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1.
AJNR Am J Neuroradiol ; 44(6): 700-706, 2023 06.
Article in English | MEDLINE | ID: mdl-37142433

ABSTRACT

BACKGROUND AND PURPOSE: Children with spastic cerebral palsy have motor deficits associated with periventricular leukomalacia indicating WM damage to the corticospinal tracts. We investigated whether practice of skilled lower extremity selective motor control movements would elicit neuroplasticity. MATERIALS AND METHODS: Twelve children with spastic bilateral cerebral palsy and periventricular leukomalacia born preterm (mean age, 11.5 years; age range, 7.3-16.6 years) participated in a lower extremity selective motor control intervention, Camp Leg Power. Activities promoted isolated joint movement including isokinetic knee exercises, ankle-controlled gaming, gait training, and sensorimotor activities (3 hours/day, 15 sessions, 1 month). DWI scans were collected pre- and postintervention. Tract-Based Spatial Statistics was used to analyze changes in fractional anisotropy, radial diffusivity, axial diffusivity, and mean diffusivity. RESULTS: Significantly reduced radial diffusivity (P < . 05) was found within corticospinal tract ROIs, including 28.4% of the left and 3.6% of the right posterior limb of the internal capsule and 14.1% of the left superior corona radiata. Reduced mean diffusivity was found within the same ROIs (13.3%, 11.6%, and 6.6%, respectively). Additionally, decreased radial diffusivity was observed in the left primary motor cortex. Additional WM tracts had decreased radial diffusivity and mean diffusivity, including the anterior limb of the internal capsule, external capsule, anterior corona radiata, and corpus callosum body and genu. CONCLUSIONS: Myelination of the corticospinal tracts improved following Camp Leg Power. Neighboring WM changes suggest recruitment of additional tracts involved in regulating neuroplasticity of the motor regions. Intensive practice of skilled lower extremity selective motor control movements promotes neuroplasticity in children with spastic bilateral cerebral palsy.


Subject(s)
Cerebral Palsy , Leukomalacia, Periventricular , White Matter , Infant, Newborn , Humans , Child , Adolescent , Cerebral Palsy/complications , Cerebral Palsy/diagnostic imaging , Diffusion Tensor Imaging , Leg , Muscle Spasticity , Lower Extremity , Anisotropy
2.
J Chem Phys ; 156(5): 054301, 2022 Feb 07.
Article in English | MEDLINE | ID: mdl-35135286

ABSTRACT

The ion-induced fragmentation of CH4 2+ into H+ and CH3 + is studied using a cold target recoil ion momentum spectroscopy in coincidence with the charge state of the post-collision projectile. Using constant velocity Ar9+ and N3+, results from four different datasets are presented, with a selection on the final charge state of the projectile (Ar8+ or Ar7+ and N2+ or N+). Three distinct dissociation pathways (I, II, and III) are observed for each dataset, with the mean kinetic energy release values of around 4.7, 5.8, and 7.9 eV, respectively. The electronic states that are populated correspond to electronic configurations (1t2)-2 and (2a1)-1(1t2)-1 of the methane dication, CH4 2+. The relative branching ratios between the three pathways are discussed as a function of the charge state of the post-collision projectile, and a strong correlation with the specific nature of the ion-molecule interaction is found. The existing ab initio calculations have provided an explanation only for pathway II. In this article, we propose an explanation for pathway III, but pathway I still remains unexplained and requires further theoretical efforts. A discussion of the dependence of dissociation on the mode of excitation is presented.

3.
AJNR Am J Neuroradiol ; 42(11): 2054-2061, 2021 11.
Article in English | MEDLINE | ID: mdl-34593378

ABSTRACT

BACKGROUND AND PURPOSE: Selective voluntary motor control is an important factor influencing gross motor function, interjoint coordination, and the outcome of hamstring-lengthening surgery in spastic cerebral palsy. Using DTI, we investigated whether selective voluntary motor control would show strong correlations with WM motor tract microstructure and whether selective voluntary motor control is more sensitive to global WM impairment than gross motor function. MATERIALS AND METHODS: Children with spastic bilateral cerebral palsy born preterm and typically developing children were recruited. The Selective Control Assessment of the Lower Extremity (SCALE) and Gross Motor Function Measure (GMFM) were assessed in participants with cerebral palsy. Participants underwent brain MR imaging to collect DWI data. Tract-Based Spatial Statistics was used to analyze the WM for between-group differences and correlations with SCALE and GMFM. ROI analyses compared motor regions. RESULTS: Twelve children with cerebral palsy (mean age, 11.5 years) and 12 typically developing children (mean age, 10.3 years) participated. Altered DTI outcomes were found throughout the whole brain for the cerebral palsy group. SCALE, developed to evaluate selective voluntary motor control in cerebral palsy, showed significant positive correlations with fractional anisotropy in more WM voxels throughout the whole brain and for motor regions, including the corticospinal tract and corpus callosum, compared with GMFM. A significant negative correlation between radial diffusivity and SCALE, but not GMFM, was found within the corpus callosum. CONCLUSIONS: SCALE was a more sensitive clinical correlate of motor and whole-brain WM tract impairment in children with spastic bilateral cerebral palsy, suggesting greater anisotropy and myelination in these regions for those with higher selective voluntary motor control.


Subject(s)
Cerebral Palsy , White Matter , Brain/diagnostic imaging , Cerebral Palsy/diagnostic imaging , Child , Diffusion Tensor Imaging , Humans , Infant, Newborn , Muscle Spasticity
4.
Auton Neurosci ; 229: 102737, 2020 12.
Article in English | MEDLINE | ID: mdl-33166836

ABSTRACT

Adenosine and nitric oxide act on the fine-tuning regulation of neural cardiovascular control in the nucleus tractus solitarius (NTS). Although the interaction between adenosine and NO is well known in the periphery, the mechanisms by which adenosine interferes in the dynamics of nitrergic neurotransmission, related to neural control of circulation, are not completely understood and might be relevant for individuals predisposed to hypertension. In this study we evaluate the interaction between adenosinergic and nitrergic systems in cell culture from the dorsomedial medulla oblongata of Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHR). Using quantification of nitrite levels, RT-PCR analysis and RNA interference we demonstrate that adenosine A1 (A1R) and A2a receptor (A2aR) agonists induce a concentration-dependent decrease and increase of nitrite and nNOS mRNA levels in cultured cells from WKY and SHR, respectively. These effects in nitrite levels are attenuated by the administration of A1R and A2aR selective antagonists, CPT and ZM 241385. Furthermore, knockdown of A1R and A2aR show an increase and decrease of nNOS mRNA levels, respectively. Pretreatment with the nonselective inhibitor of NOS, L-NAME, abolishes nitrite-increased levels triggered by CGS 21680 in WKY and SHR cells. Finally, it is shown that the cAMP-PKA pathway is involved in A1R and A2aR-mediated decrease and increase in nitrite levels in SHR and WKY cells. Our results highlight the influence of adenosine on nitric oxide levels in cultured cells from dorsal medulla oblongata of neonate WKY and SHR rats. In part, the modulatory profile is different in the SHR strain.


Subject(s)
Adenosine/metabolism , Hypertension/metabolism , Medulla Oblongata/metabolism , Nitric Oxide/metabolism , Nitrites/metabolism , Receptor, Adenosine A1/metabolism , Receptor, Adenosine A2A/metabolism , Animals , Cells, Cultured , Female , Male , Purinergic P1 Receptor Agonists/pharmacology , Purinergic P1 Receptor Antagonists/pharmacology , Rats , Rats, Inbred SHR , Rats, Inbred WKY
5.
Phys Chem Chem Phys ; 21(3): 1587-1596, 2019 Jan 21.
Article in English | MEDLINE | ID: mdl-30620033

ABSTRACT

The radiative cooling of highly excited carbon cluster cations of sizes N = 8, 10, 13-16 has been studied in an electrostatic storage ring. The cooling rate constants vary with cluster size from a maximum at N = 8 of 2.6 × 104 s-1 and a minimum at N = 13 of 4.4 × 103 s-1. The high rates indicate that photon emission takes place from electronically excited ions, providing a strong stabilizing cooling of the molecules.

6.
BMC Res Notes ; 11(1): 257, 2018 Apr 25.
Article in English | MEDLINE | ID: mdl-29695260

ABSTRACT

OBJECTIVE: Guided self-help treatments based on cognitive behavioral therapy (CBT-GSH) are regarded as a first-line effective treatment for bulimia nervosa (BN). With limited application for CBT-GSH in Japanese clinical settings, we conducted a single arm pilot study in order to confirm the acceptability and availability of CBT-GSH in Japan. RESULTS: 25 women with BN received 16-20 sessions of face-to-face CBT-GSH. Primary outcomes were the completion rate of intervention and abstinence rates from objective bingeing and purging as assessed by the Eating Disorder Examination. Secondary outcomes were other self-report measurements of the frequency of bingeing and purging, and characteristic psychopathologies of eating disorders. Assessments were conducted before CBT as baseline as well as after CBT. 92% (23/25) of the participants completed the CBT sessions. After CBT-GSH, 40% (10/25) of the participants (intention-to-treat) achieved symptom abstinence. The mean binge and purge episodes during the previous 28 days improved from 21.88 to 10.96 (50% reduction) and from 22.44 to 10.88 (52% reduction), each (before CBT-GSH to after CBT-GSH), and the within-group effect sizes were medium (Cohen's d = 0.67, 0.65, each). Our study provided a preliminary evidence about the feasibility of CBT-GSH in Japanese clinical settings for the future. Trial registration This study was registered retrospectively in the national UMIN Clinical Trials Registry on July 10, 2013 (registration ID: UMIN000011120).


Subject(s)
Bulimia Nervosa/therapy , Cognitive Behavioral Therapy/methods , Outcome Assessment, Health Care , Self Care/methods , Adolescent , Adult , Feasibility Studies , Female , Humans , Japan , Pilot Projects , Young Adult
7.
Eur J Trauma Emerg Surg ; 44(4): 503-509, 2018 Aug.
Article in English | MEDLINE | ID: mdl-28831501

ABSTRACT

PURPOSE: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is now a feasible and less invasive resuscitation procedure. This study aimed to compare the clinical course of trauma and non-trauma patients undergoing REBOA. METHODS: Patient demographics, etiology, bleeding sites, hemodynamic response, length of critical care, and cause of death were recorded. Characteristics and outcomes were compared between non-trauma and trauma patients. Kaplan-Meier survival analysis was then conducted. RESULTS: Between August 2011 and December 2015, 142 (36 non-trauma; 106 trauma) cases were analyzed. Non-traumatic etiologies included gastrointestinal bleeding, obstetrics and gynecology-derived events, visceral aneurysm, abdominal aortic aneurysm, and post-abdominal surgery. The abdomen was a common bleeding site (69%), followed by the pelvis or extra-pelvic retroperitoneum. None of the non-trauma patients had multiple bleeding sites, whereas 45% of trauma patients did (P < 0.001). No non-trauma patients required resuscitative thoracotomy compared with 28% of the trauma patients (P < 0.001). Non-trauma patients presented a lower 24-h mortality than trauma patients (19 vs. 51%, P = 0.001). The non-trauma cases demonstrated a gradual but prolonged increased mortality, whereas survival in trauma cases rapidly declined (P = 0.009) with similar hospital mortality (68 vs. 64%). Non-trauma patients who survived for 24 h had 0 ventilator-free days and 0 ICU-free days vs. a median of 19 and 12, respectively, for trauma patients (P = 0.33 and 0.39, respectively). Non-hemorrhagic death was more common in non-trauma vs. trauma patients (83 vs. 33%, P < 0.001). CONCLUSIONS: Non-traumatic hemorrhagic shock often resulted from a single bleeding site, and resulted in better 24-h survival than traumatic hemorrhage among Japanese patients who underwent REBOA. However, hospital mortality increased steadily in non-trauma patients affected by non-hemorrhagic causes after a longer period of critical care.


Subject(s)
Aorta , Balloon Occlusion/methods , Shock, Hemorrhagic/prevention & control , APACHE , Adult , Aged , Balloon Occlusion/instrumentation , Female , Hemodynamics , Hospital Mortality , Humans , Injury Severity Score , Japan/epidemiology , Male , Middle Aged , Registries , Retrospective Studies , Shock, Hemorrhagic/mortality , Survival Analysis , Wounds and Injuries/complications , Wounds and Injuries/mortality
8.
Eur J Trauma Emerg Surg ; 44(4): 491-501, 2018 Aug.
Article in English | MEDLINE | ID: mdl-28801841

ABSTRACT

PURPOSE: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is a technique for temporary stabilization of patients with non-compressible torso hemorrhage. This technique has been increasingly used worldwide during the past decade. Despite the good outcomes of translational studies, clinical studies are divided. The aim of this multicenter-international study was to capture REBOA-specific data and outcomes. METHODS: REBOA practicing centers were invited to join this online register, which was established in September 2014. REBOA cases were reported, both retrospective and prospective. Demographics, injury patterns, hemodynamic variables, REBOA-specific data, complications and 30-days mortality were reported. RESULTS: Ninety-six cases from 6 different countries were reported between 2011 and 2016. Mean age was 52 ± 22 years and 88% of the cases were blunt trauma with a median injury severity score (ISS) of 41 (IQR 29-50). In the majority of the cases, Zone I REBOA was used. Median systolic blood pressure before balloon inflation was 60 mmHg (IQR 40-80), which increased to 100 mmHg (IQR 80-128) after inflation. Continuous occlusion was applied in 52% of the patients, and 48% received non-continuous occlusion. Occlusion time longer than 60 min was reported as 38 and 14% in the non-continuous and continuous groups, respectively. Complications, such as extremity compartment syndrome (n = 3), were only noted in the continuous occlusion group. The 30-day mortality for non-continuous REBOA was 48%, and 64% for continuous occlusion. CONCLUSIONS: This observational multicenter study presents results regarding continuous and non-continuous REBOA with favorable outcomes. However, further prospective studies are needed to be able to draw conclusions on morbidity and mortality.


Subject(s)
Aorta , Balloon Occlusion/methods , Registries , Shock, Hemorrhagic/prevention & control , Balloon Occlusion/adverse effects , Female , Humans , Injury Severity Score , Male , Middle Aged , Shock, Hemorrhagic/mortality , Thoracic Injuries/complications , Wounds, Nonpenetrating/complications
9.
Eur J Trauma Emerg Surg ; 44(4): 511-518, 2018 Aug.
Article in English | MEDLINE | ID: mdl-27738726

ABSTRACT

PURPOSE: The aim of this study is to evaluate the early survival and organ damage following 30 and 60 min of thoracic resuscitative endovascular balloon occlusion of the aorta (REBOA) in an ovine model of severe hemorrhagic shock. METHODS: Eighteen sheep were induced into shock by undergoing a 35 % controlled exsanguination over 30 min. Animals were randomized into three groups: 60-min REBOA 30 min after the bleeding (60-REBOA), 30-min REBOA 60 min after the bleeding (30-REBOA) and no-REBOA control (n-REBOA). Resuscitation with crystalloids and whole blood was initiated 20 and 80 min after the induction of shock. Animals were observed for 24 h with serial potassium and lactate measurements. Autopsy was performed to evaluate organ damage. RESULTS: Two animals of the n-REBOA group died within 90 min of shock induction; no hemorrhagic deaths were observed in the REBOA groups. Twenty-four-hour survival for the 60-, 30-, and n-REBOA groups was 0/6, 5/6, and 4/6 (P = 0.002). In 60-REBOA, potassium and lactate were increased at 270-min time point: from 4.3 to 5.1 mEq/l and from 3.7 to 5.1 mmol/L, respectively. Both these values were significantly higher than in the n-REBOA group (P = 0.029 for potassium and P = 0.039 for lactate). Autopsy revealed acute tubular necrosis in all died REBOA group animals. CONCLUSIONS: In this ovine model of severe hemorrhagic shock, REBOA can be used to prevent early death from hemorrhage; however, 60 min of occlusion results in significant metabolic derangement and organ damage that offsets this gain.


Subject(s)
Aorta , Balloon Occlusion/methods , Shock, Hemorrhagic/prevention & control , Animals , Disease Models, Animal , Random Allocation , Resuscitation/methods , Sheep, Domestic , Survival Rate , Time Factors
10.
Phys Rev Lett ; 118(23): 233402, 2017 Jun 09.
Article in English | MEDLINE | ID: mdl-28644649

ABSTRACT

Fragmentation of molecular nitrogen dimers (N_{2})_{2} induced by collision with low energy 90 keV Ar^{9+} ions is studied to evidence the influence of a molecular environment on the fragmentation dynamics of N_{2} cations. Following the capture of three or four electrons from the dimer, the three-body N_{2}^{+}+N^{m+}+N^{n+} [with (m,n)=(1,1) or (1, 2)] fragmentation channels provide clean experimental cases where molecular fragmentation may occur in the presence of a neighbor molecular cation. The effect of the environment on the fragmentation dynamics within the dimer is investigated through the comparison of the kinetic energy release (KER) spectra for these three-body channels and for isolated N_{2}^{(m+n)+} monomer cations. The corresponding KER spectra exhibit energy shifts of the order of 10 eV, attributed to the deformation of the N^{m+}+N^{n+} potential energy curves in the presence of the neighboring N_{2}^{+} cation. The KER structures remain unchanged, indicating that the primary collision process is not significantly affected by the presence of a neighbor molecule.

11.
J Helminthol ; 90(6): 766-772, 2016 Nov.
Article in English | MEDLINE | ID: mdl-26750177

ABSTRACT

Experimental Echinococcus multilocularis infection and deworming was repeated three or five times in nine dogs at various re-infection schedules. The mean number of worms decreased more than 91% in dogs with repeated infection, compared to first infection controls (n= 6). The copro-antigen assay and the egg count in the faeces suggested that the worm burden gradually decreased each time the dogs were re-infected. To examine whether such worm exclusion was a non-specific response, five dogs were sequentially infected with the parasite four times and subsequently fed freely for 6 months. Even after the 6-month interval, the five dogs that were infected five times with the parasite were still able largely to exclude the adult worms. The results suggested that the ability of worm exclusion in dogs that developed a resistance did not become rapidly extinct. Observation of the condition of faeces and the excretion of hooks in the faeces of repeatedly infected dogs revealed that the exclusion of worms started at the first week after the re-infection, and it continued during the patent period. Serum antibodies specific to the parasite antigen increased gradually until the third infection and significantly decreased during the 6-month interval. There was little enhancement of serum antibodies after the fifth infection in most dogs, although no clear correlation was observed between the antibody response and the worm burden. These findings suggested the possibility of developing a vaccine.


Subject(s)
Echinococcosis/drug therapy , Echinococcosis/parasitology , Echinococcus multilocularis/drug effects , Echinococcus multilocularis/immunology , Parasite Load , Animals , Antibodies, Helminth/blood , Antigens, Helminth/analysis , Disease Models, Animal , Dogs , Echinococcus multilocularis/isolation & purification , Feces/parasitology , Parasite Egg Count
12.
Parkinsonism Relat Disord ; 21(10): 1210-3, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26324211

ABSTRACT

INTRODUCTION: Adult-onset dystonias are often segmental in distribution and preferentially affect the craniocervical muscles. Here we describe an overlooked muscle group involved in craniocervical dystonia - the hyoid muscles. Dystonia of these muscles results in anterior neck tightness, speech changes, and dysphagia. METHODS: For this retrospective study we obtained a list of 55 patients who had received botulinum toxin injections into hyoid muscles between 1998 and 2013. Fifteen patients were identified to have an unusual dystonia affecting the hyoid muscles. RESULTS: Patients presented with a triad of speech resonance changes (100%), anterior neck tightness (86.6%), and dysphagia (73.3%). Ten (66.7%) patients presented with all three symptoms, while fourteen (93.3%) had at least two. Fourteen patients (93.3%) had a concomitant dystonia affecting the face or neck and eleven (73.3%) had a sensory trick. Exam universally showed contracted hyoid muscles. Some patients had professions or hobbies requiring prolonged use of vocal muscles such as teachers, singers, and musicians. Patients were often misdiagnosed and received unnecessary treatments. Patients underwent botulinum toxin injections into various hyoid muscles with benefit in 71% of patients but adverse effects in the same proportion. CONCLUSIONS: Hyoid muscle dystonia is a previously poorly characterized focal dystonia causing the triad of speech changes, anterior neck tightness, and dysphagia. Concomitant dystonia, sensory tricks, and visualization of contracted hyoid muscles were often present. Recognition of this disease may reduce unnecessary testing and treatments, and patients may benefit from botulinum toxin injections.


Subject(s)
Botulinum Toxins, Type A/therapeutic use , Dystonic Disorders/complications , Dystonic Disorders/drug therapy , Neuromuscular Agents/therapeutic use , Adult , Aged , Deglutition Disorders/etiology , Female , Humans , Hyoid Bone , Male , Middle Aged , Neck Muscles/pathology , Retrospective Studies , Speech Disorders/etiology
13.
Diagn Interv Imaging ; 96(7-8): 687-91, 2015.
Article in English | MEDLINE | ID: mdl-26119866

ABSTRACT

This article proposes an innovative concept of interventional radiology for hemodynamically unstable trauma patients. Damage control interventional radiology (DCIR) is an aggressive and time-conscious algorithm that prioritizes saving life of the hemorrhaging patient in extremis which conventional emergency interventional radiology (CEIR) cannot efficiently do. Briefly, DCIR aims to save life while CEIR aims to control bleeding with a constant concern to time-awareness. This article also presents the concept of "Prompt and Rapid Endovascular Strategies in Traumatic Occasions" (PRESTO) that entirely oversees and manages trauma patients from arrival to the trauma bay until initial completion of hemostasis with endovascular techniques. PRESTO's "Start soon and finish sooner" relies on the earlier activation of interventional radiology team but also emphasizes on a rapid completion of hemostasis in which DCIR has been specifically tailored. Both DCIR and PRESTO expand the role of IR and represent a paradigm shift in the realm of trauma care.


Subject(s)
Cerebral Hemorrhage, Traumatic/therapy , Embolization, Therapeutic/methods , Emergency Medical Services , Algorithms , Brain Damage, Chronic/diagnosis , Brain Damage, Chronic/prevention & control , Cerebral Hemorrhage, Traumatic/diagnosis , Cooperative Behavior , Early Medical Intervention , Humans , Interdisciplinary Communication , Prognosis , Tomography, X-Ray Computed
14.
Phys Rev Lett ; 114(3): 033201, 2015 Jan 23.
Article in English | MEDLINE | ID: mdl-25658997

ABSTRACT

We provide the experimental evidence that the single electron capture process in slow collisions between O^{3+} ions and neon dimer targets leads to an unexpected production of low-energy electrons. This production results from the interatomic Coulombic decay process, subsequent to inner-shell single electron capture from one site of the neon dimer. Although pure one-electron capture from the inner shell is expected to be negligible in the low collision energy regime investigated here, the electron production due to this process overtakes by 1 order of magnitude the emission of Auger electrons by the scattered projectiles after double-electron capture. This feature is specific to low charge states of the projectile: similar studies with Xe^{20+} and Ar^{9+} projectiles show no evidence of inner-shell single-electron capture. The dependence of the process on the projectile charge state is interpreted using simple calculations based on the classical over the barrier model.

15.
Phys Rev Lett ; 113(14): 143201, 2014 Oct 03.
Article in English | MEDLINE | ID: mdl-25325640

ABSTRACT

Electron capture processes for low energy Ar(9+) ions colliding with Ar(2) dimer targets are investigated, focusing attention on charge sharing between the two Ar atoms as a function of the molecular orientation and the impact parameter. A preference for charge-asymmetric dissociation channels is observed, with a strong correlation between the projectile scattering angle and the molecular ion orientation. The measurements here provide clear evidence that projectiles distinguish each atom in the target and that electron capture from near-site atoms is favored. Monte Carlo calculations based on the classical over-the-barrier model, with dimer targets represented as two independent atoms, are compared to the data. They give new insight into the dynamics of the collision by providing, for the different electron capture channels, the two-dimensional probability maps p(b), where b is the impact parameter vector in the molecular frame.

16.
Phys Rev Lett ; 112(18): 183001, 2014 May 09.
Article in English | MEDLINE | ID: mdl-24856693

ABSTRACT

We report conclusive evidence of an efficient cooling mechanism via the electronic radiative transitions of hot small molecular anions isolated in vacuum. We stored C6(-) and C6H(-) in an ion storage ring and observed laser-induced electron detachment with delays up to several milliseconds. The terminal hydrogen atom caused a drastic change in the decay profiles. The decay of photoexcited C6H(-) is slow and nonexponential, which can be explained by depletion cooling, whereas that for C6(-) occurs extremely fast, on a time scale below 0.1 ms and can only be explained by electronic radiative cooling via low-lying electronic excited states.

17.
J Chem Phys ; 140(10): 104311, 2014 Mar 14.
Article in English | MEDLINE | ID: mdl-24628173

ABSTRACT

The spontaneous and photo-induced neutralization of C7⁻ produced in a laser ablation source was measured in an electrostatic storage ring. The measurements provide three independent determinations of the radiative cooling of the ions, based on the short time spontaneous decay and on the integrated amplitude and the shape of the photo-induced neutralization signal. The amplitude of the photo-induced signal was measured between 0.5 ms and 35 ms and found to depend on photon wavelength and ion storage time. All three signals can be reproduced with identical thermal IR radiative cooling rates with oscillator strengths equal to theoretical predictions. In addition, the measurements provide the excitation energy distribution.

18.
J Perinatol ; 34(5): 375-9, 2014 May.
Article in English | MEDLINE | ID: mdl-24556979

ABSTRACT

OBJECTIVE: Brain injury in preterm infants may lead to an inflammatory response and central nervous system dysfunction reflected by abnormal heart rate characteristics (HRC). We hypothesized that a continuously monitored HRC index reflecting reduced HR variability and decelerations correlates with abnormal neuroimaging and outcomes in extremely low birth weight infants (ELBW). STUDY DESIGN: We analyzed the average HRC index within 28 days after birth (aHRC28) and head ultrasound (HUS) in 384 ELBW infants. In 50 infants with brain magnetic resonance imaging (MRI) and 70 infants with Bayley neurodevelopmental testing at 1 year of age, we analyzed the relationship between aHRC28, MRI abnormalities and low Bayley scores. RESULT: aHRC28 was higher in infants with severe HUS abnormalities (2.65±1.27 for Grade III-IV intraventricular hemorrhage (IVH) or cystic periventricular leukomalacia (cPVL) versus 1.72±0.95 for normal or Grade I-II IVH, P<0.001). Higher aHRC28 was also associated with white matter damage on MRI and death or Bayley motor or mental developmental index <70. Associations persisted after adjusting for gestational age, birth weight and septicemia. For every one point increase in aHRC28, the odds ratio of death or Bayley score <70 was 2.45 (95% CI 1.46, 4.05, P<0.001). CONCLUSION: A continuously monitored HRC index provides an objective, noninvasive measure associated with abnormal brain imaging and adverse neurologic outcomes in ELBW infants.


Subject(s)
Brain Injuries/congenital , Heart Rate/physiology , Infant, Extremely Low Birth Weight/physiology , Neuroimaging , Birth Weight , Brain Injuries/diagnosis , Brain Injuries/diagnostic imaging , Cerebral Hemorrhage/diagnosis , Child Development , Gestational Age , Humans , Infant , Infant, Newborn , Leukomalacia, Periventricular/diagnosis , Magnetic Resonance Imaging , Sepsis , Ultrasonography
19.
Emerg Radiol ; 21(1): 89-92, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24013714

ABSTRACT

Acute cerebellitis is a postinfectious or postvaccinal disorder that predominantly affects children. The typical magnetic resonance imaging appearance has been previously described as cerebellar hemispheric cortical edema. Here, we report a rare case of respiratory syncytial virus-related cerebellitis with transient diffusion restriction of cerebellar peduncles and dentate nucleus. Differential diagnoses are also discussed.


Subject(s)
Cerebellar Diseases/virology , Encephalitis/virology , Respiratory Syncytial Virus Infections/diagnosis , Acute Disease , Cerebellar Diseases/diagnosis , Child, Preschool , Diagnosis, Differential , Electroencephalography , Encephalitis/diagnosis , Female , Humans , Magnetic Resonance Imaging , Spinal Puncture
20.
J Chem Phys ; 139(5): 054306, 2013 Aug 07.
Article in English | MEDLINE | ID: mdl-23927261

ABSTRACT

Photon induced decay of C5(-) has been measured in an electrostatic storage ring. The time dependence of the photo-enhanced decay is close to a 1∕t decay which indicates a thermal process. The deviation from the expected power of -1 is quantitatively explained by the small heat capacity of the anion. Measurements of the photo-enhanced decay at different storage times and photon energies allow a determination of the radiative cooling rate and the energy distribution of the ions. The average energy content between 15 and 70 ms is found to vary as time to the power -0.72, and at 50 ms the ions contain an average excitation energy of 0.5 eV. The time dependent energy distribution is consistent with cooling by infrared photon emission if published oscillator strengths are reduced by a factor 2.5, in contrast to cooling of larger molecular carbon-based ions where electronic transitions cause a much stronger cooling.

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