this study was to evaluate the strategy of limit-feeding highconcentrate diets on feeding behavior, carcass characteristics, and GIT morphometrics in replacement beef heifers. Crossbred beef heifers (n = 20) began receiving either a high forage (75% forage:25% concentrate; HF, n =10) or high concentrate (25% forage:75% concentrate; HC, n =10) diet 74 ± 4 d before breeding. Heifers were inseminated with sexed male semen from a single bull. Individual intake and feeding behavior data were recorded using the Insentec Roughage Intake Control system, and heifers were weighed, and diet deliveries were adjusted every 2 wk to target a BW gain of 0.45 kg/d for both groups. Heifers were harvested at 180 d of gestation, where the viscera were removed, and weights of the full gastrointestinal tract, including the stomach complex, and small and large intestines were recorded. After removing digesta, weights of the empty gastrointestinal tract, rumen-reticulum, omasum, abomasum, small and large intestine, and mesenteric fat were recorded. Carcass characteristics were assessed 24 h after slaughter. Data were analyzed using the MIXED procedure of SAS, with heifer as the experimental unit. No differences were observed in final BW, average daily gain, or body condition score (P ≥ 0.18) between treatments (Table 1). Reflecting that HC heifers were limit-fed to a greater extent than HF heifers, therefore, dry matter intake, number of meals, visits to the feed bunk, time spent eating, and time per meal were less in HC heifers than in the HF group (P ≤ 0.001). In contrast, HC heifers had greater (P ≤ 0.001) eating rates of DM per minute, per visit and per meal compared with HF heifers. Though no differences were observed in back (P = 0.31) or rib fat (P = 0.37), HC heifers had greater (P = 0.04) marbling score and tended to have greater carcass weight (P = 0.06) and ribeye area (P = 0.07) as compared with HF heifers (Table 2). Greater (P < 0.001) full weights of GIT and stomach complex, empty weight of rumen-reticulum, weight of total digesta, and digesta as a proportion of BW (i.e., fill) were observed in HF heifers. In contrast, HC heifers had greater (P < 0.001) weights of full small intestine and mesenteric fat than HF heifers. These findings demonstrate that, despite similar rates of gain, limit-feeding high-concentrate diets can alter the composition of weight gain, favoring fat, muscle, and GIT development, potentially altering dam efficiency throughout her productive life. [ABSTRACT FROM AUTHOR]

This experiment aimed to evaluate the effects of herbal vitamin C at different levels on tilapia (Oreochromis spp.) growth, potential DNA damage, and the metabolomic profile of water effluent. Forty-five tilapias were housed in separate plastic tanks (80 L), and these were randomly assigned to three treatments: (a) a commercial diet (CD) only; (Nutripec Purina®); (b) the commercial diet plus 250 mg of herbal vitamin C (HVC)/kg (CD250); and (c) the commercial diet plus 500 mg of HVC/kg (CD500). Biometric measurements were taken each week, blood samples were collected from the caudal vein on the final day, and water effluent was taken each week and immediately frozen (−80 °C) until further analysis (gas chromatography/mass spectrometry (GC/MS) systems). Data were completely randomized with a 2 × 2 factorial arrangement of treatments. Upon including herbal vitamin C, the final BW (p = 0.05) and BWG (p = 0.06) increased linearly. Herbal vitamin C decreases DNA damage (p ≥ 0.05). PLS-DA showed a 41.6% variation between treatments in the water samples. Fifteen metabolites had the best association between treatments, with a stronger correlation with CD500. Herbal vitamin C could improve fish performance, prevent DNA damage, and influence changes in the metabolomic profile of the water. [ABSTRACT FROM AUTHOR]

BACKGROUND During anaerobic digestion of wastes, volatile fatty acid (VFA) production has been studied, but little attention has been paid to alcohols and lactic acid. Thermodynamically, lactic acid and alcohols are better substrates to produce methane than other VFA. This research identified the metabolites produced during the fermentation of the organic fraction of municipal solid waste and studied their methanization in a second stage. Analysis of the methane production curves is provided and explained according to Gibbʼs free energy of acetogenesis and methanogenesis. Based on the Michaelis–Menten model, a kinetic analysis is presented. RESULTS: The specific methane production of the identified acids and alcohols are acetic acid, 343 NL/kgCOD; ethanol, 296; methanol, 181; butyric acid, 108; lactic acid, 64. Lactic and butyric acids present a long adaptation phase followed by a fast and short methane production. Acetic acid and ethanol finished the reaction in less than 16 h. The highest methane production rates (Vmax) were for butyric acid, methanol, and ethanol with 2136, 1934, and 1928 NmL L–1, respectively. The best affinity (lowest Km) values were for acetic and lactic acids and ethanol with 1.2, 1.9, and 2.0 gCOD L–1. CONCLUSION: Together, acetic acid and ethanol represent 92% of all fermentation products. No endogenous methane production was observed during the methanization from acetic acid and ethanol. The highest specific methane production belongs to acetic acid (98% of the theoretical) and the lowest corresponds to lactic acid. Except for propionic acid, the methanization of the selected substrates follows the Michaelis and Menten model. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Alloying of Ni with Fe or Co has been shown to reduce primary damage production under ion irradiation. Similar results have been obtained from classical molecular dynamics simulations of 1, 10, 20, and 40 keV collision cascades in Ni, NiFe, and NiCo. In all cases, a mix of imperfect stacking fault tetrahedra, faulted loops with a 1/3(111) Burgers vector, and glissile interstitial loops with a 1/2(110) Burgers vector were formed, along with small sessile point defect complexes and clusters. Primary damage reduction occurs by three mechanisms. First, Ni-Co, Ni-Fe, Co-Co, and Fe-Fe short-distance repulsive interactions are stiffer than Ni-Ni interactions, which lead to a decrease in damage formation during the transition from the supersonic ballistic regime to the sonic regime. This largely controls final defect production. Second, alloying decreases thermal conductivity, leading to a longer thermal spike lifetime. The associated annealing reduces final damage production. These two mechanisms are especially important at cascades energies less than 40 keV. Third, at the higher energies, the production of large defect clusters by subcascades is inhibited in the alloys. A number of challenges and limitations pertaining to predictive atomistic modeling of alloys under high-energy particle irradiation are discussed. [ABSTRACT FROM AUTHOR]

The objective was to characterize the effects of a supplemental Herbal Antibiotics Source (HAnS) on performance, blood chemistry, blood cells, and antibody counts of Holstein calves. Forty calves (initial BW 45.8 ± 7.2 kg) were randomly assigned to treatments: 0, 3, 4, and 5 g d−1 HAnS. The additive improved hip height and thoracic girth. The reduction of starter diet intake among individuals varied greatly, while milk replacer intake increased. HAnS at intermediate doses reduced the cases of pneumonia. It also linearly reduced the blood serum glucose and B-OH butyrate. Urea and monocytes showed a quadratic response, and basophils decreased. HAnS improves calf development at intermediate doses and reduces the incidence of diseases. [ABSTRACT FROM AUTHOR]

Maternal nutrition in the periconceptional period influences gene regulation in the fetal liver across generations, affecting long-term metabolism. This study aimed to examine the effects of the rate of body weight (BW) gain of the dam (F0) during early gestation on the differential gene expression of the liver of first (F1) and second-generation (F2) offspring. Crossbred Angus heifers (F0) were assigned into two groups based on their targeted rate of BW gain during the first 84 d of gestation: low gain (LG; 0.28 kg/d; n = 8) or moderate gain (MG; 0.79 kg/d; n = 8). Following this period, all heifers (F0) were kept on a forage-based diet until the F1 offspring were weaned at 8 mo. The F1 heifers underwent estrus synchronization and were artificially inseminated at 15 mo of age. Liver samples were obtained from the F1 heifers at birth and later when harvested at 84 d of gestation, along with liver samples from their F2 fetuses, for a comprehensive multigenerational RNA-Seq analysis. Differentially expressed genes (DEGs) were identified using the DESeq2 R-package, focusing on significant genes determined by a P-value ≤ 0.05 and a log2 fold change |0.5|. Metabolic pathways and biological processes were analyzed using the WebGestalt tool to understand the implications of the observed gene expression changes. At birth, F1 heifers from MG dams exhibited 281 DEGs, comprising 152 downregulated and 129 upregulated genes compared with the offspring of LG dams. These genes were over-represented in lipid metabolism, cellular homeostasis, and signaling pathways, such as MAPK and chemokine signaling. At harvest, 159 DEGs were identified in F1 heifers, with 67 genes downregulated and 92 genes upregulated in the MG group. These genes were related to cellular morphogenesis and biogenesis processes, with a notable downregulation of metabolic pathways. For the F2 fetuses, 192 DEGs were identified, where 71 genes were downregulated, and 121 genes were upregulated. These genes were involved in biological functions such as peptide secretion to cell proliferation and signaling pathways, including PI3KAkt and Hippo signaling. The analysis of DEGs shared between F1 heifers and F2 fetuses highlighted the influence of the moderate BW weight gain of the F0 dams. At birth and harvest, F1 heifers shared three genes (NAV2, FAM131C, SH3D21). F1 heifers at birth and F2 fetuses shared five genes (CD3E, H1-12, SLC7A11, PIP4P2, ENSBTAG00000051730). From the harvest at d 84 in F1 heifers and F2 fetuses, five genes were shared (DCDC2, RIN1, ENSBTAG00000008911, ENSBTAG00000040518, ENSBTAG00000048049). No DEGs were shared across all comparisons. These findings emphasize the multigenerational impact of early gestational BW gain of the dam on liver gene expression, influencing metabolic pathways and signaling across generations. [ABSTRACT FROM AUTHOR]

In tropical beef cattle production systems, the impact of seasonality may be particularly challenging for young cows (primiparous or secondiparous) due to their increased nutritional requirements, encompassing maintenance, growth, gestation, and, in the case of secondiparous cows, lactation. Literature indicates that extending the duration of lactation during gestation is associated with decreased performance of progeny in their postnatal life. Therefore, implementing an early weaning approach can be an effective strategy to alleviate the nutritional demands of lactation in dams, thereby allocating more nutrients for fetal growth. This study aimed to evaluate the effect of early weaning on the feedlot performance of progeny that were in utero at the time of weaning intervention. To create experimental units, secondiparous and multiparous Nellore cows were assigned to one of two weaning strategies, where suckling calves were either; 1) early weaned 150 d (EW); or 2) conventional weaned at 240 d (CW). All calves were weaned at 150 d of lactation in 2022. Three bulls were used: Bull 1: had 13 calves with multiparous cows, had 7 calves with secondiparous cows, comprising 11 EW and 9 CW; Bull 2: had 10 calves with multiparous cows, had 6 calves with secondiparous cows, comprising 6 EW and 10 CW; and Bull 3: had 7 calves with multiparous cows, had 15 calves with secondiparous cows, comprising 11 EW and 11 CW. All cows were managed similarly after weaning, and through parturition, and weaning of subsequent calf, with resulting calves used for the current experiment. Nellore bulls (n = 57) with an initial body weight (BW) of 417.23 ± 9.12 kg and 18 mo of age were allocated to feedlot pens (equipped with Intergado equipment) and fed a common total mixed ration (80:20; concentrate:corn silage) for 97 ± 1.60 d. Bulls were distributed in a randomized complete block in a 2 × 2 factorial arrangement, considering dam weaning strategy in the previous lactation (EW and CW) and dam parity at subsequent calving (multiparous or secondiparous cows, MC and SC, respectively). Data were analyzed using PROC MIXED of SAS 9.4, with a model including the effects of dam weaning strategy, dam parity, and their interaction. Data were considered significant when P values were less than 0.05 and indicated a trend when 0.05 < P ≤ 0.10. There was an interaction between weaning strategy and cow parity, with calves born to SC-CW having reduced initial (P = 0.04) and final BW (P = 0.01) compared with all other groups (Figure 1 and 2). Steers from MC had greater dry matter intake (P = 0.003), and greater biological efficiency (P = 0.03; Table 1). Early weaning improved the final BW of steers born to secondiparous cows, suggesting it could be a strategy to enhance the performance of offspring and the reproductive performance of both secondiparous and multiparous cows. [ABSTRACT FROM AUTHOR]

Single-phase high- and medium-entropy alloys with face-centred cubic (fcc) structure can exhibit high tensile ductility1,2 and excellent toughness2,3, but their room-temperature strengths are low1–3. Dislocation obstacles such as grain boundaries4, twin boundaries5, solute atoms6 and precipitates7–9 can increase strength. However, with few exceptions8–11, such obstacles tend to decrease ductility. Interestingly, precipitates can also hinder phase transformations12,13. Here, using a model, precipitate-strengthened, Fe–Ni–Al–Ti medium-entropy alloy, we demonstrate a strategy that combines these dual functions in a single alloy. The nanoprecipitates in our alloy, in addition to providing conventional strengthening of the matrix, also modulate its transformation from fcc-austenite to body-centred cubic (bcc) martensite, constraining it to remain as metastable fcc after quenching through the transformation temperature. During subsequent tensile testing, the matrix progressively transforms to bcc-martensite, enabling substantial increases in strength, work hardening and ductility. This use of nanoprecipitates exploits synergies between precipitation strengthening and transformation-induced plasticity, resulting in simultaneous enhancement of tensile strength and uniform elongation. Our findings demonstrate how synergistic deformation mechanisms can be deliberately activated, exactly when needed, by altering precipitate characteristics (such as size, spacing, and so on), along with the chemical driving force for phase transformation, to optimize strength and ductility.Increased strength and ductility in a medium-entropy alloy of Fe, Ni, Al and Ti is demonstrated using nanoprecipitates that simultaneously hinder phase transformation and block dislocation motion. [ABSTRACT FROM AUTHOR]

The concept of quasi-particles forms the theoretical basis of our microscopic understanding of emergent phenomena associated with quantum-mechanical many-body interactions. However, the quasi-particle theory in disordered materials has proven difficult, resulting in the predominance of mean-field solutions. Here, we report first-principles phonon calculations and inelastic X-ray and neutron-scattering measurements on equiatomic alloys (NiCo, NiFe, AgPd, and NiFeCo) with force-constant dominant disorder—confronting a key 50-year-old assumption in the Hamiltonian of all mean-field quasi-particle solutions for off-diagonal disorder. Our results have revealed the presence of a large, and heretofore unrecognized, impact of local chemical environments on the distribution of the species-pair-resolved force-constant disorder that can dominate phonon scattering. This discovery not only identifies a critical analysis issue that has broad implications for other elementary excitations, such as magnons and skyrmions in magnetic alloys, but also provides an important tool for the design of materials with ultralow thermal conductivities. [ABSTRACT FROM AUTHOR]

Introduction: early weaning is a practice that promotes the recovery of body reserves in pregnant cows when applied to breeding herds under grazing‚ which can influence progeny’s performance and the dam’s fertility in the next breeding season. Objective: to assess the effect of early weaning (PD) at 150 days and compare it with conventional weaning (CW) at 240 days of primiparous (PC) and multiparous (MC; ± 6 births) cows on maternal performance. Methods: fifty-nine cows with 30 to 60 days of lactation and body weight (BW) of 453 ± 5.4 at insemination (FTAI) were allocated in a completely randomized design with a 2 × 2 factorial arrangement‚ as follows: two weaning times (EW and CW) and two parity categories (PC and MC). The cows were kept on Brachiaria spp. - pasture and received mineral salt ad libitum. Body condition score (BCS) and BW were recorded during FTAI‚ days 150 and 240 of lactation and prepartum (270 days of gestation). From BCS and BW data‚ pregnant shrunk BW (SBWpreg)‚ non-pregnant shrunk BW (SBWnp)‚ and pregnancy components (PREG; gravid uterus and mammary gland) were estimated. The data were analyzed using the PROC MIXED of SAS 9.3 with a p ≤ 0.05. Results: interaction weaning by time (W × T; p < 0.001) and category by time (p = 0.039) for BCS with 0.8 less score in CW cows from weaning to 240 days and in the prepartum than EW dams. Regarding the category‚ PC had 0.6 less score in the prepartum period than the MC group. Body weight and SBWpreg showed a W×T interaction (p < 0.001)‚ with EW cows on average 45 kg heavier at 240 days (conventional weaning) and in the prepartum compared to CW dams. A W × T Interaction (p < 0.001) for SBWnp‚ with a gain of 31 kg from weaning at 150 to 240 days (conventional weaning) and being heavier than the CW group (508 vs. 462 kg‚ respectively). EW cows from FTAI up to 240 days gained 64 kg and then lost 24 kg prepartum‚ while CW cows gained 32 kg up to 150 days‚ and then there was a loss of 19 kg up to prepartum. EW dams tended (W × T; p = 0.079) to have higher PREG weights from 240 days to prepartum compared to CW cows. Conclusions: early weaning is a practice that promotes an increase in maternal body reserves in any parity category. [ABSTRACT FROM AUTHOR]

Objective: This experiment was designed to evaluate the effect of supplementation with soybean or canola oil on milk production and the composition of long chain fatty acids as well as weight changes in the goats and their kids. Methods: Thirty nine mulitparous crossed Alpine×Nubian goats (initial body weight [BW] 43.5±1.7 kg) from the day of parturition were assigned to the treatments: grazing control (n = 15); grazing plus 20 mL/goat/d of supplemental soybean oil (n = 12); and grazing plus 20 mL/goat/d of supplemental canola oil (n = 12) from November 26, 2014 to March 7, 2015. The planned contrasts were: CI (control vs supplemented with oils); CII (soybean vs canola oil) to compare the treatment effects. Results: The vegetable oil supplementation reduced weight losses in lactating goats (CI: -0.060 vs 0.090 kg/d; p = 0.03) but did not improve milk production or affect kids' growth. The content of C4, C6, C8, C10, C11, C14, and C18:1n9t in the milk was increased (p<0.05) with respect to control. However, C12, C14, C16, C18, C18:1n9c, C18:2n6c, and C18:3n3 were reduced (p<0.05) in supplemented goats. Conjugated linoleic acid (CLA) was increased (p<0.05) in goats supplemented with oils compared to the control group. Conclusion: Supplementation with 20 mL/d of soybean or canola oil did not affect milk production or kids' performance; however, it increased CLA concentration and reduced the reduced weight losses in lactating goats. [ABSTRACT FROM AUTHOR]

The metallic Zn 2 p photoemission spectra hold a complex background that requires individual assignment of Shirley background for each peak comprising the spectra. For this reason, a close fit requires the use of the Shirley-Vegh-Salvi-Castle background-type under the active background approach. We found that the intensity of the plasmon peaks and their associated background cannot be described through existing energy loss (intrinsic and extrinsic) formalisms. We also analyzed the Zn 2 p and O 1 s spectra for the initial stages of oxide formation at various oxygen exposures. We found that the composition of the oxide layer is ZnO1.00±0.10 for all exposures, suggesting that our assessment of the primary function of metallic Zn is accurate and can be employed for quantitative studies. We also present a set of parameters to accurately fit and resolve the metallic and oxide Zn 2 p peaks. [ABSTRACT FROM AUTHOR]

A quantitative study of the surface composition of ferric oxide employing photoemission spectra is presented. It was possible to accurately reproduce the expected composition (Fe2.00±0.05O3) by modeling the background as a combination of Shirley-type (Shirley-Vegh-Salvi-Castle) and slope backgrounds through the active approach. The line-shape employed to fit apparent peak asymmetries was the double-Lorentzian. It was possible to resolve a previously unreported satellite located at ~729 eV. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Historically, alloy development with better radiation performance has been focused on traditional alloys with one or two principal element(s) and minor alloying elements, where enhanced radiation resistance depends on microstructural or nanoscale features to mitigate displacement damage. In sharp contrast to traditional alloys, recent advances of single-phase concentrated solid solution alloys (SP-CSAs) have opened up new frontiers in materials research. In these alloys, a random arrangement of multiple elemental species on a crystalline lattice results in disordered local chemical environments and unique site-to-site lattice distortions. Based on closely integrated computational and experimental studies using a novel set of SP-CSAs in a face-centered cubic structure, we have explicitly demonstrated that increasing chemical disorder can lead to a substantial reduction in electron mean free paths, as well as electrical and thermal conductivity, which results in slower heat dissipation in SP-CSAs. The chemical disorder also has a significant impact on defect evolution under ion irradiation. Considerable improvement in radiation resistance is observed with increasing chemical disorder at electronic and atomic levels. The insights into defect dynamics may provide a basis for understanding elemental effects on evolution of radiation damage in irradiated materials and may inspire new design principles of radiation-tolerant structural alloys for advanced energy systems. [ABSTRACT FROM PUBLISHER]

The objective of this study was to evaluate the effects of the addition of two levels of calcium propionate on lamb performance and some carcass characteristics. Twenty-one male Creole lambs with an initial weight of 25.3 ± 3.3 kg were randomly assigned to one of the following treatments: 0, 10, and 20 g of calcium propionate/kg of diet (dry matter basis). Intake, daily gain, feed conversion, carcass weight, and rib eye area were not affected (P < 0.05) by calcium propionate addition. Ruminal fermentation was not altered (rumen pH, volatile fatty acids concentration, and fermentation pattern), and ruminal ammonia-N presented a quadratic response (P < 0.05). In fat from the longissimus dorsi muscle, oleic acid showed a linear decrease (P < 0.05) and a-linolenic presented a linear increment (P < 0.05). The addition of 10 or 20 g of calcium propionate in diets containing 350 g/kg grain and 100 g/kg molasses did not modify the productive performance of lambs or ruminal fermentation, and minor changes were detected in long-chain fatty acid in intramuscular fat. [ABSTRACT FROM AUTHOR]

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The objective was to evaluate the effect of different forage allowance in the mid to late gestation on the performance of the cow/calf pair. The experiment started at the final 151 days of gestation (D-151) until weaning (D205). Nellore cows pregnant with male calves [n = 56; 444±42 kg body weight (BW)] were blocked by the initial BW and randomly assigned to receive different forage allowances (FA): (1) Low (LFA; 2.81 kgDM)/kgBW; and (2) High (HFA; 7.58 kgDM/kgBW) until calving (d0); divided into 6 blocks and 12 paddocks of 7.5 ha each consisting of forage Urochloa brizantha cv. Marandu, without application of treatment after d0. Cows received a protein supplement (33% TDN and 50% CP) with a supply of 0.1% BW/day from d-151 to d0 and ad libitum mineral mixture from d0 to d205. Fasting BW, body condition score (BCS) on d-151, d0 and d205, mean daily gain (ADG), and milk production and composition of cows on d30, d120 and d205, and d0, d120 and d205 were used in determining ADG. The data analyzed by ANOVA using PROC MIXED, SAS 9.4. HFA cows showed greater BW, ADG and BCS with the FA × period interaction effect (P< 0.01) in D-151 to the D0. The BW was similar for cows kept in LFA and HFA, greater ADG for LFA; however, the BCS was greater for HFA from d0 to d205. Milk production and composition were not affected by the FA x period (P≥0.21). The performance of HFA calves showed greater BW with the interaction effect of FA x period (P=0.05) and without effect of FA x period (P=0.13) on ADG. In conclusion, the low forage allowance promoted a feed restriction capable of reducing the performance of the cows and consequently reducing the performance of the offspring from birth to weaning. [ABSTRACT FROM AUTHOR]

We examined the effect on depressive symptoms of a peer network-oriented intervention effective in reducing sexual risk behavior and methamphetamine (MA) use. Current Thai MA users aged 18-25 years and their drug and/or sex network members enrolled in a randomized controlled trial with 4 follow-ups over 12 months. A total of 415 index participants recruited 568 network members. Linear repeated measures models were fit with depressive symptoms (Center for Epidemiologic Studies Depression Scale [CES-D]) as the outcome. Among indexes in the intervention condition, mean CES-D decreased from 20.0 to 15.7 (p < 0.0001) over follow-up. Controlling for covariates and changes in MA and alcohol use, CES-D in this group decreased by 0.35 points per month (95% confidence interval, 0.45, -0.25). All other groups showed minimal changes in CES-D score. The peer-oriented, community-based intervention designed to reduce MA use and sexual risk behavior also resulted in substantial reduction in depressive symptoms, independent of changes in MA use. [ABSTRACT FROM AUTHOR]

The discovery of superconductivity at 39 K in MgB2 has been catching the attention of scientists due to the possibility of applying the material in magnets and electronic devices operating with cryocoolers (temperatures around 20 K). In the present work, a methodology to optimize the critical current densities of this material is described. MgB2 bulk samples were prepared and analyzed with the addition of other diborides with the same C32 hexagonal structure as MgB2 (TaB2, ZrB2, VB2, and AlB2) and with simultaneous addition of SiC. Microstructural characterization, performed using SEM+EDS and XRD, was extremely important to determine the distribution and compositional characterization of the superconducting phase. Magnetic superconducting characterization using SQUID was performed to determine the best material addition. As a result we could analyze the behavior of each addition on the current transport capacity, including an analysis of the magnetic flux pinning mechanisms. [ABSTRACT FROM AUTHOR]

Understanding soil test phosphorus (STP) and surface run-off phosphorus (P) relationships for soils is necessary for P management. The objective of the study was to evaluate the efficacy of various soil test indices to predict P losses in surface run-off. Selected sites were subjected to in situ rainfall simulations according to the protocol of the National Phosphorus Research Project ( NPRP, 2001 ). P from a composite of twenty-four 2.0-cm-diameter core soil samples (0–5 cm) was extracted using the Olsen, Bray–Kurtz, Mehlich III, distilled water and 0.01 m calcium chloride procedures. All of these P extraction methods explained a significant amount of variability in surface run-off total dissolved P [TP (<0.45)] ( r2 ≥ 0.67; P ≤ 0.01), where 0.45 is the filter pore diameter in microns. Multiple regression models showed extractable P to be the best soil predictor of surface run-off TP (<0.45) among the studied soils. Despite extraction method or soil type, extractable P was the best soil predictor of surface run-off TP (<0.45). Either agronomic (0.92 ≤ r2 ≤ 0.96) or environmental (0.94 ≤ r2 ≤ 0.96) soil tests were effective in estimating surface run-off TP (<0.45) in select Mollisols. [ABSTRACT FROM AUTHOR]

Two different approaches to explain and predict the types of magnetic ordering in the 3d metal series and their compounds are reviewed. According to the crossing theorem of Heine and Samson, the effective exchange coupling changes sign from negative (antiferromagnetic ordering) in the middle of 3d band to positive (ferromagnetic ordering) for the nearly empty or nearly filled d band cases. On the other hand, the analytical properties of the Crystal Orbital Hamilton Population, which is a measure of chemical bonding, predict only one crossing at the center of the band in the region of nonbonding states. Thus intermetallic compounds with Fermi energies falling within metal–metal nonbonding states are ordered antiferromagnetically whereas they order ferromagnetically when the Fermi levels fall within antibonding states. The general character of these dependencies is demonstrated for various examples containing the magnetically active 3d metals, examples that include the bcc metals, Heusler alloys, and a series of novel quaternary intermetallic borides. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2008 [ABSTRACT FROM AUTHOR]