Bibliographic and Technical Problems in Implementing a National Library Network

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On the Connectedness of the Moduli Space of Calabi--Yau Manifolds

We show that the moduli space of all Calabi-Yau manifolds that can be realized as hypersurfaces described by a transverse polynomial in a four dimensional weighted projective space, is connected. This is achieved by exploiting techniques of toric geometry and the construction of Batyrev that relate Calabi-Yau manifolds to reflexive polyhedra. Taken together with the previously known fact that the moduli space of all CICY's is connected, and is moreover connected to the moduli space of the present class of Calabi-Yau manifolds (since the quintic threefold P_4[5] is both CICY and a hypersurface in a weighted P_4, this strongly suggests that the moduli space of all simply connected Calabi-Yau manifolds is connected. It is of interest that singular Calabi-Yau manifolds corresponding to the points in which the moduli spaces meet are often, for the present class, more singular than the conifolds that connect the moduli spaces of CICY's.Comment: 22 pages plain TeX, Tables and references adde

Lingual Thyroid Ectopia: Diagnostic SPECT/CT Imaging and Radioactive Iodine Treatment

Background: Lingual thyroid is a rare abnormality of thyroid development that is usually treated conservatively with levothyroxine replacement. Rarely, it becomes large enough to cause obstructive symptoms in the oral cavity, requiring definitive treatment. Patient Findings: This study reports on three patients with lingual thyroid treated with radioactive iodine-131 (131I) with successful radioablation of their ectopic thyroid tissues. Measurement of 24-hour radioactive iodine uptake within thyroidal tissues and hybrid single-photon emission computed tomography/computed tomography imaging using either iodine-123 or technetium-99m pertechnetate scans were performed in all patients demonstrating the location and size of lingual thyroid and absence of an orthotopic thyroid gland. Summary: The aim of this study was to describe nonsurgical management of obstructive lingual thyroid tissue with 131I therapy for lingual thyroid radioablation. Patients were prepared with a low-iodine diet and levothyroxine withdrawal prior to radioablation for optimizing 131I uptake in ectopic thyroid tissues. Hybrid single-photon emission computed tomography/computed tomography measurement of anatomic size of lingual thyroid tissue and radioactive iodine uptake guided the selection of therapeutic doses, resulting in administration of 10.7, 17.5, and 15.4 mCi of 131I, respectively. There were no post-therapy complications, and clinical follow-up demonstrated resolution of obstructive oropharyngeal symptoms. Conclusions: Ectopic lingual thyroid tissue is rarely associated with obstructive oropharyngeal symptoms due to progressive enlargement. Radioiodine therapy with 131I is an effective treatment modality for ablation of ectopic thyroid tissue as an alternative to surgery.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140270/1/thy.2015.0396.pd

Efficacy of radioactive iodine treatment of graves’ hyperthyroidism using a single calculated 131I dose

Abstract Objective To evaluate the success rate of therapeutic administration of a single calculated 131I activity for eliminating hyperthyroidism due to Graves’ disease. Methods and materials Patients with Graves’ hyperthyroidism underwent pinhole thyroid imaging, 24-h radioactive iodine uptake (RAIU) measurements and clinical examination and received a calculated 131I activity of 0.2 mCi per estimated gram of thyroid tissue, adjusted for the 24-h RAIU. The goal of RAI treatment was to achieve hypothyroidism within 3–6 months of 131I administration. Response to RAI therapy was assessed at 7 weeks and 3 months by clinical and biochemical follow-up. Results The study included 316 hyperthyroid patients with Graves’ disease (F238:M78, mean age 42.1 ± 16 y, 4–94). 179 patients (56.6%) had no prior therapeutic intervention (treatment-naive patients), whereas 6 patients had prior thyroid surgery, and 131 (41.5%) had been treated with anti-thyroid medications. The mean estimated thyroid gland size was 50.2 g ± 18, range 15–100. Mean RAIU was 0.57 ± 0.17 (normal 0.07–0.30). RAI doses ranged from 5 to 70 mCi (mean dose = 18.1 mCi). Successful treatment of hyperthyroidism at our institution was obtained after a single therapeutic 131-I activity administration in 295 of 316 (93.3%) patients. Multivariate logistic regression analysis demonstrated that failure of 131I therapy was associated with previous PTU therapy (p <  0.001). The mean response time after successful RAI therapy was 110.2 days, with cumulative response of 25% at 61 days, 50% by 84 days and 75% by 118 days after radioiodine administration. The mean time to respond for those on prior PTU medications was 297 days compared to 116 days for those on MMI and 109 days for those not previously treated with antithyroid medications. In patients with persistent hyperthyroidism, failure of RAI therapy was documented in 16 patients (76.2%) within (less than) one year after 131I administration and in 5 patients (23.8%) more than one year after initial therapy, considered late failure. Conclusion Successful 131I therapy for Graves’ hyperthyroidism with a single calculated dose can be achieved in the majority (> 90%) of patients, adjusting for the thyroid size and 24 h uptake measurement.https://deepblue.lib.umich.edu/bitstream/2027.42/146543/1/40842_2018_Article_71.pd

Investigations on the Luminescence Properties of Quartz and Feldspars Extracted from Loess in the Canterbury Plains, New Zealand South Island

The applicability of the single-aliquot regenerative-dose (SAR) protocol, by using the optically stimulated lumi-nescence (OSL) signal of quartz as well as the post-infrared–infrared (pIRIR) signals of polymineral fine grains, namely pIRIR225 and pIRIR290, was assessed for dating loess in New Zealand South Island. OSL signals of quartz grains displayed low sensitivity. However, the application of repeated irradiation/bleaching cycles did not result in an increase in sensitivity; annealing in the 300–500°C temperature range generated the sensitisation of both the 110°C thermoluminescence (TL) peak as well as the OSL signal, likely by activation of yet unidentified luminescence centres. After heating, the quartz signal is comparable to that of ideal samples, but the annealing is precluding successful dating. On the other hand, feldspar infrared-stimulated signals displayed satisfactory properties, al-lowing estimation of ages ranging from 14 ± 1–29 ± 3 ka for the investigated deposit. It was shown that pIRIR225 and pIRIR290 methods have potential for dating loess in the South Island of New Zealand, based on the following observations: (i) Dose recovery tests were successful with recovered-to-given dose ratios with a <10% deviation from unity, (ii) constant residual values of about 4 Gy and about 10 Gy were obtained after exposures for 48 h in the case of pIRIR225 signals and 96 h in the case of pIRIR290 signals, respectively, (iii) while a slight dose-dependence of the residual was reported, and for a dose as large as 1600 Gy the residual values are ≅9 Gy and ≅19 Gy for pIRIR225 and pIRIR290 signals, respectively

On Semi-Periods

The periods of the three-form on a Calabi-Yau manifold are found as solutions of the Picard-Fuchs equations; however, the toric varietal method leads to a generalized hypergeometric system of equations which has more solutions than just the periods. This same extended set of equations can be derived from symmetry considerations. Semi-periods are solutions of this extended system. They are obtained by integration of the three-form over chains; these chains can be used to construct cycles which, when integrated over, give periods. In simple examples we are able to obtain the complete set of solutions for the extended system. We also conjecture that a certain modification of the method will generate the full space of solutions in general.Comment: 18 pages, plain TeX. Revised derivation of $\Delta^*$ system of equations; version to appear in Nuclear Physics

Qualitative Assessment of the White Wine Varieties Grown in Dealu Bujorului Vineyard, Romania

Ecoclimatic conditions have a great influence on grapevine growth and development. Favourable conditions (solar radiation, temperature, humidity etc.) are important and have a positive effect on the growth and fruition. Critical conditions have negative influences resulting in low grape production and wine quality. The purpose of this research was to analyse the quality of wine obtained from eight grapevine varieties (four Romanian autochthonous varieties: ‘Feteasca regala’, ‘Feteasca alba’, ‘Babeasca gri’, ‘Sarba’, and four world-wide varieties: ‘Aligoté’, ‘Sauvignon Blanc’, ‘Muscat Ottonel’, and ‘Italian Riesling’). The wine samples were obtained from micro-wine production under local weather conditions of Dealu Bujoruluivineyard, Romania. The physico-chemical analysis of young wines showed that the highest alcohol content was recorded at the ‘Sauvignon blanc’ variety (14.35% vol.) followed by ‘Sarba’ (14.10% vol.). The highest level of acidity was registered to ‘Babeasca gri’ (5.90 g/L C4H6O6) and the lowest acidity in the ‘Muscat Ottonel’ wine (4.40 g/L C4H6O6). The pH values were between limits of 3.62 (‘Feteasca alba’) and 3.27 (‘Aligote’). In order to get a wider perspective about the wine quality, another 11 parameters were examined at these varieties, using spectrophotometric methods (acetic acid, potassium, calcium, free amino nitrogen, tartaric acid, copper, L-lactic acid, iron, L-malic acid, D-gluconic acid and glycerol). The results showed the suitability of ecoclimatic conditions and the proper growth and development of the tested varieties for obtaining wines withsuperiors quality

Minimally invasive approach to colorectal tumors - 3 years of experience in a private hospital

Spitalul Privat ”Sanador”, București, România, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Abordul minim invaziv al tumorilor colo-rectale reprezintă o preocupare a colectivului Spitalului privat Sanador, în pofida adresabilității crescute a cancerelor în stadii avansate, procentul acestora din totalul intervențiilor chirurgicale pentru această patologie rămânând constant, printr-o atentă selecție a pacienților, care sa beneficieze de avantajele laparoscopiei. Material și metode: Studiul prezent analizează intervențiile chirurgicale pentru tumori colo-rectale efectuate între anii 2016-2018 în Spitalul Sanador București. Din totalul de 214 intervenții chirurgicale pentru patologia colo-rectală, 41 au fost prin abord minim invaziv, reprezentând procentual 20% din totalul intervențiilor pentru această patologie, procentul fiind constant în fiecare din acești ani: 2016 – 13 intervenții prin abord minim invaziv din totalul de 68 (19.11%); 2017 – 17 intervenții prin abord minim invaziv din totalul de 79 (21.5%); 2018 – 11 intervenții chirurgicale prin abord minim invaziv dintr-un total de 57 (19.3%). Rezultate: Cele mai frecvente localizări ale tumorilor pentru care indicația a fost de abord minim invaziv, au fost cele recto-sigmoidiene (28). Selecția pacienților s-a facut după stadializarea preoperatorie, admitându-se ca și abord laparoscopic tumori T1, T2, T3, în rare cazuri T4. În cazul tumorilor avansate, substadializate preoperator, s-a tentat efectuarea a cât mai multor timpi din cadrul rezecției, prin abord minim invaziv, iar cazurile in care anastomozele au fost efectuate extracorporeal nu au fost interpretate ca și conversie. Concluzii: Rezultatele bune se înscriu în rândul celor ale centrelor cu volum și experiența mari în abordarea minim invazivă a tumorilor colo-rectale și constituie premize pentru creșterea procentului de astfel de intervenții în clinica noastră.Introduction: The minimally invasive approach of colorectal tumors is a concern of the Sanador private hospital team, despite the increased addressability of cancers in advanced stages, their percentage of total surgical interventions for this pathology remaining constantly through a careful selection of patients who benefit from the advantages of laparoscopy. Material and methods: The present study examines surgical interventions for colorectal tumors performed between 2016-2018 at Sanador Hospital Bucharest. Of the total of 214 surgical procedures for rectal pathology, 41 were by minimally invasive approach, accounting for 20% of all interventions for this pathology, the percentage being constant in each of these years: 2016-13 interventions through the minimally invasive approach of the total of 68 (19.11%); 2017 - 17 interventions through minimally invasive approach from the total of 79 (21.5%); 2018 - 11 minimally invasive surgical interventions from a total of 57 (19.3%). Results: The most common tumor localizations for which the indication was minimally invasive were the recto-sigmoid (28). Selection of patients was made after preoperative staging, admitting as a laparoscopic approach T1, T2, T3 tumors, in rare cases T4. In the case of advanced tumors, pre-operative substations, it was tempting to perform as many times as possible in the resection through a minimally invasive approach, and the cases in which the anastomoses were performed extracorporeally were not interpreted as conversion. Conclusions: Good results are among those with large volume centers and great experience in the minimally invasive approach of colorectal tumors and are prerequisites for increasing the percentage of such interventions in our clinic