Isothermal microcalorimetry as a tool to study solid-electrolyte interphase formation in lithium-ion cells.

Isothermal microcalorimetry can be used in conjunction with electrochemical measurements to study solid-electrolyte interphase (SEI) formation reactions as they occur in a Li-ion cell. The heat flow was measured in wound cells that contained no electrolyte additives and in cells prepared with four additives that are known to produce an SEI at the negative electrode surface: vinylene carbonate (VC), fluoroethylene carbonate (FEC), pyridine boron trifluoride (PBF), and prop-1-ene-1,3-sultone (PES). For VC, two distinct features in the differential capacity (dQ/dV vs. Q) plot that align with overlapping peaks in the heat flow plot do not agree with a simple one-electron reduction followed by anionic polymerization. For FEC, three distinct differential capacity and calorimetric peaks are observed. Heat flow measurements at multiple PBF concentrations show that PBF reduction does not significantly affect the reduction of EC at higher cell voltage. The total heat flow during SEI formation in PBF- and PES-containing cells match the calculated energies in recently published reaction pathways. It is concluded that IMC may be used to study the underlying chemistry of SEI formation, especially when paired with computational studies.

Inpatient Early Intervention for Serious Mental Illnesses Is Associated With Fewer Rehospitalizations Compared With Treatment as Usual in a High-volume Public Psychiatric Hospital Setting.

OBJECTIVE: High-acuity publicly funded inpatient psychiatric settings usually feature short lengths of stay and high readmission rates. This study examined the influence of an early intervention program for serious mental illnesses (SMI) on readmissions at 6 and 12 months postdischarge at a high-volume, urban public inpatient psychiatric hospital. METHODS: The Early Onset Treatment Program (EOTP) is a cost-free, 90-day inpatient multidisciplinary service intervention program for uninsured patients who are within 5 years of SMI onset, funded as a pilot program by the Texas state legislature. Rehospitalization rates at 6 and 12 months were extracted from electronic medical records for EOTP participants (n=165) and comparison patients matched on demographics and diagnosis (n=155). The comparison group received treatment as usual at the same psychiatric hospital. Group re-admission rates were compared using logistic and Poisson regression analyses. RESULTS: Group membership was a significant predictor of rehospitalization (P<0.0001) at both 6 and 12 months. Expressed as 1/odds ratio (OR), the EOTP group was less likely to readmit once and more than once at 6 months postdischarge (1/OR=3.82 and 4.74, respectively) compared with the non-EOTP group. The EOTP group was also less likely to readmit once and more than once at 12 months postdischarge (1/OR=2.96 and 3.51, respectively). CONCLUSIONS: The results suggest that participation in the EOTP service in this high-acuity setting was significantly related to reduced likelihood of rehospitalization at 6 and 12 months. Several variables may account for this observation, including length of stay, longer medication adherence, environmental stability, and more individualized and extensive psychotherapy treatment.

Staged gamma knife radiosurgery for large cerebral arteriovenous malformations.

BACKGROUND: We present our experience over a 10-year period of staged radiosurgery for large arteriovenous malformations (AVMs) including patient outcomes and methods. METHODS: From July 2000 to December 2010, 80 patients with AVMs were treated with gamma knife radiosurgery (GKS) at our institution; of these patients, 5 were treated for large AVMs with staged GKS (volumes >20 cm(3)). The mean interval between treatments was 10 months (range 7-16). The mean dose for the margin used was 18.0 Gy (range 16-20). The mean volume treated was 37.2 cm(3) (range 22-50). The mean total follow-up was 76.5 months (range 42-120). RESULTS: Two patients had complete obliteration of the AVM nidus. One patient had 95% obliteration (31 months after radiosurgery), one had 90% obliteration (38 months after radiosurgery), and one had less than 50% obliteration at 53 months with a 16-month interval between staged treatments. CONCLUSIONS: Staged radiosurgery is an effective and safe method for the treatment of large AVMs. We report achieving higher marginal doses with staging in planned intervals of 6-9 months between staged treatments. It appears that the longer the wait between treatments, the less likely it is that complete obliteration will be achieved.

Inpatient early intervention for serious mental illnesses and post-discharge criminal involvement in a high-volume psychiatric hospital setting.

Individuals with serious mental illness (SMI) are at increased risk for arrest and incarceration relative to the same-community population without SMI. Publicly-funded inpatient psychiatric hospitals usually feature short lengths of stay and limited opportunities for extended services that might impact criminal justice involvement after discharge. This study examined the influence of an early intervention program for SMI at a high-volume public psychiatric hospital on involvement in the criminal justice system post-discharge. The Early Onset Treatment Program (EOTP) is an extended service intervention program for uninsured patients who are within 5 years of SMI onset. Criminal justice records (number of arrests with conviction, days of incarceration) were obtained for EOTP participants (n = 164) and comparison patients (n = 164) matched on demographics, diagnosis, and discharge date via propensity score matching. Data were zero-inflated and analyzed using hurdle models, controlling for prior arrests. The EOTP group was less likely to be convicted of at least one crime post-discharge (0 arrests vs. > 0, p < .001), and spent fewer days incarcerated (if incarcerated ≥1 day, p < .03). Participation in the EOTP service was linked to reduced likelihood of post-discharge arrest and days incarcerated. Several alternative variables may contribute to this preliminary observation, including length of stay, medication adherence, longer environmental stability, and individual patient characteristics.

Previously unreported structure associated with Sprengel deformity.

Congenital elevation of the scapula (Sprengel deformity) is the most common congenital abnormality involving the scapula. In up to 50% of cases, there is an associated connection, which may be osseous, cartilaginous, or fibrous, between the scapula and the lower cervical spine. To date, there have been no reports of an osseous structure extending from the medial scapula to the clavicle and occipital region of the skull associated with Sprengel deformity.

A data science approach to predicting patient aggressive events in a psychiatric hospital.

Recent advances in data science were used capitalize on the extensive quantity of data available in electronic health records to predict patient aggressive events. This retrospective study utilized electronic health records (N = 29,841) collected between January 2010 and December 2015 at Harris County Psychiatric Center, a 274-bed safety net community psychiatric facility. The primary outcome of interest was the presence (1.4%) versus absence (98.6%) of an aggressive event toward staff or patients. The best-performing algorithm, penalized generalized linear modeling, achieved an area under the curve = 0.7801. The strongest predictors of patient aggressive events included homelessness (b = 0.52), having been convicted of assault (b = 0.31), and having witnessed abuse (b = -0.28). The algorithm was also used to generate a cost-optimized probability threshold (6%) for an aggressive event, theoretically affording individualized hospital-staff coverage on the 2.8% of inpatients at highest risk for aggression, based on available hospital operating costs. The present research demonstrated the utility of a data science approach to better understand a high-priority event in psychiatric inpatient settings.

Assessment and cost comparison of sleep-deprived EEG, MRI and PET in the prediction of surgical treatment for epilepsy.

Our aim was to determine if less expensive interictal indices can predict which epilepsy patients may benefit from the more expensive comprehensive pre-surgical evaluation. Surgical treatment was determined based on the results of a comprehensive inpatient continuous video-EEG monitoring. This evaluation included three interictal tests, which were reviewed retrospectively-2 hour-sleep-deprived electroencephalogram (SDEEG), magnetic resonance imaging (MRI), and positron emission tomography (PET). Sixty-nine patients were evaluated with 35 patients having focal resection (33 temporal, two frontal). When two or more interictal tests were positive, 77% (27 /35) went to surgery, but when one test was positive 23% (8 /34) had surgery. When all tests were negative, only a single patient (1 /13 or 7.7%) had surgery, a frontal resection. The positive predictive value for any single interictal test was 68%, while it was higher for any combination of two positive tests (77-83%). PET was the most sensitive (0.86) single interictal test, compared to SDEEG (0.66) and MRI (0.66). The odds ratio for predicting surgical treatment for a positive PET, SDEEG, or MRI was 8.57, 4.01, and 4.01, respectively. MRI was three and PET was six times the cost of a SDEEG. The combination of SDEEG and MRI had the best cost/PPV ratio. Seventy-nine percent (11 /14) of the patients with three positive tests were seizure free following focal resection compared to 43% (9 /21) when less than three tests were positive ( P

Concurrent orthopedic and neurosurgical procedures in pediatric patients with spinal deformity.

The management of pediatric patients with complex spinal deformity often requires both an orthopedic and a neurosurgical intervention. The reasons for multiple subspecialty involvement include, but are not limited to, the presence of a tethered cord requiring release or a syrinx requiring decompression. It has been common practice to perform these procedures in a staged manner, although there is little evidence in the literature to support separate interventions. We reviewed a series of consecutive patients who underwent spinal deformity correction and a neurosurgical intervention concurrently in an attempt to assess the safety, efficacy, and possible complications associated with such an approach. Eleven patients were reviewed who underwent concurrent orthopedic and neurosurgical procedures. Data were collected for patient demographics, preoperative diagnosis, procedures performed, intraoperative and perioperative complications, as well as any unexpected return to the operating room for any reason. Operative notes and anesthesia records were reviewed to determine estimated blood loss, surgical time, and the use of intraoperative neurological monitoring. Patient diagnoses included myelodysplasia (N=6), congenital scoliosis and/or kyphosis (N=4), and scoliosis associated with Noonan syndrome (N=1). Age at the time of surgery averaged 9 years 2 months (range=14 months to 17 years 2 months). Estimated blood loss averaged 605 ml (range=50-3000 ml). The operative time averaged 313 min (range=157-477 min). There were no intraoperative complications, including incidental dural tears or deterioration in preoperative neurological status. One patient developed a sore associated with postoperative cast immobilization that led to a deep wound infection. It appears that concurrent orthopedic and neurosurgical procedures in pediatric patients with significant spinal deformities can be performed safely and with minimal intraoperative and postoperative complications when utilizing modern surgical and neuromonitoring techniques. Level of evidence=Level IV.

Dynamic spring mediated cranioplasty in an experimental model with resorbable foot plates.

Craniofacial surgery continues to be progressive in its approach to maximize function and aesthetic appearance while minimizing risks and complications. Dynamic springs are one way to minimize invasiveness while achieving favorable results. The purpose of this study was to show the safety and efficacy of dynamic springs with resorbable foot plates for treatment of metopic suture abnormalities in a swine model. The study population consisted of twelve 20 kg Chester swine. The swine were divided into two treatment groups: four in the sham surgery group and eight in the stainless steel spring group. Postoperative analysis consisted of evaluation of the skull growth over time and integrity of the foot plates and underlying dura. The swine, killed at 8 weeks, were examined for spring location in the foot plates, ease of removal of the spring, and postmortem histologic analysis of the bone growth. No morbidity or mortality occurred in the immediate perioperative period secondary to the surgery. Postmortem histologic analysis revealed no infections or complications related to the surgery. Statistical analysis using a mixed linear model with an unstructured variance-covariance matrix was fit. In conclusion, this study confirms the efficacy and safety of the spring-mediated cranioplasty at the metopic suture with use of resorbable foot plates in a swine model.

Spring-mediated cranial reshaping for craniosynostosis.

The evolution of modern craniofacial surgery has come full circle from the early strip craniectomies to the complete calvarial remodeling and now back to attempts at minimally invasive surgical interventions. The goal of the craniofacial surgeon has always been the correction of form and function with minimization of associated morbidity and mortality. Particularly problematic has been the ability to maintain the anatomical correction beyond the result seen on the operating room table secondary to changes with growth. The ability to improve the clinical result in a growing and developing child has been the impetus for dynamic treatment modalities. Dr Claes Lauritzen's pioneering work in this area has been particularly successful using internal springs to correct craniofacial deformities. The purpose of this study is to assess this treatment modality clinically in terms of safety and efficacy and to develop a methodology for the spring formation that would be easily reproducible. This is an institutional review board-approved prospective study of 15 children (11 male, 4 female) with non-syndromic sagittal suture synostosis. All patients were treated with a sagittal strip craniectomy and placement of 2 omega-shaped stainless steel springs at a mean age of 3.9 months. Patients were followed clinically and with cephalograms; after reossification of the intervening bone, the springs were removed at a mean age of 8.2 months. The mean force applied at initial placement of the springs was 6.9 N, and the mean spring deflection at formation was 6.87 cm. All patients completed the study protocol without any significant morbidity or any mortality. Perioperative variables, including blood loss, transfusion rate, operative time, intensive care unit stay, hospital stay, and hospital charges, were all significantly less (P < 0.05) in this study group compared with children with the same diagnosis treated with cranial vault reshaping during the same period. Furthermore, the preoperative mean cephalic index of 64.3 corrected to 77.6 after surgery and was maintained over time. Spring-mediated cranial reshaping is efficacious and safe for the treatment of sagittal synostosis. Long-term study of cranial development and clinical morphology are ongoing to validate further the effectiveness of this treatment modality.