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One of the most surprising developments in Mexico's transition to democracy is the outbreak of criminal wars and large-scale criminal violence. Why did Mexican drug cartels go to war as the country transitioned away from one-party rule? And why have criminal wars proliferated as democracy has consolidated and elections have become more competitive subnationally? In Votes, Drugs, and Violence, Guillermo Trejo and Sandra Ley develop a political theory of criminal violence in weak democracies that elucidates how democratic politics and the fragmentation of power fundamentally shape cartels' incentives for war and peace. Drawing on in-depth case studies and statistical analysis spanning more than two decades and multiple levels of government, Trejo and Ley show that electoral competition and partisan conflict were key drivers of the outbreak of Mexico's crime wars, the intensification of violence, and the expansion of war and violence to the spheres of local politics and civil society.
Previous research on art therapy (AT) in cognitive aging has been lacking. AT can potentially engender significant cognitive gains, due to its rigorous cognitive involvement, making it useful to tackle age-related cognitive decline. Along with these cognitive gains, associated neuroplastic changes are hypothesized to arise from AT as well. The current intervention examined the effects of an AT intervention on cognitive outcomes and cortical thickness (CT) among participants with mild cognitive impairment.
Participants were assigned to AT (n = 22) and an active control group (n = 27). In both, weekly 45-min sessions were carried out across 3 months. Cognitive assessments and structural magnetic resonance imaging scans were carried out at baseline and 3-month follow-up. Whole brain analyses on CT were carried out. Cognitive outcomes were analyzed using hierarchical linear models.
Significant gains in immediate memory and working memory span were observed in the AT group, relative to the control group. Significantly increased CT in the AT group, relative to controls, was observed in a right middle frontal gyrus (MFG) cluster. Furthermore, CT changes in this cluster were significantly and positively correlated with changes in immediate memory.
These findings highlighted the role of MFG neuroplasticity in enhancing certain cognitive functions in AT. AT is a neuroplastic intervention capable of engendering significant cognitive gains and associated cortical changes in the context of age-related cognitive decline, even when executed as a low-intensity intervention across 3 months. Given the preliminary nature of these findings, future larger sampled studies are needed.
Which more importantly contributes to who we are and how we behave, biological influences or socio-cultural–environmental influences? This question reflects the essence of the “nature–nurture debate,” as traditionally defined. This debate and its appropriate resolution have important implications. At the same time, the nature–nurture debate is not profitably framed in this traditional way. The traditional framing implicitly assumes that “biological” and “environmental” causes – “nature” and “nurture” – constitute separable causes, as, say, pieces of a pie can be sliced apart and separated. In fact, they are not separable. To understand the effects of “nurture,” one must understand outcomes of “nature.” Within a reframing of the nature–nurture debate, one can ask a number of questions about the roles that nature and nurture play. We describe these questions. And we discuss some implications for understanding the sexes and, specifically, women.
The implementation effect of the 24-hour Supervise-Correct-Improve (SCI) supervision model was investigated in COVID-19 isolation ward in putting on and taking off process of personal protective equipment. As shown in results, the error rate of taking off process was significantly reduced (P < 0.001) by applying the 24h “SCI” mode. Staffs over 40 years old and workers were more likely to make mistakes. Through uninterrupted supervision and protection, application of this mode is proved to be effective.
The loggerhead turtle (Caretta caretta) is a circumglobal species and is listed as vulnerable globally. The North Pacific population nests in Japan and migrates to the Central North Pacific and Pacific coast of North America to feed. In the Mexican Pacific, records of loggerhead presence are largely restricted to the Gulf of Ulloa along the Baja California Peninsula, where very high fisheries by-catch mortality has been reported. Records of loggerhead turtles within the Sea of Cortez also known as the Gulf of California (GC) exist; however, their ecology in this region is poorly understood. We used satellite tracking and an environmental variable analysis (chlorophyll-a (Chl-a) and sea surface temperature (SST)) to determine movements and habitat use of five juvenile loggerhead turtles ranging in straight carapace length from 62.7–68.3 cm (mean: 66.7 ± 2.3 cm). Satellite tracking durations ranged from 73–293 days (mean: 149 ± 62.5 days), transmissions per turtle from 14–1006 (mean: 462 ± 379.5 transmissions) and total travel distance from 1237–5222 km (mean: 3118 ± 1490.7 km). We used travel rate analyses to identify five foraging areas in the GC, which occurred mainly in waters from 10–80 m deep, with mean Chl-a concentrations ranging from 0.28–13.14 mg m−3 and SST ranging from 27.8–34.4°C. This is the first study to describe loggerhead movements in the Gulf of California and our data suggest that loggerhead foraging movements are performed in areas with eutrophic levels of Chl-a.
This study investigated the influence of berberine (BBR) supplementation in normal and high lipid diets on lipid metabolism and accumulation in black sea bream (Acanthopagrus schlegelii). Berberine was supplemented at 50 mg/kg to control (Con, 11.1% crude lipid) and high lipid (HL, 20.2% crude lipid) diets and named as ConB and HLB, respectively. After the 8-week feeding trial, fish body length and specific growth rate were significantly reduced by high lipid diets (P < 0.05). Muscle and whole-body crude lipid contents were significantly influenced by both BBR supplementation and dietary lipid level. Fish fed HLB diet had significantly lower serum triglyceride, low-density lipoprotein cholesterol contents, and alanine aminotransferase activity compared with the HL group. The HL group presented vast lipid accumulation in the liver, and hypertrophied hepatocytes along with large lipid droplets, and translocation of nuclear to the cell periphery. These abnormalities in black sea bream were alleviated in the HLB group. Berberine supplementation in high lipid diet significantly downregulated the hepatic expression levels of accα, srebp-1, 6pgd, g6pd and pparγ, whereas the lpl, hsl, and cpt1a expression levels were significantly upregulated. However, the expression levels of these genes showed opposite trends in muscle (except for pparγ). In conclusion, dietary BBR supplementation in high lipid diet reduced hepatic lipid accumulation by downregulating lipogenesis gene expression and upregulating lipolysis gene expression, and it increased muscle lipid contents with opposite trends of the mechanism observed in the liver.
Three-dimensional flow fields of a rectangular synthetic jet with aspect ratio of 3 and its interaction with a laminar cross-flow are measured using time-resolved tomographic particle image velocimetry. The synthetic-jet to free-stream velocity ratio is fixed at 1, and two orifice orientations, normal to (spanwise configuration) and aligned with (streamwise configuration) the cross-flow direction, respectively, are investigated. The flow scenarios are composed of a tilted vortex ring, a secondary trailing vortex and a tertiary near-wall vortex. Compared to previous results for circular cases, the legs of the trailing structures are found to be jointed in the spanwise direction by two shear-layer vortices at different wall-normal heights. In addition, the near-wall vortex is a crescent-shaped spanwise vortex. For the first time, as the peculiar process of non-circular vortex rings in quiescent condition, axis switching is validated to exist in the cross-flow. Associated with axis switching, the spanwise case exhibits interaction between the leeward vortex of the vortex ring and the downstream shear-layer vortex, which causes slower penetration and recovery of vortex ring tilting, but faster jet transition. Furthermore, the trailing structures and vortex ring are weakened, leading to lower peaks of the velocity deficit and overshoot in the jet region than those for the streamwise case. On the other hand, the spanwise case can induce a stronger near-wall vortex, which transfers more momentum and initial disturbance into the boundary layer. Consequently, the spanwise case yields larger velocity gradient and velocity fluctuation peak inside the boundary layer with a lower shape factor, suggesting greater efficiency of promoting boundary-layer transition.
A 6-week growth trial was conducted to evaluate the influences of dietary valine (Val) levels on growth, protein utilization, immunity, antioxidant status and gut micromorphology of juvenile hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂). Seven isoenergetic (340 kcal per 100 g of dry matter), isoproteic (49.3% of dry matter) and isolipidic (7% of dry matter) diets were formulated to contain graded Val levels (1.21, 1.32, 1.45, 1.58, 1.69, 1.82 and 1.94%, dry-matter basis). Each experimental diet was hand-fed to triplicate groups of 12 hybrid grouper juveniles (average initial body weight: 10.8 ± 0.01 g/fish) which were randomly distributed into 21 glass tanks (L 60 cm × W 45 cm × H 50 cm) connected to mechanical and biological water filters as a recycling system. Results showed that weight gain percentage (WG%), protein productive value (PPV), protein efficiency ratio (PER), and feed efficiency (FE) were increased as dietary Val level increased, reaching a peak value at 1.58% dietary Val, and thereafter, these four parameters declined as dietary Val levels continued to increase. Fish fed 1.58% dietary Val had lower daily feed intake (DFI) than fish fed other dietary Val levels. The quadratic regression analysis of WG%, PPV, PER and FE against dietary Val levels indicated that the optimum dietary Val requirement for hybrid grouper was estimated to be 1.56, 1.61, 1.61 and 1.60%, respectively. Gut micromorphology was significantly influenced by dietary Val levels. Expression of growth hormone (GH) in pituitary, insulin like growth factor 1 (IGF-1), target of rapamycin (TOR) and S6 kinase1 (S6K1) in liver was significantly affected by dietary Val levels, with the highest values exhibited in fish fed 1.58% dietary Val. Fish fed 1.21% dietary Val had lower protein level of S6K1 in liver than fish fed the other dietary Val levels. In serum, fish fed 1.58% dietary Val had higher superoxide dismutase (SOD), catalase (CAT), lysozyme (LZM) activities and immunoglobulin M (IgM) concentrations than fish fed other dietary Val levels. Fish fed 1.58% dietary Val had higher expression of NF-E2-related factor 2 (Nrf2) in head kidney than fish fed other dietary Val levels, and Kelch-like-ECH-associated protein 1 (Keap1) showed an opposite tendency of variations as Nrf2. Generally, the optimum dietary Val requirement for maximal growth of hybrid grouper was estimated to be 1.56% of dry matter, corresponding to 3.16% of dietary protein, and dietary Val levels affected growth, protein utilization, immunity and antioxidant status in hybrid grouper.
This study investigated the effect of Bacillus subtilis DSM 29784 (Ba) and enzymes (xylanase and β-glucanases; Enz), alone or in combination (BE) as antibiotic replacements, on the growth performance, digestive enzyme activity, immune response, and intestinal barrier of broiler chickens. In total, 1200 1-d-old broilers were randomly assigned to five dietary treatments, each with six replicate pens of 40 birds for 63 d as follows: A) basal diet (control), supplemented with B) 1×109 colony-forming units (cfu)/kg Ba, C) 300 mg/kg Enz, D) 1×109 cfu/kg Ba and 300 mg/kg Enz, and E) 250 mg/kg enramycin (ER). Ba, Enz, and BE, similar to ER, decreased the feed conversion rate, maintained intestinal integrity with a higher villus height-to-crypt depth ratio, and increased the numbers of goblet cells. The BE group exhibited higher expression of claudin-1 and Mucin-2 than the other four groups. BE supplementation significantly increased the α-diversity and β-diversity of the intestinal microbiota and markedly enhanced lipase activity in the duodenal mucosa. Serum endotoxin was significantly decreased in the BE group. Compared to those in the control group, increased superoxide dismutase and glutathione peroxidase activities were observed in the jejunal mucosa of Ba and BE groups, respectively. In conclusion, the results suggested that dietary treatment with Ba, Enz, or BE has beneficial effects on growth performance and anti-oxidative capacity, and BE had better effects than Ba or Enz alone on digestive enzyme activity and the intestinal microbiota. Ba or Enz could be used as an alternative to antibiotics for broiler chickens.
Integrating LiMn2O4(LMO) and different carbon materials to build a mixed cathode system can provide fast transport channels to improve the conduction of both electrons and ions. In this paper, our work studied in situ low-temperature hydrothermal synthesis of LMO nanocomposites based on graphene oxide (GO)/carbon nanotubes (CNTs) hydrogel. Compared with the pure LMO nanoparticles, GO/CNTs/LMO (GCLMO) composites greatly improved electrochemical performance in specific capacity, cycle performance and rate ability. The electrochemical test results showed that the specific capacitance of GCLMO nanocomposites reached 396 F/g at the current density of 0.5 A/g, which was much higher than 221 F/g of pure LMO. Even at the current density of 10 A/g, the specific capacitance was still as high as 309 F/g. Besides, after 2000 cycles, the specific capacitance retention of the composite was 93%. Electrochemical data showed that GCLMO composite is an ideal cathode material for supercapacitors.
A 2-year fertilization experiment was conducted to study the effect of different ratios of organic (pig) manure on wheat yield and nitrogen use efficiency (NUE). The four treatments were no nitrogen (N) (CK); 100% chemical fertilizer N (urea; T1); 70% chemical fertilizer N + 30% organic manure N (T2) and 50% chemical fertilizer N + 50% organic manure N (T3), with the same amount of applied nitrogen (120 kg/ha). The results showed the maximum grain yield (3049 kg/ha), crop nitrogen uptake (216 kg/ha), NUE (65.4%) and accumulated nitrate nitrogen (NO3−-N in 0–200 cm, 142 kg/ha) were observed in the T1 among all treatments in the first year. However, the largest grain yield (5074 kg/ha), crop nitrogen uptake (244 kg/ha) and NUE (82.5%) were under T2 treatment in the second year. Furthermore, T2 had the maximum NO3−-N content in 0–100 cm layer (116 kg/ha), especially 0–40 cm layer, and the lowest NO3−-N content in 100–200 cm (58.8 kg/ha). However, 50% organic manure N in T3 increased apparent nitrogen loss by 39.0% compared to that in T2. Therefore, 30% organic manure N application was more conducive for enhancing wheat yield and NUE and promoting environmental safety after 1-year fertilization time.
The accuracy of sea-ice motion products provided by the National Snow and Ice Data Center (NSIDC) and the Ocean and Sea Ice Satellite Application Facility (OSI-SAF) was validated with data collected by ice drifters that were deployed in the western Arctic Ocean in 2014 and 2016. Data from both NSIDC and OSI-SAF products exhibited statistically significant (p < 0.001) correlation with drifter data. The OSI-SAF product tended to overestimate ice speed, while underestimation was demonstrated for the NSIDC product, especially for the melt season and the marginal ice zone. Monthly Lagrangian trajectories of ice floes were reconstructed using the products. Larger spatial variability in the deviation between NSIDC and drifter trajectories was observed than that of OSI-SAF, and seasonal variability in the deviation for NSIDC was observed. Furthermore, trajectories reconstructed using the NSIDC product were sensitive to variations in sea-ice concentration. The feasibility of using remote-sensing products to characterize sea-ice deformation was assessed by evaluating the distance between two arbitrary positions as estimated by the products. Compared with the OSI-SAF product, relative errors are lower (<11.6%), and spatial-temporal resolutions are higher in the NSIDC product, which makes it more suitable for estimating sea-ice deformation.
The evolution of melt ponds on Arctic sea ice in summer is one of the main factors that affect sea-ice albedo and hence the polar climate system. Due to the different spectral properties of open water, melt pond and sea ice, the melt pond fraction (MPF) can be retrieved using a fully constrained least-squares algorithm, which shows a high accuracy with root mean square error ~0.06 based on the validation experiment using WorldView-2 image. In this study, the evolution of ponds on first-year and multiyear ice in the Canadian Arctic Archipelago was compared based on Sentinel-2 and Landsat 8 images. The relationships of pond coverage with air temperature and albedo were analysed. The results show that the pond coverage on first-year ice changed dramatically with seasonal maximum of 54%, whereas that on multiyear ice changed relatively flat with only 30% during the entire melting period. During the stage of pond formation, the ponds expanded rapidly when the temperature increased to over 0°C for three consecutive days. Sea-ice albedo shows a significantly negative correlation (R = −1) with the MPF in melt season and increases gradually with the refreezing of ponds and sea ice.