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Robots in complex multi-agent environments should reason about the intentions of observed and currently unobserved agents. In this paper, we present a new learning-based method for prediction and planning in complex multi-agent environments where the states of the other agents are partially-observed. Our approach, Active Visual Planning (AVP), uses high-dimensional observations to learn a flow-based generative model of multi-agent joint trajectories, including unobserved agents that may be revealed in the near future, depending on the robot's actions. Our predictive model is implemented using deep neural networks that map raw observations to future detection and pose trajectories and is learned entirely offline using a dataset of recorded observations (not ground-truth states). Once learned, our predictive model can be used for contingency planning over the potential existence, intentions, and positions of unobserved agents. We demonstrate the effectiveness of AVP on a set of autonomous driving environments inspired by real-world scenarios that require reasoning about the existence of other unobserved agents for safe and efficient driving. In these environments, AVP achieves expert-level closed-loop performance, while methods that do not reason about potential unobserved agents exhibit either overconfident or underconfident behavior.

Conservation strategies to protect biodiversity and support household livelihoods face numerous challenges. Across the tropics, efforts focus on balancing trade-offs in local communities near the borders of protected areas. Devolving rights and control over certain resources to communities is increasingly considered necessary, but decades of attempts have yielded limited success and few lessons on how such interventions could be successful in improving livelihoods. We investigated a key feature of household well-being, the experience of food insecurity, in villages across Tanzania's northern wildlife tourist circuit. Using a sample of 2,499 primarily livestock-keeping households we compared food insecurity in villages participating in the country's principal community-based conservation strategy with nearby control areas. We tested whether community-based projects could offset the central costs experienced by households near strictly protected areas (i.e. frequent human-wildlife conflict and restricted access to resources). We found substantial heterogeneity in outcomes associated with the presence of community-based conservation projects across multiple project sites. Although households in project villages experienced more frequent conflict with wildlife and received few provisioned benefits, there is evidence that these households may have been buffered to some degree against negative effects of wildlife conflict. We interpret our results in light of qualitative institutional factors that may explain various project outcomes. Tanzania, like many areas of conservation importance, contains threatened biodiversity alongside areas of extreme poverty. Our analyses highlight the need to examine more precisely the complex and locally specific mechanisms by which interventions do or do not benefit wildlife and local communities.

Predator control programmes are generally implemented in an attempt to increase prey population sizes. However, predator removal could prove harmful to prey populations that are regulated primarily by parasitic infections rather than by predation. We develop models for microparasitic and macroparasitic infection that specify the conditions where predator removal will (a) increase the incidence of parasitic infection, (b) reduce the number of healthy individuals in the prey population and (c) decrease the overall size of the prey population. In general, predator removal is more likely to be harmful when the parasite is highly virulent, macroparasites are highly aggregated in their prey, hosts are long-lived and the predators select infected prey.

LOX-1 is a multifunctional membrane receptor that binds and internalizes oxidized LDL (oxLDL). We tested the hypothesis that blockade of LOX-1 with an anti-LOX-1 antibody limits nephropathy in male rats with diabetes and dyslipidemia (ZS rats; [F.sub.1] hybrid product of Zucker fatty diabetic rats and spontaneous hypertensive heart failure rats). Lean ZS rats were controls, while untreated obese ZS (OM), ZS obese rats injected with nonspecific rabbit IgG (OM-IgG; 2 [micro]g intravenous injection given weekly), and obese ZS rats given anti-LOX-1 rabbit antibody (OM-Ab; 2 [micro]g intravenous injection given weekly) were the experimental groups. The rats were treated from 6 to 21 wk of age. All obese groups had severe dyslipidemia and hyperglycemia. Kidneys of obese rats expressed LOX-1 in capillaries and tubules, were larger, accumulated lipid, had intense oxidative stress, leukocyte infiltration, depressed mitochondrial enzyme level and function, and peritubular fibrosis (all P < 0.05 vs. lean ZS rats). Injections with LOX-1 antibody limited these abnormalities (P < 0.01 vs. data in OM or OM-1gG rats). In vitro, renal epithelial LOX-1 expression was verified in a cultured proximal tubule cell line. Our study indicates that anti-LOX-1 (vascular and epithelial) therapy may effectively reverse critical pathogenic elements of nephropathy in diabetes and dyslipidemia. renal failure; diabetic nephropathies; atherosclerosis

Anomalous inflammatory responses triggered by the metabolic syndrome cause renal injury. This discovery links renal lipid accumulation with lipotoxicity to inflammation and may explain the insidious fibrosis and cellular decay characteristic of nephropathy in the metabolic syndrome. However, it is not clear whether control of inflammation protects the kidney independently of lipid accumulation, which is a required step for lipotoxicity in hyperglycemia and dyslipidemia. We hypothesized that in rats with the metabolic syndrome, and overt nephropathy, treatment with mycophenolate mofetil (MMF; 10 mg* [kg.sup.-1]*[day.sup.-1] ip for 14 wk) would reduce the abnormal renal lipid depots and limit renal inflammation and injury. We studied groups of lean and obese [F.sub.1] hybrid Zucker fatty diabetic/spontaneous hypertensive heart failure (ZS) rats. MMF did not affect lean rats. In obese ZS rats, MMF did not change severe hyperglycemia or the higher kidney loads of unutilized lipid and peroxidation products. Nonetheless, MMF dramatically reduced diabetes/obesity-derived systemic and renal inflammation, limited renal size, hyperfiltration, and fibrosis. These data indicate that in rats, anti-inflammatory therapy presumably acting downstream, and independently of lipotoxicity, can effectively limit renal injury and fibrosis. diabetic nephropathies; lipid peroxidation

Ylang-ylang (Cananga odorata Hook.f. & Thoms.) is cultivated in many tropical areas of the world for the multiple applications of the essential oil extracted from its flowers. The aim of this work was to determine the concentrations of macro-nutrientes and micro-nutrients in the different ylang-ylang organs in two treatments, without fertilization and with commercial fertilization, based on a nutritional analysis of the soil of a production farm located in Chongón, Guayas, Ecuador. The concentrations of N, P and Mg were significantly higher in the treatment with fertilization (16.82; 2.96; 3.81 vs. 14.63; 2.39; 3.12 g/kg, respectively). Concerning micronutrients, in the treatment with fertilization, Mn, Cu and Mo concentrations were significantly higher (73.00; 13.50; 1.28 vs. 44.96; 9.08; 0.50 mg/kg), while Cl concentration was significantly lower (1692.58 vs. 3488.25 mg/kg). Significant differences were also found in nutrient concentration as a function of organs. The C. odorata N, P, K, Ca, Mg and S extraction is 30.83; 3.46; 12.87; 25.50; 4.85 and 3.35 kg/ha, respectively. Higher concentrations of N, Ca and K are suggested for this crop. These results contribute to the improvement of the quality of fertilization in the ylang-ylang cultivation.

An investigation of pulmonary and systemic arterial muscle contraction during hypoxia has provided evidence linking arterial contraction and myosin light chain (MLC20) phosphorylation. Experiments on isolated rat pulmonary and carotid strips revealed that tension development during hypoxia is correlated with MLC20 phosphorylation. MLC20 phosphorylaton was shown to modulate hypoxia-induced pulmonary arterial muscle contraction. In contrast, MLC20 dephosphorylation was shown to modulate hypoxia-induced systemic arterial muscle contraction.

Pulmonary vein contraction due to hypoxia was analyzed in rats, and venous and arterial reactions were contrasted. The venous single phase response was more powerful than the arterial distinctly biphasic response. The hypoxial reaction in pulmonary veins was unaffected by the absence of the endothelium, unlike the first phase in the arterial reaction. Pulmonary vascular inhibition of lung liquid accumulation is influenced by venous reactions of pulmonary circulation.

The secondary messenger in norepinephrine- (NE) and hypoxia-induced vasoconstriction of rat pulmonary artery is determined. Resultsreveal that NE-dependent vasoconstriction utilizes inositol trisphosphate (IP3)as a secondary messenger as the intracellular level of this compound doubled after NE administration. On the other hand, hypoxia-induced vasoconstriction does not utilize IP3 as a secondary messenger.

The participation of individual African lions, Panthera leo, during 64 communal hunts of four prey species was measured to quantify the extent to which lions cooperate and the factors affecting the degree of cooperation. The extent of individual participation in communal hunts varied significantly. Finite mixture models were used to determine the probability that each lion's behaviour belonged to each of three strategies: 'refraining' (non-participation in hunts), 'conforming' (active participation in groups in which all individuals behaved similarly) and 'pursuing' (active participation in groups where individual behaviour varies). Our analysis reveals two important trends. First, males refrain more and pursue less than females. Second, refraining during a group hunt is more common during hunts of prey that appear to be easier to capture: lions are more likely to refrain during hunts of wart hog, Phacochoerus aethiopicus, and less likely to refrain during hunts of zebra, Equus burchelli, and buffalo, Syncerus caffer. Of the alternatives considered, the data indicate that refraining is 'cheating' and that lions exhibiting this strategy are thus exploiting the hunting behaviour of their companions. These results are discussed in the framework of a recent game-theoretical model of cooperative hunting.

MAPK and PKC activity are not required for [H.sub.2][0.sub.2]-induced arterial muscle contraction. Am J Physiol Heart Circ Physiol 279: H1194-H1200, 2000.--[H.sub.2][0.sub.2]-induced pulmonary arterial smooth muscle (PASM) contractions are independent of [Ca.sup.2+] and myosin light chain phosphorylation. The purpose of this study was to determine whether mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK) 1 and ERK2, or protein kinase C (PKC) activation is required for [H.sub.2][0.sub.2]-induced contraction. Porcine PASM strips were stimulated with 1 mM [H.sub.2][0.sub.2], 120 mM KCl, or 10 [micro]M phorbol myristic acetate and freeze clamped at various times during the contractions. Changes in relative amounts of tyrosine/ threonine phosphorylated MAPK compared with total MAPK were measured. MAPK tyrosine phosphorylation levels increased in correlation with tension development. However, 50 [micro]M PD-98059, a MAPK/ERK kinase-MAPK kinase blocker, reduced MAPK phosphorylation below resting levels, even though the magnitude of the isometric tension development was unaltered. Freeze-clamped PASM strips were placed in a PKC activity assay buffer containing [sup.32]p and [CaCl.sub.2] to measure the total myelin basic protein phosphorylation. The data show that: 1) the time courses of PKC activity and force produced in response to [H.sub.2][0.sub.2] do not correlate, and 2) MAPK activation may be a concurrent event with, or a consequence of, tension development in response to a variety of agonists but is not responsible for contractions to [H.sub.2][0.sub.2], high [K.sup.+], or phorbol esters. reactive oxygen species; vasoconstriction; second messengers; mitogen-activated protein kinase; protein kinase C

[H.sub.2][O.sub.2] mediates [Ca.sup.2+]- and [MLC.sub.20] phosphorylation-independent contraction in intact and permeabilized vascular muscle. Am J Physiol Heart Circ Physiol 279: H1185-H1193, 2000.--One purpose of the current study was to establish whether vasoconstriction occurs in all vessel types in response to [H.sub.2][O.sub.2]. Isometric force was measured in pulmonary venous and arterial rings, and isobaric contractions were measured in mesenteric arteries and veins in response to [H.sub.2][O.sub.2]. A second purpose was to determine whether [H.sub.2][O.sub.2]-induced contraction is calcium independent. The addition of [H.sub.2][O.sub.2] to calcium-depleted (using the [Ca.sup.2+] ionophore ionomycin in zero calcium EGTA buffer) muscle caused contraction. Furthermore, permeabilized muscle contracted in response to [H.sub.2][O.sub.2] even in zero [Ca.sup.2+]. The final purpose was to determine whether the 20-kDa regulatory myosin light chain ([MLC.sub.20]) phosphorylation plays a role in [H.sub.2][O.sub.2]-induced contraction. Pulmonary arterial strips were freeze-clamped at various time points during [H.sub.2][O.sub.2]-induced contractions, and the relative amounts of phosphorylated [MLC.sub.20] were measured. [H.sub.2][O.sub.2] caused dose-dependent contractions that were independent of [MLC.sub.20] phosphorylation. ML-9, a myosin light chain kinase inhibitor, had no effect on the [H.sub.2][O.sub.2] contractile response. In conclusion, [H.sub.2][O.sub.2] induces [Ca.sup.2+]- and [MLC.sub.20] phosphorylation-independent contraction in pulmonary and systemic arterial and venous smooth muscle. reactive oxygen species; vasoconstriction; signal transduction; arterial smooth muscle; venous smooth muscle; myosin light chain