Methyl 2-amino-5-bromo­benzoate

In the title compound, C8H8BrNO2, the dihedral angle between the aromatic ring and the methyl acetate side chain is 5.73 (12)°. The mol­ecular conformation is stabilized by an intra­molecular N—H⋯O hydrogen bond, generating an S(6) ring. In the crystal, mol­ecules are connected by N—H⋯O inter­actions, generating zigzag chains running along the b-axis direction

Dianilinedibromidozinc(II)

In the title compound, [ZnBr2(C6H7N)2], the Zn atom (site symmetry 2) adopts a distorted tetra­hedral ZnN2Br2 geometry. In the crystal, mol­ecules are linked by N—H⋯Br hydrogen bonds, generating sheets containing R 2 2(8) loops

A Study of Medium Access Control Protocols for Wireless Body Area Networks

The seamless integration of low-power, miniaturised, invasive/non-invasive lightweight sensor nodes have contributed to the development of a proactive and unobtrusive Wireless Body Area Network (WBAN). A WBAN provides long-term health monitoring of a patient without any constraint on his/her normal dailylife activities. This monitoring requires low-power operation of invasive/non-invasive sensor nodes. In other words, a power-efficient Medium Access Control (MAC) protocol is required to satisfy the stringent WBAN requirements including low-power consumption. In this paper, we first outline the WBAN requirements that are important for the design of a low-power MAC protocol. Then we study low-power MAC protocols proposed/investigated for WBAN with emphasis on their strengths and weaknesses. We also review different power-efficient mechanisms for WBAN. In addition, useful suggestions are given to help the MAC designers to develop a low-power MAC protocol that will satisfy the stringent WBAN requirements.Comment: 13 pages, 8 figures, 7 table

1-(5-Hydr­oxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)ethanone: a new monoclinic polymorph

The title compound, C12H12N2O2, crystallized in the monolinic space group P21/n, with two independent mol­ecules (A and B) in the asymmetric unit. This is in contrast to the first monoclinic polymorph reported [Cingolani et al. (2002 ▶). Inorg. Chem. 41, 1151–116], which crystallized in the space group C2/c with one independent mol­ecule per asymmetric unit. The dihedral angles between the two rings differ slightly; in mol­ecule A it is 4.90 (11)° and in mol­ecule B it is 16.05 (13)°. In both mol­ecules, there is an intra­molecular O—H⋯O hydrogen bond involving the hydroxyl substituent and the carbonyl O atom of the adjacent acetyl group. In the crystal structure, mol­ecules A and B are linked via a C—H⋯N inter­action. There are also some weak C—H⋯π inter­actions involving the phenyl ring of mol­ecule A and H atoms of the acetyl groups of both mol­ecules

Metric dimensions of bicyclic graphs

The distance d(va, vb) between two vertices of a simple connected graph G is the length of the shortest path between va and vb. Vertices va, vb of G are considered to be resolved by a vertex v if d(va, v) 6= d(vb, v). An ordered set W = fv1, v2, v3, . . . , vsg V(G) is said to be a resolving set for G, if for any va, vb 2 V(G), 9 vi 2 W 3 d(va, vi) 6= d(vb, vi). The representation of vertex v with respect to W is denoted by r(vjW) and is an s-vector(s-tuple) (d(v, v1), d(v, v2), d(v, v3), . . . , d(v, vs)). Using representation r(vjW), we can say that W is a resolving set if, for any two vertices va, vb 2 V(G), we have r(vajW) 6= r(vbjW). A minimal resolving set is termed a metric basis for G. The cardinality of the metric basis set is called the metric dimension of G, represented by dim(G). In this article, we study the metric dimension of two types of bicyclic graphs. The obtained results prove that they have constant metric dimension

2-Ethyl-2,3-dihydro-1,2-benzothia­zole-1,1,3-trione

In the title mol­ecule, C9H9NO3S, the bond lengths and angles fall within normal ranges. All nine ring atoms almost lie in a common plane (r.m.s. deviation 0.021 Å). In the crystal, symmetry-related mol­ecules are linked via C—H⋯O hydrogen bonds, forming a three-dimensional network

N-(2-Meth­oxy­phen­yl)-4-methyl­benzene­sulfonamide

In the title compound, C14H15NO3S, the geometry around the S atom of the SO2 group is distorted tetra­hedral. The meth­oxy- and methyl-substituted aromatic rings are oriented at a dihedral angle of 71.39 (9)°. Inter­molecular N—H⋯O hydrogen bonds form inversion dimers, which stabilize the crystal structure

2-(Phenyl­sulfan­yl)pyridine-3-carboxylic acid

The title compound, C12H9NO2S, belongs to the nitro­gen-containing group of heterocyclic organic compounds and crystallized with two mol­ecules per asymmetric unit. In the crystal, both molecules form inversion dimers linked by pairs of O—H—O hydrogen bonds. Weak symmetry-related C—H—O inter­actions link the carboxyl dimers along b axis. The dihedral angle between the two aromatic rings in the two mol­ecules are 55.75 (14) and 58.33 (13)°

N-[2-(Amino­carbon­yl)phen­yl]-4-hydr­oxy-2-methyl-2H-1,2-benzothia­zine-3-carboxamide 1,1-dioxide

In the title compound, C17H15N3O5S, the thia­zine ring adopts a distorted half-chair conformation. The mol­ecular structure is stabilized by intra­molecular N—H⋯O, N—H⋯N and O—H⋯O hydrogen bonding. Pairs of mol­ecules are bound together as centrosymmetric dimers through N—H⋯O hydrogen bonds