We compute the full-color two-loop five-gluon amplitude for the all-plus helicity configuration. In order to achieve this, we calculate the required master integrals for all permutations of the ...external legs, in the physical scattering region. We verify the expected divergence structure of the amplitude and extract the finite hard function. We further validate our result by checking the factorization properties in the collinear limit. Our result is fully analytic and valid in the physical scattering region. We express it in a compact form containing logarithms, dilogarithms, and rational functions.
We present a computer library for the numerical evaluation of colour-ordered n-gluon amplitudes at one-loop order in pure Yang–Mills theory. The library uses the recently developed technique of ...generalised unitarity. Running in double precision the library yields reliable results for up to 14 gluons with only a small fraction of events requiring a re-evaluation using extended floating point arithmetic. We believe that the library presented here provides an important contribution to future LHC phenomenology. The program may also prove useful in cross checking results obtained by other methods. In addition, the code provides a sample implementation which may serve as a starting point for further developments.
Program title:NGluon
Catalogue identifier: AEIZ_v1_0
Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEIZ_v1_0.html
Program obtainable from: CPC Program Library, Queenʼs University, Belfast, N. Ireland
Licensing provisions: GNU Public License
No. of lines in distributed program, including test data, etc.: 30 677
No. of bytes in distributed program, including test data, etc.: 334 896
Distribution format: tar.gz
Programming language: C++
Computer: Any computer platform supported by the GNU compiler suite.
Operating system: No specific requirements – tested on Scientific Linux 5.2.
RAM: Depending on the complexity, for realistic applications like 10 gluon production in double precision below 10 MB.
Classification: 11.5
External routines: QCDLoop (http://qcdloop.fnal.gov/), qd (http://crd.lbl.gov/~dhbailey/mpdist/)
Nature of problem: Evaluation of next-to-leading order corrections for gluon scattering amplitudes in pure gauge theory.
Solution method: Purely numerical approach based on tree amplitudes obtained via Berends–Giele recursion combined with unitarity method.
Restrictions: Running in double precision the number of gluons should not exceed 14.
Running time: Depending on the number of external gluons between less than a millisecond (4 gluons) up to a 1 s (14 gluons) per phase space point.
► We present a c++ code computing one-loop multi-gluon amplitudes in Yang–Mills. ► We use newly developed generalised unitarity methods for a fast implementation. ► An arbitrary number of gluons can be computed using multiple precision. ► Results are numerically stable in double precision for <14 gluons.
During the Mid-Pleistocene Transition (MPT; 1,200–800 kya), Earth’s orbitally paced ice age cycles intensified, lengthened from ∼40,000 (∼40 ky) to ∼100 ky, and became distinctly asymmetrical. ...Testing hypotheses that implicate changing atmospheric CO₂ levels as a driver of the MPT has proven difficult with available observations. Here, we use orbitally resolved, boron isotope CO₂ data to show that the glacial to interglacial CO₂ difference increased from ∼43 to ∼75 μatm across the MPT, mainly because of lower glacial CO₂ levels. Through carbon cycle modeling, we attribute this decline primarily to the initiation of substantive dust-borne iron fertilization of the Southern Ocean during peak glacial stages. We also observe a twofold steepening of the relationship between sea level and CO₂-related climate forcing that is suggestive of a change in the dynamics that govern ice sheet stability, such as that expected from the removal of subglacial regolith or interhemispheric ice sheet phase-locking. We argue that neither ice sheet dynamics nor CO₂ change in isolation can explain the MPT. Instead, we infer that the MPT was initiated by a change in ice sheet dynamics and that longer and deeper post-MPT ice ages were sustained by carbon cycle feedbacks related to dust fertilization of the Southern Ocean as a consequence of larger ice sheets.
Prevention of psychosis has become a major objective of modern clinical psychiatry. An increasing number of new services have been established in Europe and in the world. The OASIS team has become an ...established model where clinical practice and research are fully integrated in the field of preventative interventions in psychosis.
Comprehensive analysis of different clinical and service measures describing the 2001–2011 implementation of the OASIS team.
Over the last decade, the OASIS team has received a total of 1102 referrals, mostly young males from ethnic minorities. After the assessment, 35% were diagnosed with an At Risk Mental State (ARMS) while 32% were already psychotic. Within the ARMS, 70% met the inclusion criteria for the attenuated psychotic symptoms subgroup, 1% met the inclusion criteria for the genetic deterioration syndrome, 9% met inclusion criteria for a brief and self-limited intermittent psychotic episode and the others met inclusion criteria for more than one subgroup. Most of them had at least one comorbid diagnosis, mainly relating to anxiety and depressive domains. The majority of the OASIS clients received cognitive behavioural therapy alone or in combination with antidepressants/antipsychotics. Over the 2-year follow-up time, 44 subjects (15.2%) developed a frank psychotic episode.
The OASIS service represents one of the largest and most established prodromal services in the world. The burden of research evidence and the translational impact produced on the clinical practice support the OASIS as a model for the development of similar services.
Coccolithophores and other haptophyte algae acquire the carbon required for metabolic processes from the water in which they live. Whether carbon is actively moved across the cell membrane via a ...carbon concentrating mechanism, or passively through diffusion, is important for haptophyte biochemistry. The possible utilization of carbon concentrating mechanisms also has the potential to over-print one proxy method by which ancient atmospheric CO2 concentration is reconstructed using alkenone isotopes. Here I show that carbon concentrating mechanisms are likely used when aqueous carbon dioxide concentrations are below 7 µmol L−1. I compile published alkenone-based CO2 reconstructions from multiple sites over the Pleistocene and recalculate them using a common methodology, which allows comparison to be made with ice core CO2 records. Interrogating these records reveals that the relationship between proxy CO2 and ice core CO2 breaks down when local aqueous CO2 concentration falls below 7 µmol L−1. The recognition of this threshold explains why many alkenone-based CO2 records fail to accurately replicate ice core CO2 records, and it suggests the alkenone proxy is likely robust for much of the Cenozoic when this threshold was unlikely to be reached in much of the global ocean.
Management of Liver Trauma Badger, S. A.; Barclay, R.; Campbell, P. ...
World journal of surgery,
December 2009, Letnik:
33, Številka:
12
Journal Article
Recenzirano
Background
Blunt and penetrating liver trauma is common and often presents major diagnostic and management problems.
Methods
A literature review was undertaken to determine the current consensus on ...investigation and management strategies.
Results
The liver is the most frequently injured organ following abdominal trauma. Immediate assessment with ultrasound has replaced diagnostic peritoneal lavage in the resuscitation room, but computerised tomography remains the gold standard investigation. Nonoperative management is preferred in stable patients but laparotomy is indicated in unstable patients. Damage control techniques such as perihepatic packing, hepatotomy plus direct suture, and resectional debridement are recommended. Major complex surgical procedures such as anatomical resection or atriocaval shunting are now thought to be redundant in the emergency setting. Packing is also recommended for the inexperienced surgeon to allow control and stabilisation prior to transfer to a tertiary centre. Interventional radiological techniques are becoming more widely used, particularly in patients who are being managed nonoperatively or have been stabilised by perihepatic packing.
Conclusions
Management of liver injuries has evolved significantly throughout the last two decades. In the absence of other abdominal injuries, operative management can usually be avoided. Patients with more complex injuries or subsequent complications should be transferred to a specialist centre to optimise final outcome.
Objective/Background Many associations between abdominal aortic aneurysm (AAA) and genetic polymorphisms have been reported. It is unclear which are genuine and which may be caused by type 1 errors, ...biases, and flexible study design. The objectives of the study were to identify associations supported by current evidence and to investigate the effect of study design on reporting associations. Methods Data sources were MEDLINE, Embase, and Web of Science. Reports were dual-reviewed for relevance and inclusion against predefined criteria (studies of genetic polymorphisms and AAA risk). Study characteristics and data were extracted using an agreed tool and reports assessed for quality. Heterogeneity was assessed using I 2 and fixed- and random-effects meta-analyses were conducted for variants that were reported at least twice, if any had reported an association. Strength of evidence was assessed using a standard guideline. Results Searches identified 467 unique articles, of which 97 were included. Of 97 studies, 63 reported at least one association. Of 92 studies that conducted multiple tests, only 27% corrected their analyses. In total, 263 genes were investigated, and associations were reported in polymorphisms in 87 genes. Associations in CDKN2BAS , SORT1 , LRP1 , IL6R , MMP3 , AGTR1 , ACE , and APOA1 were supported by meta-analyses. Conclusion Uncorrected multiple testing and flexible study design (particularly testing many inheritance models and subgroups, and failure to check for Hardy–Weinberg equilibrium) contributed to apparently false associations being reported. Heterogeneity, possibly due to the case mix, geographical, temporal, and environmental variation between different studies, was evident. Polymorphisms in nine genes had strong or moderate support on the basis of the literature at this time. Suggestions are made for improving AAA genetics study design and conduct.
Background
People with intellectual disabilities (ID) die on an average 20 years earlier to the general population. They have higher rates of multimorbidity and polypharmacy. Around 25% of people ...with ID report chronic constipation. The England Learning Disabilities Mortality Review found that nearly 25% of deaths identified constipation as a long‐term health problem. However, the likely risk factors for constipation related harm are poorly enumerated. We sought to identify possible specific high‐risk factors by examining the clinical characteristics of people with ID admitted to hospital with constipation.
Methods
Data of people with ID admitted with constipation in two general hospitals covering a population of 1.3 million from 2017 to 2022 were reported using the STROBE guideline for cohort studies. Collected data included age, gender, intellectual disability severity, recorded medication, presenting complaint and co‐morbidities. The medication anticholinergic burden was calculated using the anticholinergic burden scale. Continuous variables were summarised by mean and standard deviation if normally distributed, with categorical variables summarised by the number and percentage in each category.
Results
Of 46 admissions (males 52%), 57% had moderate to profound ID, 37% had epilepsy, 41% prescribed antiseizure medication (ASM) and 45% were on laxatives. Average age was 46 years. The anticholinergic burden score mean was 2.3 and median, one.
Conclusions
We can hypothesise that people with more severe ID, suffering from epilepsy and on ASM may be more at risk of developing severe constipation. Some admissions may be avoided with earlier use of laxatives in the community.
Objective
Improving antimicrobial stewardship in the livestock sector requires an understanding of the motivations for antimicrobial use and the quantities consumed. However,detailed information on ...antimicrobial use in livestock sectors is lacking. This cross‐sectional study aimed to better understand antimicrobial use in the beef feedlot sector in Australia.
Design
A self‐administered questionnaire asking about antimicrobial use and reasons for use was designed and mailed to beef feedlot operators in Australia. Respondents were asked to report the percentage of animals treated, purpose of use, and disease conditions targeted for 26antimicrobial agents.
Results
In total, 83 of 517 (16.1%) beef feedlot operators completed the survey. Monensin (61.0%of respondents) and virginiamycin (19.5%of respondents) were the most commonly reported in‐feed antimicrobials. In‐feed antimicrobial agents were most frequently used by respondents for treatment of gastrointestinal diseases (52.8%). Antimicrobials were used for growth promotion by 42.1% of respondents, with most (85.7%) reporting the use of ionophores(a group of compounds not used in human medicine). Short‐acting penicillin(69.1%), short‐acting oxytetracycline, and tulathromycin (both 57.3%) werethe most common injectable antimicrobial agents used. Injectable antimicrobials were most frequently used to treat respiratory (72.3%) and musculoskeletal (67.5%) conditions.
Conclusion
Overall,the use of antimicrobials was appropriate for the purpose indicated, and there was a strong preference for drugs of low‐importance in human medicine. The data described here stand to be a strong influence on the implementation of an antimicrobial stewardship program in the sector.
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