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### Algorithmic Aspects of Semitotal Domination in Graphs [article]

Michael A. Henning, Arti Pandey
2017 arXiv   pre-print
For a graph G=(V,E), a set D ⊆ V is called a semitotal dominating set of G if D is a dominating set of G, and every vertex in D is within distance 2 of another vertex of D. The Minimum Semitotal Domination problem is to find a semitotal dominating set of minimum cardinality. Given a graph G and a positive integer k, the Semitotal Domination Decision problem is to decide whether G has a semitotal dominating set of cardinality at most k. The Semitotal Domination Decision problem is known to be
more » ... complete for general graphs. In this paper, we show that the Semitotal Domination Decision problem remains NP-complete for planar graphs, split graphs and chordal bipartite graphs. We give a polynomial time algorithm to solve the Minimum Semitotal Domination problem in interval graphs. We show that the Minimum Semitotal Domination problem in a graph with maximum degree Δ admits an approximation algorithm that achieves the approximation ratio of 2+3(Δ+1), showing that the problem is in the class log-APX. We also show that the Minimum Semitotal Domination problem cannot be approximated within (1 - ϵ) |V| for any ϵ > 0 unless NP ⊆ DTIME (|V|^O( |V|)). Finally, we prove that the Minimum Semitotal Domination problem is APX-complete for bipartite graphs with maximum degree 4.

### Some Algorithmic Results on Restrained Domination in Graphs [article]

Arti Pandey, B.S. Panda
2016 arXiv   pre-print
A set D⊆ V of a graph G=(V,E) is called a restrained dominating set of G if every vertex not in D is adjacent to a vertex in D and to a vertex in V ∖ D. The Minimum Restrained Domination problem is to find a restrained dominating set of minimum cardinality. Given a graph G, and a positive integer k, the Restrained Domination Decision problem is to decide whether G has a restrained dominating set of cardinality a most k. The Restrained Domination Decision problem is known to be NP-complete for
more » ... ordal graphs. In this paper, we strengthen this NP-completeness result by showing that the Restrained Domination Decision problem remains NP-complete for doubly chordal graphs, a subclass of chordal graphs. We also propose a polynomial time algorithm to solve the Minimum Restrained Domination problem in block graphs, a subclass of doubly chordal graphs. The Restrained Domination Decision problem is also known to be NP-complete for split graphs. We propose a polynomial time algorithm to compute a minimum restrained dominating set of threshold graphs, a subclass of split graphs. In addition, we also propose polynomial time algorithms to solve the Minimum Restrained Domination problem in cographs and chain graphs. Finally, we give a new improved upper bound on the restrained domination number, cardinality of a minimum restrained dominating set in terms of number of vertices and minimum degree of graph. We also give a randomized algorithm to find a restrained dominating set whose cardinality satisfy our upper bound with a positive probability.

### Genetics in medicine

Arti S Pandey
2017 Journal of Kathmandu Medical College
Genetics in medicine Pandey AS Arti S Pandey, Professor, Department of Biochemistry, Kathmandu Medical College (Basic Sciences) in cell multiplication and repair triggers cancer.  ...

### Complexity and Algorithms for Semipaired Domination in Graphs [article]

Michael A. Henning, Arti Pandey, Vikash Tripathi
2019 arXiv   pre-print
The class of GP4 graphs was introduced by Henning and Pandey in [15] . Below we recall the definition of GP4 graphs.  ...

### A linear-time algorithm for semitotal domination in strongly chordal graphs [article]

Vikash Tripathi, Arti Pandey, Anil Maheshwari
2021 arXiv   pre-print
Henning and Pandey in [20] also asked to resolve the complexity status of the problem in strongly chordal graphs.  ...  Henning and Pandey studied the approximation hardness of MINIMUM SEMITOTAL DOMINATION problem [20] .  ...  Henning and Pandey in [20] , also asked to find the complexity status of the problem in strongly chordal graphs.  ...

### Algorithmic aspects of disjunctive domination in graphs [article]

B.S. Panda, Arti Pandey, S. Paul
2015 arXiv   pre-print
For a graph G=(V,E), a set D⊆ V is called a disjunctive dominating set of G if for every vertex v∈ V∖ D, v is either adjacent to a vertex of D or has at least two vertices in D at distance 2 from it. The cardinality of a minimum disjunctive dominating set of G is called the disjunctive domination number of graph G, and is denoted by γ_2^d(G). The Minimum Disjunctive Domination Problem (MDDP) is to find a disjunctive dominating set of cardinality γ_2^d(G). Given a positive integer k and a graph
more » ... , the Disjunctive Domination Decision Problem (DDDP) is to decide whether G has a disjunctive dominating set of cardinality at most k. In this article, we first propose a linear time algorithm for MDDP in proper interval graphs. Next we tighten the NP-completeness of DDDP by showing that it remains NP-complete even in chordal graphs. We also propose a ((Δ^2+Δ+2)+1)-approximation algorithm for MDDP in general graphs and prove that MDDP can not be approximated within (1-ϵ) (|V|) for any ϵ>0 unless NP ⊆ DTIME(|V|^O( |V|)). Finally, we show that MDDP is APX-complete for bipartite graphs with maximum degree 3.

### Complexity of Paired Domination in AT-free and Planar Graphs [article]

Vikash Tripathi, Ton Kloks, Arti Pandey, Kaustav Paul, Hung-Lung Wang
2021 arXiv   pre-print
For a graph G=(V,E), a subset D of vertex set V, is a dominating set of G if every vertex not in D is adjacent to atleast one vertex of D. A dominating set D of a graph G with no isolated vertices is called a paired dominating set (PD-set), if G[D], the subgraph induced by D in G has a perfect matching. The Min-PD problem requires to compute a PD-set of minimum cardinality. The decision version of the Min-PD problem remains NP-complete even when G belongs to restricted graph classes such as
more » ... rtite graphs, chordal graphs etc. On the positive side, the problem is efficiently solvable for many graph classes including intervals graphs, strongly chordal graphs, permutation graphs etc. In this paper, we study the complexity of the problem in AT-free graphs and planar graph. The class of AT-free graphs contains cocomparability graphs, permutation graphs, trapezoid graphs, and interval graphs as subclasses. We propose a polynomial-time algorithm to compute a minimum PD-set in AT-free graphs. In addition, we also present a linear-time 2-approximation algorithm for the problem in AT-free graphs. Further, we prove that the decision version of the problem is NP-complete for planar graphs, which answers an open question asked by Lin et al. (in Theor. Comput. Sci., 591 (2015): 99-105 and Algorithmica, 82 (2020) :2809-2840).

### TESS observations of TX Col: Rapidly varying accretion flow [article]

Nikita Rawat, J. C. Pandey, Arti Joshi
2021 arXiv   pre-print
Recently, Pandey et al. (2021, in preparation) also found its variable diskoverflow accretion nature using Chandra, Swift, and Suzaku observations.  ...

### Phytochemical composition, in vitro antioxidant activity and antibacterial mechanisms of Neolamarckia cadamba fruits extracts

2017 Figshare
Aqueous extracts of Neolamarckia cadamba fruits prepared at different maturity stages were used for the analysis of various phytochemicals, and their antioxidant and antibacterial activities were determined. Ripe fruit extract had highest phenolics (3.14 mM GAE/ g fruit extract) with caffeic acid, tannic acid, syringic acid and quercetin as major phenolic compounds. The ripe fruit extract showed lowest IC50 values in DPPH radical scavenging assay (231.33 μg fruit extract/ mL), and highest ABTS
more » ... adical scavenging activity (111.18 μM TEAC/g). Immature fruit extract showed lowest minimum inhibitory concentration against tested bacteria, and the antibacterial activity was probably due to membrane permeation, as was evident by leakage of genetic material and reduction in propidium iodide uptake by bacterium; and by inhibition of sugar and amino acid uptake. The appreciable amount of phenolic compounds and biological activities in the aqueous extracts of N. cadamba fruits suggests it's potential application as natural preservative.

### Field emission from crystalline niobium

Arti Dangwal Pandey, Günter Müller, Detlef Reschke, Xenia Singer
2009 Physical Review Special Topics. Accelerators and Beams
Pandey for support on the reinstallation of the oven in FESM, and A. Matheisen for electropolished niobium samples.  ...

### A 4-Pyridyltetrazole-based Zinc Metal-organic framework for photocatalytic degradation of methylene blue

Arti Chouhan, Ashutosh Pandey, Sadhana Singh, Subia Ambreen
2020 Zenodo
Acknowledgements Arti Chouhan gratefully acknowledged the DST, Government of India for taking financial assistance under the Women's Scientific Scheme (WOS-A).  ...

### Coffin-Siris Syndrome in Two Sisters in Nepal

Anil Ojha, Chin-To Fong, Arti Sharma Pandey
2013 Journal of Nepal Paediatric Society
Coffin-Siris syndrome (CSS) has the characteristic feature of brachydactyly of the fifth digit of hands and feet accompanying cognitive and developmental delay. There is an overlap of symptoms with other conditions making the diagnosis of CSS difficult. An algorithm to look for a set of characters was followed for diagnosis of CSS in two sisters in Nepal. This is the first case of CSS reported from this country.

### A 4-Pyridyltetrazole-based Zinc Metal-organic framework for photocatalytic degradation of methylene blue

Arti Chouhan, Ashutosh Pandey, Sadhana Singh, Subia Ambreen
2020 Zenodo
Acknowledgements Arti Chouhan gratefully acknowledged the DST, Government of India for taking financial assistance under the Women's Scientific Scheme (WOS-A).  ...

### Algorithm and Hardness Results for Outer-connected Dominating Set in Graphs [chapter]

B. S. Panda, Arti Pandey
2014 Lecture Notes in Computer Science
A set D ⊆ V of a graph G = (V, E) is called an outer-connected dominating set of G if for all v ∈ V , |NG[v] ∩ D| ≥ 1, and the induced subgraph of G on V \ D is connected. The Minimum Outer-connected Domination problem is to find an outer-connected dominating set of minimum cardinality of the input graph G. Given a positive integer k and a graph G = (V, E), the Outer-connected Domination Decision problem is to decide whether G has an outer-connected dominating set of cardinality at most k. The
more » ... uter-connected Domination Decision problem is known to be NP-complete for bipartite graphs. In this paper, we strengthen this NP-completeness result by showing that the Outerconnected Domination Decision problem remains NP-complete for perfect elimination bipartite graphs. On the positive side, we propose a linear-time algorithm for computing a minimum outer-connected dominating set of a chain graph, a subclass of bipartite graphs. We show that the Outer-connected Domination Decision problem can be solved in linear-time for graphs of bounded tree-width. We propose a ∆(G)approximation algorithm for the Minimum Outer-connected Domination problem, where ∆(G) is the maximum degree of G. On the negative side, we prove that the Minimum Outer-connected Domination problem cannot be approximated within a factor of (1 − ε) ln |V | for any ε > 0, unless NP ⊆ DTIME(|V | O(log log |V |) ). We also show that the Minimum Outer-connected Domination problem is APX-complete for graphs with bounded degree 4 and for bipartite graphs with bounded degree 7.

### Screening Mentally Retarded Children for Inborn Errors of Metabolism

Naveen K. Shreevastava, Arti S. Pandey
2017 Journal of Nepal Health Research Council
<p><strong>Background: </strong>Most inborn errors of metabolism result in mental retardation and death due to accumulation of abnormal metabolites in the tissues. The presence of abnormal metabolites in the urine of mentally retarded individuals has been used worldwide for detection of inborn errors of metabolism. The purpose of the study is to determine the prevalence of inborn error of metabolism in mentally retarded children.</p><p><strong>Methods: </strong>Random urine samples were
more » ... d from mentally retarded children at two institutes in Kathmandu, and also from 60 normal children from Duwakot, Nepal after obtaining consent from their parents. Urine was then tested for the presence of amino acids, keto-acids, mucopolysaccharides, fructose, glucose and protein using simple qualitative color reactions in the laboratory.</p><p><strong>Results: </strong>The tests detected eight cases of Phenylketonuria, which turned out to be false positive on paper chromatography. Three cases of presence of ketone bodies (acetoacetate), ten cases of α-ketoaciduria, two cases of mucopolysaccharidosis and twelve cases of fructosuria amongst the sixty-two urine samples were also found.</p><p><strong>Conclusions: </strong>Certain aminoacidurias, ketoacidurias and mucopolysaccharidoses might be present in the Nepalese population. Within consideration of errors, the samples tested positive should be evaluated by a higher end method to confirm the utility of these simple and cheap chemical tests. </p>
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