9 research outputs found
Energy Response and Longitudinal Shower Profiles Measured in CMS HCAL and Comparison With Geant4
The response of the CMS combined electromagnetic and hadron calorimeter to beams of pions with momenta in the range 5-300 GeV/c has been measured in the H2 test beam at CERN. The raw response with the electromagnetic compartment calibrated to electrons and the hadron compartment calibrated to 300 GeV pions may be represented by sigma = (1.2) sqrt{E} oplus (0.095) E. The fraction of energy visible in the calorimeter ranges from 0.72 at 5 GeV to 0.95 at 300 GeV, indicating a substantial nonlinearity. The intrinsic electron to hadron ratios are fit as a function of energy and found to be in the range 1.3-2.7 for the electromagnetic compartment and 1.4-1.8 for the hadronic compartment. The fits are used to correct the non-linearity of the e pi response to 5% over the entire measured range resulting in a substantially improved resolution at low energy. Longitudinal shower profile have been measured in detail and compared to Geant4 models, LHEP-3.7 and QGSP-2.8. At energies below 30 GeV, the data, LHEP and QGSP are in agreement. Above 30 GeV, LHEP gives a more accurate simulation of the longitudinal shower profile
Design, Performance and Calibration of the CMS Forward Calorimeter Wedges
We report on the test beam results and calibration methods using charged particles of the CMS Forward Calorimeter (HF). The HF calorimeter covers a large pseudorapidity region (3\l |\eta| \le 5), and is essential for large number of physics channels with missing transverse energy. It is also expected to play a prominent role in the measurement of forward tagging jets in weak boson fusion channels. The HF calorimeter is based on steel absorber with embedded fused-silica-core optical fibers where Cherenkov radiation forms the basis of signal generation. Thus, the detector is essentially sensitive only to the electromagnetic shower core and is highly non-compensating (e/h \approx 5). This feature is also manifest in narrow and relatively short showers compared to similar calorimeters based on ionization. The choice of fused-silica optical fibers as active material is dictated by its exceptional radiation hardness. The electromagnetic energy resolution is dominated by photoelectron statistics and can be expressed in the customary form as a/\sqrt{E} + b. The stochastic term a is 198% and the constant term b is 9%. The hadronic energy resolution is largely determined by the fluctuations in the neutral pion production in showers, and when it is expressed as in the electromagnetic case, a = 280% and b = 11%
The utility of cardiac MRI in diagnosis of infective endocarditis: preliminary results
PURPOS
Increase in pro-apoptotic Bax expression and decrease in anti-apoptotic Bcl-2 expression in newborns with necrotizing enterocolitis.
The aim of the present study was to find out if there is an increase in the expression of pro-apoptotic Bax and reduction in expression of anti-apoptotic Blc-2A1 in newborn intestines with necrotizing enterocolitis (NEC)
Effects of Local and Sustained Release of FGF, IGF, and GH on Germ Cells in Unilateral Undescended Testis in Rats
OBJECTIVES To evaluate the effects of the local release of fibroblast growth factor (FGF), insulin-like growth factor (IGF), and growth hormone (GH) on a germ cell population of ipsilateral undescended and contralateral descended testes of rats with a surgically created unilateral abdominal testis for 12 weeks and after the application of growth factors after orchidopexy
Assessment of Developmental And Radiological Long-Term Outcome of Children with Surgically Treated Midgut Volvulus
Background/aim: The aim is to evaluate the long-term outcome of asymptomatic patients who underwent surgical correction for midgut volvulus. Materials and methods: Seven patients managed surgically for midgut volvulus in the last 3 years were included. Demographic features, symptoms at presentation, diagnoses, surgical procedures, and complications were recorded. Patients were then contacted for follow-up and evaluation of long-term outcomes. General physical conditions, anthropometric parameters, feeding habits, and defecation histories were evaluated. Laboratory examinations were performed. Color Doppler ultrasonography (CDUS) was performed to evaluate blood flow in the superior mesenteric artery (SMA). Results: In total, seven patients were identified. The median age at admission was 3 days (0-90 days). Mean age at follow-up was 17 +/- 2 months. Growth parameters were normal in all cases. Four patients had low levels of ferritin and transferrin saturation. One patient had microcytic anemia. Another patient had low serum zinc level. One patient who had ileal resection had a high level of steatorrhea in stool examination. In CDUS, SMA blood flow volume was low in all cases. Peak-systolic velocity and resistance index were low in all but one case. Conclusion: Despite uneventful postoperative courses, all patients operated on for midgut volvulus showed mild laboratory changes and decreased blood flow in the SMA in long-term follow-up.WoSScopu
Increase in pro-apoptotic Bax expression and decrease in anti-apoptotic Bcl-2 expression in newborns with necrotizing enterocolitis
Background/Aim. The aim of the present study was to find out if there is
an increase in the expression of pro-apoptotic Bax and reduction in
expression of anti-apoptotic Blc-2A1 in newborn intestines with
necrotizing enterocolitis (NEC).
Material and Methods. We compared 8 consecutive newborn patients
undergoing bowel resection for NEC with 8 neonates undergoing intestinal
resection for ileal atresia.
Histopathological evaluation of tissue injury and apoptosis was
performed by using light microscopic examination and TUNEL method. The
mRNA level of apoptotic (CASP3, CASP6, CASP7, Bax, BIRC2) and
anti-apoptotic genes were evaluated by PCR array method. Protein
expression was assessed by immunohistochemistry.
Results. Tissue injury scores and mean apoptosis scores were
significantly higher in NEC group when compared with control group (p <
0.01). Expression of pro-apoptotic genes were significantly increased in
NEC group when compared with control group (p < 0.01). Expression of
anti-apoptotic Bcl-2A1 gene was significantly decreased in NEC group, (p
< 0.01). Protein expression of Bax and CASP3 was significantly increased
in NEC group, (p < 0.01).
Conclusion. Our data in human newborns suggest that alteration of the
balance between pro-apoptotic Bax expression and antiapoptotic Bcl-2A1
expression in the site of injury is a possible mechanism in the
pathogenesis of NEC