The impact of boreal forest fire on climate warming

We report measurements and analysis of a boreal forest fire, integrating the effects of greenhouse gases, aerosols, black carbon deposition on snow and sea ice, and postfire changes in surface albedo. The net effect of all agents was to increase radiative forcing during the first year (34 +/- 31 Watts per square meter of burned area), but to decrease radiative forcing when averaged over an 80-year fire cycle (-2.3 +/- 2.2 Watts per square meter) because multidecadal increases in surface albedo had a larger impact than fire-emitted greenhouse gases. This result implies that future increases in boreal fire may not accelerate climate warming.     

Second-harmonic generation from magnetic metamaterials

We observe second-harmonic generation from metamaterials composed of split-ring resonators excited at 1.5-micrometer wavelength. Much larger signals are detected when magnetic-dipole resonances are excited, as compared with purely electric-dipole resonances. The experiments are consistent with calculations based on the magnetic component of the Lorentz force exerted on metal electrons-an intrinsic second-harmonic generation mechanism that plays no role in natural materials. This unusual mechanism becomes relevant in our work as a result of the enhancement and the orientation of the local magnetic fields associated with the magnetic-dipole resonances of the split-ring resonators.     

Evaluation of genetic and metabolic predispositions and nutritional risk factors for pasture-associated laminitis in ponies

OBJECTIVE: To evaluate genetic and metabolic predispositions and nutritional risk factors for development of pasture-associated laminitis in ponies. DESIGN: Observational cohort study. ANIMALS: 160 ponies. PROCEDURES: A previous diagnosis of laminitis was used to differentiate 54 ponies (PL group) from 106 nonlaminitic ponies (NL group). Pedigree analysis was used to determine a mode of inheritance for ponies with a previous diagnosis of laminitis. In early March, ponies were weighed and scored for body condition and basal venous blood samples were obtained. Plasma was analyzed for glucose, insulin, triglycerides, nonesterified fatty acids, and cortisol concentrations. Basal proxies for insulin sensitivity (reciprocal of the square root of insulin [RISQI]) and insulin secretory response (modified insulin-to-glucose ratio [MIRG]) were calculated. Observations were repeated in May, when some ponies had signs of clinical laminitis. RESULTS: A previous diagnosis of laminitis was consistent with the expected inheritance of a dominant major gene or genes with reduced penetrance. A prelaminitic metabolic profile was defined on the basis of body condition, plasma triglyceride concentration, RISQI, and MIRG. Meeting > or = 3 of these criteria differentiated PL- from NL-group ponies with a total predictive power of 78%. Determination of prelaminitic metabolic syndrome in March predicted 11 of 13 cases of clinical laminitis observed in May when pasture starch concentration was high. CONCLUSIONS AND CLINICAL RELEVANCE: Prelaminitic metabolic syndrome in apparently healthy ponies is comparable to metabolic syndromes in humans and is the first such set of risk factors to be supported by data in equids. Prelaminitic metabolic syndrome identifies ponies requiring special management, such as avoiding high starch intake that exacerbates insulin resistance.     

Cavity cooling below the recoil limit

Conventional laser cooling relies on repeated electronic excitations by near-resonant light, which constrains its area of application to a selected number of atomic species prepared at moderate particle densities. Optical cavities with sufficiently large Purcell factors allow for laser cooling schemes, avoiding these limitations. Here, we report on an atom-cavity system, combining a Purcell factor above 40 with a cavity bandwidth below the recoil frequency associated with the kinetic energy transfer in a single photon scattering event. This lets us access a yet-unexplored regime of atom-cavity interactions, in which the atomic motion can be manipulated by targeted dissipation with sub-recoil resolution. We demonstrate cavity-induced heating of a Bose-Einstein condensate and subsequent cooling at particle densities and temperatures incompatible with conventional laser cooling.     

Don't look back in anger! Responsiveness to missed chances in successful and nonsuccessful aging

Life-span theories explain successful aging with an adaptive management of emotional experiences like regret. As opportunities to undo regrettable situations decline with age, a reduced engagement into these situations represents a potentially protective strategy to maintain well-being in older age. Yet, little is known about the underlying neurobiological mechanisms supporting this claim. We used a multimodal psychophysiological approach in combination with a sequential risk-taking task that induces the feeling of regret and investigated young as well as emotionally successfully and unsuccessfully (i.e., late-life depressed) aged participants. Responsiveness to regret was specifically reduced in successful aging paralleled by autonomic and frontostriatal characteristics indicating adaptive shifts in emotion regulation. Our results suggest that disengagement from regret reflects a critical resilience factor for emotional health in older age.     

Feed enzyme supplementation does not ameliorate foot pad dermatitis in broiler chickens fed on a corn-soyabean diet

1.?Foot Pad Dermatitis (FPD) can be a serious health, quality and welfare problem in poultry production, with a significant affect on the economics of production. The physico-chemical properties of (NSP) have been correlated with increases in excreta viscosity and adherence, and hence FPD in broiler chickens.

2.?Two broiler experiments were conducted to evaluate the effects of different dietary non-starch polisaccharide (NSP) applications to corn-soyabean based diets in replicated floor pens. In addition to live performance, the incidence and severity of FPD was scored and, in experiment 2, intestinal viscosity and ammonia volatilization were measured.

3.?Live performance did not vary with the different treatments in either experiment and the incidence and severity of FPD, and ammionia volatisation in experiment 2, were unaffected. However, birds reared on enzyme supplemented diets had lower (P? 4.?In this study with corn-soyabean meal based diets, dietary enzyme supplementation had no affect on the incidence and severity of FPD. The lack of an association between the excreta viscosity and FPD is attributed to the multifactorial etiology of this condition.     

Effects of establishment method and fall stocking rate of wheat pasture on forage mass, forage chemical composition, and performance of growing steers

Stocking rate is a fundamental variable for managing pastures, and there is a distinct relationship between stocking rate and animal performance for each forage type. This research was conducted to determine the effects of fall stocking rate (SR) and method of establishment of wheat pasture planted into dedicated crop fields on animal performance during the fall and subsequent spring. There was a factorial arrangement of tillage methods used in the establishment of wheat pasture and fall stocking rates. Tillage treatments included 1) CT, seed sown into a prepared seedbed, 2) RT, a single pass with a light disk followed by broadcasting of seed, or 3) NT, direct seeding into the undisturbed stubble of the grazed-out wheat pasture from the previous year. The fixed SR during the fall were 1.9, 2.5, and 3.7 growing beef steers (Bos taurus L.)/ha. In the spring all pastures were grazed at the same fixed SR by steers for graze out. Data were analyzed using the mixed procedure of SAS as a randomized complete block design with field as the experimental unit and year as the block. Forage mass, forage nutritive composition, and animal performance during the fall or spring were not affected (P ≥ 0.14) by tillage method. During the fall grazing season, with increasing SR there were linear (P < 0.01) decreases in BW of steers upon removal from pasture, BW gain per steer, and ADG, whereas grazing-day per hectare and BW gain per hectare increased linearly (P < 0.01) with increasing SR. The carryover effects of fall SR into the spring grazing season decreased (P< 0.01) grazing-day per hectare and tended (P ≤ 0.09) to produce quadratic changes in BW upon removal from pasture and BW gain per hectare. Across the fall and spring grazing seasons, grazing-day per hectare increased linearly (P < 0.01) with greater SR, and BW gain per hectare increased quadratically (P = 0.02) with increased fall SR. A tillage treatment by fall SR interaction (P = 0.10) indicates that although there was no difference (P ≥ 0.12) due to tillage treatment in BW gain per hectare at 1.9 or 2.5 SR, NT fields produced (P ≤ 0.04) more BW gain per hectare than CT or RT at the 3.7 SR. Although increasing SR of growing steers leads to reduced animal performance in the fall and reduced carrying capacity in the spring, NT appears to be capable of withstanding greater fall SR with less impact on total production per hectare than CT or RT.     

Effects of different media on proliferation and differentiation capacity of canine, equine and porcine adipose derived stem cells

Adult stem cells are of particular interest for therapeutic use in the field of regenerative medicine. Adipose-derived mesenchymal stem cells (ASCs) are an attractive stem cell source for all fields of regenerative medicine because adipose tissue - and therewith cells - can easily be harvested from each donor. However, common expansion using fetal bovine serum (FBS) can not be used for clinical applications as xenogenic proteins must be avoided. Adipose tissue from equine, canine and porcine donors was digested with collagenase to isolate ASCs. ASCs were either expanded in a cell culture medium supplemented with FBS or in a serum-free medium (UltraCulture; UC) supplemented with a serum substitute (UltroserG). From all three animal species, the adipogenic and osteogenic differentiation potential of ASCs cultured with different media was analyzed in vitro. Cell proliferation analysis showed a population doubling time of 48-68 h for canine cells, 54-65 h for porcine cells and 54-70 h for equine cells, expanded in different media. Except for porcine ASCs, cells cultured in media supplemented with FBS grew faster than cells expanded in UC medium with UltroserG. Yet, all cells maintained their potential to differentiate into adipocytes and osteoblasts. UltraCulture medium containing UltroserG can for all examined species be recommended if FBS needs to be avoided in the expansion of donor-derived (stem) cells.