756 research outputs found
Richard Ernst (1933–2021)
Richard Ernst, pioneer of NMR spectroscopy and Nobel prize winner for chemistry, passed away on June 4th 2021 in his home town of Winterthur. He was among the developers of Fourier transform NMR spectroscopy, and later extended this to two- and higher-dimensional NMR spectroscopy. His work laid the foundations for present-day use of NMR spectroscopy as a universal tool to investigate materials and chemically or biologically relevant molecules
Borderline Aggregation Kinetics in ``Dry'' and ``Wet'' Environments
We investigate the kinetics of constant-kernel aggregation which is augmented
by either: (a) evaporation of monomers from finite-mass clusters, or (b)
continuous cluster growth -- \ie, condensation. The rate equations for these
two processes are analyzed using both exact and asymptotic methods. In
aggregation-evaporation, if the evaporation is mass conserving, \ie, the
monomers which evaporate remain in the system and continue to be reactive, the
competition between evaporation and aggregation leads to several asymptotic
outcomes. For weak evaporation, the kinetics is similar to that of aggregation
with no evaporation, while equilibrium is quickly reached in the opposite case.
At a critical evaporation rate, the cluster mass distribution decays as
, where is the mass, while the typical cluster mass grows with
time as . In aggregation-condensation, we consider the process with a
growth rate for clusters of mass , , which is: (i) independent of ,
(ii) proportional to , and (iii) proportional to , with . In
the first case, the mass distribution attains a conventional scaling form, but
with the typical cluster mass growing as . When , the
typical mass grows exponentially in time, while the mass distribution again
scales. In the intermediate case of , scaling generally
applies, with the typical mass growing as . We also give an
exact solution for the linear growth model, , in one dimension.Comment: plain TeX, 17 pages, no figures, macro file prepende
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The Psychiatrization of Poverty: Rethinking the Mental Health-Poverty Nexus
The positive association between ‘mental illness’ and poverty is one of the most well established in psychiatric epidemiology. Yet, there is little conclusive evidence about the nature of this relationship. Generally, explanations revolve around the idea of a vicious cycle, where poverty may cause mental ill health, and mental ill health may lead to poverty. Problematically, much of the literature overlooks the historical, social, political, and cultural trajectories of constructions of both poverty and ‘mental illness’. Laudable attempts to explore the social determinants of mental health sometimes take recourse to using and reifying psychiatric diagnostic categories that individualize distress and work to psychiatrically reconfigure ‘symptoms’ of oppression, poverty, and inequality as ‘symptoms’ of ‘mental illness’. This raises the paradoxical issue that the very tools that are used to research the relationship between poverty and mental health may prevent recognition of the complexity of that relationship. Looking at the mental health–poverty nexus through a lens of psychiatrization (intersecting with medicalization, pathologization, and psychologization), this paper recognizes the need for radically different tools to trace the messiness of the multiple relationships between poverty and distress. It also implies radically different interventions into mental health and poverty that recognize the landscapes in which lived realities of poverty are embedded, the political economy of psychiatric diagnostic and prescribing practices, and ultimately to address the systemic causes of poverty and inequality
Solid-phase-assisted synthesis of targeting peptide-PEG-oligo(ethane amino)amides for receptor-mediated gene delivery.
In the forthcoming era of cancer gene therapy, efforts will be devoted to the development of new efficient and non-toxic gene delivery vectors. In this regard, the use of Fmoc/Boc-protected oligo(ethane amino)acids as building blocks for solid-phase-supported assembly represents a novel promising approach towards fully controlled syntheses of effective gene vectors. Here we report on the synthesis of defined polymers containing the following: (i) a plasmid DNA (pDNA) binding domain of eight succinoyl-tetraethylenpentamine (Stp) units and two terminal cysteine residues; (ii) a central polyethylene glycol (PEG) chain (with twenty-four oxyethylene units) for shielding; and (iii) specific peptides for targeting towards cancer cells. Peptides B6 and c(RGDfK), which bind transferrin receptor and αvβ3 integrin, respectively, were chosen because of the high expression of these receptors in many tumoral cells. This study shows the feasibility of designing these kinds of fully controlled vectors and their success for targeted pDNA-based gene transfer
Potential health risks of complementary alternative medicines in cancer patients
Many cancer patients use complementary alternative medicines (CAMs) but may not be aware of the potential risks. There are no studies quantifying such risks, but there is some evidence of patient risk from case reports in the literature. A cross-sectional survey of patients attending the outpatient department at a specialist cancer centre was carried out to establish a pattern of herbal remedy or supplement use and to identify potential adverse side effects or drug interactions with conventional medicines. If potential risks were identified, a health warning was issued by a pharmacist. A total of 318 patients participated in the study. Of these, 164 (51.6%) took CAMs, and 133 different combinations were recorded. Of these, 10.4% only took herbal remedies, 42.1% only supplements and 47.6% a combination of both. In all, 18 (11.0%) reported supplements in higher than recommended doses. Health warnings were issued to 20 (12.2%) patients. Most warnings concerned echinacea in patients with lymphoma. Further warnings were issued for cod liver/fish oil, evening primrose oil, gingko, garlic, ginseng, kava kava and beta-carotene. In conclusion, medical practitioners need to be able to identify the potential risks of CAMs. Equally, patients should be encouraged to disclose their use. Also, more research is needed to quantify the actual health risks
The Use of Herbal Medications and Dietary Supplements by People with Mental Illness
This study examined the relationship between herbal medication and dietary supplement (HMDS) use and mental health characteristics. Data are drawn from a national household survey of the United States’ civilian, non-institutionalized population (N = 9,585). Psychiatric medication and HMDS use, psychiatric diagnoses and treatment needs, utilization and satisfaction were assessed. Compared to non-users, HMDS users were more likely to perceive themselves as having mental health needs, to have received mental health and primary care treatment, and to be dissatisfied with their overall healthcare. Psychiatric medication use was not related to HMDS use, and in multivariate analyses, HMDS use was associated with perceived mental health needs. Differences in use of specific HMDS between those with and without a psychiatric disorder were also examined. The use of HMDS warrants particular attention in persons with perceived mental health problems as these individuals may be turning to HMDS use for treatment of their symptoms
Why We Should Not Be Indifferent to Specification Choices for Difference‐in‐Differences
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/112198/1/hesr12270.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/112198/2/hesr12270-sup-0001-AuthorMatrix.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/112198/3/hesr12270-sup-0002-Appendix.pd
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