The exclusive deep inelastic electroproduction of ψ(2S) and J/ψ(1S) at an ep centre-of-mass energy of 317 GeV has been studied with the ZEUS detector at HERA in the kinematic range 2<Q2<80 GeV2, ...30<W<210 GeV and |t|<1 GeV2, where Q2 is the photon virtuality, W is the photon–proton centre-of-mass energy and t is the squared four-momentum transfer at the proton vertex. The data for 2<Q2<5 GeV2 were taken in the HERA I running period and correspond to an integrated luminosity of 114 pb−1. The data for 5<Q2<80 GeV2 are from both HERA I and HERA II periods and correspond to an integrated luminosity of 468 pb−1. The decay modes analysed were μ+μ− and J/ψ(1S)π+π− for the ψ(2S) and μ+μ− for the J/ψ(1S). The cross-section ratio σψ(2S)/σJ/ψ(1S) has been measured as a function of Q2,W and t. The results are compared to predictions of QCD-inspired models of exclusive vector-meson production.
Aim
A total of 15–20% of patients with rectal cancer have liver metastases on presentation. The management of these patients is controversial. Heterogeneity in management strategies is considerable, ...with management often being dependent on local resources and available expertise.
Method
Members of the PelvEx Collaborative were invited to participate in the generation of a consensus statement on the optimal management of patients with advanced rectal cancer with liver involvement. Fifteen statements were created for topical discussion on diagnostic and management issues. Panellists were asked to vote on statements and anonymous feedback was given. A collaborative meeting was used to discuss any nuances and clarify any obscurity. Consensus was considered when > 85% agreement on a statement was achieved.
Results
A total of 135 participants were involved in the final round of the Delphi questionnaire. Nine of the 15 statements reached consensus regarding the management of patients with advanced rectal cancer and oligometastatic liver disease. Routine use of liver MRI was not recommended for patients with locally advanced rectal cancer, unless there was concern for metastatic disease on initial computed tomography staging scan. Induction chemotherapy was advocated as first‐line treatment in those with synchronous liver metastases in locally advanced rectal cancer. In the presence of symptomatic primary disease, a diverting stoma may be required to facilitate induction chemotherapy. Overall, only one‐quarter of the panellists would consider simultaneous pelvic exenteration and liver resection.
Conclusion
This Delphi process highlights the diverse treatment of advanced rectal cancer with liver metastases and provides recommendations from an experienced international group regarding the multidisciplinary management approach.
A
bstract
The production of beauty and charm quarks in
ep
interactions has been studied with the ZEUS detector at HERA for exchanged four-momentum squared 5
< Q
2
<
1000 GeV
2
using an integrated ...luminosity of 354 pb
−1
. The beauty and charm content in events with at least one jet have been extracted using the invariant mass of charged tracks associated with secondary vertices and the decay-length significance of these vertices. Differential cross sections as a function of
Q
2
, Bjorken
x
, jet trans- verse energy and pseudorapidity were measured and compared with next-to-leading-order QCD calculations. The beauty and charm contributions to the proton structure functions were extracted from the double-differential cross section as a function of
x
and
Q
2
. The running beauty-quark mass,
m
b
at the scale
m
b
, was determined from a QCD fit at next-to-leading order to HERA data for the first time and found to be
m
b
(
m
b
) = 4.07 ± 0.14 (fit)
− 0.07
+ 0.01
(mod.)
− 0.00
+ 0.05
(param.)
− 0.05
+ 0.08
(theo.) GeV.
A
bstract
Charm production in charged current deep inelastic scattering has been measured for the first time in
e
±
p
collisions, using data collected with the ZEUS detector at HERA, corresponding to ...an integrated luminosity of 358 pb
−1
. Results are presented separately for
e
+
p
and
e
−
p
scattering at a centre-of-mass energy of
s
= 318 GeV within a kinematic phase-space region of 200 GeV
2
<
Q
2
< 60000 GeV
2
and
y
< 0.9, where
Q
2
is the squared four-momentum transfer and
y
is the inelasticity. The measured cross sections of electroweak charm production are consistent with expectations from the Standard Model within the large statistical uncertainties.
Air pollution and pulmonary function Thaller, E.; Hollaway, L.; Mai, V. ...
Journal of allergy and clinical immunology,
02/2004, Letnik:
113, Številka:
2
Journal Article
Recenzirano
Recent studies have attempted to demonstrate a correlation between pollutants in the air and pulmonary function. Some studies have reported ozone and particulate matter to induce airway inflammation, ...but others suggest that known pollutants such as ozone do not affect spirometric measurements.
In the summers of 2002 and 2003, the Galveston Beach Patrol lifeguards were recruited to have their pulmonary functions recorded at three different times during the day. We obtained data on temperature, ozone, nitric oxide, nitrogen dioxide, and fine particulate matter from regulated sites in Galveston. The participants were required to complete daily surveys pertaining to their health, cigarette smoke exposure, and medication use.
In 2002, 45 participants between ages 16 and 27 completed the study. 13% reported a history of asthma, 39% reported smoke exposure, 44% reported having a recent respiratory illness, and less than 1% reported using asthma medications at any time during the study. We found a statistically significant reduction in FEV1 and FVC with increasing 2.5 micron particulate matter, but not with other pollution measurements. The FEV1/FVC ratio was not affected by particulate matter. Our 2003 data includes 54 subjects and shows similar results.
We conclude that elevated levels of 2.5 micron particulate matter adversely affects lung function in healthy individuals. Our data is consistent with previous studies. While our studies did not show that ozone affected pulmonary function, we experienced few days of high ozone.
Aim
We aim to compare machine learning with neural network performance in predicting R0 resection (R0), length of stay > 14 days (LOS), major complication rates at 30 days postoperatively (COMP) and ...survival greater than 1 year (SURV) for patients having pelvic exenteration for locally advanced and recurrent rectal cancer.
Method
A deep learning computer was built and the programming environment was established. The PelvEx Collaborative database was used which contains anonymized data on patients who underwent pelvic exenteration for locally advanced or locally recurrent colorectal cancer between 2004 and 2014. Logistic regression, a support vector machine and an artificial neural network (ANN) were trained. Twenty per cent of the data were used as a test set for calculating prediction accuracy for R0, LOS, COMP and SURV. Model performance was measured by plotting receiver operating characteristic (ROC) curves and calculating the area under the ROC curve (AUROC).
Results
Machine learning models and ANNs were trained on 1147 cases. The AUROC for all outcome predictions ranged from 0.608 to 0.793 indicating modest to moderate predictive ability. The models performed best at predicting LOS > 14 days with an AUROC of 0.793 using preoperative and operative data. Visualized logistic regression model weights indicate a varying impact of variables on the outcome in question.
Conclusion
This paper highlights the potential for predictive modelling of large international databases. Current data allow moderate predictive ability of both complex ANNs and more classic methods.
Associated with changes in the level of physiological activity in neuronal tissue are changes in the intrinsic optical properties of the tissue. As a consequence, it is possible to optically monitor ...neuronal activity without the use of dyes or other contrast-enhancing agents. Such optical techniques have been applied in the laboratory for more than 50 years. Recent developments in near-infrared spectroscopy and intraoperative optical imaging have suggested a number of clinically important applications of this technology. This article provides an overview of what is known about the physiological correlates and underlying mechanisms associated with activity-evoked optical changes in neuronal tissue.
Meckel's diverticulum is an embryologic remnant of the vitelline duct, occurring in approximately 2% of the adult population. A hernia containing a Meckel's diverticulum is called a Littré's hernia ...and is rarely reported in the medical literature. Clinically, a Littré's hernia is indistinguishable from a hernia containing small bowel and is often discovered incidentally during a repair.
Herein, we report a rare case of strangulated Littré's hernia in a patient's right groin. The sac contained a long segment of small bowel in addition to a large Meckel's diverticulum. The bowel was irreducible through the groin incision, and a lower midline laparotomy was made. Necrotic bowel including the Meckel's diverticulum was resected. Given the presence of necrotic bowel and potential for infection, the hernia was repaired with a Bassini herniorrhaphy, reinforced with absorbable mesh. The patient recovered uneventfully.
Littré's hernia is a rare clinical entity. Treatment is similar to any bowel-containing hernia. Repair of the hernia defect with permanent mesh should be weighed against the risk of implant infection.
The dissociation of virtual photons,
γ
⋆
p
→
X
p
, in events with a large rapidity gap between
X and the outgoing proton, as well as in events in which the leading proton was directly measured, has ...been studied with the ZEUS detector at HERA. The data cover photon virtualities
Q
2
>
2
GeV
2
and
γ
⋆
p
centre-of-mass energies
40
<
W
<
240
GeV
, with
M
X
>
2
GeV
, where
M
X
is the mass of the hadronic final state,
X. Leading protons were detected in the ZEUS leading proton spectrometer. The cross section is presented as a function of
t, the squared four-momentum transfer at the proton vertex and
Φ, the azimuthal angle between the positron scattering plane and the proton scattering plane. It is also shown as a function of
Q
2
and
x
P
, the fraction of the proton's momentum carried by the diffractive exchange, as well as
β, the Bjorken variable defined with respect to the diffractive exchange.
Daryl W. Hochman 1 ,
Raimondo D'Ambrosio 1 ,
Damir Janigro 1 , and
Philip A. Schwartzkroin 1 , 2
1 Department of Neurological Surgery; and 2 Department of Physiology and Biophysics, University of ...Washington, Seattle, Washington 98195
Hochman, Daryl W., Raimondo D'Ambrosio, Damir Janigro, and Philip A. Schwartzkroin. Extracellular chloride and the maintenance of spontaneous epileptiform activity in rat hippocampal slices. J. Neurophysiol. 81: 49-59, 1999. Previous studies showed that furosemide blocks spontaneous epileptiform activity without diminishing synaptic transmission or reducing hyperexcited field responses to electrical stimuli. We now test the hypothesis that the antiepileptic effects of furosemide are mediated through its blockade of the Na + ,K + ,2Cl cotransporter and thus should be mimicked by a reduction of extracellular chloride (Cl o ). In the first set of experiments, field recordings from the CA1 cell body layer of hippocampal slices showed that spontaneous bursting developed within 10-20 min in slices perfused with low-Cl o (7 mM) medium but that this spontaneous epileptiform activity ceased after a further 10-20 min. Intracellular recordings from CA1 pyramidal cells showed that normal action potential discharge could be elicited by membrane depolarization, even after the tissue was perfused with low-Cl o medium for >2 h. In a second set of experiments, spontaneous bursting activity was induced in slices by perfusion with high-K + o (10 mM), bicuculline (100 µM), or 4-aminopyridine (100 µM). In each case, recordings from the CA1 region showed that reduction of Cl o to 21 mM reversibly blocked the bursting within 1 h. Similar to previous observations with furosemide treatment, low-Cl o medium blocked spontaneous hypersynchronous discharges without reducing synaptic hyperexcitability (i.e., hyperexcitable field responses evoked by electrical stimulation). In a third set of experiments, prolonged exposure (>1 h after spontaneous bursting ceased) of slices to systematically varied Cl o and K + o resulted in one of three types of events: 1 ) spontaneous, long-lasting, and repetitive negative field potential shifts (7 mM Cl o ; 3 mM K + o ); 2 ) oscillations consisting of 5- to 10-mV negative shifts in the field potential, with a period of ~1 cycle/40 s (16 mM Cl o ; 12 mM K + o ); and 3 ) shorter, infrequently occurring negative field shifts lasting 20-40 s (21 mM Cl o ; 3 mM K + o ). Our observations indicate that the effects of low Cl o on neuronal synchronization and spontaneous discharge are time dependent. Similar effects were seen with furosemide and low Cl o , consistent with the hypothesis that the antiepileptic effect of furosemide is mediated by the drug's effect on chloride transporters. Finally, the results of altering extracellular potassium along with chloride suggest that blockade of the Na + , K + ,2Cl cotransporter, which normally transports chloride from the extracellular space into glial cells, is key to these antiepileptic effects.
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