Enhancement of superconductivity near a nematic quantum critical point

We consider a low T_{c} metallic superconductor weakly coupled to the soft fluctuations associated with proximity to a nematic quantum critical point (NQCP). We show that (1) a BCS-Eliashberg treatment remains valid outside of a parametrically narrow interval about the NQCP, (2) the symmetry of the superconducting state (d wave, s wave, p wave) is typically determined by the noncritical interactions, but T_{c} is enhanced by the nematic fluctuations in all channels, and (3) in 2D, this enhancement grows upon approach to criticality up to the point at which the weak coupling approach breaks down, but in 3D, the enhancement is much weaker.

[Practical Implementation of the "Four-column Concept" in the Situation-Adjusted Therapy for Haemorrhoidal Disease in the Daily Routine of a Proctology Department]

INTRODUCTION

In addition to the stage, several factors influence the treatment of haemorrhoids. The aim of this study was the elaboration of an individual therapy concept which is situation-adjusted. In this context, our own experience and approaches are presented.

MATERIALS AND METHODS

In the Department of Coloproctology of the Prosper-Hospital Recklinghausen, from January 2009 to August 2012, 903 haemorrhoidectomies (2nd to 4th degree) have been performed. We report our results on the practical implementation of a situation-adjusted treatment of haemorrhoidal disease. In this context we present an overview of effective modifications of surgical techniques. Retrospectively the perioperative course and postoperative outcome were evaluated.

RESULTS

Even in a collective with a large number of high-risk patients (26 %) respecting the "four columns" that constitute the fundament of a situation-adjusted treatment of haemorrhoids, high patient satisfaction and good outcome with low complication (7 %) and recurrence (0 %) rates could be attained.

CONCLUSION

The "four columns" (findings of examination, therapeutic options, physician and patient) form the fundament of an effective treatment of haemorrhoidal disease without many complications and guarantee an individually tailored therapy for each patient.

[Situation-adjusted Treatment of Haemorrhoidal Disease]

In addition to the stage several factors influence the treatment of haemorrhoids. The adequate treatment of haemorrhoids is not solely dependent on the stage, thus a situation-adapted therapy should be preferred. Advantages, disadvantages and specific characteristics of different therapy strategies in addition to potential complication risks have to be evaluated in order to obtain an effective and low-risk course. Also requests and personal living conditions of the patient as well as the expertise and experience of the physician have to be considered. A review of the current literature has been performed and a "four columns concept" has been developed that constitutes the fundament of a situation-adjusted treatment of haemorrhoids. The "four columns" that should be considered when therapy strategies are determined are composed of the following key factors: diagnostic findings, treatment alternatives, physician, and patient.

[Anal sphincter repair in the treatment of anal incontinence - when and how to do it?]

Anal incontinence is a disease of high prevalence. For many patients the disease causes severe stress and often results in social isolation. Whenever a sphincter lesion has been diagnosed by digital rectal examination and endosonographic access, anal sphincter reconstruction can be performed with the same results either in overlapping or in end-to-end suture technique. sing these procedures, in more than 60 % of patients the continence can be initially improved. However, benefit decreases after 5 years down to 40-50 %. The prognosis gets worse with increasing age and supplementary descending pelvic floor. Anal repair with reconstruction of internal and external sphincters is performed in neurogenic incontinence. This can be achieved by posterior or anterior anal repair (total pelvic floor repair). Nowadays these procedures are not common, due to unsuccessfulness. Instead, sacral nerve stimulation as a more expensive but less invasive method has displaced the anal repair on this indication. Interpretation of the published results remains delicate because of heterogenous evaluation criteria of postoperative outcome: subjective amelioration, postoperative satisfaction and quality of life, improvement of incontinence score or achievement of complete anal continence. However, it is proven that after immediate reconstruction of traumatic sphincter lesions the postoperative outcome is better than a two-step operation with primary ostomy.

Sci-Fri AM: Imaging - 08: Comparison of single and dual layer detector blocks for pre-clinical MRI-PET

Our group is developing a small animal PET scanner which would fit in a 7 Tesla MRI scanner to provide simultaneous PET and MR acquisitions and images. There is very little room for the PET detectors and we must use nonmagnetic materials. This presentation describes preliminary work with two PET detectors consisting of LYSO blocks each with two crystal layers: 49 1.67*1.67*6.0 mm on the bottom layer and 36 4.0 mm deep crystals on the top layer. These are mounted on SensL 4*4 arrays of silicon photo-multipliers whose outputs are multiplexed to provide three signals: Energy, X, Y. These detectors were mounted on translation stages and scanned past a 0.25 mm diameter 370 MBq Na-18 source embedded in tissue equivalent plastic. The results were compared with similar single layer crystal blocks with 10 mm deep crystals to assess the advantage of dual layer crystals to reduce radial blurring in a PET scanner with a diameter of only 64 mm. The ability to identify correctly each crystal is reported as its resolvability index, (RI), defined as the (crystal response FWHM)/(crystal's separation) in the crystal identification matrix. For the dual layer block RI =0.44, and for dual layer block RI=0.22. The coincidence response resolution for the single layer block varied from 1.23±0.05 mm at the centre of the scanner to 3.09±0.10 mm at 15.8 mm radius, while the dual layer block varied from 1.31±0.06 to 1.96±0.51 mm over the same range, confirming the Monte-Carlo simulations showing reduced radial blurring.

Proteases in Plasma and Kidney of db/db Mice as Markers of Diabetes-Induced Nephropathy

Db/db mice are overweight, dyslipidemic and develop diabetic complications, relevant for similar complications in human type 2 diabetes. We have used db/db and db/+ control mice to investigate alterations in proteinase expression and activity in circulation and kidneys by SDS-PAGE zymography, electron microscopy, immunohistochemistry, Western blotting, and in situ zymography. Plasma from db/db mice contained larger amounts of serine proteinases compared to db/+ mice. Kidneys from the db/db mice had a significantly larger glomerular surface area and somewhat thicker glomerular basement membranes compared to the db/+ mice. Furthermore, kidney extracts from db/+ mice contained metalloproteinases with M_r of approximately 92000, compatible with MMP-9, not observed in db/db mice. These results indicate that higher levels of serine proteinases in plasma may serve as potential markers for kidney changes in db/db mice, whereas a decrease in MMP-9 in the kidney may be related to the glomerular changes.

[Pathological work-up of rectal cancer following partial/total mesorectal excision]

Total mesorectal excision (TME) refers to the anatomically accurate surgical resection of the rectum from its surrounding fascias and has become the gold standard for treating rectal cancer. The pathologist plays a key role in the assessment of these specimens and good pathological reporting of rectal cancer is essential to achieving the optimum possible results for patients with rectal cancer. In experienced hands, these techniques result in a dramatic improvement in cancer-related cure rates from 45% to 75% and a reduction in pelvic recurrences from 40% to 5%-10%. Moreover, preservation of sexual and urinary functions is possible in the majority of cases. This article reviews the pathological assessment of the TME specimen in detail with regards to current international guidelines and describes its anatomical background. In addition, particular issues relating to margins, lymph node dissection and effects of neoadjuvant therapy are discussed.

Metastable π junction between an s(±)-wave and an s-wave superconductor

We examine a contact between a superconductor whose order parameter changes sign across the Brillioun zone, and an ordinary, uniform-sign superconductor. Within a Ginzburg-Landau-type model, we find that if the barrier between the two superconductors is not too high, the frustration of the Josephson coupling between different portions of the Fermi surface across the contact can lead to surprising consequences. These include time-reversal symmetry breaking at the interface and unusual energy-phase relations with multiple local minima. We propose this mechanism as a possible explanation for the half-integer flux quantum transitions in composite niobium-iron pnictide superconducting loops, which were discovered in recent experiments [C.-T. Chen et al., Nature Phys. 6, 260 (2010).].

Second brain death examination may negatively affect organ donation

BACKGROUND

Little is known about the impact of the requirement for a second brain death examination on organ donation. In New York State, 2 examinations 6 hours apart have been recommended by a Department of Health panel.

METHODS

We reviewed data for 1,229 adult and 82 pediatric patients pronounced brain dead in 100 New York hospitals serviced by the New York Organ Donor Network from June 1, 2007, to December 31, 2009. We reviewed the time interval between the 2 clinical brain death examinations and correlated this brain death declaration interval to day of the week, hospital size, and organ donation.

RESULTS

None of the patients declared brain dead were found to regain brainstem function upon repeat examination. The mean brain death declaration interval between the 2 examinations was 19.2 hours. A 26% reduction in brain death examination frequency was seen on weekends when compared to weekdays (p = 0.0018). The mean brain death interval was 19.9 hours for 0-750 bed hospitals compared to 16.0 hours for hospitals with more than 750 beds (p = 0.0015). Consent for organ donation decreased from 57% to 45% as the brain death declaration interval increased. Conversely, refusal of organ donation increased from 23% to 36% as the brain death interval increased. A total of 166 patients (12%) sustained a cardiac arrest between the 2 examinations or after the second examination.

CONCLUSION

A single brain death examination to determine brain death for patients older than 1 year should suffice. In practice, observation time to a second neurologic examination was 3 times longer than the proposed guideline and associated with substantial intensive care unit costs and loss of viable organs.

Fractional charges on an integer quantum Hall edge

We propose ways to create and detect fractionally charged excitations in integer quantum Hall edge states. The charge fractionalization occurs due to the Coulomb interaction between electrons propagating on different edge channels. The fractional charge of the solitonlike collective excitations can be observed in time-resolved or frequency-dependent shot noise measurements.

Position paper: recommendation on the adoption of breathing patterns for infants and small children in general chapter 2.9.44. Preparations for nebulisation

The treatment of infants and small children with nebuliser-based therapy is commonplace. However, the breathing pattern proposed for general chapter 2.9.44 covering preparations for nebulisation, in development for the European Pharmacopoeia, is that of an adult at rest. This position paper is a concise summary of recommendations for 3 breathing patterns that would be applicable to a neonate, a 12-month-old infant, and a child approximately 4 years old. The information presented herein is intended to inform the development of the proposed general chapter with the intention that information be provided to assist those involved with the evaluation of preparations for paediatric use in the choice of more appropriate breathing patterns for the assessment of active substance delivery rate and total active substance delivered.

Cooling the NGI - an approach to size a nebulised aerosol more accurately

The European Pharmaceutical Aerosol Group (EPAG) has undertaken investigations with the aim of developing robust methods for the droplet size analysis of nebuliser-produced aerosols in support of the proposed European Pharmacopeia general chapter 2.9.44 covering preparations for nebulisation. A multi-centre study was designed to investigate the effects of cooling the Next Generation pharmaceutical Impactor (NGI) before sample collection, as a means of reducing bias and variability caused by heat transfer-related evaporation. Droplets containing salbutamol were sized from 3 different nebulisers chosen to offer fundamentally different modes of aerosol generation: AeroNeb Go, a vibrating mesh nebuliser; PARI LC Plus, a breath-enhanced jet nebuliser; and MistyMax, a constant-output jet nebuliser. Each laboratory undertook determinations at ambient temperature, using an NGI pre-cooled in a refrigerator (5 degrees C for at least 90 min). The corresponding measurements were made using an ambient NGI as a benchmark. Salbutamol solution 5 mg/2 ml (Teva, Runcorn, UK) was used throughout the study. Analysis of individual and pooled results from 5 of the participants showed a similar trend insofar as the cooled NGI yielded a coarser nebulised aerosol than that obtained by the ambient NGI. Mass Median Aerodynamic Diameter (MMAD) was on average reduced by 9.5-21.9 % and the Fine Droplet Fraction < 5 microm (FDF) increased on average by 5.5-17.4 % for all the nebuliser designs when comparing ambient to cooled NGI. Despite the more laborious procedure of cooling the NGI, variability in data was generally similar to that obtained with the ambient NGI. We conclude that it is beneficial to cool the NGI when sizing nebulised aerosol. Furthermore, occasional findings during this study revealed a build-up of solute deposits within the interior of the NGI, and a more rigorous impactor cleaning/drying procedure is therefore recommended.

Assessment of the need to coat particle collection cups of the NGI to mitigate droplet bounce when evaluating nebuliser-produced droplets

The European Pharmaceutical Aerosol Group (EPAG) has been undertaking a series of investigations in support of developing robust methods for the droplet size analysis of nebuliser-produced aerosols for the proposed European Pharmacopoeia general chapter 2.9.44 covering preparations for nebulisation. The present two-centre study, which was designed to confirm whether or not coating the collection cups of the Next Generation pharmaceutical Impactor (NGI, the recommended impactor for the proposed monograph) is required, forms part of these investigations. The study evaluated NGI-measured aerodynamic droplet-size distributions of aerosols of a generic salbutamol solution for nebulisation generated by two different jet nebulisers. The results demonstrated that there was no indication of biased stage deposition when silicone oil was used to coat the impaction surfaces, as compared to uncoated surfaces. The conclusion was that there is no need to coat the NGI cups when nebulised products are investigated.