Beyond the Required LISA Free-Fall Performance: New LISA Pathfinder Results down to 20 μHz

In the months since the publication of the first results, the noise performance of LISA Pathfinder has improved because of reduced Brownian noise due to the continued decrease in pressure around the test masses, from a better correction of noninertial effects, and from a better calibration of the electrostatic force actuation. In addition, the availability of numerous long noise measurement runs, during which no perturbation is purposely applied to the test masses, has allowed the measurement of noise with good statistics down to 20  μHz. The Letter presents the measured differential acceleration noise figure, which is at (1.74±0.05)  fm s^{-2}/sqrt[Hz] above 2 mHz and (6±1)×10  fm s^{-2}/sqrt[Hz] at 20  μHz, and discusses the physical sources for the measured noise. This performance provides an experimental benchmark demonstrating the ability to realize the low-frequency science potential of the LISA mission, recently selected by the European Space Agency.

Theoretical spectroscopic insights of tautomers and enantiomers of penicillamine

B3LYP and MP2 calculations have been carried out to investigate tautomers and enantiomers of penicillamine (Pen). Their infrared (IR), ultraviolet (UV), circular dichroism (CD) and nuclear magnetic resonance (NMR) spectra were obtained at linear-response, time-dependent DFT (TD-DFT). IR, UV and NMR spectra cannot be used to identify Pen enantiomers, showing nearly equal spectral profiles. CD spectra, however, give rise to completely symmetric signals, forming a perfect specular image to each other. Distinct CD profiles were also obtained for Pen tautomers. Important IR differences were found in positions and intensities of the vibrational stretching bands involving acid and amine groups of Pen tautomers. The highest electron transitions involving HOMO-LUMO orbitals show to be of major importance in the computed UV spectra, showing a large red-shift around 30nm as the zwitterionic and neutral Pen spectra are compared. NMR results show to be quite useful for identification of Pen tautomers since clear differences are found by means of the computed shielding tensors as well as spin-spin coupling constants ¹J(N,H) data.

Heparin Resistance During Surgical Resection of Inferior Vena Cava and Right Atrial Tumor Thrombus: A Case Report

Heparin resistance is the failure of unusually high doses of heparin to achieve a target activated clotting time (ACT). We present the case of a 47-year-old female patient, ASA 2, who was diagnosed with a neuroendocrine retroperitoneal tumor with thrombus in the left renal vein, inferior vena cava and right atrium. General and cardiothoracic surgeons collaborated to remove the tumor under cardiopulmonary bypass. Heparin resistance was considered and treated with 1000 UI of antithrombin III concentrate. The authors review the mechanisms and management of this entity.

Charge-Induced Force Noise on Free-Falling Test Masses: Results from LISA Pathfinder

We report on electrostatic measurements made on board the European Space Agency mission LISA Pathfinder. Detailed measurements of the charge-induced electrostatic forces exerted on free-falling test masses (TMs) inside the capacitive gravitational reference sensor are the first made in a relevant environment for a space-based gravitational wave detector. Employing a combination of charge control and electric-field compensation, we show that the level of charge-induced acceleration noise on a single TM can be maintained at a level close to 1.0  fm s^{-2} Hz^{-1/2} across the 0.1-100 mHz frequency band that is crucial to an observatory such as the Laser Interferometer Space Antenna (LISA). Using dedicated measurements that detect these effects in the differential acceleration between the two test masses, we resolve the stochastic nature of the TM charge buildup due to interplanetary cosmic rays and the TM charge-to-force coupling through stray electric fields in the sensor. All our measurements are in good agreement with predictions based on a relatively simple electrostatic model of the LISA Pathfinder instrument.

Sub-Femto-g Free Fall for Space-Based Gravitational Wave Observatories: LISA Pathfinder Results

We report the first results of the LISA Pathfinder in-flight experiment. The results demonstrate that two free-falling reference test masses, such as those needed for a space-based gravitational wave observatory like LISA, can be put in free fall with a relative acceleration noise with a square root of the power spectral density of 5.2±0.1  fm s^{-2}/sqrt[Hz], or (0.54±0.01)×10^{-15}  g/sqrt[Hz], with g the standard gravity, for frequencies between 0.7 and 20 mHz. This value is lower than the LISA Pathfinder requirement by more than a factor 5 and within a factor 1.25 of the requirement for the LISA mission, and is compatible with Brownian noise from viscous damping due to the residual gas surrounding the test masses. Above 60 mHz the acceleration noise is dominated by interferometer displacement readout noise at a level of (34.8±0.3)  fm/sqrt[Hz], about 2 orders of magnitude better than requirements. At f≤0.5  mHz we observe a low-frequency tail that stays below 12  fm s^{-2}/sqrt[Hz] down to 0.1 mHz. This performance would allow for a space-based gravitational wave observatory with a sensitivity close to what was originally foreseen for LISA.

Development of Chrysomya albiceps (Wiedemann) (Diptera: Calliphoridae) in different pig tissues

Chrysomya albiceps (Wiedemann) has been encountered breeding in animal carcasses and human bodies in many geographical regions. This species is considered an important postmortem indicator for Medical Legal Forensic Entomology. Studies have also demonstrated its capacity to develop in various natural and semi-synthetic substrates. The present study was undertaken to examine the development of immature C. albiceps in four different pig tissues. Eggs of this fly were deposited in flasks containing liver, abdominal fat, meat, and brain tissues. The flasks were maintained in an incubator at 25 ± 1°C, 70 ± 10% humidity, and 12-h/12-h photoperiod until emergence of the imagoes. Samples of the larvae were taken from different tissues/substrates to be weighed and measured. Their respective rates of development were accompanied. Comparisons among data from the different tissues indicated differences in the size and rate of development of larvae of the same age. Males emerged, on average, 1 day before females. Considerations as to the differences encountered for the estimate of postmortem interval were elaborated and consequences for the accuracy of the inferences discussed. The results indicate that such inferences should consider the disparities in the development of larvae presented by this species in different tissues.

Comparison of nutritional status assessment parameters in predicting length of hospital stay in cancer patients

BACKGROUND & AIMS

Undernutrition has been associated with an increased length of hospital stay which may reflect the patient prognosis. The aim of this study was to quantify and compare the association between nutritional status and handgrip strength at hospital admission with time to discharge in cancer patients.

METHODS

An observational prospective study was conducted in an oncology center. Patient-Generated Subjective Global Assessment, Nutritional Risk Screening 2002 and handgrip strength were conducted in a probabilistic sample of 130 cancer patients. The association between baseline nutritional status, handgrip strength and time to discharge was evaluated using survival analysis with discharge alive as the outcome.

RESULTS

Nutritional risk ranged from 42.3 to 53.1% depending on the tool used. According to Patient-Generated Subjective Global Assessment severe undernutrition was present in 22.3% of the sample. The association between baseline data and time to discharge was stronger in patients with low handgrip strength (adjusted hazard ratio, low handgrip strength: 0.33; 95% confidence interval: 0.19-0.55), compared to undernourished patients evaluated by the other tools; Patient-Generated Subjective Global Assessment: (adjusted hazard ratio, severe undernutrition: 0.45; 95% confidence interval: 0.27-0.75) and Nutritional Risk Screening 2002: (adjusted hazard ratio, with nutritional risk: 0.55; 95% confidence interval: 0.37-0.80).

CONCLUSIONS

An approximate 3-fold decrease in probability of discharge alive was observed in patients with low handgrip strength. Decreasing handgrip strength tertiles allowed to discriminate between patients who will have longer hospital stay, as well as undernutrition and nutritional risk assessed by Patient-Generated Subjective Global Assessment and Nutritional Risk Screening 2002.

Insects breeding in pig carrion in two environments of a rural area of the state of minas gerais, Brazil

The main objective of this study was to identify potential forensic indicators in the insect fauna associated with pig carrion and the pattern of insect succession during the decomposition process in two environments of a rural area in Uberlândia, State of Minas Gerais, Brazil. The study was conducted at two locations: in a pasture and in a fragment of a semi-deciduous forest (vegetation profile of the Cerrado biome) in two different seasons (rainy and dry) of 2010. The decomposition process was more rapid in the rainy season. More than 32,000 insects belonging to 17 species of 6 families of Diptera and 2 species of Coleoptera bred in the carcasses. The majority of Diptera bred in the first three stages of decomposition. However, Phoridae and Coleoptera bred mainly in the last two stages. The insects bred more abundantly in the pasture and in the humid season. The exceptions were the Fanniidae (Diptera), which bred more abundantly in the forest and the Dermestidae and Cleridae (Coleoptera), which did not demonstrate any preference in terms of environments and were more abundant in the dry season, respectively. Species such as Chrysomya albiceps (Wiedemann), Peckia (Patonella) intermutans (Walker), Necrobia rufipes (De Geer), and Dermestes maculatus (De Geer) may be potential indicators of post-mortem interval. Hemilucilia segmentaria (Fabricius) and Ophyra aenescens (Wiedemann) may be indicators of localization of the natural environment, while Musca domestica Linnaeus may be an indicator of the anthropic environment. The study thus presented many species of potential forensic indicators in rural areas of this region.

Susceptibilidade do besouro rola-bosta africano a reguladores de crescimento de insetos

Verificou-se a ação dos reguladores de crescimento de insetos (IGR), diflubenzuron e methoprene, sobre o besouro rola-bosta africano, Digitonthophagus gazella (Fabricius), um inimigo natural da mosca-dos-chifres, Haematobia irritans irritans (Linnaeus). Casais de besouros foram colocados em baldes contendo terra úmida e alimentados com fezes bovinas contendo 1, 0,5 ou 0,2ppm de diflubenzuron e 0,2ppm de methoprene. Os insetos e sua prole foram recuperados com o auxílio de armadilhas pitfall. Diflubenzuron e methoprene não afetaram a sobrevivência dos adultos inicialmente expostos, mas interferiram na produção de descendentes. Diflubenzuron, nas concentrações de 1 e 0,5ppm, também afetou a duração do ciclo de vida dos besouros. Nenhum dos IGRs alterou a razão sexual dos descendentes obtidos. As concentrações testadas de diflubenzuron mostraram-se moderadamente nocivas ao besouro enquanto methoprene a 0,2ppm mostrou ser pouco nocivo, segundo os critérios da International Organization for Biological Control.

Doença de Dupuytren. Revisão de 100 doentes operados

A Doença de Dupuytren observa-se com frequência nesta região. Dada a sua incidência, a diminuição da capacidade de trabalho que pode provocar e o elevado número de casos tratados cirurgicamente, decidimos reavaliar os pacientes, tentando identificar factores etiológicos e o resultado do tratamento.

Foi efectuado um estudo de revisão clínico e de registos em processo de 100 casos, operados entre Fevereiro de 2002 e Dezembro de 2005 no Serviço de Ortopedia do Hospital do Vale do Sousa.

Após discussão com os ortopedistas assistentes, todos os dados relevantes recolhidos foram tratados estatisticamente em colaboração com o Serviço de Bioestatística da Faculdade de Medicina do Porto.

Os resultados são precedidos de uma perspectiva histórica e um sumário da etiologia, evolução, estadiamento, classificação e opções de tratamento da doença de Dupuytren.

Mite allergen levels and acarologic analysis in house dust samples in Uberaba, Brazil

Mite allergen exposure has been widely related to sensitization and development of allergic diseases. This study intended to evaluate the degree of allergen exposure in Uberaba, Brazil, through the measurements of Der f 1 and Der p 1 allergen levels associated with the acarologic analysis in house dust samples. A total of 240 dust samples were collected from 60 houses through vacuuming sofas and bedding, during the months of March and July 2000. Indoor temperature and relative humidity were also measured. Mites were counted and identified under light microscopy and allergen levels were measured by two-site monoclonal antibody ELISAs. The major mite family was Pyroglyphidae (39.4%), having D. pteronyssinus as the most frequent species (15.6%), followed by D. farinae (12.3%) and E. maynei (7.9%). The family Glycyphagidae was less commonly found (4.8%), with Blomia tropicalis (4.4%) as its majoritary member. The highest levels of Der f 1 and Der p 1 allergens were found in bedding samples in March (31.7 and 0.9 microg/g of dust, respectively), with Der f 1 levels significantly higher than Der p 1 (p < 0.0001). There was a significant positive correlation between the mite number and allergen levels. These results indicate that Dermatophagoides sp are the most frequent mites in our region followed by E. maynei. Therefore, the knowledge of the local mite fauna would improve the means of investigating the association between allergen exposure and sensitization, allowing the addition of new mite extracts in diagnostic tests.

Peyronie's disease: surgical correction of 40 patients with relaxing incision and duramater graft

OBJECTIVE

Assessment of a long-term follow-up of a previously described technique to correct the curvature of the penis in Peyronie's disease.

MATERIAL AND METHODS

Forty patients (43-69 years old) were operated between 1989 and 1999. The eligibility criteria for surgery were: lesion stabilised during, at least, one year; angulation of 40 degrees or more; and difficult or impossible sexual intercourse. Moreover, the patients had to have good libido, maintained erections and interested sexual partners. The operative technique consisted in making an I-shaped relaxing incision in the zone of higher angulation of the tunica albuginea and the defect created in the tunica was covered with a human duramater graft.

RESULTS

The follow-up varied from 1 to 6 years (70%, > or =2 years). Cosmetic results: 95% good, 5% satisfactory (not needing further correction). Functional results: 85% good, 15% erectile dysfunction (10% moderate and 5% severe).

COMPLICATIONS

one recurrence, one partial necrosis of the foreskin, nine decreases in the sensibility of the glans (eight recovered after 4-12 months post-operatively).

CONCLUSIONS

The I-shaped relaxing incision and duramater graft procedure had a satisfactory success rate in the correction of severe Peyronie's disease. The utilisation of ready to use material (homo or hetero graft) avoids additional surgery, reduces the operative time and possible complications. Like in other procedures, the major problem of this surgery is the erectile dysfunction rate.

Incorporating knowledge-based biases into an energy-based side-chain modeling method: application to comparative modeling of protein structure

The performance of the self-consistent mean field theory (SCMFT) method for side-chain modeling, employing rotamer energies calculated with the flexible rotamer model (FRM), is evaluated in the context of comparative modeling of protein structure. Predictions were carried out on a test set of 56 model backbones of varying accuracy, to allow side-chain prediction accuracy to be analyzed as a function of backbone accuracy. A progressive decrease in the accuracy of prediction was observed as backbone accuracy decreased. However, even for very low backbone accuracy, prediction was substantially higher than random, indicating that the FRM can, in part, compensate for the errors in the modeled tertiary environment. It was also investigated whether the introduction in the FRM-SCMFT method of knowledge-based biases, derived from a backbone-dependent rotamer library, could enhance its performance. A bias derived from the backbone-dependent rotamer conformations alone did not improve prediction accuracy. However, a bias derived from the backbone-dependent rotamer probabilities improved prediction accuracy considerably. This bias was incorporated through two different strategies. In one (the indirect strategy), rotamer probabilities were used to reject unlikely rotamers a priori, thus restricting prediction by FRM-SCMFT to a subset containing only the most probable rotamers in the library. In the other (the direct strategy), rotamer energies were transformed into pseudo-energies that were added to the average potential energies of the respective rotamers, thereby creating hybrid energy-based/knowledge-based average rotamer energies, which were used by the FRM-SCMFT method for prediction. For all degrees of backbone accuracy, an optimal strength of the knowledge-based bias existed for both strategies for which predictions were more accurate than pure energy-based predictions, and also than pure knowledge-based predictions. Hybrid knowledge-based/energy-based methods were obtained from both strategies and compared with the SCWRL method, a hybrid method based on the same backbone-dependent rotamer library. The accuracy of the indirect method was approximately the same as that of the SCWRL method, but that of the direct method was significantly higher.

Implicit solvation in the self-consistent mean field theory method: sidechain modelling and prediction of folding free energies of protein mutants

The Atomic Solvation Parameter (ASP) model is one of the simplest models of solvation, in which the solvation free energy of a molecule is proportional to the solvent accessible surface area (SAS) of its atoms. However, until now this model had not been incorporated into the Self-Consistent Mean Field Theory (SCMFT) method for modelling sidechain conformations in proteins. The reason for this is that SAS is a many-body quantity and, thus, it is not obvious how to define it within the Mean Field (MF) framework, where multiple copies of each sidechain exist simultaneously. Here, we present a method for incorporating an SAS-based potential, such as the ASP model, into SCMFT. The theory on which the method is based is exact within the MF framework, that is, it does not depend on a pairwise or any other approximation of SAS. Therefore, SAS can be calculated to arbitrary accuracy. The method is computationally very efficient: only 7.6% slower on average than the method without solvation. We applied the method to the prediction of sidechain conformation, using as a test set high-quality solution structures of 11 proteins. Solvation was found to substantially improve the prediction accuracy of well-defined surface sidechains. We also investigated whether the methodology can be applied to prediction of folding free energies of protein mutants, using a set of barnase mutants. For apolar mutants, the modest correlation observed between calculated and observed folding free energies without solvation improved substantially when solvation was included, allowing the prediction of trends in the folding free energies of this type of mutants. For polar mutants, correlation was not significant even with solvation. Several other factors also responsible for the correlation were identified and analysed. From this analysis, future directions for applying and improving the present methodology are discussed.

Evolution of the thyroid hormone-binding protein, transthyretin

Transthyretin (TTR) belongs to a group of proteins, which includes thyroxine-binding globulin and albumin, that bind to and transport thyroid hormones in the blood. TTR is also indirectly implicated in the carriage of vitamin A through the mediation of retinol-binding protein (RBP). It was first identified in 1942 in human serum and cerebrospinal fluid and was formerly called prealbumin for its ability to migrate faster than serum albumin on electrophoresis of whole plasma. It is a single polypeptide chain of 127 amino acids (14,000 Da) and is present in the plasma as a tetramer of noncovalently bound monomers. The major sites of synthesis of TTR in eutherian mammals, marsupials, and birds are the liver and choroid plexus but in reptiles it is synthesised only in the choroid plexus. The observation that TTR is strongly expressed in the choroid plexus but not in the liver of the stumpy-tailed lizard and the strong conservation of expression in the choroid plexus from reptiles to mammals have been taken as evidence to suggest that extrahepatic synthesis of TTR evolved first. The identification and cloning of TTR from the liver of an amphibian, Rana catesbeiana, and a teleost fish, Sparus aurata, and its absence from the choroid plexus of both species suggest an alternative model for its evolution. Protein modelling studies are presented that demonstrate differences in the electrostatic characteristics of the molecule in human, rat, chicken, and fish, which may explain why, in contrast to TTR from human and rat, TTR from fish and birds preferentially binds triiodo-l-thyronine.

Latin american experience with two low-dose oral contraceptives containing 30 microg ethinylestradiol/75 microg gestodene and 20 microg ethinylestradiol/150 microg desogestrel

The objective of this study was to compare cycle control, efficacy and tolerance of an oral contraceptive containing 20 microg ethinylestradiol and 150 microg desogestrel with a preparation containing 30 microg ethinylestradiol combined with 75 microg gestodene. This study involved 342 women and 4104 cycles use in Argentina, Brazil, Chile, and Mexico. Contraceptive efficacy was good with both formulations. Two pregnancies occurred in the desogestrel group but were not due to method failure. With respect to cycle control, the incidence of intermenstrual bleeding was higher during the first 3 cycles in the desogestrel group; it was significant (p <0.01) during the first 3 days of the cycle for a normal or heavy bleeding only in the Mexican group. Amenorrhea was not reported for any group, but the incidence of dysmenorrhea was significantly higher (p <0.01) in the Brazilian desogestrel group (13.8%) and was significantly lower (p <0.01) in the Mexican gestodene group (8.5%). Adverse events were similar in all the countries with headache, breast tension, and nausea, the most frequently reported symptoms. The range of mean increase in body weight varied from 0.2 kg in the Argentine group to 2.6 kg in the Chilean group (95% confidence limit, +/- 2.51) in the gestodene group, and 0.2 kg in the Argentine group to 2.5 kg in Brazilian group (95% confidence limit, +/- 2.36) in the desogestrel group. Fifteen women discontinued because of headache, but there were no significant differences between the groups regarding discontinuation for this and other medical or non-medical reasons. Both oral contraceptive preparations are reliable and well tolerated, and both have favorable effects on control cycle.

[Comparative study of Toronto SPV prosthesis and bileaflet mechanical aortic prosthesis with 2D-Doppler echocardiography]

AIM

The aim of this study was to make a noninvasive comparison, by means of Doppler echocardiography, of the hemodynamic performance of biological stentless xenografts and mechanical bileaflet (MB) prostheses (P) in aortic position.

METHODS

We studied 20 patients (pts) with normofunctional (nf) aortic Toronto (T) Stentless Porcine valves (SPV)--Group I--8 males, aged 69 +/- 12 years, 32 +/- 9 months after surgery, and 30 pts with nf MB aortic P (Carbomedics or St. Jude Medical)--Group II--17 males (p = NS vs G I), aged 61 +/- 12 years (p < 0.01 vs G I), 30 +/- 12 months after implantation (p = NS vs G I). Both groups were comparable with regard to body surface area and surgical indication. P diameters ranged from 21 to 25 mm (G I: 22.9 +/- 1.7; G II: 22.8 +/- 1.7 - p = NS), the number of pts with the same P diameter in each group being similar. We analysed, at rest: aortic orifice diameter (AoOd - cm), maximal (GMax) and mean (GMean) transprosthesic pressure gradients, P functional area (PFA) and P resistance (PRes). Gradients (mm Hg) were calculated by means of the Bernoulli equation, PFA (cm2) by means of the continuity equation and PRes (dynes.s.cm-5) as 1333 x Gmean x SEP/SV (SEP = systolic ejection period; SV = stroke volume).

RESULTS

AoOd (G I vs G II): P 21--1.78 +/- 0.04 vs 2.00 +/- 0.10 (p < 0.001); P 23--1.91 +/- 0.10 vs 2.19 +/- 0.10 (p = 0.01); P 25--2.22 +/- 0.24 vs 2.29 +/- 0.19 (NS). Doppler parameters: [table: see text]

CONCLUSIONS

P T SPV show better hemodynamic performance when compared to P MB with the same diameter, in aortic position. In addition, our results suggest that P T SPV allow the use of larger valve sizes for the same aortic orifice diameter.