131 research outputs found
Laser Induced Selective Alignment of Water Spin Isomers
We consider laser alignment of ortho and para spin isomers of water molecules
by using strong and short off-resonance laser pulses. A single pulse is found
to create a distinct transient alignment and antialignment of the isomeric
species. We suggest selective alignment of one isomeric species (leaving the
other species randomly aligned) by a pair of two laser pulses.Comment: 6 pages, 4 figures, 3 table
Comparison of chemical characteristics of shoot, root and litter in three range species of Salsola rigida, Artemisia sieberi and Stipa barbata
Some chemical characteristics of root, shoot and litter of index species such as Salsola rigida, Artemisia
sieberi and Stipa barbata commonly used in rangeland development projects were evaluated and compared.
Chemical properties of soil under and between the above mentioned species were also studied. For this
purpose, vegetation types of Stipa barbata and Artemisia sieberi - Salsola rigida were selected in Zarand-eSaveh rangelands. Totally, 30 individuals of each species within each type were randomly selected for
shoot, root and litter sampling and chemical analyses. Also, values of N, P, K, C and C/N ratio were
measured in different parts of the species. Results showed that the highest and lowest C/N ratios were
related to Stipa barbata root and Artemisia sieberi shoots, respectively. N and P values of Stipa barbata litter
were the lowest while Artemisia sieberi and Salsola rigida shoots had the highest values of P and N,
respectively. Litter of Salsola rigida and shoot of Artemisia sieberi had the lowest and highest K, respectively.
C/N ratio of A. sieberi soil was lower than rest of the species
Controlling the sense of molecular rotation: classical vs quantum analysis
Recently, it was predicted theoretically and verified experimentally that a
pair of delayed and cross-polarized short laser pulses can create molecular
ensembles with a well defined sense of rotation (clockwise or
counterclockwise). Here we provide a comparative study of the classical and
quantum aspects of the underlying mechanism for linear molecules and for
symmetric tops, like benzene molecules, that were used for the first
experimental demonstration of the effect. Very good quantitative agreement is
found between the classical description of the process and the rigorous quantum
mechanical analysis at the relevant experimental conditions. Both approaches
predict the same optimal values for the delay between pulses and the angle
between them, and deliver the same magnitude of the induced oriented angular
momentum of the molecular ensemble. As expected, quantum and classical analysis
substantially deviate when the delay between pulses is comparable with the
period of quantum rotational revivals. However, time-averaged characteristics
of the excited molecular ensemble are equally good described by the these two
approaches. This is illustrated by calculating the anisotropic time-averaged
angular distribution of the double-pulse excited molecules, which reflects
persistent confinement of the molecular axes to the rotation plane defined by
two polarization vectors of the pulses.Comment: 27 pages, 9 figure
Detection of Echinococcus multilocularis in Carnivores in Razavi Khorasan Province, Iran Using Mitochondrial DNA
Echinococcus multilocularis causes alveolar echinococcosis, a serious zoonotic disease present in many areas of the world. The parasite is maintained in nature through a life cycle in which adult worms in the intestine of carnivores transmit infection to small mammals, predominantly rodents, via eggs in the feces. Humans may accidentally ingest eggs of E. multilocularis through contact with the definitive host or by direct ingestion of contaminated water or foods, causing development of a multivesicular cyst in the viscera, especially liver and lung. We found adult E. multilocularis in the intestine and/or eggs in feces of all wild carnivores examined and in some stray and domestic dogs in villages of Chenaran region, northeastern Iran. The life cycle of E. multilocularis is being maintained in this area by wild carnivores, and the local population and visitors are at risk of infection with alveolar echinococcosis. Intensive health initiatives for control of the parasite and diagnosis of this potentially fatal disease in humans, in this area of Iran, are needed
Digitalized transcranial electrical stimulation: A consensus statement
Objective: Although relatively costly and non-scalable, non-invasive neuromodulation interventions are treatment alternatives for neuropsychiatric disorders. The recent developments of highly-deployable transcranial electric stimulation (tES) systems, combined with mobile-Health technologies, could be incorporated in digital trials to overcome methodological barriers and increase equity of access. The study aims are to discuss the implementation of tES digital trials by performing a systematic scoping review and strategic process mapping, evaluate methodological aspects of tES digital trial designs, and provide Delphi-based recommendations for implementing digital trials using tES. Methods: We convened 61 highly-productive specialists and contacted 8 tES companies to assess 71 issues related to tES digitalization readiness, and processes, barriers, advantages, and opportunities for implementing tES digital trials. Delphi-based recommendations (>60% agreement) were provided. Results: The main strengths/opportunities of tES were: (i) non-pharmacological nature (92% of agreement), safety of these techniques (80%), affordability (88%), and potential scalability (78%). As for weaknesses/threats, we listed insufficient supervision (76%) and unclear regulatory status (69%). Many issues related to methodological biases did not reach consensus. Device appraisal showed moderate digitalization readiness, with high safety and potential for trial implementation, but low connectivity. Conclusions: Panelists recognized the potential of tES for scalability, generalizability, and leverage of digital trials processes; with no consensus about aspects regarding methodological biases. Significance: We further propose and discuss a conceptual framework for exploiting shared aspects between mobile-Health tES technologies with digital trials methodology to drive future efforts for digitizing tES trials
Recommended from our members
Global, regional, and national burden of low back pain, 1990–2020, its attributable risk factors, and projections to 2050: a systematic analysis of the Global Burden of Disease Study 2021
Population-level risks of alcohol consumption by amount, geography, age, sex, and year: a systematic analysis for the Global Burden of Disease Study 2020
Background The health risks associated with moderate alcohol consumption continue to be debated. Small amounts of alcohol might lower the risk of some health outcomes but increase the risk of others, suggesting that the overall risk depends, in part, on background disease rates, which vary by region, age, sex, and year. Methods For this analysis, we constructed burden-weighted dose–response relative risk curves across 22 health outcomes to estimate the theoretical minimum risk exposure level (TMREL) and non-drinker equivalence (NDE), the consumption level at which the health risk is equivalent to that of a non-drinker, using disease rates from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2020 for 21 regions, including 204 countries and territories, by 5-year age group, sex, and year for individuals aged 15–95 years and older from 1990 to 2020. Based on the NDE, we quantified the population consuming harmful amounts of alcohol. Findings The burden-weighted relative risk curves for alcohol use varied by region and age. Among individuals aged 15–39 years in 2020, the TMREL varied between 0 (95% uncertainty interval 0–0) and 0·603 (0·400–1·00) standard drinks per day, and the NDE varied between 0·002 (0–0) and 1·75 (0·698–4·30) standard drinks per day. Among individuals aged 40 years and older, the burden-weighted relative risk curve was J-shaped for all regions, with a 2020 TMREL that ranged from 0·114 (0–0·403) to 1·87 (0·500–3·30) standard drinks per day and an NDE that ranged between 0·193 (0–0·900) and 6·94 (3·40–8·30) standard drinks per day. Among individuals consuming harmful amounts of alcohol in 2020, 59·1% (54·3–65·4) were aged 15–39 years and 76·9% (73·0–81·3) were male. Interpretation There is strong evidence to support recommendations on alcohol consumption varying by age and location. Stronger interventions, particularly those tailored towards younger individuals, are needed to reduce the substantial global health loss attributable to alcohol. Funding Bill & Melinda Gates Foundation
- …