Does the Establishment of Sustainable Use Reserves Affect Fire Management in the Humid Tropics?

Tropical forests are experiencing a growing fire problem driven by climatic change, agricultural expansion and forest degradation. Protected areas are an important feature of forest protection strategies, and sustainable use reserves (SURs) may be reducing fire prevalence since they promote sustainable livelihoods and resource management. However, the use of fire in swidden agriculture, and other forms of land management, may be undermining the effectiveness of SURs in meeting their conservation and sustainable development goals. We analyse MODIS derived hot pixels, TRMM rainfall data, Terra-Class land cover data, socio-ecological data from the Brazilian agro-census and the spatial extent of rivers and roads to evaluate whether the designation of SURs reduces fire occurrence in the Brazilian Amazon. Specifically, we ask (1) a. Is SUR location (i.e., de facto) or (1) b. designation (i.e. de jure) the driving factor affecting performance in terms of the spatial density of fires?, and (2), Does SUR creation affect fire management (i.e., the timing of fires in relation to previous rainfall)? We demonstrate that pre-protection baselines are crucial for understanding reserve performance. We show that reserve creation had no discernible impact on fire density, and that fires were less prevalent in SURs due to their characteristics of sparser human settlement and remoteness, rather than their status de jure. In addition, the timing of fires in relation to rainfall, indicative of local fire management and adherence to environmental law, did not improve following SUR creation. These results challenge the notion that SURs promote environmentally sensitive fire-management, and suggest that SURs in Amazonia will require special attention if they are to curtail future accidental wildfires, particularly as plans to expand the road infrastructure throughout the region are realised. Greater investment to support improved fire management by farmers living in reserves, in addition to other fire users, will be necessary to help ameliorate these threats

New seven membered palladacycles: C-Br bond activation of 2-bromo-pyridine derivative by Pd(II)

C-Br bond activation followed by a C-C coupling reaction of the 2-bromo-pyridyl unit of [1-phenyl-2-(6-bromopyridin-2-yl)-benzoimidazole] was performed by Pd(CH2CMe2-o-C6H 4)(η4-COD). Two new seven membered palladacycles were obtained. A combined experimental and theoretical DFT study elucidates the mechanism for this reaction. This journal is © The Royal Society of Chemistry.This research was supported by grants from the Universidad de Guanajuato (UG-2008) and SEP/CONACYT (México) (02-44420). J. O. C. J.-H. gratefully acknowledges the Carl Trygger Foundation for support through postdoctoral fellowship (CTS-09:144). J. N.-C. thanks the CONACYT for a doctoral fellowship (329449).Peer Reviewe

New seven membered palladacycles: C-Br bond activation of 2-bromo-pyridine derivative by Pd(II)

C-Br bond activation followed by a C-C coupling reaction of the 2-bromo-pyridyl unit of [1-phenyl-2-(6-bromopyridin-2-yl)-benzoimidazole] was performed by Pd(CH2CMe2-o-C6H 4)(η4-COD). Two new seven membered palladacycles were obtained. A combined experimental and theoretical DFT study elucidates the mechanism for this reaction. This journal is © The Royal Society of Chemistry.This research was supported by grants from the Universidad de Guanajuato (UG-2008) and SEP/CONACYT (México) (02-44420). J. O. C. J.-H. gratefully acknowledges the Carl Trygger Foundation for support through postdoctoral fellowship (CTS-09:144). J. N.-C. thanks the CONACYT for a doctoral fellowship (329449).Peer Reviewe

Prompt and non-prompt J/ψ production at midrapidity in Pb–Pb collisions at sNN \sqrt{s_{\textrm{NN}}} = 5.02 TeV

Abstract The transverse momentum (pT) and centrality dependence of the nuclear modification factor RAA of prompt and non-prompt J/ψ, the latter originating from the weak decays of beauty hadrons, have been measured by the ALICE collaboration in Pb–Pb collisions at $$\sqrt{s_{\textrm{NN}}}$$ s NN = 5.02 TeV. The measurements are carried out through the e+e− decay channel at midrapidity (|y| &lt; 0.9) in the transverse momentum region 1.5 &lt; pT &lt; 10 GeV/c. Both prompt and non-prompt J/ψ measurements indicate a significant suppression for pT &gt; 5 GeV/c, which becomes stronger with increasing collision centrality. The results are consistent with similar LHC measurements in the overlapping pT intervals, and cover the kinematic region down to pT = 1.5 GeV/c at midrapidity, not accessible by other LHC experiments. The suppression of prompt J/ψ in central and semicentral collisions exhibits a decreasing trend towards lower transverse momentum, described within uncertainties by models implementing J/ψ production from recombination of c and $$\overline{\textrm{c}}$$ c ¯ quarks produced independently in different partonic scatterings. At high transverse momentum, transport models including quarkonium dissociation are able to describe the suppression for prompt J/ψ. For non-prompt J/ψ, the suppression predicted by models including both collisional and radiative processes for the computation of the beauty-quark energy loss inside the quark-gluon plasma is consistent with measurements within uncertainties.</jats:p

Light-flavor particle production in high-multiplicity pp collisions at s s \sqrt{\textrm{s}} = 13 TeV as a function of transverse spherocity

Abstract Results on the transverse spherocity dependence of light-flavor particle production (π, K, p, ϕ, K*0, K S 0 $${\textrm{K}}_{\textrm{S}}^0$$ , Λ, Ξ) at midrapidity in high-multiplicity pp collisions at s $$\sqrt{s}$$ = 13 TeV were obtained with the ALICE apparatus. The transverse spherocity estimator S O p T = 1 $$\left({S}_{\textrm{O}}^{p_{\textrm{T}}=1}\right)$$ categorizes events by their azimuthal topology. Utilizing narrow selections on S O p T = 1 $${S}_{\textrm{O}}^{p_{\textrm{T}}=1}$$ , it is possible to contrast particle production in collisions dominated by many soft initial interactions with that observed in collisions dominated by one or more hard scatterings. Results are reported for two multiplicity estimators covering different pseudorapidity regions. The S O p T = 1 $${S}_{\textrm{O}}^{p_{\textrm{T}}=1}$$ estimator is found to effectively constrain the hardness of the events when the midrapidity (|η| < 0.8) estimator is used. The production rates of strange particles are found to be slightly higher for soft isotropic topologies, and severely suppressed in hard jet-like topologies. These effects are more pronounced for hadrons with larger mass and strangeness content, and observed when the topological selection is done within a narrow multiplicity interval. This demonstrates that an important aspect of the universal scaling of strangeness enhancement with final-state multiplicity is that high-multiplicity collisions are dominated by soft, isotropic processes. On the contrary, strangeness production in events with jet-like processes is significantly reduced. The results presented in this article are compared with several QCD-inspired Monte Carlo event generators. Models that incorporate a two-component phenomenology, either through mechanisms accounting for string density, or thermal production, are able to describe the observed strangeness enhancement as a function of S O p T = 1 $${S}_{\textrm{O}}^{p_{\textrm{T}}=1}$$

The ALICE experiment: a journey through QCD

The ALICE experiment was proposed in 1993, to study strongly-interacting matter at extreme energy densities and temperatures. This proposal entailed a comprehensive investigation of nuclear collisions at the LHC. Its physics programme initially focused on the determination of the properties of the quark–gluon plasma (QGP), a deconfined state of quarks and gluons, created in such collisions. The ALICE physics programme has been extended to cover a broader ensemble of observables related to Quantum Chromodynamics (QCD), the theory of strong interactions. The experiment has studied Pb–Pb, Xe–Xe, p–Pb and pp collisions in the multi-TeV centre of mass energy range, during the Run 1–2 data-taking periods at the LHC (2009–2018). The aim of this review is to summarise the key ALICE physics results in this endeavor, and to discuss their implications on the current understanding of the macroscopic and microscopic properties of strongly-interacting matter at the highest temperatures reached in the laboratory. It will review the latest findings on the properties of the QGP created by heavy-ion collisions at LHC energies, and describe the surprising QGP-like effects in pp and p–Pb collisions. Measurements of few-body QCD interactions, and their impact in unraveling the structure of hadrons and hadronic interactions, will be discussed. ALICE results relevant for physics topics outside the realm of QCD will also be touched upon. Finally, prospects for future measurements with the ALICE detector in the context of its planned upgrades will also be briefly described