1,762 research outputs found
Time-dependent angularly averaged inverse transport
This paper concerns the reconstruction of the absorption and scattering
parameters in a time-dependent linear transport equation from knowledge of
angularly averaged measurements performed at the boundary of a domain of
interest. We show that the absorption coefficient and the spatial component of
the scattering coefficient are uniquely determined by such measurements. We
obtain stability results on the reconstruction of the absorption and scattering
parameters with respect to the measured albedo operator. The stability results
are obtained by a precise decomposition of the measurements into components
with different singular behavior in the time domain
A Unified Treatment of the Characters of SU(2) and SU(1,1)
The character problems of SU(2) and SU(1,1) are reexamined from the
standpoint of a physicist by employing the Hilbert space method which is shown
to yield a completely unified treatment for SU(2) and the discrete series of
representations of SU(1,1). For both the groups the problem is reduced to the
evaluation of an integral which is invariant under rotation for SU(2) and
Lorentz transformation for SU(1,1). The integrals are accordingly evaluated by
applying a rotation to a unit position vector in SU(2) and a Lorentz
transformation to a unit SO(2,1) vector which is time-like for the elliptic
elements and space-like for the hyperbolic elements in SU(1,1). The details of
the procedure for the principal series of representations of SU(1,1) differ
substantially from those of the discrete series.Comment: 31 pages, RevTeX, typos corrected. To be published in Journal of
Mathematical Physic
Coherent radiation by molecular magnets
The possibility of coherent radiation by molecular magnets is investigated.
It is shown that to realize the coherent radiation, it is necessary to couple
the considered sample to a resonant electric circuit. A theory for describing
this phenomenon is developed, based on a realistic microscopic Hamiltonian,
including the Zeeman terms, single-site anisotropy, and dipole interactions.
The role of hyperfine interactions between molecular and nuclear spins is
studied. Numerical solutions of the spin evolution equations are presented.Comment: Latex file, 11 pages, 3 figure
Radiological study on mandibular ramus asymmetry in young population
Background: The aim of this study was to estimate the prevalence of ramus asymmetries related to age and gender in a young population and the influence of growth spurt on ramus asymmetry.
Materials and methods: The study consisted of 776 panoramic radiographs of individuals aged 9 to 21 years (335 males and 441 females). Individuals were divided into two groups with respect of linear growth spurt as age 12 in females and age 14 in males. The first group consisted of females aged between 9 and 11 and males between 9 and 13. The second group consisted of females aged between 12 and 21 and males between 14 and 21. Bilateral ramus heights on each radiograph were measured. A panoramic software programme was used to measure the ramus heights. Quantitative data was tested by Student’s t test. Qualitative data was tested by χ2 test. The intraclass correlation coefficient was calculated for the magnitude error of the measurement.
Results: The mean of ramus asymmetry was found to be 2.90% ± 2.58%. Significant differences between the right and left ramus height ratios were observed (p < 0.01). There was a high prevalence (10.8%) of ramus asymmetry, which did not correlate with the age and gender of the patients.
Conclusions: This study revealed a high prevalence of ramus asymmetry in 9–21- -year-old population. Within the limitations of this study, it can be concluded that ramus asymmetry should be carefully evaluated in all ages for the potential relation with temporomandibular dysfunctions and also for orthodontic anomalies
Patient and family engagement in incident investigations: exploring hospital manager and incident investigators’ experiences and challenges
Objective: There is growing recognition among health care providers and policy makers that when things go wrong, the patient or their families should be heard and participate in the incident investigation process. This paper explores how Dutch hospitals organize patient or family engagement in incident investigations, maps out incident investigators’ experiences of involving patients or their families in incident investigations and identifies the challenges encountered. Methods: Semi-structured interviews were conducted with managers and incident investigators in 13 Dutch hospitals. Study participants (n = 18) were asked about the incident investigation routines and their experiences of involving affected patients or family members. Interview transcripts were coded and analysed using thematic content analysis. Results: Our findings reveal that patient or family involvement in incident investigations is typically organized as a one-time interview event. Interviews with patients or their families were considered to be valuable and important in their own right and seen as a way to do justice to the individual needs of the patient or their family. Yet, the usefulness and validity of the patient or family perspective for incident investigations was often seen to be limited, with the professional perspective afforded more weight. This was particularly the case when the patient or their family were unable to provide verifiable details of the incident under investigation. Study participants described challenges when involving patients or family members, including in relation to the available timeframe for incident investigations, legal issues, managing trust and working with intense emotions. Conclusions: We propose that by placing patient and family criteria of significance at the centre of incident investigations (i.e. an ‘emic’ research approach), hospitals may be able to expand their learning potential and improve patient-centeredness following an incident
Good practices for agrobiodiversity management
Native agricultural genetic resources have been generally under-valued, therefore, some initiatives have been taken through Global In-situ agrobiodiversity project joinly implemented by NARC, LI-BIRD and Bioversity International since 1997 in Nepal for conservation and sustainable use of agrobiodiversity on-farm. Global in-situ project (1997-2006) has developed
many good practices for agrobiodiversity management which are published in On-farm Management of Agricultural Biodiversity in Nepal: Good Practices 2006 (B Sthapit, P Shrestha and M Upadyay, eds). A good practice is a process or methodology or action that is effective and successful; environmentally, economically and socially sustainable; technically feasible; inherently participatory; replicable and adaptable, that has been proven to work well and produce good results. It is a successful experience tested and validated in achieving its objective. For further widening the scope of good practices in the country, NAGRC, LI-BIRD
and Bioversity International have generated, tested and adapted a number of good practices in four sites, Jungu, Dolakha; Ghapanpokhara, Lamjung; Hanku, Jumla; and Chippra, Humla through a project Integrating Traditional Crop Genetic Diversity into Technology: Using a Biodiversity Portfolio Approach to Buffer against Unpredictable Environmental Change in the
Nepal Himalayas , commonly called as Local Crop Project (LCP) from 2014 to 2019. Good practices listed here are well tested and adapted by the communtiies in the fields, shown their positive impact, shared and discussed among the relevant stakholders. Project team have tested and validated many good practices, however, we have included 22 good practices that are worth sharing for its dessimination and mainstreaming. These practices, though specially based on eight crops (rice, bean, barley, foxtail millet, proso millet, amaranth and buckwheat), can be widely applicable to other agricultural genetic ressources in different locations, national and globally
Low temperature microwave emission from molecular clusters
We investigate the experimental detection of the electromagnetic radiation
generated in the fast magnetization reversal in Mn12-acetate at low
temperatures. In our experiments we used large single crystals and assemblies
of several small single crystals of Mn12-acetate placed inside a cylindrical
stainless steel waveguide in which an InSb hot electron device was also placed
to detect the radiation. All this was set inside a SQUID magnetometer that
allowed to change the magnetic field and measure the magnetic moment and the
temperature of the sample as the InSb detected simultaneously the radiation
emitted from the molecular magnets. Our data show a sequential process in which
the fast inversion of the magnetic moment first occurs, then the radiation is
detected by the InSb device, and finally the temperature of the sample
increases during 15 ms to subsequently recover its original value in several
hundreds of milliseconds.Comment: changed conten
Effect of chronic kidney disease on serum resistin level
Background: Chronic Kidney Diseases (CKD) of all etiologies are usually associated with Insulin Resistance (IR). Resistin is also a protein associated with IR. Some studies conducted abroad have shown that resistin level is higher among CKD patients.Objective: To test if serum resistin level is significantly higher in CKD patients compared to normal individuals.Patients and Methods: 96 CKD patients and 97 normal individuals were included in the study. Written informed consent was obtained from every individual.Results: Serum resistin level was higher in CKD patients compared to control subjects. The difference in serum resistin level between two groups was statistically significant.Conclusion: Our study is probably the first study in India comparing serum resistin levels of CKD patients vis-à-vis control subjects. Further cellular research may be needed to explore this relation.Key words: Chronic kidney disease, HOMA-IR, insulin resistance, resisti
- …