3,063 research outputs found
Hara-kiri through anal orifice: a first-of-its-kind case.
Constipation and obstruction are distressing problems which not promptly treated can lead to dangerous complications. A common and potentially dangerous gastrointestinal problem is faecal impaction. Early diagnosis and prompt treatment avoids complications. Apart from manual extraction proximal and distal washout are the available options. However, the key lies in identifying the etiology of the problems and nipping it in the bud. We here present a first-of-its-kind case in which a female pulled out about 2 feet of her large intestine from her anal orifice after experiencing constipation for a period of two days. Damage control surgery was done and the patient was left with a permanent illeostomy
A Practical Synthesis of Bridged Diarylacetylenes
An efficient and practical synthesis of bridged diarylacetylenes in multigram quantities has been successfully carried out using high-yielding (classical) synthetic methods and readily available starting materials. The structural analysis of the representative bridged diarylacetylenes by X-ray crystallography strongly suggests that conformations, bending of the linear triple bond, and the angle between the mean planes of aromatic rings in various bridged diarylacetylenes are governed by the pâĎ conjugation among the aromatic rings and the ethereal groups. Furthermore, the synthetic scheme also allows the preparation of (appropriately) bromo-substituted bridged diarylacetylenes which hold potential for their future usage for the preparation of polymeric analogues as well as the hexaarylbenzene derivatives for potential applications in the emerging area of molecular electronics and nanotechnology
Inequalities and bounds for quasi-symmetric 3-designs
AbstractQuasi-symmetric 3-designs with block intersection numbers x and y(0⊽x<y<k) are studied, several inequalities satisfied by the parameters of a quasi-symmetric 3-designs are obtained. Let D be a quasi-symmetric 3-design with the block size k and intersection numbers x, y; y>x⊞1 and suppose DⲠdenote the complement of D with the block size kⲠand intersection numbers xⲠand yâ˛. If k â1 ⊽x + y then it is proved that xⲠ+ yⲠ⊽ kâ˛. Using this it is shown that the quasi-symmetric 3-designs corresponding to y = x + 1, x + 2 are either extensions of symmetric designs or designs corresponding to the Witt-design (or trivial design, i.e., v = k + 2) or the complement of above designs
FHBC, a Hexaâ\u3cem\u3eperi\u3c/em\u3eâhexabenzocoroneneâFluorene Hybrid: A Platform for Highly Soluble, Easily Functionalizable HBCs with an Expanded Graphitic Core
Materials based upon hexaâperiâhexabenzocoronenes (HBCs) show significant promise in a variety of photovoltaic applications. There remains the need, however, for a soluble, versatile, HBCâbased platform, which can be tailored by incorporation of electroactive groups or groups that can prompt selfâassembly. The synthesis of a HBCâfluorene hybrid is presented that contains an expanded graphitic core that is highly soluble, resists aggregation, and can be readily functionalized at its vertices. This new HBC platform can be tailored to incorporate six electroactive groups at its vertices, as exemplified by a facile synthesis of a representative hexaaryl derivative of FHBC. Synthesis of new FHBC derivatives, containing electroactive functional groups that can allow controlled selfâassembly, may serve as potential longârange chargeâtransfer materials for photovoltaic applications
On the role of entanglement and correlations in mixed-state quantum computation
In a quantum computation with pure states, the generation of large amounts of
entanglement is known to be necessary for a speedup with respect to classical
computations. However, examples of quantum computations with mixed states are
known, such as the deterministic computation with one quantum qubit (DQC1)
model [Knill and Laflamme, Phys. Rev. Lett. 81, 5672 (1998)], in which
entanglement is at most marginally present, and yet a computational speedup is
believed to occur. Correlations, and not entanglement, have been identified as
a necessary ingredient for mixed-state quantum computation speedups. Here we
show that correlations, as measured through the operator Schmidt rank, are
indeed present in large amounts in the DQC1 circuit. This provides evidence for
the preclusion of efficient classical simulation of DQC1 by means of a whole
class of classical simulation algorithms, thereby reinforcing the conjecture
that DQC1 leads to a genuine quantum computational speedup
A Search for Blues Brothers: X-ray Crystallographic/Spectroscopic Characterization of the Tetraarylbenzidine Cation Radical as a Product of Aging of Solid Magic Blue
Magic blue (MB+Ë SbCl6â salt), i.e. tris-4-bromophenylamminium cation radical, is a routinely employed one-electron oxidant that slowly decomposes in the solid state upon storage to form so called âblues brothersâ, which often complicate the quantitative analyses of the oxidation processes. Herein, we disclose the identity of the main âblues brotherâ as the cation radical and dication of tetrakis-(4-bromophenyl)benzidine (TAB) by a combined DFT and experimental approach, including isolation of TAB+Ë SbCl6â and its X-ray crystallography characterization. The formation of TAB in aged magic blue samples occurs by a Scholl-type coupling of a pair of MB followed by a loss of molecular bromine. The recognition of this fact led us to the rational design and synthesis of tris(2-bromo-4-tert-butylphenyl)amine, referred to as âblues cousinâ (BC: Eox1 = 0.78 V vs. Fc/Fc+, Îťmax(BC+Ë) = 805 nm, Îľmax = 9930 cmâ1 Mâ1), whose oxidative dimerization is significantly hampered by positioning the sterically demanding tert-butyl groups at the para-positions of the aryl rings. A ready two-step synthesis of BC from triphenylamine and the high stability of its cation radical (BC+Ë) promise that BC will serve as a ready replacement for MB and an oxidant of choice for mechanistic investigations of one-electron transfer processes in organic, inorganic, and organometallic transformations
A controlled clinical trial to evaluate the efficacy of Shalaparnyadi Kwatha in the management of Vataja Grahani
Background: Current mechanized life, irregular dietary patterns, irregularity in daily practices, junk food indulgence, stressful life, over usage of pesticides and chemicals leads to various gastro intestinal disorders. These factors hamper the digestive capacity of individuals and develop the disease Grahani. Shalaparnyadi Kwatha mentioned in treatment of Vataja Grahani in Sharangadhara Samhita is taken up for study in the management of Vataja Grahani. Objective: To evaluate the efficacy of Shalapanryadi Kwatha in Vataja Grahani. Method: The study was a double arm open labelled controlled clinical trial with pre and post-test study design. There were total of 41 subjects involved in the study and were divided into two groups - Group A (trial group) with 21 subjects and Group B (controlled group) with 20 subjects. Group A was administered with Shalaparnyadhi Kwatha and Panchamooladya Choorna and Group B was administered with Panchamooladya Choorna for 30 consecutive days. Result: A controlled clinical study was conducted on subjects of Vataja Grahani with Shalaparnyadi Kwatha and Panchamooladya Choorna in trial group and Panchamooladya Choorna in control group both the interventions were effective in management of Vataja Grahani. Based on the mean value and statistically significant difference between the groups, trial group showed better result than control group in Amayukta Mala Pravrutti and Udara Shoola. Conclusion: It can be concluded from the results that added effect of Shalaparnyadi Kwatha with Panchamooladya Choorna is more effective than Panchamooladya Choorna alone
Static dielectric response of icosahedral fullerenes from C60 to C2160 by an all electron density functional theory
The static dielectric response of C60, C180, C240, C540, C720, C960, C1500,
and C2160 fullerenes is characterized by an all-electron density-functional
method. First, the screened polarizabilities of C60, C180, C240, and C540, are
determined by the finite-field method using Gaussian basis set containing 35
basis functions per atom. In the second set of calculations, the unscreened
polarizabilities are calculated for fullerenes C60 through C2160 from the
self-consistent Kohn-Sham orbitals and eigen-values using the sum-over-states
method. The approximate screened polarizabilities, obtained by applying a
correction determined within linear response theory show excellent agreement
with the finite-field polarizabilities. The static dipole polarizability per
atom in C2160 is (4 Angstrom^3) three times larger than that in C60 (1.344
Angstrom^3). Our results reduce the uncertainty in various theoretical models
used previously to describe the dielectric response of fullerenes and show that
quantum size effects in polarizability are significantly smaller than
previously thought.Comment: RevTex, 3 figure
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