Avalanche-Induced Current Enhancement in Semiconducting Carbon Nanotubes

Semiconducting carbon nanotubes under high electric field stress (~10 V/um) display a striking, exponential current increase due to avalanche generation of free electrons and holes. Unlike in other materials, the avalanche process in such 1D quantum wires involves access to the third sub-band, is insensitive to temperature, but strongly dependent on diameter ~exp(-1/d^2). Comparison with a theoretical model yields a novel approach to obtain the inelastic optical phonon emission length, L_OP,ems ~ 15d nm. The combined results underscore the importance of multi-band transport in 1D molecular wires

First Weak-lensing Results from "See Change": Quantifying Dark Matter in the Two Z>1.5 High-redshift Galaxy Clusters SPT-CL J2040-4451 and IDCS J1426+3508

We present a weak-lensing study of SPT-CLJ2040-4451 and IDCSJ1426+3508 at z=1.48 and 1.75, respectively. The two clusters were observed in our "See Change" program, a HST survey of 12 massive high-redshift clusters aimed at high-z supernova measurements and weak-lensing estimation of accurate cluster masses. We detect weak but significant galaxy shape distortions using IR images from the WFC3, which has not yet been used for weak-lensing studies. Both clusters appear to possess relaxed morphology in projected mass distribution, and their mass centroids agree nicely with those defined by both the galaxy luminosity and X-ray emission. Using an NFW profile, for which we assume that the mass is tightly correlated with the concentration parameter, we determine the masses of SPT-CL J2040-4451 and IDCS J1426+3508 to be M_{200}=8.6_{-1.4}^{+1.7}x10^14 M_sun and 2.2_{-0.7}^{+1.1}x10^14 M_sun, respectively. The weak-lensing mass of SPT-CLJ2040-4451 shows that the cluster is clearly a rare object. Adopting the central value, the expected abundance of such a massive cluster at z>1.48 is only ~0.07 in the parent 2500 sq. deg. survey. However, it is yet premature to claim that the presence of this cluster creates a serious tension with the current LCDM paradigm unless that tension will remain in future studies after marginalizing over many sources of uncertainties such as the accuracy of the mass function and the mass-concentration relation at the high mass end. The mass of IDCSJ1426+3508 is in excellent agreement with our previous ACS-based weak-lensing result while the much higher source density from our WFC3 imaging data makes the current statistical uncertainty ~40% smaller.Comment: Accepted to Ap

Diffuse optical spectroscopic imaging reveals distinct early breast tumor hemodynamic responses to metronomic and maximum tolerated dose regimens.

BACKGROUND:Breast cancer patients with early-stage disease are increasingly administered neoadjuvant chemotherapy (NAC) to downstage their tumors prior to surgery. In this setting, approximately 31% of patients fail to respond to therapy. This demonstrates the need for techniques capable of providing personalized feedback about treatment response at the earliest stages of therapy to identify patients likely to benefit from changing treatment. Diffuse optical spectroscopic imaging (DOSI) has emerged as a promising functional imaging technique for NAC monitoring. DOSI uses non-ionizing near-infrared light to provide non-invasive measures of absolute concentrations of tissue chromophores such as oxyhemoglobin. In 2011, we reported a new DOSI prognostic marker, oxyhemoglobin flare: a transient increase in oxyhemoglobin capable of discriminating NAC responders within the first day of treatment. In this follow-up study, DOSI was used to confirm the presence of the flare as well as to investigate whether DOSI markers of NAC response are regimen dependent. METHODS:This dual-center study examined 54 breast tumors receiving NAC measured with DOSI before therapy and the first week following chemotherapy administration. Patients were treated with either a standard of care maximum tolerated dose (MTD) regimen or an investigational metronomic (MET) regimen. Changes in tumor chromophores were tracked throughout the first week and compared to pathologic response and treatment regimen at specific days utilizing generalized estimating equations (GEE). RESULTS:Within patients receiving MTD therapy, the oxyhemoglobin flare was confirmed as a prognostic DOSI marker for response appearing as soon as day 1 with post hoc GEE analysis demonstrating a difference of 48.77% between responders and non-responders (p < 0.0001). Flare was not observed in patients receiving MET therapy. Within all responding patients, the specific treatment was a significant predictor of day 1 changes in oxyhemoglobin, showing a difference of 39.45% (p = 0.0010) between patients receiving MTD and MET regimens. CONCLUSIONS:DOSI optical biomarkers are differentially sensitive to MTD and MET regimens at early timepoints suggesting the specific treatment regimen should be considered in future DOSI studies. Additionally, DOSI may help to identify regimen-specific responses in a more personalized manner, potentially providing critical feedback necessary to implement adaptive changes to the treatment strategy

First Report of NRG Oncology/Radiation Therapy Oncology Group 0622: A Phase 2 Trial of Samarium-153 Followed by Salvage Prostatic Fossa Irradiation in High-Risk Clinically Nonmetastatic Prostate Cancer After Radical Prostatectomy.

PURPOSE: To investigate the utility of 153Sm lexidronam (Quadramet) in the setting of men with prostate cancer status post radical prostatectomy who develop biochemical failure with no clinical evidence of osseous metastases. PATIENTS AND METHODS: Trial NRG Oncology RTOG 0622 is a single-arm phase 2 trial that enrolled men with pT2-T4, N0-1, M0 prostate cancer status post radical prostatectomy, who meet at least 1 of these biochemical failure criteria: (1) prostate-specific antigen (PSA) \u3e 1.0 ng/mL; (2) PSA \u3e 0.2 ng/mL if Gleason score 9 to 10; or (3) PSA \u3e 0.2 ng/mL if N1. Patients received 153Sm (2.0 mCi/kg intravenously × 1) followed by salvage external beam radiation therapy (EBRT) to the prostatic fossa (64.8-70.2 Gy in 1.8-Gy daily fractions). No androgen deprivation therapy was allowed. The primary objective was PSA response within 12 weeks of receiving 153Sm. The secondary objectives were to: (1) assess the completion rate for the regimen of 153Sm and EBRT; (2) evaluate the hematologic toxicity and other adverse events (AEs) at 12 and 24 weeks; and (3) determine the freedom from progression rate at 2 years. RESULTS: A total of 60 enrolled eligible patients were included in this analysis. Median follow-up was 3.97 years. A PSA response was achieved in 7 of 52 evaluable patients (13.5%), compared with the 25% hypothesized. The 2-year freedom from progression rate was 25.5% (95% confidence interval 14.4%-36.7%), and the biochemical failure rate was 64.4% (95% CI 50.5%-75.2%). Samarium-153 was well tolerated, with 16 (of 60) grade 3 to 4 hematologic AEs and no grade 5 hematologic AEs. Radiation therapy was also well tolerated, with no grade 3 to 5 acute radiation therapy-related AEs and 1 grade 3 to 4 and no grade 5 late radiation therapy-related AEs. CONCLUSIONS: Trial NRG Oncology RTOG 0622 did not meet its primary endpoint of PSA response, although the regimen of 153Sm and salvage EBRT was well tolerated. Although the toxicity profile supports study of 153Sm in high-risk disease, it may not be beneficial in men receiving EBRT

Universality of quantum Brownian motion

Are Markovian master equations for quantum Brownian motion independent of model assumptions used in the derivation and, thus, universal? With the aim of answering this question, we use a random band-matrix model for the system-bath interaction to derive Markovian master equations for the time evolution of one-dimensional quantum systems weakly coupled to a heat bath. We study in detail two simple systems, the harmonic oscillator and the two-level system. Our results are in complete agreement with those of earlier models, like the Caldeira-Legget model and, in the large-band limit, with the Agarwal equations (both with and without rotating-wave approximation). This proves the universality of these master equations.Comment: 24 page

Experimental comparison of autodyne and heterodyne laser interferometry using a Nd:YVO4 microchip laser

Using a Nd:YVO4 microchip laser with a relaxation frequency in the megahertz range, we have experimentally compared a heterodyne interferometer based on a Michelson configuration with an autodyne interferometer based on the laser optical feedback imaging (LOFI) method regarding their signal to noise ratios. In the heterodyne configuration, the beating between the reference beam and the signal beam is realized outside the laser cavity while in the autodyne configuration, the wave beating takes place inside the laser cavity and the relaxation oscillations of the laser intensity then play an important part. For a given laser output power, object under investigation and detection noise level, we have determined the amplification gain of the LOFI interferometer compared to the heterodyne interferometer. LOFI interferometry is demonstrated to show higher performances than heterodyne interferometry for a wide range of laser power and detection level of noise. The experimental results are in good agreement with the theoretical predictions

Hyperparathyroïdie Primaire durant la Gtrossesse: Etude d’Un cas Chru de Strasbourg

Introduction: L’hyperparathyroïdie primaire est une anomalie des glandes parathyroïdes avec hypersécrétion de parathormone (PTH), le plus souvent secondaire à un adénome parathyroïdien. Cas clinique: Il s’agit d’une patiente de 30 ans, troisième geste, primipare qui ne présente pas d’antécédents médicochirurgicaux particuliers sauf une césarienne à 41 semaines d’aménorrhée (SA) + 4 jours sous anesthésie générale pour altération du rythme cardiaque fœtal suite à un déclenchement par prostaglandines pour rupture prolongée des membranes. La grossesse en cours a été spontanée, marquée par plusieurs épisodes de coliques néphrétiques gauches sur lithiases urinaires dès le début. La patiente a été hospitalisée à 18 semaines d’aménorrhée pour hyperalgie lors d’un de ces épisodes avec discrète dilatation pyélocalicielle gauche à 10mm, sans infection urinaire associée. Le contrôle de la douleur a nécessité l’usage de morphiniques. Les résultats biologiques étaient en faveur d’une hyperparathyroïdie primaire diagnostiquée en fin de deuxième trimestre de grossesse. Ces résultats biologiques ont été confirmés par l’imagérie (échographie et scanner cervical). A la suite de ce bilan, une parathyroidectomie partielle a été réalisée à 31 semaines d’aménorrhée et deux jours. La calcémie était légèrement supérieure à la normale à 2.60 mmol/L avec une PTH à 105 ng/L le jour de l’intervention. La lésion a été analysée en anatomopathologie et confirmait la nature d’adénome mesurant 10x8x2 mm. La calcémie corrigée a nettement diminué suite à la chirurgie. La vitalité fœtale évaluée avec le score de Manning et les cardiotocographies étaient satisfaisantes avant et après l’intervention chirurgicale. Le suivi immédiat en post chirurgie était simple : une supplémentation calcique pour environ 15 jours a été utilisée suite à une hypocalcémie secondaire. La chirurgie a permis une amélioration nette de la symptomatologie de notre patiente de façon quasi immédiate. Une césarienne sous rachianesthésie pour désir maternel en début de travail a été réalisée à 39 semaines d’aménorrhées et 6 jours, dans le contexte d’utérus cicatriciel, donnant naissance à une petite fille de 3490g et 50 cm, APGAR 10-10-10-10 avec un pH artériel au cordon à 7,28. Aucune complication materno-fœtale n’a été rapportée dans le post-partum. Un suivi endocrinologique a été proposé au post-partum ainsi qu’un suivi urologique. Discussion: Sur le plan épidémiologique, l’hyperparathyroïdie est la troisième endocrinopathie la plus fréquente dans la population générale. Les patientes atteintes ont une symptomatologie très aspécifique. Le calcium est essentiel au bon fonctionnement de l’homéostasie chez l’homme et la femme, tant sur les plans neurologique, musculaire, hémostatique, que sur les plans de la multiplication et différenciation cellulaire. Il est donc nécessaire qu’un système puisse réguler de manière constante le phosphore et le calcium dans l’organisme car les complications maternofoetales surviennent en l’absence de diagnostic précoce. Plusieurs options thérapeutiques peuvent été envisagées et proposées à la patiente allant d’un simple suivi de contrôle régulier de la calcémie à la parathyroidectomie sélective en passant par un traitement médicamenteux. Notre cas clinique illustre un traitement chirurgical efficace au troisième trimestre de grossesse. Conclusion: La parathyroidectomie pendant le 3e trimestre de grossesse est une thérapeutique efficace pour le traitement de l’hyperparathyroïdie primaire symptomatique.   Introduction: Primary hyperparathyroidism is an abnormality of the parathyroid glands with parathyroid hormone hypersecretion (PTH), most often secondary to parathyroid adenoma. Clinical case: This is a 30-year-old patient, third procedure, primiparous who has no specific medical and surgical history except a cesarean section at 41 weeks of amenorrhea (AS) + 4 days under general anesthesia for impaired fetal heart rate. triggering by prostaglandins for prolonged rupture of membranes. The current pregnancy was spontaneous, marked by several episodes of renal colic on the left on urolithiasis from the start. The patient was hospitalized at 18 weeks amenorrhea for hyperalgesia during one of these episodes with discreet left pyelocalicular dilation to 10mm, without associated urinary tract infection. Pain control required the use of opioids. The laboratory results were in favor of primary hyperparathyroidism diagnosed at the end of the second trimester of pregnancy. These laboratory results were confirmed by imaging (ultrasound and cervical scan). Following this workup, a partial parathyroidectomy was performed at 31 weeks of amenorrhea and two days. Serum calcium was slightly above normal at 2.60 mmol / L with PTH of 105 ng / L on the day of surgery. The lesion was analyzed for anatomopathology and confirmed the nature of the adenoma measuring 10x8x2 mm. The corrected serum calcium significantly decreased following the surgery. Fetal vitality assessed with Manning's score and cardiotocographies were satisfactory before and after surgery. Immediate post-surgery follow-up was simple: calcium supplementation for around 15 days was used following secondary hypocalcaemia. The surgery allowed a marked improvement in the symptoms of our patient almost immediately. A cesarean section under spinal anesthesia for maternal desire at the start of labor was performed at 39 weeks of amenorrhea and 6 days, in the context of a scarred uterus, giving birth to a baby girl of 3490g and 50 cm, APGAR 10-10-10 -10 with an arterial cord pH of 7.28. No maternal-fetal complications have been reported in the postpartum period. Endocrinological follow-up has been proposed postpartum as well as urological follow-up. Discussion: Epidemiologically, hyperparathyroidism is the third most common endocrinopathy in the general population. The affected patients have very nonspecific symptoms. Calcium is essential for the proper functioning of homeostasis in men and women, both neurologically, muscularly, hemostatically, as well as in terms of cell multiplication and differentiation. It is therefore necessary that a system can constantly regulate phosphorus and calcium in the body because maternal-fetal complications occur in the absence of early diagnosis. Several treatment options can be considered and offered to the patient, ranging from simple regular monitoring of serum calcium to selective parathyroidectomy, including drug treatment. Our clinical case illustrates an effective surgical treatment in the third trimester of pregnancy. Conclusion: Parathyroidectomy in the 3rd trimester of pregnancy is an effective therapy for the treatment of symptomatic primary hyperparathyroidism

Selection for androgen receptor mutations in prostate cancers treated with androgen antagonist

The role of androgen receptor (AR) mutations in androgen-independent prostate cancer (PCa) was determined by examining AR transcripts and genes from a large series of bone marrow metastases. Mutations were found in 5 of 16 patients who received combined androgen blockade with the AR antagonist flutamide, and these mutant ARs were strongly stimulated by flutamide. In contrast, the single mutant AR found among 17 patients treated with androgen ablation monotherapy was not flutamide stimulated. Patients with flutamide-stimulated AR mutations responded to subsequent treatment with bicalutamide, an AR antagonist that blocks the mutant ARs. These findings demonstrate that AR mutations occur in response to strong selective pressure from flutamide treatment