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31.
Glenn Varona 《Systemic Practice and Action Research》2012,25(3):209-222
Improving ethics and governance in policing is often considered an institutional function that police agencies do as ??expert?? institutions. Participation by other stakeholders may be welcome so long as police are able to control the processes and mechanisms of participation. This paper, based on research done with the Philippine National Police, argues that collaborative inquiry could be an effective critical systemic approach to participation by the wider society in police reform. This could enable both police and non-police stakeholders to work together towards mutual understanding and cooperation as equals towards better policing. This participatory approach is not meant to replace the institutional mechanisms that the police use for their own reform effort, but it is supposed to complement them. The research on which this paper is based was an attempt to design a model for collaborative inquiry at the local municipal level of policing in the Philippines, since the municipality is the lowest operational level for the Philippines?? police service. The results of that study suggest that it is possible to establish such a mechanism and make it work, in effect establishing a Close Knit Knowledge Organisation at the lowest level of operational policing. 相似文献
32.
A plasma protein marker for population genetic studies of the desert tortoise ( Xerobates agassizi )
Fifty-seven individual plasma samples from desert tortoises ( Xerobates agassizi ) representing 10 separate populations were analyzed by polyacrylamide gel electrophoresis using alkaline buffers. An albumin-like protein was found to be polymorphic for two electromorphs in northern populations inhabiting the Mohave Desert Province while Sonoran Desert populations to the south were monomorphic. The genetic divergence demonstrated in this survey is similar to earlier studies and provides evidence for the Colorado River as a potential barrier to gene flow among tortoise populations. These data suggest that tortoise plasma, examined by various electrophoretic methods, may provide a nondestructive means of determining the broad regional origin of desert tortoises. 相似文献
33.
Climate varied enormously over the most recent ice age--for example, large pulses of ice-rafted debris, originating mainly from the Labrador Sea, were deposited into the North Atlantic at roughly 7,000-year intervals, with global climatic implications. Here we show that ocean tides within the Labrador Sea were exceptionally large over the period spanning these huge, abrupt ice movements, which are known as Heinrich events. We propose that tides played a catalytic role in liberating iceberg armadas during that time. 相似文献
34.
Possemato R Marks KM Shaul YD Pacold ME Kim D Birsoy K Sethumadhavan S Woo HK Jang HG Jha AK Chen WW Barrett FG Stransky N Tsun ZY Cowley GS Barretina J Kalaany NY Hsu PP Ottina K Chan AM Yuan B Garraway LA Root DE Mino-Kenudson M Brachtel EF Driggers EM Sabatini DM 《Nature》2011,476(7360):346-350
Cancer cells adapt their metabolic processes to drive macromolecular biosynthesis for rapid cell growth and proliferation. RNA interference (RNAi)-based loss-of-function screening has proven powerful for the identification of new and interesting cancer targets, and recent studies have used this technology in vivo to identify novel tumour suppressor genes. Here we developed a method for identifying novel cancer targets via negative-selection RNAi screening using a human breast cancer xenograft model at an orthotopic site in the mouse. Using this method, we screened a set of metabolic genes associated with aggressive breast cancer and stemness to identify those required for in vivo tumorigenesis. Among the genes identified, phosphoglycerate dehydrogenase (PHGDH) is in a genomic region of recurrent copy number gain in breast cancer and PHGDH protein levels are elevated in 70% of oestrogen receptor (ER)-negative breast cancers. PHGDH catalyses the first step in the serine biosynthesis pathway, and breast cancer cells with high PHGDH expression have increased serine synthesis flux. Suppression of PHGDH in cell lines with elevated PHGDH expression, but not in those without, causes a strong decrease in cell proliferation and a reduction in serine synthesis. We find that PHGDH suppression does not affect intracellular serine levels, but causes a drop in the levels of α-ketoglutarate, another output of the pathway and a tricarboxylic acid (TCA) cycle intermediate. In cells with high PHGDH expression, the serine synthesis pathway contributes approximately 50% of the total anaplerotic flux of glutamine into the TCA cycle. These results reveal that certain breast cancers are dependent upon increased serine pathway flux caused by PHGDH overexpression and demonstrate the utility of in vivo negative-selection RNAi screens for finding potential anticancer targets. 相似文献
35.
Craig Groves Terry Frederick Glenn Frederick Eric Atkinson Melonie Atkinson Jay Shepherd Gregg Servheen 《西北部美国博物学家》2011,57(2)
From 1990 to 1992 we surveyed for Flammulated Owls ( Otus flammeolus ) in 3 areas in Idaho: Salmon National Forest (SNF), Payette National Forest and adjacent Hells Canyon National Recreation Area (PNF-HCNRA), and Nez Perce National Forest (NPNF). We also collected and summarized information on all historic and modern records of Flammulated Owls in Idaho. Flammulated Owls were detected on 65% of 68 routes (2-16 km in length) surveyed at densities ranging from 0.04 to 1.25 singing males/40 ha. Owls were detected on survey routes as early as 10 May and as late as 23 July. Mean percent canopy cover estimated at owl locations on the PNF-HCNRA and NPNF study sites ranged from 52% to 64%, while shrub cover ranged from 16% to 21% and ground cover was 39% to 49%. Our surveys and summary of distributional records indicated that Flammulated Owls occur throughout the montane forests of Idaho in old or mature stands of open ponderosa pine ( Pinus ponderosa ), Douglas-fir ( Pseudotsuga menziesii ), and stands co-dominated by those 2 species. Fire suppression and timber harvest activity in ponderosa pine forests represent 2 main threats to the species' future security in Idaho. More research on the effects of various silvicultural treatments on Flammulated Owl populations is warranted. 相似文献
36.
Nine species of fleas were collected incidental to a survey of rodents for molecular studies in Arizona, Colorado, New Mexico, Texas, and Utah, south of latitude 38° N. Three species were parasites of woodrats, Neotoma spp.: Orchopeas neotomae Augustson was confirmed for Texas, and the distribution patterns of O. agilis (Rothschild) and O. schisintus (Jordan) were more clearly defined. Four species were parasites of mice, Peromyscus spp.: Aetheca wagneri (Baker) was a new flea for P. gratus Merriam, the distribution of O. leucopus (Baker) was extended to far west Texas, Plusaetis sibynus (Jordan) was new for Utah and N. lepida , and the range of Stenoponia americana (Baker) was extended west of the Continental Divide in New Mexico. Other species included Foxella ignota (Baker) and Meringis dipodomys Kohls. 相似文献
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38.
Haiman CA Chen GK Blot WJ Strom SS Berndt SI Kittles RA Rybicki BA Isaacs WB Ingles SA Stanford JL Diver WR Witte JS Hsing AW Nemesure B Rebbeck TR Cooney KA Xu J Kibel AS Hu JJ John EM Gueye SM Watya S Signorello LB Hayes RB Wang Z Yeboah E Tettey Y Cai Q Kolb S Ostrander EA Zeigler-Johnson C Yamamura Y Neslund-Dudas C Haslag-Minoff J Wu W Thomas V Allen GO Murphy A Chang BL Zheng SL Leske MC Wu SY Ray AM Hennis AJ Thun MJ Carpten J Casey G Carter EN Duarte ER Xia LY Sheng X Wan P Pooler LC 《Nature genetics》2011,43(6):570-573
In search of common risk alleles for prostate cancer that could contribute to high rates of the disease in men of African ancestry, we conducted a genome-wide association study, with 1,047,986 SNP markers examined in 3,425 African-Americans with prostate cancer (cases) and 3,290 African-American male controls. We followed up the most significant 17 new associations from stage 1 in 1,844 cases and 3,269 controls of African ancestry. We identified a new risk variant on chromosome 17q21 (rs7210100, odds ratio per allele = 1.51, P = 3.4 × 10(-13)). The frequency of the risk allele is ~5% in men of African descent, whereas it is rare in other populations (<1%). Further studies are needed to investigate the biological contribution of this allele to prostate cancer risk. These findings emphasize the importance of conducting genome-wide association studies in diverse populations. 相似文献
39.
Mean monoterpene content of singleleaf pinyon ( Pinus monophylla [Torr.] Frem.) litter from stands growing on two soil series was 340 ± 310 ug/g air dry weight (adw). Individual monoterpene hydrocarbons suggested as potential allelopathic compounds occur in extremely small amounts, 0.5-1.10 ug/g adw. Mineral soils contained 50 times less total terpene, 6.6 ug/g ± 4.8 adw, than the litter immediately above. Results suggest that allelopathic effects would more likely occur in litter than mineral soil. These findings are substantiated by previous reports of decreased emergence and growth of herbaceous species in pinyon litter but not mineral soil. 相似文献
40.
Thomas RK Baker AC Debiasi RM Winckler W Laframboise T Lin WM Wang M Feng W Zander T MacConaill L Macconnaill LE Lee JC Nicoletti R Hatton C Goyette M Girard L Majmudar K Ziaugra L Wong KK Gabriel S Beroukhim R Peyton M Barretina J Dutt A Emery C Greulich H Shah K Sasaki H Gazdar A Minna J Armstrong SA Mellinghoff IK Hodi FS Dranoff G Mischel PS Cloughesy TF Nelson SF Liau LM Mertz K Rubin MA Moch H Loda M Catalona W Fletcher J Signoretti S Kaye F Anderson KC Demetri GD Dummer R Wagner S 《Nature genetics》2007,39(3):347-351
Systematic efforts are underway to decipher the genetic changes associated with tumor initiation and progression. However, widespread clinical application of this information is hampered by an inability to identify critical genetic events across the spectrum of human tumors with adequate sensitivity and scalability. Here, we have adapted high-throughput genotyping to query 238 known oncogene mutations across 1,000 human tumor samples. This approach established robust mutation distributions spanning 17 cancer types. Of 17 oncogenes analyzed, we found 14 to be mutated at least once, and 298 (30%) samples carried at least one mutation. Moreover, we identified previously unrecognized oncogene mutations in several tumor types and observed an unexpectedly high number of co-occurring mutations. These results offer a new dimension in tumor genetics, where mutations involving multiple cancer genes may be interrogated simultaneously and in 'real time' to guide cancer classification and rational therapeutic intervention. 相似文献