868 research outputs found
Detecting subsystem symmetry protected topological order via entanglement entropy
Subsystem symmetry protected topological (SSPT) order is a type of quantum
order that is protected by symmetries acting on lower-dimensional subsystems of
the entire system. In this paper, we show how SSPT order can be characterized
and detected by a constant correction to the entanglement area law, similar to
the topological entanglement entropy. Focusing on the paradigmatic
two-dimensional cluster phase as an example, we use tensor network methods to
give an analytic argument that almost all states in the phase exhibit the same
correction to the area law, such that this correction may be used to reliably
detect the SSPT order of the cluster phase. Based on this idea, we formulate a
numerical method that uses tensor networks to extract this correction from
ground-state wave functions. We use this method to study the fate of the SSPT
order of the cluster state under various external fields and interactions, and
find that the correction persists unless a phase transition is crossed, or the
subsystem symmetry is explicitly broken. Surprisingly, these results uncover
that the SSPT order of the cluster state persists beyond the cluster phase,
thanks to a new type of subsystem time-reversal symmetry. Finally, we discuss
the correction to the area law found in three-dimensional cluster states on
different lattices, indicating rich behavior for general subsystem symmetriesComment: 17 pages. v2: Published version, minor changes throughou
The physician's unique role in preventing violence: a neglected opportunity?
BACKGROUND: Episodes of explosive rage and violence comprise a symptom complex which can have a devastating effect on a person's life. In the community this behavior is seen as workplace violence, domestic abuse and road rage, while in the clinical setting, this behavior is rarely mentioned by patients, despite evidence that it can signify an important biological disorder that may afflict more than three percent of the population. DISCUSSION: Patients are often reluctant to seek help for episodic attacks of rage, especially attacks which are accompanied by physical violence. Although, in the past, clinicians have had few treatment options to offer, recent neuroscience advances have created new possibilities to understand and help patients with this neglected problem. No formal medical guidelines for treating violence exist; however, many patients can be helped by diagnosis, referral and treatment. Treatment can include pharmaceuticals and nutrients, as well as referral for anger management or behavioral therapy. SUMMARY: The astute clinician has an opportunity to positively impact an important problem through the diagnosis and treatment of patients with symptoms of intermittent explosive disorder
Conflict and Livelihood Decisions in the Chittagong Hill Tracts of Bangladesh
__Abstract__
We analyse rural household livelihood and child school enrolment
decisions
in the post-conflict setting of the Chittagong Hill Tracts (CHT) region of
Bangladesh. What makes this paper innovative is the use of current subjective perceptions
regarding the possibility of violence in the future and past actual experiences
of violence in explaining household economic decision-making. Preferences
are endogenous in line with behavioural economics. Regression results show that
heightened subjective perceptions of future violence and past actual experiences
of conflict influence current consumption and child enrolment and could encourage
risky mixed crop cultivation. The trauma emanating from past experiences
combined with current high perceptions of risk of violence may induce bolder
and riskier behaviour in line with prospect theories of risk. Furthermore, a postconflic
Disentangling the Taxonomy of the Mahseers (Tor spp.) of Malaysia: An Integrated Approach Using Morphology, Genetics and Historical Records
The establishment of appropriate taxonomic designations is essential for the effective management of fishery resources. Despite over a century of explorations and research, the cyprinid genus Tor represents a group of large-bodied freshwater fishes whose taxonomy and systematics remains poorly known. While five species of Tor are currently listed as “endangered” on the IUCN Red List, a further five out of 18 species currently recognized are assessed as “data deficient,” with at least one undescribed species, believed to be on the brink of extinction (i.e., the Humpback Mahseer endemic to the Cauvery River in India). Tor mahseers represent a suitable model for the application of an integrated approach using morphology, genetics, and historical records to resolve species identities, where one or more of these fundamental approaches may have been deficient in the past. Focusing specifically on the taxonomy and nomenclature of the Tor species recorded from Peninsular Malaysia, one of the aims of this review is to define the identity of two nominal species, T. tambra and T. tambroides. Original descriptions of these two nominal species contain little or practically no characters to distinguish them, and partly explains why secondary literature fails to conclusively determine species boundaries. A phylogenetic analysis of mahseer specimens from this region, based on publicly available and newly sequenced mitochondrial COX1 genes, does not support species designation based on previously established morphological features. More importantly, multiple tree-based species delimitation approaches showed that previously sequenced T. tambroides from Peninsular Malaysia and the newly described Tor species from Vietnam could not be delimited from the topotypic Tor tambra. A wider investigation of mahseer taxonomy covering all of Southeast Asia, using such an integrated approach is recommended to resolve the ambiguous taxonomy and is of profound importance for the conservation and management of exploited and farmed populations of these highly valued and iconic fish
A Critical Analysis of Chromotherapy and Its Scientific Evolution
Chromotherapy is a method of treatment that uses the visible spectrum (colors) of electromagnetic radiation to cure diseases. It is a centuries-old concept used successfully over the years to cure various diseases. We have undertaken a critical analysis of chromotherapy and documented its scientific evolution to date. A few researchers have tried to discover the underlying scientific principles, but without quantitative study. Sufficient published material can be found about the subject that provides a complete system of treatment focused on the treatment methodologies and healing characteristics of colors. A number of studies have elaborated the relationship between the human body and colors. We also show the possibility of carrying out diverse research into chromotherapy that is pertinent to deciphering the quantum mechanical dipole moment of water molecules. The quantum mechanical dipole moment as a result of the absorption of different colors, we conjecture, produces charge quantization phenomena. This review illustrates that the development of science in the field of electromagnetic radiation/energy can be very helpful in discovering new dimensions of this old theory
String order parameters for symmetry fractionalization in an enriched toric code
We study a simple model of symmetry-enriched topological order obtained by
decorating a toric code model with lower-dimensional symmetry-protected
topological states. We show that the symmetry fractionalization in this model
can be characterized by string order parameters, and that these signatures are
robust under the effects of external fields and interactions, up to the phase
transition point. This extends the recent proposal of [New Journal of Physics
21, 113016 (2019)] beyond the setting of fixed-point tensor network states, and
solidifies string order parameters as a useful tool to characterize and detect
symmetry fractionalization. In addition to this, we observe how the
condensation of an anyon that fractionalizes a symmetry forces that symmetry to
spontaneously break, and we give a proof of this in the framework of projected
entangled pair states. This phenomenon leads to a notable change in the phase
diagram of the toric code in parallel magnetic fields.Comment: Changes in title, astract and introdution. 11+7 pages, 7+3 figures, 2
table
Recessive mutations in the INS gene result in neonatal diabetes through reduced insulin biosynthesis
Heterozygous coding mutations in the INS gene that encodes preproinsulin were recently shown to be an important cause of permanent neonatal diabetes. These dominantly acting mutations prevent normal folding of proinsulin, which leads to beta-cell death through endoplasmic reticulum stress and apoptosis. We now report 10 different recessive INS mutations in 15 probands with neonatal diabetes. Functional studies showed that recessive mutations resulted in diabetes because of decreased insulin biosynthesis through distinct mechanisms, including gene deletion, lack of the translation initiation signal, and altered mRNA stability because of the disruption of a polyadenylation signal. A subset of recessive mutations caused abnormal INS transcription, including the deletion of the C1 and E1 cis regulatory elements, or three different single base-pair substitutions in a CC dinucleotide sequence located between E1 and A1 elements. In keeping with an earlier and more severe beta-cell defect, patients with recessive INS mutations had a lower birth weight (-3.2 SD score vs. -2.0 SD score) and were diagnosed earlier (median 1 week vs. 10 weeks) compared to those with dominant INS mutations. Mutations in the insulin gene can therefore result in neonatal diabetes as a result of two contrasting pathogenic mechanisms. Moreover, the recessively inherited mutations provide a genetic demonstration of the essential role of multiple sequence elements that regulate the biosynthesis of insulin in man
Synthesis of (cinnamate-zinc layered hydroxide) intercalation compound for sunscreen application
Background:
Zinc layered hydroxide (ZLH) intercalated with cinnamate, an anionic form of cinnamic acid (CA), an efficient UVA and UVB absorber, have been synthesized by direct method using zinc oxide (ZnO) and cinnamic acid as the precursor.
Results:
The resulting obtained intercalation compound, ZCA, showed a basal spacing of 23.9 Å as a result of cinnamate intercalated in a bilayer arrangement between the interlayer spaces of ZLH with estimated percentage loading of cinnamate of about 40.4 % w/w. The UV–vis absorption spectrum of the intercalation compound showed excellent UVA and UVB absorption ability. Retention of cinnamate in ZLH interlayers was tested against media usually came across with sunscreen usage to show low release over an extended period of time. MTT assay of the intercalation compound on human dermal fibroblast (HDF) cells showed cytotoxicity of ZCA to be concentration dependent and is overall less toxic than its precursor, ZnO.
Conclusions:
(Cinnamate-zinc layered hydroxide) intercalation compound is suitable to be used as a safe and effective sunscreen with long UV protection effect
Factors influencing job preferences of health workers providing obstetric care : results from discrete choice experiments in Malawi, Mozambique and Tanzania
BACKGROUND: Task shifting from established health professionals to mid-level providers (MLPs) (professionals who undergo shorter training in specific procedures) is one key strategy for reducing maternal and neonatal deaths. This has resulted in a growth in cadre types providing obstetric care in low and middle-income countries. Little is known about the relative importance of the different factors in determining motivation and retention amongst these cadres. METHODS: This paper presents findings from large sample (1972 respondents) discrete choice experiments to examine the employment preferences of obstetric care workers across three east African countries. RESULTS: The strongest predictors of job choice were access to continuing professional development and the presence of functioning human resources management (transparent, accountable and consistent systems for staff support, supervision and appraisal). Consistent with similar works we find pay and allowances significantly positively related to utility, but financial rewards are not as fundamental a factor underlying employment preferences as many may have previously believed. Location (urban vs rural) had the smallest average effect on utility for job choice in all three countries. CONCLUSIONS: These findings are important in the context where efforts to address the human resources crisis have focused primarily on increasing salaries and incentives, as well as providing allowances to work in rural areas
Percutaneous transhepatic biliary stenting
Objective: Bilary stenting with endoprosthesis is a palliative procedure to relieve malignant biliary obstruction. Percutaneous transhepatic technique has been employed whenever endoscopic technique was not possible or had failed.SETTING: Angiography/intervention suite, department of radiology, Aga Khan University hospital, Karachi.Methods: We present retrospective analysis of 17 patients with malignant jaundice who were treated with percutaneous techniques after the endoscopic route had failed.Results: The success rate was 94% with placement of single plastic stent in 14 patients, double stents in 3 patients and self-expandable stent in one patient. The overall complication rate was 41% including sepsis, liver abscess, biloma formation, biliary leakage and stent occlusion. There was one procedure related death due to severe sepsis.CONCLUSION: Percutaneous transhepatic biliary stenting is an alternative procedure to relieve malignant biliary obstruction with high complication rate and should be reserved for selected patients in whom endoscopic route has failed
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