Anomalous couplings of the third generation in rare B decays

We study the potential effects of anomalous couplings of the third generation quarks to gauge bosons in rare B decays. We focus on the constraints from flavor changing neutral current processes such as b→sγ and b →sl+l-. We consider both dimension-four and dimension-five operators and show that the latter can give large deviations from the standard model in the still unobserved dilepton modes, even after the bounds from b→sγ and precision electroweak observables are taken into account. ©2000 The American Physical Society.

Nephron-sparing surgery for treatment of reninoma: a rare renin secreting tumor causing secondary hypertension

A 25-year-old hypertensive female patient was referred to our institution. Initial workup exams demonstrated a 2.8 cm cortical lower pole tumor in the right kidney. She underwent laparoscopic partial nephrectomy without complications. Histopathologic examination revealed a rare juxtaglomerular cell tumor known as reninoma. After surgery, she recovered uneventfully and all medications were withdrawn. Case hypothesis: Secondary arterial hypertension is a matter of great interest to urologists and nephrologists. Renovascular hypertension, primary hyperadosteronism and pheocromocytoma are potential diagnosis that must not be forgotten and should be excluded. Although rare, chronic pyelonephritis and renal tumors as rennin-producing tumors, nephroblastoma, hypernephroma, and renal cell carcinoma might also induce hypertension and should be in the diagnostic list of clinicians. Promising future implications: Approximately 5% of patients with high blood pressure have specific causes and medical investigation may usually identify such patients. Furthermore, these patients can be successfully treated and cured, most times by minimally invasive techniques. This interesting case might expand knowledge of physicians and aid better diagnostic care in future medical practice.

Proteomic analysis of the rare Uracoan rattlesnake Crotalus vegrandis venom: evidence of a broad arsenal of toxins

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Pulmonary artery sarcoma: a rare disease

Pulmonary artery sarcomas (PAS) are rare and probably incurable tumours. The clinical manifestations are non-specific and very similar to that of patients with thromboembolic disease, resulting in delay of the correct diagnosis and proper treatment. We report the case of a 66-year-old woman with PAS diagnosed by computed tomography guided biopsy. Chemotherapy treatment was initiated but the patient died 11 months after diagnosis.

Atypical calcified ganglioglioma: a rare case report

Considered rare tumors, gangliogliomas account for 0.4% - 0.9% of intracranial neoplasms. The peak of its incidence occurs between 10 and 20 years of age. These tumors are composed of glial and ganglion cells and they are relatively low-grade neoplasms associated with good prognoses. We report a case of an atypical calcified ganglioglioma in an 18-year-old woman with history of four months of stabbing right-sided parietal headache, paroxysmal. On image studies were noted the presence of thick wall calcification in gangliogliomas. Although rare, this atypical ganglioglioma should be included in the differential diagnosis of lesions occurring in this area of the brain.

Cytological result of in situ ductal carcinoma in nipple discharge: a rare diagnosis

Background: More than half of women present nipple discharge during reproductive age. Case: This case is about a 36 years old woman with unilateral spontaneous hyaline nipple discharge associated with breast pain. The study of scintimammography was compatible with multifocal proliferative lesion in situ. It was performed cytological smear of nipple discharge. It was paucicellular smear represented by cluster of ductal cells in three-dimensional design with hyperchromatic nuclei in the presence of myoepithelial cells. Red cells and signs of necrosis were not observed. The diagnosis of in situ ductal carcinoma was confirmed in biopsy and mastectomy specimen through the expression of calponin in myoepithelial cells at immunohistochemistry. It is known that the cytological examination of nipple discharge has low sensitivity and specificity. However, it is an easy and inexpensive procedure. Suspicious or positive results, may be important for guidance workup of patients in order to perform earlier diagnosis of malignancy. Conclusion: this case demonstrates that in situ ductal carcinoma can be characterized by positive nipple discharge, and cytology sample is an important tool for the diagnosis of suspicion of malignancy and further diagnostic investigation.

HIGH TEMPERATURE RARE EARTH COMPOUNDS: SYNTHESIS, CHARACTERIZATION AND APPLICATIONS IN DEVICE FABRICATION

As the area of nanotechnology continues to grow, the development of new nanomaterials with interesting physical and electronic properties and improved characterization techniques are several areas of research that will be remain vital for continued improvement of devices and the understanding in nanoscale phenomenon. In this dissertation, the chemical vapor deposition synthesis of rare earth (RE) compounds is described in detail. In general, the procedure involves the vaporization of a REClx (RE = Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho) in the presence of hydride phase precursors such as decaborane and ammonia at high temperatures and low pressures. The vapor-liquid-solid mechanism was used in combination with the chemical vapor deposition process to synthesize single crystalline rare earth hexaboride nanostructures. The crystallographic orientation of as-synthesized rare earth hexaboride nanostructures and gadolinium nitride thin films was controlled by judicious choice of specific growth substrates and modeled by analyzing x-ray diffraction powder patterns and crystallographic models. The rare earth hexaboride nanostructures were then implemented into two existing technologies to enhance their characterization capabilities. First, the rare earth hexaboride nanowires were used as a test material for the development of a TEM based local electrode atom probe tomography (LEAP) technique. This technique provided some of the first quantitative compositional information of the rare earth hexaboride systems. Second, due to the rigidity and excellent conductivity of the rare earth hexaborides, nanostructures were grown onto tungsten wires for the development of robust, oxidation resistant nanomanipulator electronic probes for semiconductor device failure analysis.

Convergent Adaptations: Bitter Manioc Cultivation Systems in Fertile Anthropogenic Dark Earths and Floodplain Soils in Central Amazonia

Shifting cultivation in the humid tropics is incredibly diverse, yet research tends to focus on one type: long-fallow shifting cultivation. While it is a typical adaptation to the highly-weathered nutrient-poor soils of the Amazonian terra firme, fertile environments in the region offer opportunities for agricultural intensification. We hypothesized that Amazonian people have developed divergent bitter manioc cultivation systems as adaptations to the properties of different soils. We compared bitter manioc cultivation in two nutrient-rich and two nutrient-poor soils, along the middle Madeira River in Central Amazonia. We interviewed 249 farmers in 6 localities, sampled their manioc fields, and carried out genetic analysis of bitter manioc landraces. While cultivation in the two richer soils at different localities was characterized by fast-maturing, low-starch manioc landraces, with shorter cropping periods and shorter fallows, the predominant manioc landraces in these soils were generally not genetically similar. Rather, predominant landraces in each of these two fertile soils have emerged from separate selective trajectories which produced landraces that converged for fast-maturing low-starch traits adapted to intensified swidden systems in fertile soils. This contrasts with the more extensive cultivation systems found in the two poorer soils at different localities, characterized by the prevalence of slow-maturing high-starch landraces, longer cropping periods and longer fallows, typical of previous studies. Farmers plant different assemblages of bitter manioc landraces in different soils and the most popular landraces were shown to exhibit significantly different yields when planted in different soils. Farmers have selected different sets of landraces with different perceived agronomic characteristics, along with different fallow lengths, as adaptations to the specific properties of each agroecological micro-environment. These findings open up new avenues for research and debate concerning the origins, evolution, history and contemporary cultivation of bitter manioc in Amazonia and beyond.

PbO-GeO2 rare earth doped glasses with silver nanoparticles as materials for IR laser triggers

We have shown the possibility of operation by the piezooptical response of PbO-GeO2 glasses doped with rare earth ions and silver nanoparticles by illumination of double frequency CO2 nanosecond laser. Substantial influence of thermoannealing on the output photoinduced elastooptical susceptibilities was established. The effect is very sensitive to temperature and to the corresponding tensor components. The effect of thermoannealing leads to enhanced long-range ordering with the occurrence of corresponding trapping levels within the forbidden gaps. The discovered effects may be used for creation of low-temperature IR laser triggers.

Biliary tract schwannoma: A rare cause of obstructive jaundice in a young patient

Schwannoma is a tumor derived from Schwann cells which usually arises in the upper extremities, trunk, head and neck, retroperitoneum, mediastinum, pelvis, and peritoneum. However, it can arise in the gastrointestinal tract, including biliary tract. We present a 24-year-old male patient with obstructive jaundice, whose investigation with computed tomography abdomen showed focal wall thickening in the common hepatic duct, difficult to differentiate with hilar adenocarcinoma. He was diagnosed intraoperatively schwannoma of common bile duct and treated with local resection. The patient recovered well without signs of recurrence of the lesion after 12 mo. We also reviewed the common bile duct schwannoma related in the literature and evaluated the difficulty in pre and intraoperative differential diagnosis with adenocarcinoma hilar. Resection is the treatment of choice for such cases and the tumor did not recur in any of the resected cases. (C) 2012 Baishideng. All rights reserved.

The remarkable solar twin HIP 56948: a prime target in the quest for other Earths

Context. The Sun shows abundance anomalies relative to most solar twins. If the abundance peculiarities are due to the formation of inner rocky planets, that would mean that only a small fraction of solar type stars may host terrestrial planets. Aims. In this work we study HIP 56948, the best solar twin known to date, to determine with an unparalleled precision how similar it is to the Sun in its physical properties, chemical composition and planet architecture. We explore whether the abundances anomalies may be due to pollution from stellar ejecta or to terrestrial planet formation. Methods. We perform a differential abundance analysis (both in LTE and NLTE) using high resolution (R similar to 100 000) high S/N (600-650) Keck HIRES spectra of the Sun (as reflected from the asteroid Ceres) and HIP 56948. We use precise radial velocity data from the McDonald and Keck observatories to search for planets around this star. Results. We achieve a precision of sigma less than or similar to 0.003 dex for several elements. Including errors in stellar parameters the total uncertainty is as low as sigma similar or equal to 0.005 dex (1%), which is unprecedented in elemental abundance studies. The similarities between HIP 56948 and the Sun are astonishing. HIP 56948 is only 17 +/- 7 K hotter than the Sun, and log g, [Fe/H] and microturbulence velocity are only +0.02 +/- 0.02 dex, +0.02 +/- 0.01 dex and +0.01 +/- 0.01 km s(-1) higher than solar, respectively. Our precise stellar parameters and a differential isochrone analysis shows that HIP 56948 has a mass of 1.02 +/- 0.02 M-circle dot and that it is similar to 1 Gyr younger than the Sun, as constrained by isochrones, chromospheric activity, Li and rotation. Both stars show a chemical abundance pattern that differs from most solar twins, but the refractory elements (those with condensation temperature T-cond greater than or similar to 1000 K) are slightly (similar to 0.01 dex) more depleted in the Sun than in HIP 56948. The trend with T-cond in differential abundances (twins -HIP 56948) can be reproduced very well by adding similar to 3 M-circle plus of a mix of Earth and meteoritic material, to the convection zone of HIP 56948. The element-to-element scatter of the Earth/meteoritic mix for the case of hypothetical rocky planets around HIP 56948 is only 0.0047 dex. From our radial velocity monitoring we find no indications of giant planets interior to or within the habitable zone of HIP 56948. Conclusions. We conclude that HIP 56948 is an excellent candidate to host a planetary system like our own, including the possible presence of inner terrestrial planets. Its striking similarity to the Sun and its mature age makes HIP 56948 a prime target in the quest for other Earths and SETI endeavors.

Endophthalmitis: A Rare but Devastating Metastatic Bacterial Complication of Hemodialysis Catheter-Related Sepsis

There are many infectious complications related to vascular access in patients undergoing maintenance hemodialysis. We report two cases of endophthalmitis as a metastatic infection associated with a tunneled catheter and a temporary dual lumen catheter. Both patients were diabetic. A 61-year-old female on maintenance hemodialysis by a jugular tunnelized catheter during the past year was receiving parenteral antibiotics for catheter salvage due to fever episodes in the last 3 months. She was admitted to the hospital presenting pain, proptosis, conjunctival hyperemia, corneal infiltrate, and visual acuity of no light perception (NLP). A 51-year-old male recently undergoing hemodialysis by a temporary dual lumen catheter presented fever. His catheter was removed, but he was admitted to the hospital presenting fever, decreased vision, edema, and pain in his left eye. On examination, eyelid edema, conjunctival hyperemia, purulent secretion, hypopyon in the pupils, and visual acuity of NLP were verified. A diagnosis of endogenous endophthalmitis was made in both patients on clinical grounds and computed tomography. Evisceration of the left eye was the first option of treatment for both patients due to poor vision. Cultures of the eviscerated ocular globes showed Staphylococcus hemolyticus and Staphylococcus aureus, respectively. After evisceration, both patients received treatment, had a good outcome, and were discharged to continue their hemodialysis program. Metastatic bacterial endophthalmitis is a rare complication of dialysis catheter-related bacteremia. When suspected, urgent ophthalmologic evaluation and treatment are needed to reduce the risk of losing vision in the affected eye.

Multiple Tooth Agenesis in Non-syndromic Patient: a rare case report

Dental agenesis is a term referred to the absence of one or more teeth. However, oligodontia is a severe type of tooth agenesis involving six or more congenitally missing teeth, excluding the third molars. Oligodontia has a low prevalence and is a very rare condition. The aim was to show this case report of a 13-year-old female patient who presented oligodontia with absence of eight permanent teeth and condylar atrophy on left side. The patient had no history of any syndrome or systemic disease according to the anamnesis. Is very important to know oligodontia features to perform a carefully treatment plan.

A rare case of iatrogenic gingival Kaposi's sarcoma

Kaposi's sarcoma is an angioproliferative tumour rarely found in the oral cavity. We present the 3rd case of iatrogenic gingival Kaposi's sarcoma reported in the English-language literature which developed in a young patient 5 years after a renal transplant and discuss their histological features and differential diagnosis. (c) 2011 European Association for Cranio-Maxillo-Facial Surgery.