On the kk-free divisor problem

Let $\Delta^{(k)}(x)$ denote the error term of the $k$-free divisor problem for $k\geq 2$. In this paper we establish an asymptotic formula of the integral $\int_1^T|\Delta^{(k)}(x)|^2dx$ for each $k\geq 4.

INTERLINKAGE IN THE RICE MARKET OF GHANA: MONEY-LENDING MILLERS ENHANCE EFFICIENCY

Most of the large-scale millers in Ghana provide a loan to the farmers under the agreement that the farmers will bring their paddy to them. This paper examines the effect of this interlinkage on the efficiency of rice milling. A quadratic cost function was estimated, and capacity utilization was calculated in relation to money lending. The results show that if the millers provide a loan to the farmers, the operating rate will increase by 24%.Crop Production/Industries,

Impacts of Water Supply Changes on the Rice Market of Lao PDR: Stochastic Analysis of Supply and Demand Model

Laotian rice producers in upland areas experience highly fluctuating yields and production and producers in wet season rice areas in the southern region face high price risk. This paper examines the exposure to risk of producers in both regions facing changes in water supplies. A supply and demand model of rice in Laos, considering water supply changes, is developed and stochastic elements are added to the model to represent uncertainty in climatic variables. Furthermore, the risks associated with price and production fluctuation are evaluated by using the differences between market and certainty equivalent prices. The results show that the coefficient of variation of production is higher in upland rice than wet and dry season rice, i.e., 0.3226, and if the fluctuation of water supply increases 20%, the coefficient of variation of production will increase about 20% for all type of rice cultivation. In the case of expanding water supply fluctuations, potentially due to climatic change, the price risk of wet season rice will increase from 48.5 kip to 150.8 kip while that of upland and dry season rice will increase from 66.4 kip to 94.9 kip and 14.3 kip to 20.5 kip respectively. Examining provincial price risk of wet season rice, the differences between market and certainty equivalent prices are 56.3 kip and 33.9 kip in Champasack and Attapeu provinces. The regions or provinces which suffer highly fluctuating production and price risk may need to consider alternative water management and harvesting methods.water supply change, rice supply and demand model, stochastic model, Lao PDR, Q11, Q25, Crop Production/Industries, Resource /Energy Economics and Policy,

On the average orders of the error term in the Dirichlet divisor problem

AbstractLet Δ(x) be the error term in the Dirichlet divisor problem. The purpose of this paper is to study the difference between two kinds of mean value formulas of Δ(x), that is, the mean value formulas ∫1xΔ(u)kdu and ∑n⩽xΔ(n)k with a natural number k. In particular we study the case k=2 and 3 in detail

Rice Miller Cluster in Ghana and Its Effects on Efficiency and Quality Improvement

This paper investigates the roles of industrial cluster on the efficiency of rice milling and the improvement of milled rice quality. The data were obtained in Kumasi area, central Ghana because the enhancement of domestic rice production is a urgent policy issue in this country, but little attention has been paid to the roles of clusters in post-harvest processing and marketing. Among 63 rice millers interviewed in the Kumasi area, 24 millers form a few clusters in the city of Kumasi, while others are scattered over 25 satellite towns around Kumasi, which enables us to examine the effect of the cluster. Regression analyses reveal that rice millers in the Kumasi clusters tend to adopt more advanced technology, and that the innovation increases milling efficiency and improves 1 milling quality. Moreover, it is found from the estimation of price determination functions that in the Kumasi clusters milled rice price is affected by milling quality namely the content of whole grain, while in the rural areas there is no clear relationship between milling quality and the price. This indicates that the clusters, probably because of the concentrated transactions, will foster informal quality grading system, which is critical for the market development. Therefore, the clusters in post-harvest industry will benefit not only the industry itself but also traders and producers, and in consequence will stimulate agricultural production.rice, miller, industrial cluster, efficiency, product quality, sub-Saharan Africa, Crop Production/Industries,

Dicyema Pax6 and Zic: tool-kit genes in a highly simplified bilaterian

<p>Abstract</p> <p>Background</p> <p>Dicyemid mesozoans (Phylum Dicyemida) are simple (8–40-cell) cephalopod endoparasites. They have neither body cavities nor differentiated organs, such as nervous and gastrointestinal systems. Whether dicyemids are intermediate between Protozoa and Metazoa (as represented by their "Mesozoa" classification) or degenerate species of more complex metazoans is controversial. Recent molecular phylogenetic studies suggested that they are simplified bilaterians belonging to the Lophotrochozoa. We cloned two genes developmentally critical in bilaterian animals (Pax6 and Zic), together with housekeeping genes (actin, fructose-bisphosphate aldolase, and ATP synthase beta subunit) from a dicyemid to reveal whether their molecular phylogeny supported the "simplification" hypothesis, and to clarify evolutionary changes in dicyemid gene structure and expression profiles.</p> <p>Results</p> <p>Genomic/cDNA sequence analysis showed that 1) the Pax6 molecular phylogeny and Zic intron positions supported the idea of dicyemids as reduced bilaterians; 2) the aa sequences deduced from the five genes were highly divergent; and 3) <it>Dicyema </it>genes contained very short introns of uniform length. In situ hybridization analyses revealed that <it>Zic </it>genes were expressed in hermaphroditic gonads, and <it>Pax6 </it>was expressed weakly throughout the developmental stages of the 2 types of embryo and in the hermaphroditic gonads.</p> <p>Conclusion</p> <p>The accelerated evolutionary rates and very short and uniform intron may represent a part of <it>Dicyema </it>genomic features. The presence and expression of the two tool-kit genes (<it>Pax6 </it>and <it>Zic</it>) in <it>Dicyema </it>suggests that they can be very versatile genes even required for the highly reduced bilaterian like <it>Dicyema</it>. Dicyemids may be useful models of evolutionary body plan simplification.</p

Asymmetric Activation of the Primary Motor Cortex during Observation of a Mirror Reflection of a Hand

Mirror therapy is an effective technique for pain relief and motor function recovery. It has been demonstrated that magnetic 20-Hz activity is induced in the primary motor cortex (M1) after median nerve stimulation and that the amount of the stimulus-induced 20-Hz activity is decreased when the M1 is activated. In the present study, we investigated how the image or the mirror reflection of a hand holding a pencil modulates the stimulus-induced 20-Hz activity in the M1. Neuromagnetic brain activity was recorded from 13 healthy right-handed subjects while they were either viewing directly their hand holding a pencil or viewing a mirror reflection of their hand holding a pencil. The 20-Hz activity in the left or the right M1 was examined after the right or the left median nerve stimulation, respectively, and the suppression of the stimulus-induced 20-Hz in the M1 by viewing directly one hand holding a pencil or by viewing the mirror image of the hand holding a pencil was assumed to indicate the activation of the M1. The results indicated that the M1 innervating the dominant hand was suppressed either by viewing directly the dominant hand holding a pencil or by viewing the mirror image of the non-dominant hand holding a pencil. On the other hand, the M1 innervating the non-dominant hand was activated by viewing the mirror image of the dominant hand holding a pencil, but was not activated by viewing directly the non-dominant hand holding a pencil. The M1 innervating either the dominant or the non-dominant hand, however, was not activated by viewing the hand on the side ipsilateral to the M1 examined or the mirror image of the hand on the side contralateral to the M1 exaimined. Such activation of the M1 might induce some therapeutic effects of mirror therapy

Successful management of tracheo-innominate artery fistula with endovascular stent graft repair

AbstractTracheo-innominate artery fistula is a highly lethal complication after tracheostomy. A 37-year-old man who had undergone a tracheostomy 14 years earlier because of dysphagia after brain surgery had a tracheo-innominate artery fistula with exsanguinating hemorrhage from his tracheostomy site. After temporary control of the bleeding, a stent graft was implanted in the innominate artery through the brachial artery. The patient recovered uneventfully and remained well 14 months after the procedure, with no sign of infection. Endovascular stent grafting may be the treatment of choice for patients with tracheo-innominate artery fistula. (J Vasc Surg 2001;33:1280-2.

Near-Infrared Imaging Polarimetry of S106 Cluster-Forming Region with SIRPOL

We present the results of wide-field JHKs polarimetry toward the HII region S106 using the IRSF (Infrared Survey Facility) telescope. Our polarimetry data revealed an extended (up to ~ 5') polarized nebula over S106. We confirmed the position of the illuminating source of most of the nebula as consistent with S106 IRS4 through an analysis of polarization vectors. The bright portion of the polarized intensity is consistent with the red wing component of the molecular gas. Diffuse polarized intensity emission is distributed along the north--south molecular gas lanes. We found the interaction region between the radiation from S106 IRS4 and the dense gas. In addition, we also discovered two small polarization nebulae, SIRN1 and SIRN2, associated with a young stellar objects (YSO). Aperture polarimetry of point-like sources in this region was carried out for the first time. The regional magnetic field structures were derived using point-like source aperture polarimetry, and the magnetic field structure position angle around the cluster region in S106 was found to be ~ 120\arcdeg. The magnetic fields in the cluster region, however, have three type position angles: ~ 20\arcdeg, ~ 80\arcdeg, and ~ 120\arcdeg. The present magnetic field structures are consistent with results obtained by submillimeter continuum observations. We found that the magnetic field direction in the dense gas region is not consistent with that of the low density gas region.Comment: 22 pages, 11 figures, accepted for publication in A

Outflow and accretion detections in the young stellar object IRAS 04579+4703

We present Submillimeter Array observations of the young stellar object IRAS 04579+4703 in the 1.3 mm continuum and in the 12CO(2-1), 13CO(2-1) and C18O(2-1) lines. The 1.3 mm continuum image reveals a flattened structure with a mass of 13 Msun. The 12CO(2-1) line map and position-velocity (PV) diagram, together with the broad wing (full width=30 km/s of 12CO(2-1)) line, clearly show that there is an outflow motion, which originates from an embedded massive YSO in this region. The lengths of the blue-shifted and red-shifted lobes are 0.14 pc and 0.13 pc respectively. The total gas mass, average dynamical timescale and mass entrainment rate of the outflow are 1.8 Msun, 1.7*10^4 yr and 1.1*10^(-4) Msun/yr, respectively. The flattened morphology of the continuum source perpendicular to the outflow direction, and the velocity gradient seen in the spectra of C18O(2-1) taken from different locations along the major axis of the continuum source, suggest the presence of an accretion disk in this region.Comment: 4 pages, 4 figures, accepted by A&A Letter