Temperature-resilient solid-state organic artificial synapses for neuromorphic computing.

Devices with tunable resistance are highly sought after for neuromorphic computing. Conventional resistive memories, however, suffer from nonlinear and asymmetric resistance tuning and excessive write noise, degrading artificial neural network (ANN) accelerator performance. Emerging electrochemical random-access memories (ECRAMs) display write linearity, which enables substantially faster ANN training by array programing in parallel. However, state-of-the-art ECRAMs have not yet demonstrated stable and efficient operation at temperatures required for packaged electronic devices (~90°C). Here, we show that (semi)conducting polymers combined with ion gel electrolyte films enable solid-state ECRAMs with stable and nearly temperature-independent operation up to 90°C. These ECRAMs show linear resistance tuning over a >2× dynamic range, 20-nanosecond switching, submicrosecond write-read cycling, low noise, and low-voltage (±1 volt) and low-energy (~80 femtojoules per write) operation combined with excellent endurance (>109 write-read operations at 90°C). Demonstration of these high-performance ECRAMs is a fundamental step toward their implementation in hardware ANNs.

Ion conductivity through TEMPO-mediated oxidated and periodate oxidated cellulose membranes.

Cellulose in different forms is increasingly used due to sustainability aspects. Even though cellulose itself is an isolating material, it might affect ion transport in electronic applications. This effect is important to understand for instance in the design of cellulose-based supercapacitors. To test the ion conductivity through membranes made from cellulose nanofibril (CNF) materials, different electrolytes chosen with respect to the Hofmeister series were studied. The CNF samples were oxidised to three different surface charge levels via 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), and a second batch was further cross-linked by periodate oxidation to increase wet strength and stability. The outcome showed that the CNF pre-treatment and choice of electrolyte are both crucial to the ion conductivity through the membranes. Significant specific ion effects were observed for the TEMPO-oxidised CNF. Periodate oxidated CNF showed low ion conductivity for all electrolytes tested due to an inhibited swelling caused by the crosslinking reaction.

Predicting death or extended length of stay in infants with congenital diaphragmatic hernia.

OBJECTIVE: To predict mortality or length of stay (LOS) >109 days (90th percentile) among infants with congenital diaphragmatic hernia (CDH). STUDY DESIGN: We conducted a retrospective analysis using the Children's Hospital Neonatal Database during 2010 to 2014. Infants born >34 weeks gestation with CDH admitted at 22 participating regional neonatal intensive care units were included; patients who were repaired or were at home before admission were excluded. The primary outcome was death before discharge or LOS >109 days. Factors associated with this outcome were used to develop a multivariable equation using 80% of the cohort. Validation was performed in the remaining 20% of infants. RESULTS: The median gestation and age at referral in this cohort (n=677) were 38 weeks and 6 h, respectively. The primary outcome occurred in 242 (35.7%) infants, and was distributed between mortality (n=180, 27%) and LOS >109 days (n=66, 10%). Regression analyses showed that small for gestational age (odds ratio (OR) 2.5, P=0.008), presence of major birth anomalies (OR 5.9, P<0.0001), 5- min Apgar score ⩽3 (OR 7.0, P=0.0002), gradient of acidosis at the time of referral (P<0.001), the receipt of extracorporeal support (OR 8.4, P<0.0001) and bloodstream infections (OR 2.2, P=0.004) were independently associated with death or LOS >109 days. This model performed well in the validation cohort (area under curve (AUC)=0.856, goodness-of-fit (GF) χ(2), P=0.16) and acted similarly even after omitting extracorporeal support (AUC=0.82, GF χ(2), P=0.05). CONCLUSIONS: Six variables predicted death or LOS ⩾109 days in this large, contemporary cohort with CDH. These results can assist in risk adjustment for comparative benchmarking and for counseling affected families.

Successful primary use of VVDL+V ECMO with cephalic drain in neonatal respiratory failure.

OBJECTIVE: To describe the use of double-lumen venovenous (VVDL) extracorporeal membrane oxygenation (ECMO) with cephalic draining cannula (VVDL+V) as a primary approach for all neonatal respiratory diagnoses and to compare our single-center experience with data as collected in the Extracorporeal Life Support Organization (ELSO) database. STUDY DESIGN: We retrospectively reviewed all cases of ECMO for neonatal respiratory failure performed in the neonatal intensive-care unit at a large referral children's hospital, the Children's Healthcare of Atlanta at Egleston (CHOA-E). Comparisons were then made to neonatal respiratory ECMO data retrieved from the ELSO database. RESULTS: At CHOA-E 162 of 189 cases were completed with the VVDL+V approach. Survival in the VVDL+V cohort was 89.1% versus 68.7% from ELSO, P<0.001. For those complications considered, the overall risk of complication favored the CHOA-E VVDL+V group as compared with ELSO (odds ratio (OR) 0.71 (0.52-0.7)) as did the risk of neurologic complications (OR 0.29, (0.15-0.58)), including intracranial hemorrhage (OR 0.39 (0.18-0.97), P=0.011). CONCLUSION: The VVDL+V approach can be used successfully as the primary approach for ECMO for neonatal respiratory failure of various etiologies and in this single-center cohort this approach was associated with improved survival and lower rates of complication as compared with the ELSO database.

Early feeding factors associated with exclusive versus partial human milk feeding in neonates receiving intensive care.

OBJECTIVE: To evaluate early feeding factors associated with exclusive human milk (EHM) feeding at discharge in a cohort of human milk-fed infants admitted to the neonatal intensive care unit (NICU). STUDY DESIGN: Retrospective cohort of consecutively discharged infants from two NICUs over a 12-month period who received any human milk during the 24 h before hospital discharge. We used logistic regression to evaluate early feeding factors associated with EHM feeding at discharge. RESULT: We evaluated a total of 264 infants. EHM-fed infants were twice as likely to receive human milk at the first feeding compared with partial human milk-fed infants (65% vs 32%; P<0.01). In multivariable analysis, including adjustment for race and type of maternal insurance, infants receiving human milk as the initial feeding, compared with formula, had a greater odds of EHM feeding at hospital discharge (adjusted odds ratio (OR)=3.41; 95% confidence interval (CI)=1.82 to 6.39; P<0.001). CONCLUSION: Among infants admitted to the NICU whose mothers provide human milk, those receiving human milk as the first feeding were more likely to receive EHM feeding at discharge.

Using metaphor to clarify emerging roles in patient care management teams.

Difficult economic times, competition for scarce resources and changing organizational paradigms are driving health care institutions to re-examine the ways in which they provide care. They must continually strive to provide excellent patient care and ensure positive patient outcomes while responding to increasing fiscal constraint. At Toronto's Hospital for Sick Children, consistent with current trends, nurse managers are asked to take on broad spans of responsibility. The need to decentralize much of the decision making, problem identification and problem solving functions to the multidisciplinary team is a reality of those changes. This paper describes a process the dialysis staff undertook to better understand new organizational imperatives using an orchestra metaphor as a suggestive tool to help people clarify new roles and relationships in organizations that are evolving from a hierarchical model to a knowledge-based team approach to work. The intervention was successful for some people and not others. An analysis of the outcomes is provided from the nurse manager's perspective.

The development and implementation of a respite care program for paediatric peritoneal dialysis patients.

When a child is sent home on peritoneal dialysis, the family is faced with enormous challenges. Despite the coordination of community resources, there are few opportunities for relief from the many tasks required to keep a child home on dialysis. The intensity and duration of the home care required for children awaiting renal transplantation have often led to overwhelming parental stress, marital discord and burn-out. These events can lead to the detriment of the well-being of the child and may result in a higher incidence of peritonitis. Many families had identified the need for some form of relief. Recognizing this, the staff of the home dialysis program of the Toronto Hospital for Sick Children (HSC) joined forces with the staff at Bloorview Children's Hospital (a chronic care/rehabilitation centre) to develop a respite program for these families. The HSC staff provided staff education, medical back-up and financed the equipment and supply costs while the Bloorview Hospital provided the accommodation and the medical and nursing staff to care for the children. In addition to providing parental relief, Bloorview Hospital was able to provide extended care to children requiring peritoneal dialysis until their parents were able to care for them at home. This enabled HSC to use their beds for more acutely ill children. Initial evaluation of the program was favourable and efforts are now being made to streamline the system.

Low-dose and heparin-free hemodialysis in children.

Successful heparin-free hemodialysis has been reported in adults but not in children. A preliminary study was carried out to determine whether heparin-free hemodialysis was possible in children who were considered to have a high risk of bleeding, and if so, to identify the children in whom this technique might be expected to succeed. Of 28 heparin-free procedures, 21 (75%) were successful, a major clot developed in 4, and a minor clot occurred in 3. These children were 6.76 +/- 4.57 years old and weighed 20.7 +/- 11.3 kg. An activated clotting time (ACT) of less than 170 s was recorded in five of the six patients in whom clotting was observed (normal value 146 s with a range of 110-180 s). In a second prospective study, low-dose heparin was prescribed for patients with an ACT of less than 170 s, while the remaining children again underwent heparin-free dialysis. In this study only those patients with double-lumen vascular access and a predialysis systolic blood pressure greater than 80 mmHg were included. Their mean age was 12.25 +/- 4.61 years and their weights 32.9 +/- 19.3 Kg. In 28 of 31 (90%) procedures, no clotting was observed. Minor clotting developed during the remaining 3 procedures, all in one child who weighed 8.5 kg (the only child weighing less than 10 kg). Heparin (9.6 +/- 3.2 IU/kg body weight per hour) was administered during 18 successful procedures. This study shows that heparin-free hemodialysis is possible in children, particularly, but not exclusively, those with a coagulopathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Factors predisposing and contributing to peritonitis during chronic peritoneal dialysis in children: a ten-year experience.

Factors contributing and predisposing to peritonitis were studied retrospectively in 83 children treated with continuous ambulatory (CAPD) or continuous cycling peritoneal dialysis (CCPD) from 1978 to 1988. Recurrent peritonitis was the most frequent complication and the major reason for peritoneal dialysis failure. Fifty patients had 171 episodes of peritonitis during the ten years and 33 remained peritonitis-free. The duration of dialysis was significantly shorter in the peritonitis-free group. The incidence of peritonitis was lower with CCPD than with CAPD. Leucopenia was not a predisposing factor nor was blood leucocytosis helpful in diagnosing peritonitis. Serum IgG was low in 33% of patients with episodes of peritonitis, but there was no correlation or predictive value in this finding. The C3 component of complement was relatively lower than the C4 but both components was relatively lower than the C4 but both components were usually in the normal range. Serum albumin was low in all patients, but lower in those with peritonitis episodes. Age, sex, primary disease, diapers, pyelostomies, dialysis training, and living conditions were not significantly associated risk factors. Sterile dressings gave no benefit over the shower technique. Patient noncompliance, upper respiratory tract infection, skin infections, and dental treatment were potential risk factors. However, peritonitis seemed to be distributed randomly among the patients.

Exit-site infection during continuous and cycling peritoneal dialysis in children.

A 10-year retrospective review of pediatric patients on peritoneal dialysis showed that 50 of 83 had 132 episodes of exit-site infection (ESI). Thirty-nine episodes were purulent. The most prevalent organism was Staphylococcus aureus. Staphylococcus epidermidis was also common, usually occurring in purulent infections. Gram-negative organisms were responsible for 23 ESIs, with Pseudomonas species being the most common. Age, sex, concomitant primary disease type, length of training, dressing techniques, quality of daily dialysis technique, use of diapers, and pyelostomies did not affect the incidence of ESI. However, 40% of children with a skin infection from other sites had associated peritoneal catheter ESI. Thirty-eight episodes of ESI in 28 patients resulted in peritonitis; the main organisms involved were Staphylococcus and Pseudomonas species. Catheters were replaced in 13 patients with peritonitis, but there was no difference in the incidence of ESI before and after catheter replacement.

Electroretinogram parameters at presentation as predictors of rubeosis in central retinal vein occlusion patients.

This report evaluates the prognostic value of parametric electroretinography (ERG) techniques in the development of rubeosis in central retinal vein occlusion (CRVO). An ERG protocol was followed on the initial clinic visit for 21 CRVO patients. None of these patients had neovascular complications or any treatment before the ERG examination. The ERG data were used to define an intensity-response (I-R) function, b-wave to a-wave peak ratio (b/a-wave ratio), and 30-Hz b-wave implicit time. A Naka-Rushton function was fitted to the I-R data to obtain values for maximum saturated response (Rmax) and for the log of the half-saturation intensity (log K). The authors' results show that ERG parameters relating both to the effective number of responding retinal elements and to the sensitivity of responding elements have significant prognostic value. Unexpectedly high predictive values were found for the Rmax and b/a ratio, parameters thought to correlate with the effective number of responding elements, compared with log K and 30-Hz implicit time, parameters thought to relate more closely to retinal ischemia. A multiple discriminant analysis, combining information from these ERG parameters, allowed separation of CRVO patients in whom rubeosis would develop from those in whom it would not, with a false-positive rate of only 14%.

Peritonitis in children undergoing dialysis. 10 years experience.

The clinical aspects of peritonitis were reviewed in 83 patients treated with continuous ambulatory or continuous cyclic peritoneal dialysis between May 1978 and April 1988. Peritonitis occurred in 50 patients whose mean duration of dialysis was 17.8 months, but not in 33 patients with a mean duration of dialysis of 10.4 months. The mean time from starting dialysis to the first episode of peritonitis was 7.1 months. The peritonitis rate was lower for continuous cyclic than for continuous ambulatory peritoneal dialysis (1 episode per 12.9 vs. 1 episode per 8.1 patient months, respectively). In 39% of the episodes, gram stain of the dialysate was positive. The dialysate leukocyte count was higher in gram-negative than in gram-positive peritonitis. Seventy percent of the peritonitis episodes were gram positive, and Staphylococcus aureus was predominant. Only 1 of the 7 diapered infants had gram-negative organisms associated with peritonitis. Catheters were replaced in 48 cases, 26 because of infection. Sixty-nine percent of the patients were cured with antibiotic therapy alone. Although peritonitis was associated with a mortality rate of 1.2%, peritoneal dialysis remains the favored dialytic mode for children.

Effect of respiratory alkalosis during exercise on blood lactate.

A biofeedback model of hyperventilation during exercise was used to assess the independent effects of pH, arterial CO2 partial pressure (PaCO2), and minute ventilation on blood lactate during exercise. Eight normal subjects were studied with progressive upright bicycle exercise (2-min intervals, 25-W increments) under three experimental conditions in random order. Arterialized venous blood was drawn at each work load for measurement of blood lactate, pH, and PaCO2. Results were compared with those from reproducible control tests. Experimental conditions were 1) biofeedback hyperventilation (to increase pH by 0.08-0.10 at each work load); 2) hyperventilation following acetazolamide (which returned pH to control values despite ventilation and PaCO2 identical to condition 1); and 3) metabolic acidosis induced by acetazolamide (with spontaneous ventilation). The results showed an increase in blood lactate during hyperventilation. Blood lactate was similar to control with hyperventilation after acetazolamide, suggesting that the change was due to pH and not to PaCO2 or total ventilation. Exercise during metabolic acidosis (acetazolamide alone) was associated with blood lactate lower than control values. Respiratory alkalosis during exercise increases blood lactate. This is due to the increase in pH and not to the increase in ventilation or the decrease in PaCO2.