Sulfur amino acid requirements of broilers from two to five weeks of age

Phase-feeding (PF) in broiler chickens has been researched as a way to reduce feed costs without reducing growth performance and yield. Predicted amino acid requirements for PF are generated using linear regression equations derived from best estimates of lysine (Lys), sulfur amino acid (SAA), and threonine (Thr) requirements. During the late starter and early grower periods, predicted requirements for the SAA methionine (Met) and cysteine (Cys) are higher than levels recommended by the National Research Council (NRC), and previous research suggests that SAA may be lowered during the grower period without sacrificing growth performance or yield. The objective of this study was to estimate Met and Cys requirements for broilers from 2 to 5 weeks of age. In Experiment 1, a Met-deficient corn-peanut meal diet was formulated to contain excess Cys, so that supplemental Met was not utilized for Cys synthesis. The basal diet for Experiment 2 met the Met requirement but was deficient in Cys. Graded levels of Met (0, 0.045, 0.09, 0.135, and 0.225%) and Cys (0, 0.035, 0.070, 0.105, 0.140, 0.175%) were added in Experiments 1 and 2, respectively, and diets were fed to five replicates of five broilers per pen. Broken-line analysis was used to estimate SAA requirements. The digestible Met and Cys requirements from 2 to 5 weeks of age were 0.33% and 0.31%, respectively. Requirement estimates were lower than those predicted by PF or recommended by NRC, indicating that lower SAA levels may be utilized in a PF progra

Neural Blockade Anaesthesia of the Mandibular Nerve and Its Terminal Branches: Rationale for Different Anaesthetic Techniques Including Their Advantages and Disadvantages

Anaesthesia of structures innervated by the mandibular nerve is necessary to provide adequate pain control when performing dental and localised surgical procedures. To date, numerous techniques have been described and, although many of these methods are not used routinely, there are some situations where their application may be indicated. Patient factors as well as anatomical variability of the mandibular nerve and associated structures dictate that no one technique can be universally applied with a 100% success rate. This fact has led to a proliferation of alternative techniques that have appeared in the literature. This selective review of the literature provides a brief description of the different techniques available to the clinician as well as the underlying anatomy which is fundamental to successfully anaesthetising the mandibular nerve

Comparison of three-dimensional printed patient-specific guides versus freehand approach for radial osteotomies in normal dogs: Ex vivo model.

OBJECTIVE To compare the accuracy of three-dimensional (3D) printed patient-specific guide (PSG) with a freehand (FH) approach for radial osteotomies in ex vivo normal dogs. STUDY DESIGN Experimental study. ANIMALS Twenty four ex vivo thoracic limb pairs from normal beagle dogs. METHODS Computed tomography (CT) images were collected preoperatively and postoperatively. Three osteotomies tested (n = 8/group) were: (1) uniplanar 30° frontal plane wedge ostectomy, (2) oblique plane (30° frontal, 15° sagittal) wedge ostectomy, and (3) single oblique plane osteotomy (SOO, 30° frontal, 15° sagittal, and 30° external). Limb pairs were randomized to a 3D PSG or FH approach. The resultant osteotomies were compared with virtual target osteotomies by surface shape-matching postoperative to the preoperative radii. RESULTS The mean ± standard deviation osteotomy angle deviation for all 3D PSG osteotomies (2.8 ± 2.8°, range 0.11-14.1°) was less than for the FH osteotomies (6.4 ± 6.0°, range 0.03-29.7°). No differences were found for osteotomy location in any group. In total, 84% of 3D PSG osteotomies were within 5° deviance from the target compared to 50% of freehand osteotomies. CONCLUSION Three-dimensional PSG improved FH accuracy of osteotomy angle in select planes and the most complex osteotomy orientation in a normal ex vivo radial model. CLINICAL SIGNIFICANCE Three-dimensional PSGs provided more consistent accuracy, which was most notable in complex radial osteotomies. Future work is needed to investigate guided osteotomies in dogs with antebrachial bone deformities

Patterns in island endemic forest-dependent bird research: the Caribbean as a case-study

From Springer Nature via Jisc Publications RouterHistory: received 2018-10-25, rev-recd 2019-03-19, registration 2019-04-26, accepted 2019-04-26, online 2019-05-04, epub 2019-05-04, ppub 2019-06Publication status: PublishedAbstract: Unequal patterns in research effort can result in inaccurate assessments of species extinction risk or ineffective management. A group of notable conservation concern are tropical island endemic birds, many of which are also forest-dependent, which increases their vulnerability to extinction. Yet, island bird species have received limited research attention compared to their continental congeners, despite this taxon being globally regarded as well-studied. We used the insular Caribbean, a globally important endemism hotspot with high rates of deforestation, to explore research bias of island and regional endemic forest-dependent birds. A review of the published literature (n = 992) found no significant increase in the number of studies over the search period. Research effort was significantly higher among species with threatened status, long generation time, wide habitat breadth and low to intermediate elevational distributions. Among family groups, the Psittacidae received the highest research effort, while the Cuculidae were the most underrepresented family (30-fold higher and six-fold less than expected, respectively). We found geographic biases in effort, with Jamaica having six-fold less and Puerto Rico eight times more research than expected for their level of endemism. These patterns likely reflect individual interests and limited capacity and funding, typical of Small Island Developing States. With over 50% of species in this review having declining population trends, we recommend prioritizing research that emphasises conservation- and management-relevant data across underrepresented families and islands, by fostering greater collaboration between researchers, practitioners and the existing local amateur ornithological community

Ultraviolet relaxation dynamics in uracil: Time-resolved photoion yield studies using a laser-based thermal desorption source

Wavelength-dependent measurements of the RNA base uracil, undertaken with nanosecond ultraviolet laser pulses, have previously identified a fragment at m/z = 84 (corresponding to the C3H4N2O+ ion) at excitation wavelengths ≤232 nm. This has been interpreted as a possible signature of a theoretically predicted ultrafast ring-opening occurring on a neutral excited state potential energy surface. To further investigate the dynamics of this mechanism, and also the non-adiabatic dynamics operating more generally in uracil, we have used a newly built ultra-high vacuum spectrometer incorporating a laser-based thermal desorption source to perform time-resolved ion-yield measurements at pump wavelengths of 267 nm, 220 nm, and 200 nm. We also report complementary data obtained for the related species 2-thiouracil following 267 nm excitation. Where direct comparisons can be made (267 nm), our findings are in good agreement with the previously reported measurements conducted on these systems using cold molecular beams, demonstrating that the role of initial internal energy on the excited state dynamics is negligible. Our 220 nm and 200 nm data also represent the first reported ultrafast study of uracil at pump wavelengths 3(1ππ*) state. These measurements do not, however, provide any evidence for the appearance of the m/z = 84 fragment within the first few hundred picoseconds following excitation. This key finding indicates that the detection of this specific species in previous nanosecond work is not directly related to an ultrafast ring-opening process. An alternative excited state process, operating on a more extended time scale, remains an open possibility

Contribution of Sediment to High Enterococcus Counts Along the Northern Gulf of Mexico

Enumeration of enterococci (EN) bacteria in water is an USEPA approved indicator of fecal pollution and the possible presence of enteric pathogens. Along the northern Gulf of Mexico, the water is shallow with a high organic and particulate load because of the Mississippi River discharge. Disturbance of coastal sediments during wind/wave action caused either by the weather or human activities may increase bacterial counts as a result of increased EN persistence in the water column and/or resuspension of EN in the sediment. The goals of this project are to determine the relationship between organic content and EN counts in the water and whether bacterial resuspension from the sediment contributes to elevated EN counts. We found that EN counts in the water were correlated with wave conditions at seven sites along the Mississippi Gulf Coast. During calm wave conditions, low bacterial levels (1.0 – 227 CFU/100mL) were observed in the water with higher counts in the sediment; the reverse was observed (10 – 351 CFU/100mL) during rough wave conditions. EN counts were positively correlated with organic content of the sediment. Wave activity to keep EN in suspension was apparently critical for high counts. EN counts decreased by 50% in 4 hr from 38 to 17 CFU/100mL in the absence of resuspension and decreased to 1 CFU/100mL after 48 hr. EN in the sediment are not stationary as genetic fingerprinting using REP-PCR showed low persistence of specific isolates over time. Jackknife analysis revealed low similarity among EN isolates from the water and sediment collected on the same day and site during calm wave conditions. This shows that EN are not persisting for long periods in the same area but instead are resuspended and redistributed along the coast. Results from this study provide evidence that high organic content and resuspension of isolates from the sediment during periods of strong wave action contribute to high EN counts. Current research on the survival of EN in estuarine habitats will provide insight on the balance between environmental persistence and fecal pollution in causing high EN counts along beaches in the northern Gulf of Mexico

Universal profile of the vortex condensate in two-dimensional turbulence

An inverse turbulent cascade in a restricted two-dimensional periodic domain creates a condensate—a pair of coherent system-size vortices. We perform extensive numerical simulations of this system and carry out theoretical analysis based on momentum and energy exchanges between the turbulence and the vortices. We show that the vortices have a universal internal structure independent of the type of small-scale dissipation, small-scale forcing, and boundary conditions. The theory predicts not only the vortex inner region profile, but also the amplitude, which both perfectly agree with the numerical data