Faktor-Faktor Yang Berhubungan Dengan Pemanfaatan Penolong Persalinan Di Desa Moyongkota Baru Kecamatan Modayag Barat

Latar belakang : Persalinan merupakan hal yang sangat kompleks karena disatusisi terjadi kebahagiaan menjelang kelahiran anak tetapi di sisilain terjadi resiko-resiko yang mungkin mengancam keselamatan ibu dan bayi. Di desa Moyongkota Baru Kecamatan Modayag Barat sebagian besar ibu bersalin memanfaatkan dukun sebagai penolong persalinannya dibandingkan dengan pemanfaatan penolong persalinan oleh tenaga kesehatan.Tujuan : Penelitian ini bertujuan untuk mengetahui faktor - faktor yang berhubungan dengan pemanfaatan penolong persalinan pada ibu bersalin di desa Moyongkota Baru Kecamatan Modayag Barat.Metode : Penelitian ini menggunakan desain penelitian observasional analitik dengan rancangan penelitian cross sectional study. Populasi dalam penelitian ini yaitu seluruh ibu yang bersalin pada bulan September – Oktober 2013 di Desa Moyongkota Baru Kecamatan Modayag Barat. Sampel yang digunakan adalah Quota sampling yaitu sampel dikumpulkan sampai mencapai jumlah yang diinginkan, jumlah sampel yang diinginkan adalah 50 responden.Hasil Penelitian : Berdasarkan hasil uji chi square diketahui bahwa faktor pengetahuan (ρ=0,006) dan dukungan suami (ρ=0,001) berhubungan signifikan terhadap pemanfaatan penolong persalinan, sedang kanfaktor status ekonomi tidak berhubungan signifikan dengan pemanfaatan penolong persalinan dengan nilai ρ=0,206.Kesimpulan : 58% ibu bersalin di desa Moyongkota Baru Kecamatan Modayag Barat Kabupaten Bolaang Mongondow Timur memanfaatkan penolong persalinan oleh dukun/paraji dibandingkan ibu bersalin yang memanfaatkan penolong persalinan oleh bidan (14%) dan penolong persalinan olehdokter (28%)

Solvent-Mediated Crystallization of Nanocrystal 3D Assemblies of Silver Nanocrystals: Unexpected Superlattice Ripening

Solvent–ligand interactions in colloidal nanocrystals are of significant importance as they can be used to modulate the way they pack into superlattices. Here, we demonstrate that the crystal structures of the nanocrystal superlattices made of 2.2 nm Ag nanocrystals can be controlled by using different carrier solvents. Specifically, the superlattice structures are tuned from body-centered cubic (<i>bcc</i>) to face-centered cubic (<i>fcc</i>) when varying solvents from hexane to tetrachloroethylene (TCE). Furthermore, by simultaneously annealing these two samples at different temperatures, <i>bcc</i> structures originating from hexane solutions are dominated by a simple coalescence mechanism, while the <i>fcc</i> structure stemming from TCE solutions undergoes an Ostwald ripening process that can produce a variety of binary nanocrystal superlattices such as NaCl, AlB₂, NaZn₁₃, and MgZn₂, the formation of those structures being well explained by a pure entropy driven process. This is believed to be due to variations in the ligand coverage ratio of the nanocrystals in different solvents that are changing the superlattice structures’ stability. Those findings provide insights into the solvent-mediated nanocrystal superlattices and the Ostwald ripening process in nanocrystal superlattices

Metal–Metal Binary Nanoparticle Superlattices: A Case Study of Mixing Co and Ag Nanoparticles

Here, Co/Ag binary nanoparticle superlattices were engineered. It is demonstrated that the Ag/Co nanoparticle size ratio is the dominating factor in the formation of binary nanoparticle superlattices. However, regardless of the relative ratio concentration of Co and Ag nanoparticles, the deposition temperature, <i>T</i>_d markedly changes the crystalline structure of binary superlattices. A systematic study of these parameters is presented in order to shed light on the driving force in the formation of binary metallic nanoparticle superlattices. For metal Co and Ag nanoparticles, the interparticle potential pairs are considered to be strong, but entropy is still the main driving force for the assembling into binary nanoparticle superlattices, rather than the energy arising from the interparticle interactions

Computational Matching of Surface Plasmon Resonance: Interactions between Silver Nanoparticles and Ligands

A multilayer model of a single coated nanoparticle has been refined through finite elements method based simulations and resulted in a successful matching of the experimental UV–visible spectra of ligand-coated silver nanoparticles. The computational matching of the surface plasmon resonance (SPR) band reveals both a ligand-type dependence of the effective plasma frequency and a size dependence of the SPR damping effect within the modeled nanoparticle. The observed differences of effective plasma frequency between thiol and amine-coated nanoparticles are consistent with the already known stronger bonding of thiols on silver compared to amines. The significant increase of the damping effect at the surface of the nanoparticle when increasing their size suggests an inverse relation between the ligand packing density and the nanoparticle size, which is supported by the expected influence of the surface curvature radius on the ligand packing

Ligand Exchange Governs the Crystal Structures in Binary Nanocrystal Superlattices

The surface chemistry in colloidal nanocrystals on the final crystalline structure of binary superlattices produced by self-assembly of two sets of nanocrystals is hereby demonstrated. By mixing nanocrystals having two different sizes and the same coating agent, oleylamine (OAM), the binary nanocrystal superlattices that are produced, such as NaCl, AlB₂, NaZn₁₃, and MgZn₂, are well in agreement with the crystalline structures predicted by the hard-sphere model, their formation being purely driven by entropic forces. By opposition, when large and small nanocrystals are coated with two different ligands [OAM and dodecanethiol (DDT), respectively] while keeping all other experimental conditions unchanged, the final binary structures markedly change and various structures with lower packing densities, such as Cu₃Au, CaB₆, and quasicrystals, are observed. This effect of the nanocrystals’ coating agents could also be extended to other binary systems, such as Ag–Au and CoFe₂O₄–Ag supracrystalline binary lattices. In order to understand this effect, a mechanism based on ligand exchange process is proposed. Ligand exchange mechanism is believed to affect the thermodynamics in the formation of binary systems composed of two sets of nanocrystals with different sizes and bearing two different coating agents. Hence, the formation of binary superlattices with lower packing densities may be favored kinetically because the required energetic penalty is smaller than that of a denser structure

Beyond Entropy: Magnetic Forces Induce Formation of Quasicrystalline Structure in Binary Nanocrystal Superlattices

Here, it is shown that binary superlattices of Co/Ag nanocrystals with the same size, surface coating, differing by their type of crystallinity are governed by Co–Co magnetic interactions. By using 9 nm amorphous-phase Co nanocrystals and 4 nm polycrystalline Ag nanocrystals at 25 °C, triangle-shaped NaCl-type binary nanocrystal superlattices are produced driven by the entropic force, maximizing the packing density. By contrast, using ferromagnetic 9 nm single domain (<i>hcp</i>) Co nanocrystals instead of amorphous-phase Co, dodecagonal quasicrystalline order is obtained, together with less-packed phases such as the CoAg₁₃ (NaZn₁₃-type), CoAg (AuCu-type), and CoAg₃ (AuCu₃-type) structures. On increasing temperature to 65 °C, 9 nm <i>hcp</i> Co nanocrystals become superparamagnetic, and the system yields the CoAg₃ (AuCu₃-type) and CoAg₂ (AlB₂-type) structures, as observed with 9 nm amorphous Co nanocrystals. Furthermore, by decreasing the Co nanocrystal size from 9 to 7 nm, stable AlB₂-type binary nanocrystal superlattices are produced, which remain independent of the crystallinity of Co nanocrystals with the superparamagnetic state

Surface Plasmon Resonance Properties of Silver Nanocrystals Differing in Size and Coating Agent Ordered in 3D Supracrystals

Silver nanocrystals differing in coating agent and size self-assembled into thin supracrystalline films. The surface plasmon resonance (SPR) properties of these assemblies are presented herein. Nanocrystal size, interparticle distance, and coating agent play key roles in the plasmonic coupling of Ag nanocrystals within supracrystals. Here, we demonstrate experimentally that the predictions for 2D self-assemblies remains valid for thin 3D superlattices. The absorption spectra in the visible range were found to be markedly dependent on the incidence of the light source and confirmed the appearance of a splitting of the dipolar surface band into two components at increasing incidence angle. The major parameter inducing the splitting of the SPR band was found to be the relative ratio between the average distance of the nanocrystals and their diameters. The nature of the coating agent was also found to be of particular importance: Theoretical predictions and experimental data were in agreement for alkylamine-coated nanocrystals but differed for thiol-coated nanocrystals

Effect of Divalent Counterions on Polyelectrolyte Multilayer Properties

When exposed to divalent counterion solutions, polyelectrolyte multilayer (PEM) films of poly­(diallyl­dimethyl­ammonium chloride) and sodium poly­(styrene­sulfonate) (NaPSS) prepared in the presence of monovalent salt, or equilibrated with such a salt, are physically cross-linked by divalent counterion incorporation, altering PEM properties significantly. The rapid cross-linking was monitored by the quartz crystal microbalance with dissipation (QCM-D) method, which finds PEM deswelling and rigidification after exposures to a low concentration of Cu­(NO₃)₂; at higher concentration, deswelling is countered by increased PEM uptake of the salt, which disrupts polyelectrolyte–polyelectrolyte ion pairs. Divalent ion incorporation into PEMs has the character of ion exchange, and incorporated divalent ions are quickly and completely removed when presented with monovalent salt solution but not with water. While counterion cross-linking extends across the bulk of the PEM, the fraction of exchanged counterions remains low. Entropically driven binding of divalent ions to NaPSS in solution was studied for Cu­(NO₃)₂ and other divalent nitrate salts by isothermal titration microcalorimetry and dynamic light scattering to support the QCM-D conclusions

The difference of codon usage.

<p>The difference of codon usage.</p

Map of the ECS showing the locations of the sampling stations.

<p>Map of the ECS showing the locations of the sampling stations.</p