Spontaneous Symmetry Breaking and the Renormalization of the Chern-Simons Term

We calculate the one-loop perturbative correction to the coefficient of the \cs term in non-abelian gauge theory in the presence of Higgs fields, with a variety of symmetry-breaking structures. In the case of a residual $U(1)$ symmetry, radiative corrections do not change the coefficient of the \cs term. In the case of an unbroken non-abelian subgroup, the coefficient of the relevant \cs term (suitably normalized) attains an integral correction, as required for consistency of the quantum theory. Interestingly, this coefficient arises purely from the unbroken non-abelian sector in question; the orthogonal sector makes no contribution. This implies that the coefficient of the \cs term is a discontinuous function over the phase diagram of the theory.Comment: Version to be published in Phys Lett B., minor additional change

Diffusive Charge Transport in Graphene on SiO2

We review our recent work on the physical mechanisms limiting the mobility of graphene on SiO2. We have used intentional addition of charged scattering impurities and systematic variation of the dielectric environment to differentiate the effects of charged impurities and short-range scatterers. The results show that charged impurities indeed lead to a conductivity linear in density in graphene, with a scattering magnitude that agrees quantitatively with theoretical estimates [1]; increased dielectric screening reduces scattering from charged impurities, but increases scattering from short-range scatterers [2]. We evaluate the effects of the corrugations (ripples) of graphene on SiO2 on transport by measuring the height-height correlation function. The results show that the corrugations cannot mimic long-range (charged impurity) scattering effects, and have too small an amplitude-to-wavelength ratio to significantly affect the observed mobility via short-range scattering [3, 4]. Temperature-dependent measurements show that longitudinal acoustic phonons in graphene produce a resistivity linear in temperature and independent of carrier density [5]; at higher temperatures, polar optical phonons of the SiO2 substrate give rise to an activated, carrier density-dependent resistivity [5]. Together the results paint a complete picture of charge carrier transport in graphene on SiO2 in the diffusive regime.Comment: 28 pages, 7 figures, submitted to Graphene Week proceeding

Accuracy of FDG PET-CT response assessment following radiotherapy alone for head and neck squamous cell carcinoma: retrospective analysis of 45 patients.

FDG PET-CT is an established tool for response assessment following definitive concurrent chemoradiotherapy for head and neck squamous cell carcinoma with a high negative predictive value guiding treatment decisions. Little data is available regarding the accuracy of FDG PET-CT for response assessment following definitive radiotherapy without chemotherapy. We retrospectively analysed the accuracy of FDG PET-CT for response assessment following radiotherapy alone without planned neck dissection in 45 patients. PET-CT had a high negative predictive value of 93% and positive predictive value of 88%. Based upon the high negative predictive value, PET-CT can be used to avoid surgical intervention following radiotherapy alone

Prognostic and mechanistic potential of progesterone sulfates in intrahepatic cholestasis of pregnancy and pruritus gravidarum

A challenge in obstetrics is to distinguish pathological symptoms from those associated with normal changes of pregnancy, typified by the need to differentiate whether gestational pruritus of the skin is an early symptom of intrahepatic cholestasis of pregnancy (ICP) or due to benign pruritus gravidarum. ICP is characterized by raised serum bile acids and complicated by spontaneous preterm labor and stillbirth. A biomarker for ICP would be invaluable for early diagnosis and treatment and to enable its differentiation from other maternal diseases. Three progesterone sulfate compounds, whose concentrations have not previously been studied, were newly synthesized and assayed in the serum of three groups of ICP patients and found to be significantly higher in ICP at 9-15 weeks of gestation and prior to symptom onset (group 1 cases/samples: ICP n = 35/80, uncomplicated pregnancy = 29/100), demonstrating that all three progesterone sulfates are prognostic for ICP. Concentrations of progesterone sulfates were associated with itch severity and, in combination with autotaxin, distinguished pregnant women with itch that would subsequently develop ICP from pruritus gravidarum (group 2: ICP n = 41, pruritus gravidarum n = 14). In a third group of first-trimester samples all progesterone sulfates were significantly elevated in serum from low-risk asymptomatic women who subsequently developed ICP (ICP/uncomplicated pregnancy n = 54/51). Finally, we show mechanistically that progesterone sulfates mediate itch by evoking a Tgr5-dependent scratch response in mice. Conclusion: Our discovery that sulfated progesterone metabolites are a prognostic indicator for ICP will help predict onset of ICP and distinguish it from benign pruritus gravidarum, enabling targeted obstetric care to a high-risk population. Delineation of a progesterone sulfate-TGR5 pruritus axis identifies a therapeutic target for itch management in IC

Peritonitis secondary to traumatic duodenal laceration in the presence of a large pancreatic pseudocyst: a case report

<p>Abstract</p> <p>Introduction</p> <p>A pancreatic pseudocyst is a common sequela of severe acute pancreatitis. Commonly, it presents with abdominal pain and a mass in the epigastrium several weeks after the acute episode and can be managed conservatively, endoscopically or surgically. We report a patient with a pancreatic pseudocyst awaiting endoscopic therapy who developed a life-threatening complication following a rather innocuous trauma to the abdomen.</p> <p>Case presentation</p> <p>A 23-year-old Asian male student presented as an emergency with an acute abdomen a week after a minor trauma to his upper abdomen. The injury occurred when he was innocently punched in the abdomen by a friend. He experienced only moderate discomfort briefly at the time. His past medical history included coeliac disease and an admission four months previously with severe acute pancreatitis. He was hospitalized for 15 days; his pancreatitis was thought to be due to alcohol binge drinking on weekends. Ultrasound scanning showed no evidence of gallstone disease. Five days after the trauma, he became anorexic, lethargic and feverish and started vomiting bilious content. Seven days post-trauma, he presented to our emergency department with severe abdominal pain. An emergency laparotomy was performed where a transverse linear duodenal laceration was found at the junction of the first and second part of his duodenum, with generalized peritonitis. His stomach and duodenum were stretched over a large pancreatic pseudocyst posterior to his stomach. It was postulated that an incomplete duodenal injury (possibly a serosal tear) occurred following the initial minor trauma, which was followed by local tissue necrosis at the injury site resulting in a delayed presentation of generalized peritonitis.</p> <p>Conclusion</p> <p>This is the first reported case of a traumatic duodenal laceration following minor blunt trauma in the presence of a large pancreatic pseudocyst. Minor blunt abdominal trauma in a normal healthy adult would not be expected to result in a significant duodenal injury. In the presence of a large pseudocyst, however, the stretching of the duodenum over the pseudocyst had probably predisposed the duodenum to this injury. Patients awaiting therapeutic interventions for their pancreatic pseudocysts should be warned about this unusual but life-threatening risk following minor blunt abdominal trauma.</p

Antigen-Presenting Activity of Non-Langerhans Epidermal Cells in Contact Hypersensitivity Reactions

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72263/1/j.1365-3083.1990.tb02914.x.pd

Variation in hospital treatment patterns for metastatic colorectal cancer

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/111784/1/cncr29253.pd

Kinetic modeling of NH3-SCR over a supported Cu zeolite catalyst using axial species distribution measurements

In this study, a kinetic model is developed for NH3-SCR over a honeycomb-monolith-supported Cu-zeolites using intra-catalyst axial species distribution measurements. An ammonia TPD experiment, together with micro calorimetry data were used for tuning the ammonia adsorption and desorption properties. The spatial distribution for NO oxidation, NH3 oxidation and NH3 "Standard" SCR were modeled between 200 and 400 degrees C. Four-step protocol measurements were employed in order to validate the transient functions of the model. The resulting kinetic model provides good spatiotemporal simulation of the SCR reaction and component reactions throughout the monolith catalyst system