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This study examines the impact of remittances on school enrollment and the level of education attained among children aged 4–15 years in Pakistan. It uses a nationally representative survey, the Pakistan Social and Living Standards Measurement Survey for 2010/11. The migrant network variable at the village level interacting with the number of adults at the household level is used as an instrument for remittances. The results of the IV probit model show that children from remittance-receiving households are more likely to enroll in school. The marginal impact of remittances on school enrollment is larger for girls and for rural households. Hence, remittances help reduce regional and gender disparities in child school enrollment in Pakistan. The IV censored ordered probit model is used to investigate the impact of remittances on children’s grade attainment. The estimated impact is negative and significant, except for urban children, lowering the probability that a child will move to a higher grade.

Worldwide carbonate rocks are occurring abundantly. These carbonate rocks are a major class of sedimentary rocks group. Carbonate are sedimentary rocks formed at (or near) the Earth surface by precipitation from solution at surface temperatures. The two broad categories are limestone, which is composed of calcite or aragonite (different crystal forms of CaCO3) and dolostone, which is composed of the mineral dolomite (Ca Mg (CO3)2). Dolomite is not a simple mineral; it can have a variety of origin, can form as a primary precipitate, a diagenetic replacement, or as a hydrothermal/metamorphic phase, all that it requires is permeability, a mechanism that facilitates fluid flow, and a sufficient supply of magnesium. Dolomite can also form in lakes, on or beneath the shallow seafloor, in zones of brine reflux, and in early to late burial settings. It may form from seawater, from continental waters, from the mixing of basinal brines, the mixing of hypersaline brine with seawater, or the mixing of seawater with meteoric water, or via the cooling of basinal brines. Potential fluid sources are seawater and subsurface fluid of marine and/or meteoric origin: and addition Mg could be released from high-Mg calcite and smectite clays. The only abundant source of Mg2+ ions for early diagenetic surface and near-surface dolomitization is seawater. Dolomitization also creates new crystals, with new rhomb growth following the dissolution of less stable precursors. Dolomitization model and formation depend on the source dolomitization site and lastly, there must exist a favorable condition for a chemical reaction. One particular type of dolomite which may be a cement or a replacement is baroque dolomite, also called 'saddle' or 'white sparry' dolomite and known to mineral collectors as pearl spar. It is characterized by a warped crystal lattice.

In this article, we present proof-of-concept of Mary asymmetrically clipped (AC)-frequency-shift keying (FSK) for energy-efficient/low data rate visible light communications (VLC). M -ary AC-FSK uses the odd frequency waveforms from 2M -ary FSK; which exhibit half-wave symmetry. Owing to this half-wave symmetry, the negative amplitude excursions are clipped without loss of information. Hereby, we investigate the performance of three different receivers for M -ary AC-FSK exhibiting different complexities. These receivers are: (i) an optimal time-domain maximum likelihood (ML) receiver; (ii) 1tap discrete cosine transform (DCT) receiver; and (iii) a 2-tap harmonic receiver which exploits the spectral properties of AC-FSK waveforms. We shall exemplify that the 2-tap harmonic receiver overcomes the energy efficiency versus complexity trade-off that exists for optimal ML and 1-tap DCT receivers. Simulation results shall confirm that the performance of 2-tap harmonic receiver reaches the performance of the previously proposed unipolar (U)-FSK with the optimal receiver, but with a drastically reduced receiver complexity.