A definitive number of atoms on demand: controlling the number of atoms in a-few-atom magneto-optical trap

A few 85Rb atoms were trapped in a micron-size magneto-optical trap with a high quadrupole magnetic-field gradient and the number of atoms was precisely controlled by suppressing stochastic loading and loss events via real-time feedback on the magnetic field gradient. The measured occupation probability of single atom was as high as 99%. Atoms up to five were also trapped with high occupation probabilities. The present technique could be used to make a deterministic atom source.Comment: 3 pages, 4 figure

Common peroneal nerve palsy following total hip arthroplasty: prognostic factors for recovery.

BACKGROUND: Common peroneal nerve palsy, although rare, is a serious complication of total hip arthroplasty. Although several publications have dealt with the risk factors for peroneal nerve palsy, there is little literature regarding the time it takes for the nerve to recover and the factors that influence its recovery. The purpose of this study was to elucidate the clinical course of this injury and identify prognostic factors for recovery. METHODS: From January 2000 to December 2007, 7969 primary and 1601 revision total hip arthroplasties were performed at our institution. Common peroneal nerve palsy developed following thirty-one (0.32%) of these procedures. Thirty of these patients were evaluated by a neurologist at the time of diagnosis and at regular intervals thereafter. Univariate and multivariate regression analyses were performed to identify risk factors and prognostic factors for recovery. RESULTS: On average, patients who developed common peroneal nerve palsy were significantly younger (fifty-six years) than those who did not develop palsy (sixty-three years, p \u3c 0.05). Higher body mass index (BMI) was a negative prognostic factor for recovery from palsy (p \u3c 0.05). The palsy was incomplete in twenty-five of the thirty patients, and fourteen of these recovered fully at a mean of 10.3 months (range, 1.0 to 50.0 months). Three of the five patients with complete nerve palsy recovered fully at a mean of 14.5 months (range, 8.0 to 21.0 months). CONCLUSIONS: Only one-half of the patients in the study who developed common peroneal nerve palsy following total hip arthroplasty recovered fully. The mean time to recovery was approximately one year for partial peroneal palsy and one and one-half years for complete palsy. Obesity adversely influenced the nerve recovery

Calibration of second-order correlation functions for non-stationary sources with a multi-start multi-stop time-to-digital converter

A novel high-throughput second-order-correlation measurement system is developed which records and makes use of all the arrival times of photons detected at both start and stop detectors. This system is suitable particularly for a light source having a high photon flux and a long coherence time since it is more efficient than conventional methods by an amount equal to the product of the count rate and the correlation time of the light source. We have used this system in carefully investigating the dead time effects of detectors and photon counters on the second-order correlation function in the two-detector configuration. For a non-stationary light source, distortion of original signal was observed at high photon flux. A systematic way of calibrating the second-order correlation function has been devised by introducing a concept of an effective dead time of the entire measurement system.Comment: 7 pages, 6 figure

In Vivo Analysis of Three-Dimensional Dynamic Scapular Dyskinesis in Scapular or Clavicular Fractures

The three-dimensional (3D) kinematics of the scapula were analyzed in vivo in 10 patients with scapular and 10 patients with clavicular fracture. Both the injured shoulder and normal contralateral shoulder were evaluated by computed tomography in the neutral and fully elevated positions. 3D rotational and translational movements of the scapula relative to the thorax during arm elevation were analyzed. A computer simulation program was used to compare rotational elevation/depression in the coronal plane, anterior/posterior tilting in the sagittal plane and protraction/retraction in the axial plane between the normal and affected sides. Anterior/posterior translational movement along the X-axis, upward/downward movement along the Y-axis, and lateral/medial movement along the Z-axis in the Euler space during forward elevation were also compared. In scapular fracture, rotational elevation of the scapula decreased in the coronal plane and posterior tilting of the scapula increased in the sagittal plane. Anterior and superior translation were higher in scapular fracture than in the corresponding normal sides. However, no significant abnormal rotational and translational kinematic changes were observed during elevation in clavicular fracture. In vivo 3D computerized motion analysis was useful for evaluating scapular dyskinesis. Scapular fracture can cause scapular dyskinesis, but not all clavicular fractures alter scapular motion biomechanics

Predictors of perioperative blood loss in total joint arthroplasty.

UNLABELLED: UPDATE The print version of this article has errors that have been corrected in the online version of this article. In the Materials and Methods section, the sentence that reads as During the study period, our institution offered preoperative autologous blood donation to all patients who were scheduling for total joint arthroplasty with a hemoglobin level of no less than 11 mg/dL or a hematocrit level of at least 33%. in the print version now reads as During the study period, our institution offered preoperative autologous blood donation to all patients who were scheduling for total joint arthroplasty with a hemoglobin level of no less than 11 g/dL or a hematocrit level of at least 33%. in the online version. In Table III, the footnote that reads as The values are given as the estimate and the standard error in milligrams per deciliter. in the print version now reads as The values are given as the estimate and the standard error in grams per deciliter. in the online version. BACKGROUND: Despite advances in surgical and anesthetic techniques, lower-extremity total joint arthroplasty is associated with considerable perioperative blood loss. As predictors of perioperative blood loss and allogenic blood transfusion have not yet been well defined, the purpose of this study was to identify clinical predictors for perioperative blood loss and allogenic blood transfusion in patients undergoing total joint arthroplasty. METHODS: From 2000 to 2008, all patients undergoing unilateral primary total hip or knee arthroplasty who met the inclusion criteria were enrolled in the study. Perioperative blood loss was calculated with use of a previously validated formula. The predictors of perioperative blood loss and allogenic blood transfusion were identified in a multivariate analysis. RESULTS: Eleven thousand three hundred and seventy-three patients who underwent total joint arthroplasty, including 4769 patients who underwent total knee arthroplasty and 6604 patients who underwent total hip arthroplasty, were evaluated. Multivariate analysis indicated that an increase in blood loss was associated with being male (263.59 mL in male patients who had undergone total hip arthroplasty and 233.60 mL in male patients who had undergone total knee arthroplasty), a Charlson Comorbidity Index of \u3e3 (293.99 mL in patients who had undergone total hip arthroplasty and 167.96 mL in patients who had undergone total knee arthroplasty), and preoperative autologous blood donation (593.51 mL in patients who had undergone total hip arthroplasty and 592.30 mL in patients who had undergone total knee arthroplasty). In patients who underwent total hip arthroplasty, regional anesthesia compared with general anesthesia reduced the amount of blood loss. The risk of allogenic blood transfusion increased with the amount of blood loss in the patients who underwent total hip arthroplasty (odds ratio, 1.43 [95% confidence interval, 1.40 to 1.46]) and the patients who underwent total knee arthroplasty (odds ratio, 1.47 [95% confidence interval, 1.42 to 1.51]), but the risk of blood transfusion increased with the Charlson Comorbidity Index only in patients who underwent total knee arthroplasty (odds ratio, 3.2 [95% confidence interval, 1.99 to 5.15]). The risk of allogenic blood transfusion decreased with preoperative autologous blood donation in patients who underwent total hip arthroplasty (odds ratio, 0.01 [95% confidence interval, 0.01 to 0.02]) and patients who underwent total knee arthroplasty (odds ratio, 0.02 [95% confidence interval, 0.01 to 0.03]). CONCLUSIONS: This study identified some clinical predictors for blood loss in patients undergoing total joint arthroplasty that we believe can be used for implementing more effective blood conservation strategies. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence

Common peroneal nerve palsy following total knee arthroplasty: prognostic factors and course of recovery.

Common peroneal nerve palsy (CPNP) is a serious complication following total knee arthroplasty (TKA). There is little information regarding the clinical course and prognostic factors for recovery. Between January 2000 and December 2008, 44 patients (0.53%) developed CPNP following TKA and were matched to 100 control patients based on year of surgery, type of surgery and surgeon. Regression analysis was performed to identify prognostic factors for recovery. A significant difference was seen in CPNP patients who were on average younger (62.1 years) and had higher BMI (34.5 kg/m(2)) than those who did not have nerve palsy (67.5 years and 31.8 kg/m(2), respectively). Only 37 patients with palsies could be followed, 32 (62.2%) had incomplete nerve palsy, twenty four (75%) of them fully recovered, while only 1 of patients with complete nerve palsy fully recovered. More severe initial injury was a negative prognostic factor for recovery of palsy (P\u3c0.03)

Multimodality Imaging Can Help to Doubt, Diagnose and Follow-Up Cardiac Mass

Primary cardiac lymphoma is a very rare form of lymphoma primarily or mainly involving the heart, as in the two cases presented in this report. Various imaging modalities, including coronary computed tomography angiography, cardiac magnetic resonance imaging and positron emission tomography were useful for the characterization and diagnosis of cardiac mass. Pathologic confirmation was successful with endomyocardial biopsy under echocardiographic guidance, intra- and extracardiacally. In primary cardiac lymphoma, diagnosis using multiple modalities may be useful for mass characterization, and for response monitoring after chemotherapy

Rotational and Varus Instability in Chronic Lateral Ankle Instability: In Vivo 3D Biomechanical Analysis

We retrospectively evaluated the altered biomechanics of the talus in 15 adult patients (7 males, 8 females) with chronic lateral ankle instability when the ankle joint moved actively from full dorsiflexion to full plantarflexion under a non-weight bearing condition. CT images were taken for the unstable ankle and the contralateral normal (control) ankle. Three-dimensional surface models of both ankle joints were reconstructed from the CT data, and we used a computer simulation program to compare both ankle motions of inversion/eversion in the coronal plane, plantarflexion/dorsiflexion in the sagittal plane, and internal rotation/external rotation in the axial plane. This evaluation method provides in vivo, dynamic, and 3D results of ankle motion. In the ankles with chronic lateral instability and the controls, the average talar rotational movement of inversion (+)/eversion (−) was 19.0° and 15.5° and the internal rotation (+)/external rotation (−) was 30.4° and 20.7°, respectively. Paired t-tests revealed significant differences in the amount of inversion (+)/eversion (−) (p=0.012) and internal rotation (+)/external rotation (−) (p<0.001) between unstable and normal ankle joints. The difference of mean rotational movement in internal rotation (9.7°) was greater than that of inversion (3.5°). Rotational instability should be considered when evaluating chronic lateral ankle instability