Institut Mines-Télécom Business School

This document contains a list of one typo in the main text and six typos in the online appendix of the article. Each typo is followed by an explanation of why it is only a typo and does not affect the analysis in the article. The main text and online appendix refer to the documents in the journal’s website https://www.econometricsociety.org/publications/ econometrica/2021/01/01/preferred-habitat-model-term-structure-interest-rates.

According to the National Institutes of Health, obesity is a major health problem with clearly established health implications, including an increased risk for coronary artery disease, hypertension, dyslipidemia, diabetes mellitus, gallbladder disease, degenerative joint disease, obstructive sleep apnea, and socioeconomic and psychosocial impairment (1). The risk of developing one or more of these obesity-related conditions is based on body mass index (BMI), with 25–30 kg/m2 being low risk and >40 kg/m2 being very high risk (2). The prevalence of obesity in the 18- to 29-yr-old group increased from 12% in 1991 to 18.9% in 1999 (3). Bariatric surgery encompasses a variety of surgical weight loss procedures used to treat morbid obesity. Obesity is clinically expressed in terms of BMI or Quetelet’s index (4), which is derived by dividing weight by the square of height to estimate the degree of obesity. Thus, BMI = body weight (kg)/height2 (m2). Morbid obesity is a BMI more than 35 kg/m2, and super morbid obesity is BMI more than 55 kg/m2. The indications for surgical treatment of severe obesity, as outlined in the 1991 National Institutes of Health Consensus Development Conference Panel, include an absolute BMI more than 40 kg/m2 or BMI more than 35 kg/m2 in combination with life-threatening cardiopulmonary problems or severe diabetes mellitus (1). Patients seeking surgical weight loss must have proven attempts at medically supervised weight loss. Documentation of loss of <5% to 10% excess body weight or weight gain after at least 6 mo of diet modification, exercise, and medical therapy or nonimprovement in comorbid conditions during this period indicates failure. Studies have shown that weight loss of 5%–10% of initial body weight improves glucose intolerance and Type II diabetes, hypertension, and dyslipidemia (5–7). The average expenditure is approximately $7000 per year per patient on weight loss programs and equipment. Unfortunately, long-term weight loss is the exception, and most patients regain weight, sometimes more than they initially lost. Surgical Treatment of Obesity Surgical approaches designed to treat obesity can be classified as malabsorptive or restrictive (8,9). Malabsorptive procedures, which include jejuno-ileal bypass and biliopancreatic bypass, are rarely used at present. Restrictive procedures include the vertical banded gastroplasty (VBG) and gastric banding, including adjustable gastric banding (AGB). RYGB, the “gold standard” of bariatric operations, combines gastric restriction with a minimal degree of malabsorption. VBG, AGB, and RYGB can all be performed laparoscopically (10,11). At our institution, laparoscopic Roux-en-Y gastric bypass (RYGB) is routinely performed on patients weighing <160 kg without other contraindications to laparoscopy, including uncorrected coagulopathy and inability to tolerate laparotomy. Technical considerations and instrumentation technology currently make laparoscopic bariatric surgery difficult in patients weighing >180 kg (8,12). Gastric restriction, or gastroplasty, separates the stomach into a small upper pouch (15–30 mL), which restricts food intake. This pouch communicates with the remainder of the stomach through a narrow channel, or stoma. RYGB (Fig. 1), the most commonly performed bariatric procedure in the United States, involves anastomosing the proximal gastric pouch to a segment of the proximal jejunum, bypassing most of the stomach and the entire duodenum. It is the most effective bariatric procedure to produce safe short-term and long-term weight loss in severely obese patients (13). With RYGB, patients lose an average of 50%–60% of excess body weight and show a decrease in BMI of approximately 10 kg/m2 during the first 12 to 24 postoperative months. To the health care provider, the effect of weight loss on associated weight-related comorbidity is more important than absolute weight loss. Studies have shown that Type II diabetes resolves in up to 90% of patients (14).Figure 1: Roux-en-Y gastric bypass. A, A 15- to 30-mL gastric pouch with connected jejunal limb. B, Site of jejuno-jejunostomy.The variables used to measure surgical outcome include operative time, length of skin incision, estimated blood loss, number of patients requiring intensive care unit stay, length of hospital stay, early and late (>30 days) complications, early (<30 days) reoperation, and weight loss. Using these variables, Nguyen et al. (15) found that, with the exception of length of operative time, laparoscopic RYGB was generally associated with better outcomes and cost-effectiveness than open RYGB. The rate of anastomotic leakage is also slightly more frequent with the laparoscopic approach (8), but it becomes comparable once the learning curve has been mastered (approximately 70 cases) (16). Other advantages of the laparoscopic procedure include reduced hospital stay, more rapid return to normal activity, improved cosmesis, and a marked reduction in the incidence of incisional hernia and wound infection (8,15). There are also smaller postoperative pain medication requirements, less pain intensity during mobilization, and improved pulmonary function. Complications after RYGB include anastomotic leak, gastric pouch outlet obstruction, jejunostomy obstruction, deep vein thrombosis (DVT), pulmonary embolism (PE), respiratory failure, gastrointestinal (GI) bleeding, and wound infection. Late complications include prolonged nausea and vomiting, cholelithiasis, ventral hernia, anemia, and protein-calorie malnutrition. Nguyen et al. (15) discovered, in a prospective, randomized study, that these complications are more common after open RYGB than after laparoscopic RYGB, except for late anastomotic stricture, which was significantly more common after the laparoscopic approach. The more frequent leak rate with laparoscopic RYGB was thought to be related to the learning curve. RYGB induces an undesirable “dumping syndrome” if the patient ingests a high-sugar liquid meal (17), with potential side effects of iron and vitamin B12 malabsorption. Dumping syndrome consists of early postprandial abdominal and vasomotor symptoms resulting from fluid shifts and release of vasoactive neurotransmitters (the pathophysiology of which is peripheral) and splanchnic vasodilation, coupled with a relative hypovolemia, leading to diarrhea and abdominal cramps. It occurs in approximately 10% of patients postgastric bypass surgery. Late dumping symptoms are due to reactive hypoglycemia, which results from an exaggerated insulin and glucagon-like peptide 1 release. Symptoms can be relieved with dietary modifications to minimize the ingestion of simple carbohydrates and to exclude fluid intake during ingestion of the solid portion of the meal. Severe cases may respond to agents such as pectin and guar (plant polysaccharide bulking agents that increase the viscosity of intraluminal contents) or to acarbose, an α-glucosidase inhibitor that blunts the rapid absorption of glucose (18,19). Octreotide, a somatostatin analog that alters gut transit and impairs the release of vasoactive mediators, may also be useful in patients refractory to all other therapy (18). It acts through its inhibitory effects on insulin and gut hormone release, a delay of intestinal transit time, and inhibition of food-induced circulatory changes (19). The AGB (Fig. 2), recently approved by the Food and Drug Administration for use in the United States, is the newest gastric restrictive operation and is usually placed by a minimally invasive laparoscopic approach. It consists of an adjustable inflatable band placed around the proximal stomach to limit oral intake (8). It is a less dynamic operation than RYGB and has a learning curve of 30 operations. Up to 50% ± 28% average excess weight loss has been reported with AGB at 2-yr follow-up, with a complication rate of 19% and a mortality rate of 0.4%(20,21). Band erosion and erosive esophagitis were reported by Westling et al. (22) to be the most common complications requiring repeat surgery over 3 yr. Other complications include herniation of the stomach upward inside of the band and band migration from overfilling (23). In a series of 250 laparoscopic AGB patients by Nehoda et al. (24), the most significant complications were early pouch dilations occurring in the first week; however, the most common complications were disconnections at the portal site between the tube and reservoir. Specific contraindications to AGB include inflammatory diseases of the GI tract (such as severe esophagitis, gastric or duodenal ulcers, or specific inflammation, such as Crohn’s disease), upper GI bleeding (such as esophageal or gastric varices), portal hypertension, congenital or acquired anomalies of the GI tract (e.g., atresias or stenoses), intraoperative gastric injury (e.g., gastric perforation at or near the location of the intended band placement), liver cirrhosis, chronic pancreatitis, and allergy to the materials used to make the band.Figure 2: Adjustable gastric banding. A, Proximal pouch. B, Adjustable band. C, Needle access port through which saline is injected or removed to vary the size of the adjustable band.Medical Therapy for Obesity Approved indications for drug treatment include a BMI of ≥30 kg/m2 or a BMI from 27 and 29.9 kg/m2 in conjunction with an obesity-related medical complication. The combination of phentermine and fenfluramine (Phen-Fen) was the most popular treatment for obesity until it became associated with valvular heart disease and pulmonary hypertension. As a result of this, Phen-Fen is no longer approved by the Food and Drug Administration and should never be used for this purpose. Sibutramine and orlistat are newer antiobesity medications approved for long-term use. Sibutramine inhibits the reuptake of norepinephrine, serotonin, and dopamine, thereby causing anorexia. These mechanisms act synergistically to increase satiety after the onset of eating rather than reduce appetite It the release of serotonin, fenfluramine and which increase the release of in and also the thereby causing These in mechanisms of may have been no of causing valvular the of to with fenfluramine and generally The most frequent effects of treatment include and Sibutramine also in and blood by a of and induces a small increase in heart rate of blood with weight loss, this effect on blood as as is A that of with with of with of initial results in weight loss after approximately 6 mo that is for at least 1 is a of a from that inhibits It and absorption of dietary by in the GI decrease in to the weight loss GI by are the most A decrease in of and has been in approximately of patients with orlistat an average weight loss of with in the group at the of 1 In orlistat has been as a of in and but a has been proven effect may increase orlistat the absorption of vitamin orlistat and to 10% weight with for up to There is a of and on between or orlistat and should be of the side effects of these and effects on body and and liver are common in the but is usually Up to 90% of obese patients show of the with of more than 50% of In a of obese patients for bariatric of which was severe and in to of obese patients without of liver disease have increased liver is the most frequent in the obese reduction in body weight, improves by In a of patients gastric banding increased liver increased by by and by surgery. and to normal after surgery in all the patients in to the of weight reduction after gastric banding. and that in without liver disease, a weight reduction of and of liver recently obese patients intraoperative liver at the of RYGB an rate of with approximately to severe and these and no has been found between liver and the of the liver to of is increased in obesity of increased blood and rate et al. the of obesity on and in and and found that the and effective were increased in with of the of hypertension. et al. up to a increase in in obese this may be an important to the most in these patients Other have also shown in in obese with should on to the obese and the Patients for bariatric surgery should be for hypertension, pulmonary hypertension, of failure, and heart of as increased heart pulmonary and be difficult to The most common symptoms of pulmonary include and which an inability to increase during of with is the most useful of pulmonary may of such as and The the pulmonary artery the more the may show of disease and of pulmonary to pulmonary of and other that may pulmonary may be they and decrease pulmonary With severe pulmonary hypertension, and may be and access and should be during the and the of invasive should be with the blood and for and of and from postoperative Patients for repeat bariatric surgery may the or after the initial the should be with changes in these long-term include vitamin and is in patients with vitamin in patients up with postoperative With rapid weight loss, patients may also be and should be if patient has been or if the patient is vitamin can to an with a normal of of and the of a vitamin such as can be used to the coagulopathy be for surgery or bleeding and It is that the except insulin and oral be until the of surgery. is important of increased risk of postoperative wound infection. of wound infection after gastric for obesity are approximately and after GI surgery are A of open bariatric surgery the infection rate of restrictive procedures vertical gastroplasty, and as that of combination procedures and was Other have wound infection of after open gastric bypass In a prospective, randomized study, Nguyen et al. (15) found that open RYGB an approximately 10 more frequent incidence of wound infection with the laparoscopic approach. The increased incidence of wound infection is due to longer generally longer operative of obesity, from in and inability of to infection however, also by for the laparoscopic approach. and and should be during are for and they or no respiratory can also be in small for during the with (e.g., and (e.g., and (e.g., reduce gastric or thereby the risk and complications of Morbid obesity is a major risk for from postoperative surgery and 12 until the patient was reduced the risk of low weight have in of injected of of for use in the of in patients bariatric surgery. et al. found that 40 12 rather than 30 12 of in a incidence of postoperative complications without an increase in bleeding In the study, et al. of for in patients RYGB and found that the smaller once is safe and and has as the in is currently in the United Studies have shown that is to the once for In a of of the for Bariatric for was the most of by and other In combination with of on the or to and designed or may be for safe for bariatric surgery. have a weight limit of approximately but of up to with a to the are or into Bariatric surgical patients are to the during they should be to the The use of a is also are in and that are with of The patient is on the which is around the and a is to a inside the which to the they It is to that all materials used to are care should be to and are more common in this in the super obese and the and have been reported may be by of the thereby the of the The upper are most by of the to the side may be by prolonged from the injury may if the and has been associated with increased A by et al. such an of patients with in series a BMI kg/m2, with of the The and degree to which a is should be that and can be with the and in this A degree of that results in the segment is It is a from injury of with to months. of the with of and other There is loss of at the injury site and with of and of on the for the of and to is the are of the with of all It a for of this with the of with patient and and injury may in this most with and changes during The most used for this is such as can the changes of is increased with increased The degree of its effects on return and There is a to in At an is an increase in from a reduction in splanchnic of with a increase in and however, blunts this of the occurs at an with return from the body and at an blood and blood can be reduced by and with an increased risk of thrombosis weight on the during causing a reduction in and of surgical and in the upper may the et al. the effect of morbid obesity, and body and on respiratory and during In however, they body to have significant effect on respiratory during reported that, was by increased body weight, respiratory were by obesity and but with body have in which of the and from a tube to be into a and may be by of restriction of from that to of to the of the of can and which can be by complications that should be in include and should be used for the super obese with severe cardiopulmonary disease and for with of the blood of severe of the upper or of can be increased if a small for the is used with that a of of the upper the entire should be used and blood can be from the or with blood in in which occurs with blood use in cases in which access be are for cardiopulmonary for is postoperative which can be in this patient and is more performed in the and of should be for the of a difficult and a with surgical should be A or the and can for an exaggerated from The of this as is to the patient that the of the is at a than the to and et al. used a to the between the of and patient that of a in a patient with a 1 than that of patient are the of the patient with a the of a was approximately with a with a at This as the of such as and show significant in of for obese relative to have or no in with obesity. to this include and which are but which have no between degree of and in obese absolute between obese and and should be on the of body weight 1: of with or can be on the of body weight more body mass These are of an obese increase in body weight can be to an increase in to the estimated of medications is to include the can be in this The of are is for but this is in of such as or has been as the of in this patient of its more rapid and with for use during bariatric surgery and of its more rapid incidence of nausea and vomiting, of and early from the and small and make a during bariatric but high in the obese its use. Obesity and This is due to excess and an increased on and other et al. performed and heart in 10 obese but and that the was increased by up to and increased with body The was however, that to the of excess is during laparoscopic bariatric procedures to and to an for and safe of laparoscopic also the of surgical and of of may be an early that is with the limit for the of the around the the port site may also be a of and has been to better of use of a and for upper abdominal surgery in the obese This most bariatric procedures are performed a minimally invasive laparoscopic with less of postoperative pulmonary improved and less with With the of such as and intraoperative is generally for et al. a of with for intraoperative and postoperative in 27 obese patients for found this to be safe during surgery and effective for postoperative of up to have been as one to in the obese patient This has been shown to may be increased et al. the effects of on and in obese patients during and found that up to increased the and of the without significantly but it in severe that no during of obese patients during in of that the can be by from leading to pulmonary and that reduced in this of it to use of to rather than in an to routinely use of to and respiratory of up to to during laparoscopic bariatric surgery with abdominal have also used with of to and have found that intraoperative fluid are usually if postoperative is to be Patients usually up to of for an average This up to the fluid the based on a period for an average patient for the first by the for the first 10 for the 10 1 for The usually the of after which the are reduced to approximately the based on for the 12 Other Technical of an and tube during surgery to the size the gastric pouch. also leak with saline and to anastomotic should be during of saline or through the tube to that the tube a of can leading to It is also important to all into the gastric to and of these (Fig. an RYGB pouch is the should the in this the should be the tube is to of the of postoperative 1 A, of the tube in the gastric B, placed tube the A incidence of has been reported in obese patients after upper abdominal surgery and of treatment has been in the and to postoperative has also been used to et al. the effect of combination of and on postoperative pulmonary in obese patients during the first 24 after found that therapy with a 12 and significantly reduced pulmonary and the of pulmonary function. The of stomach which is early after gastric was by this et al. recently the of postoperative for patients as of the RYGB between use and the incidence of major anastomotic the risk of anastomotic injury from by a for bariatric patients may deep of and a for abdominal may patients to with early and has been by to postoperative is in this A on the use of in postoperative pulmonary complications to its use during or upper abdominal surgery the 1 reported that deep and were more effective than no treatment in postoperative pulmonary complications after upper abdominal surgery use of laparoscopic for bariatric procedures results in less postoperative pulmonary the for Patients with a of severe sleep may in the intensive care unit prolonged obstructive is a are The pain from an open bariatric surgical procedure can be the are a safe and effective of postoperative in these are also a advantages of in the of bariatric surgery include of improved and of intestinal have been to a in the incidence of and with and however, been as of A at after gastric bypass surgery and found that it postoperative pain with side effects and no of the patients were to oral intake on the postoperative and were by the postoperative on found advantages over in a of and the of postoperative has been used for postoperative after open with and a small incidence of bariatric surgery induces less postoperative pain and is less to with pulmonary laparoscopic bariatric patients with wound and such as In a of patients effective postoperative to was by of or et al. also the of in obese patients RYGB surgery and found that it without effects on blood heart or respiratory function. Patients can be to liquid oral on the first postoperative after has anastomotic or as as they can tolerate with oral or may be but chronic should be of gastric after bariatric Bariatric surgery is a safe and in the of obese patients treatment have been of these patients should into the specific problems associated with obesity and surgery. of medical therapy is at with a loss of 5%–10% body weight at 6 mo to 1 with up to of gastric restriction and bypass or simple gastric restriction have and mortality of and with the most common complications and being respiratory in from to and mortality have been as less frequent (8).

Today’s rapid changing world highlights the influence and impact of technology in all aspects of learning life. Higher Education institutions in developed Western countries believe that these developments offer rich opportunities to embed technological innovations within the learning environment. This places developing countries, striving to be equally competitive in international markets, under tremendous pressure to similarly embed appropriate blends of technologies within their learning and curriculum approaches, and consequently enhance and innovate their learning experiences. Although many universities across the world have incorporated internet-based learning systems, the success of their implementation requires an extensive understanding of the end user acceptance process. Learning using technology (often termed e-learning) has become a popular approach within higher education institutions due to the continuous growth of Internet innovations and technologies. Therefore, this paper focuses on the investigation of students, who attempt to adopt e-learning systems at universities in Jordan. The conceptual research framework of e-learning adoption, which is used in the analysis, is based on the technology acceptance model (TAM). The study also provides an indicator of students’ acceptance of e-learning as well as identifying the important factors that would contribute to its successful use. The outcomes will enrich the understanding of students’ acceptance of e-learning and will assist in its continuing implementation at Jordanian Universities.

BACKGROUND: Small doses of bupivacaine may be a reasonable choice for spinal anesthesia for patients having ambulatory surgery. However, few dose-response data are available to guide the selection of reasonable doses of bupivacaine for different ambulatory procedures. METHODS: Eight volunteers per group were randomized to receive 3.75, 7.5, or 11.25 mg of 0.75% bupivacaine with 8.25% dextrose in a double-blind manner. Sensory block was assessed with pinprick, transcutaneous electrical stimulation equivalent to surgical incision at the ankle, knee, pubis, and umbilicus, and with duration of tolerance to pneumatic thigh tourniquet. Motor block at the quadriceps and gastrocnemius muscles was assessed with isometric force dynamometry. Times until recovery from spinal anesthesia were recorded. Dose-response relationships were determined by linear regressions. Mean (95% confidence intervals) for durations of sensory and motor block per milligram of bupivacaine administered were calculated from linear regressions. RESULTS: Significant dose-response relationships (P < 0.006) were determined for sensory block, motor block, and time until recovery (R from 0.6 to 0.9). Within the range of doses studied, each additional milligram of bupivacaine was associated with an increase in duration of tolerance to transcutaneous electrical stimulation of 10 (7 to 13) min, an increase in tolerance to tourniquet of 7 (2 to 11) min, an increase in duration of motor block of 8 (5 to 12) min, and an increase in time until recovery of 21 (17 to 25) min. CONCLUSIONS: These dose-response data may guide the selection of reasonable doses of bupivacaine for various outpatient procedures, although individual responses vary.

We investigated the structural changes in the left lung of five adult male foxhounds 5 mo (n = 2) or 16 mo (n = 3) after right pneumonectomy (approximately 54% of lung resected) and five sex- and age-matched foxhounds 15-16 mo after right thoracotomy without pneumonectomy. Lungs were fixed by intratracheal instillation of glutaraldehyde and analyzed by standard morphometric techniques. After right pneumonectomy, volume of the left lung increased by 72%. Volumes of all septal structures increased significantly and were more pronounced at 5 than at 16 mo after pneumonectomy. At 16 mo, the relative increases in volume with respect to the control left lung were as follows: epithelium 73%, interstitium 100%, endothelium 55%, and capillary blood volume 43%. Surface areas of alveoli and capillary increased significantly by 52% and 34%, respectively. At 5 mo after pneumonectomy, harmonic mean thickness of the tissue-plasma barrier was significantly greater but at 16 mo it was not different from controls. There was a significant increase in diffusing capacity for oxygen (33% above controls) at 16 mo after pneumonectomy. These data suggest that, in contrast to previous findings after left pneumonectomy, compensatory lung growth does occur in adult dogs after resection of > 50% of lung.

This article develops a rich class of discrete-time, nonlinear dynamic term structure models (DTSMs). Under the risk-neutral measure, the distribution of the state vector X t resides within a family of discrete-time affine processes that nests the exact discrete-time counterparts of the entire class of continuous-time models in Duffie and Kan (1996) and Dai and Singleton (2000). Under the historical distribution, our approach accommodates nonlinear (nonaffine) processes while leading to closed-form expressions for the conditional likelihood functions for zero-coupon bond yields. As motivation for our framework, we show that it encompasses many of the equilibrium models with habit-based preferences or recursive preferences and long-run risks. We illustrate our methods by constructing maximum likelihood estimates of a nonlinear discrete-time DTSM with habit-based preferences in which bond prices are known in closed form. We conclude that habit-based models, as typically parameterized in the literature, do not match key features of the conditional distribution of bond yields. The Author 2010. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oxfordjournals.org, Oxford University Press.

Does strategic planning enhance or impede innovation and firm performance? The current literature provides contradictory views. This study extends the resource-advantage theory to examine the conditions in which strategic planning increases or decreases the number of new product development projects and firm performance. The authors test the theoretical model by collecting data from 227 firms. The empirical evidence suggests that more strategic planning and more new product development (NPD) projects lead to better firm performance. Firms with organizational redundancy benefit more from strategic planning than firms with less organizational redundancy. Increasing R&D intensity boosts both the number of NPD projects and firm performance. Strategic planning is more effective in larger firms with higher R&D intensity for increasing the number of NPD projects. The results reported in this study also consist of several findings that challenge the traditional views of strategic planning. The evidence suggests that strategic planning impedes, not enhances, the number of NPD projects. Larger firms benefit less, not more, from strategic planning for improving firm performance. Larger firms do not necessarily create more NPD projects. Increasing organizational redundancy has no effect on the number of NPD projects. These empirical results provide important strategic implications. First, managers should be aware that, in general, formal strategic planning decreases the number of NPD projects for innovation management. Improvised rather than planned activities are more conducive to creating NPD project ideas. Moreover, innovations tend to emerge from improvisational processes, during which the impromptu execution of NPD activities without planning spurs “thinking outside the box,” which enhances the process of creating NPD project ideas. Therefore, more flexible strategic plans that accommodate potential improvisation may be needed in NPD management since innovation-related activities cannot be planned precisely due to the unexpected jolts and contingencies of the NPD process. Second, large firms with high levels of R&D intensity can overcome the negative effect of strategic planning on the number of NPD projects. Specifically, a firm's abundant resources, when allocated and deployed for NPD activities, signal the high priority and importance of the NPD activities and thus motivate employees to acquire, collect, and gather customer and technical knowledge, which leads to creating more NPD projects. Finally, managers must understand that managing strategic planning and generating NPD project ideas are beneficial to the ultimate outcome of firm performance despite the adverse relationship between strategic planning and the number of NPD projects.

STUDY DESIGN: A case-control study. OBJECTIVES: 1) To determine if hemodilution adequately meets the transfusion needs in children who undergo posterior spinal fusion for idiopathic scoliosis and 2) to compare the efficacy of the various methods used to reduce the risk of allogeneic blood transfusion at the authors' institution. SUMMARY OF BACKGROUND DATA: Methods to reduce blood loss and avoid allogeneic blood transfusion caused by extensive spinal surgery in adolescents include 1) autologous blood predonation, 2) controlled hypotensive anesthesia, 3) intraoperative salvage of shed blood (cell saver), 4) acute normovolemic hemodilution, and 5) transfusion decisions by clinical judgment rather than by a preset value of hemoglobin. Although all methods have some efficacy, it is not clear which methods, separate or combined, are best in the adolescent scoliosis population. METHODS: Hemodilution, hypotensive anesthesia, and cell saver were used in 43 children between June 1996 and July 1997. A comparison group (43 children) underwent similar surgery with hypotensive anesthesia and cell saver, but no hemodilution (between July 1995 and December 1996). These two groups were similar with respect to means of age, levels of instrumentation, magnitude of curvature, estimated blood volume, mean arterial pressure, duration of surgery, duration of anesthesia, estimated blood loss, volume returned from cell saver, volume in the hemovac drain, and length of hospitalization. The groups differed in preoperative hemoglobin and hematocrit and in volume of crystalloid used. RESULTS: Transfusions were given to 34 of 43 patients (79%) in the nonhemodilution group. These patients received 61 units of packed cells (57 autologous, 2 donor directed, and 2 allogeneic). In comparison, 16 of 43 patients (37%) in the hemodilution group required transfusion. They received 16 units of packed cells (15 autologous and 1 allogeneic). There was no significant difference between the groups with respect to postoperative hemoglobin and hematocrit immediately after surgery (hemodilution, 10.2/29.2; nonhemodilution, 10.0/29.1), postoperative day 1 (hemodilution, 9.2/26.9; nonhemodilution, 9.2/27.3), and postoperative day 2 (hemodilution 9.0/26.4; nonhemodilution, 9.2/27.1). There were non complications related to the technique of hemodilution in the 43 patients of this group. Cell saver was used in all patients, but sufficient volume to return blood to the patient was available in only 23 hemodilution patients (mean volume, 230 mL) and 25 nonhemodilution patients (mean volume, 215 mL). In only two patients of each group (< 5%) did the volume returned prevent the absolute need for additional transfusions. CONCLUSIONS: Hemodilution was safely used as a method to satisfy the perioperative transfusion requirements of adolescents undergoing extensive spinal surgery. By allowing patients to arrive at surgery with a higher preoperative hemoglobin and hematocrit, and by decreasing the quantity of predonated autologous blood-collected and therefore used, the hemodilution method may indirectly decrease the quantity of postoperative autologous transfusions in this population. Cell saver was not shown to be effective, and its selective use is recommended.

To assess the effect of hemodialysis on protein metabolism, leucine flux was measured in seven patients before, during, and after high efficiency hemodialysis using cuprophane dialyzers and bicarbonate dialysate during a primed-constant infusion of L-[1-13C]leucine. The kinetics [mumol/kg per h, mean +/- SD] are as follows: leucine appearance into the plasma leucine pool was 86 +/- 28, 80 +/- 28, and 85 +/- 25, respectively, before, during, and after dialysis. Leucine appearance into the whole body leucine pool, derived from plasma [1-13C]alpha-ketoisocaproate enrichment, was 118 +/- 31, 118 +/- 31, and 114 +/- 28 before, during, and after dialysis, respectively. In the absence of leucine intake, appearance rate reflects protein degradation, which was clearly unaffected by dialysis. Leucine oxidation rate was 17.3 +/- 7.8 before, decreased to 13.8 +/- 7.8 during, and increased to 18.9 +/- 10.3 after dialysis (P = 0.027). Leucine protein incorporation was 101 +/- 26 before, was reduced to 89 +/- 23 during, and returned to 95 +/- 23 after dialysis (P = 0.13). Leucine net balance, the difference between leucine protein incorporation and leucine release from endogenous degradation, was -17.3 +/- 7.8 before, decreased to -28.5 +/- 11.0 during, and returned to -18.9 +/- 10.3 after dialysis (P < 0.0001). This markedly more negative leucine balance during dialysis was accountable by dialysate leucine loss, which was 14.4 +/- 6.2 mumol/kg per h. These data suggest that hemodialysis using a cuprophane membrane did not acutely induce protein degradation. It was, nevertheless, a net catabolic event because protein synthesis was reduced and amino acid was lost into the dialysate.

INTRODUCTION: A prospective audit of neonates, infants, and children receiving opioid infusion techniques managed by pediatric acute pain teams from across the United Kingdom and Eire was undertaken over a period of 17 months. The aim was to determine the incidence, nature, and severity of serious clinical incidents (SCIs) associated with the techniques of continuous opioid infusion, patient-controlled analgesia, and nurse-controlled analgesia in patients aged 0-18. METHODS: The audit was funded by the Association of Paediatric Anaesthetists (APA) and performed by the acute pain services of 18 centers throughout the United Kingdom. Data were submitted weekly via a web-based return form designed by the Document Capture Company that documented data on all patients receiving opioid infusions and any SCIs. Eight categories of SCI were identified in advance, and the reported SCIs were graded in terms of severity (Grade 1 (death/permanent harm); Grade 2 (harm but full recovery and resulting in termination of the technique or needing significant intervention); Grade 3 (potential but no actual harm). Data were collected over a period of 17 months (25/06/07-25/11/08) and stored on a secure server for analysis. RESULTS: Forty-six SCIs were reported in 10 726 opioid infusion techniques. One Grade 1 incident (1 : 10,726) of cardiac arrest occurred and was associated with aspiration pneumonitis and the underlying neurological condition, neurocutaneous melanosis. Twenty-eight Grade 2 incidents (1 : 383) were reported of which half were respiratory depression. The seventeen Grade 3 incidents (1 : 631) were all drug errors because of programming or prescribing errors and were all reported by one center. CONCLUSIONS: The overall incidence of 1 : 10,000 of serious harm with opioid infusion techniques in children is comparable to the risks with pediatric epidural infusions and central blocks identified by two recent UK national audits (1,2). Avoidable factors were identified including prescription and pump programming errors, use of concurrent sedatives or opioids by different routes and overgenerous dosing in infants. Early respiratory depression in patients with specific risk factors, such as young age, neurodevelopmental, respiratory, or cardiac comorbidities, who are receiving nurse-controlled analgesia or continuous opioid infusion suggests that closer monitoring for at least 2 h is needed for these cases. As a result of this audit, we can provide parents with better information on relative risks to help the process of informed consent.

Abstract The emerging information revolution makes it necessary to manage vast amounts of unstructured data rapidly. As the world is increasingly populated by IoT devices and sensors that can sense their surroundings and communicate with each other, a digital environment has been created with vast volumes of volatile and diverse data. Traditional AI and machine learning techniques designed for deterministic situations are not suitable for such environments. With a large number of parameters required by each device in this digital environment, it is desirable that the AI is able to be adaptive and self-build (i.e. self-structure, self-configure, self-learn), rather than be structurally and parameter-wise pre-defined. This study explores the benefits of self-building AI and machine learning with unsupervised learning for empowering big data analytics for smart city environments. By using the growing self-organizing map, a new suite of self-building AI is proposed. The self-building AI overcomes the limitations of traditional AI and enables data processing in dynamic smart city environments. With cloud computing platforms, the self-building AI can integrate the data analytics applications that currently work in silos. The new paradigm of the self-building AI and its value are demonstrated using the IoT, video surveillance, and action recognition applications.

BACKGROUND: Incomplete sensory blockade of the foot after sciatic nerve block in the popliteal fossa may be related to the motor response that was elicited when the block was performed. We investigated the appropriate motor response when a nerve stimulator is used in sciatic nerve block at the popliteal fossa. METHODS: Six volunteers classified as American Society of Anesthesiologists' physical status I underwent 24 sciatic nerve blocks. Each volunteer had four sciatic nerve blocks. During each block, the needle was placed to evoke one of the following motor responses of the foot: eversion, inversion, plantar flexion, or dorsiflexion. Forty milliliters 1.5% lidocaine was injected after the motor response was elicited at < 1 mA intensity. Sensory blockade of the areas of the foot innervated by the posterior tibial, deep peroneal, superficial peroneal, and sural nerves was checked in a blinded manner. Motor blockade was graded on a three-point scale. The width of the sciatic nerve and the orientation of the tibial and common peroneal nerves were also examined in 10 cadavers. RESULTS: A significantly greater number of posterior tibial, deep peroneal, superficial peroneal, and sural nerves were blocked when inversion or dorsiflexion was seen before injection than after eversion or plantar flexion (P < 0.05). Motor blockade of the foot was significantly greater after inversion. Anatomically, the tibial and common peroneal nerves may be separate from each other throughout their course. The sciatic nerve ranged from 0.9-1.5 cm in width and was divided into the tibial and common peroneal nerves at 8 +/- 3 (range, 4-13) cm above the popliteal crease. CONCLUSIONS: Inversion is the motor response that best predicts complete sensory blockade of the foot. Incomplete blockade of the sciatic nerve may be a result of the size of the sciatic nerve, to separate fascial coverings of the tibial and common peroneal nerves, or to blockade of either the tibial or common peroneal nerves after branching from the sciatic nerve.

Purpose The authors investigate household acceptance of central bank digital currencies (CBDCs) by drawing on the unified theory of acceptance and use of technology and institutional trust theory. Design/methodology/approach The authors build a research model including six hypotheses and quantitatively analyze it using partial least squares structural equation modeling (PLS-SEM) and importance–performance map analysis (IPMA) based on 282 answers to a survey questionnaire. Findings The continuous adoption of CBDCs by households is highly probable and is fostered by its expected high performance, the social recommendations and the existence of facilitating conditions. Nevertheless, institutions' efforts to propose a flexible and understandable currency can benefit its adoption only if these institutions also strive to build households' trust in the currency's system. Originality/value The authors provide a full review of the emerging literature on CBDCs and suggest that digital currency offerings can be divided into centralized, semi-centralized and de-centralized control in a meaningful taxonomy. The authors also complement extant studies on CBDCs that mostly apprehend its operational challenges by focusing on the customer side and provide implications to the launching of CBDCs by uncovering the customer-specific determinants of their adoption.

Governance issues, here interpreted as the provisions of adequate policy frameworks characterized by reliability and accountability, coupled with resources to support their implementation, are known to be the basis for the implementation of sustainable development measures. This paper discusses the influence of governance in the ways sustainability is perceived and practiced in a higher education context. Apart from due considerations to the role of governance as the basis for regulation and institutional actions and management decisions, this paper reports on an empirical study undertaken in a sample of higher education institutions. This study entailed an analysis of sustainable development policies, certification, organizational structure, budget, reports, team for sustainability, staff training, and challenges for the integration of sustainability and governance. The results suggest that even though there are different opinions and attitudes on the role of governance, it is regarded as an important component in supporting efforts by higher education institutions to include considerations on sustainable development as part of their strategies.

To the Editor: We read with interest the letter of Steegers and Robertson [1]. The authors report pain on injection of subparalyzing doses of rocuronium. We agree with the authors that injection of rocuronium can cause pain that may sometimes be severe. The factors that may affect the degree of pain are the site of injection, the dose of rocuronium, and prior administration of drugs such as midazolam, opioids, and lidocaine. We have noted that administration of midazolam, 2 mg, and fentanyl, 100 micro g, prior to rocuronium, 0.06 mg/kg, prevents the pain on injection. Steegers and Robertson suggest that rocuronium is not suitable for administration prior to succinylcholine or for priming. However, we have used rocuronium, 0.06 mg/kg, prior to succinylcholine [2] and for priming [3] without complaints of pain on injection. This suggests that, with adequate precautions, the pain on injection can be avoided. Girish P. Joshi, MBBS, MD, FFARCSI Charles W. Whitten, MD Department of Anesthesiology and Pain Management; University of Texas Southwestern Medical Center at Dallas; Dallas, TX 75235-9068

Urban living labs have become a popular phenomenon in today’s cities. The Living Lab approach would provide real life research with its multiple stakeholders in a co-innovating inclusive setting, crucial in creating metropolitan solutions with impact, that will be adopted smoothly and swiftly by all involved, and thus help achieve prosperous living environments that are more liveable, sustainable, resilient and just. With these ambitions, urban living labs are important links in the achievement of the goals of AMS Institute as well as the City of Amsterdam. But what exactly are urban living labs?&lt;br/&gt;The aim of the research was to develop a methodology to facilitate systematic achievement of the living lab goals and ambitions in practice. How do urban living labs work? How can they contribute to a more sustainable environment? And how can you set up a successful urban living lab?&lt;br/&gt;Based on a literature review of living labs and urban living labs and a quick scan of 90 local innovation projects in the Amsterdam region, defining characteristics of urban living labs have been identified.Also the core methodological components of urban living labs have been distilled from proposed living lab methodologies and process aspects repetitively referred to in urban living lab literature. In-depth case studies of the innovation processes of innovations that have emerged in living labs in Amsterdam have been conducted to research how urban living labs work in practice. This has led to conditions that have shown to be necessary for allowing successful emergence, implementation and replication of innovations in urban context.

BACKGROUND: Electrical stimulation of peripheral nerves produces acute analgesic effects. This randomized, sham-controlled, crossover study was designed to evaluate the effect of differing durations of electrical stimulation on the analgesic response to percutaneous electrical nerve stimulation in 75 consenting patients with low back pain. METHODS: All patients received electrical stimulation for four different time intervals (0, 15, 30, and 45 min) in a random sequence over the course of an 11-week study period. All active percutaneous electrical nerve stimulation treatments were administered using alternating frequencies of 15 and 30 Hz three times per week for 2 consecutive weeks. The prestudy assessments included the health status survey short form questionnaire and 10-cm visual analog scale scores for pain, physical activity, and quality of sleep, with 0 being the best and 10 being the worst. The pain scoring was repeated 5-10 min after each 60-min study session and 24 h after the last treatment session with each of the four methods. The daily oral analgesic requirements were assessed during each of the four treatment blocks. At the end of each 2-week treatment block, the questionnaire was repeated. RESULTS: Electrical stimulation using percutaneously placed needles produced short-term improvements in the visual analog scale pain, physical activity, and quality of sleep scores, and a reduction in the oral analgesic requirements. The 30-min and 45-min durations of electrical stimulation produced similar hypoalgesic effects (48+/-21% and 46+/-19%, respectively) and were significantly more effective than either 15 min (21+/-17%) or 0 min (10+/-11%). The 30- and 45-min treatments were also more effective in improving physical activity and sleep scores over the course of the 2-week treatment period. In contrast to the sham treatment (0 min), the health status survey short form revealed that electrical stimulation for 15 to 45 min three times per week for 2 weeks improved patient function. CONCLUSION: The recommended duration of electrical stimulation with percutaneous electrical nerve stimulation therapy is 30 min.

In Brief In this prospective, randomized, observer-blinded clinical trial, we compared the incidence of unwanted lower extremity motor blockade and the analgesic efficacy between small-dose (0.125%; 0.2 mg · kg−1 · h−1) postoperative epidural infusions of bupivacaine (Group B; n = 28), levobupivacaine (Group L; n = 27), and ropivacaine (Group R; n = 26) in children after hypospadias repair. Motor blockade and pain were assessed at predetermined time points during 48 h by using a modified Bromage scale and the Children’s and Infant’s Postoperative Pain Scale (CHIPPS). Postoperative analgesia was almost identical in all three study groups (CHIPPS range, 0–3), with no need for the administration of supplemental analgesia in any patient. However, significantly more patients in Group B (n = 6; P = 0.03) displayed signs of unwanted motor blockade during the observation period compared with Group L (n = 0) and Group R (n = 0). In conclusion, significantly less unwanted motor blockade was associated with postoperative epidural infusions of 0.125% levobupivacaine or ropivacaine in children after hypospadias repair as compared with a similar infusion of bupivacaine. However, no difference with regard to postoperative analgesia could be detected among the three different local anesthetics studied. IMPLICATIONS: The use of the newer local anesthetics levobupivacaine and ropivacaine was associated with similar postoperative analgesia but less unwanted muscle weakness of the lower extremities compared with the previous standard (bupivacaine) when administered as small-concentration (0.125%; 0.2 mg · kg−1 · h−1) postoperative epidural infusions in children.

Investors face significant barriers in evaluating the performance of investment advisors. We focus on commodity trading advisors (CTAs) and show that from 1994 to 2012, CTA excess returns to investors (i.e., net of fees) were insignificantly different from zero while gross excess returns (i.e., before fees) were 6.1%, which implies that managers captured the performance in fees. Moreover, we find that CTAs display no alpha relative to simple future strategies in the public domain. Our results have implications for all hedge fund studies in that we find the typical adjustments for biases in the hedge fund databases still leave upward bias in fund performance.

Chronic or recurrent pain in children and adolescents, for which no specific cause can be found, is very common with a point prevalence of at least 15%. 1 Such idiopathic pain conditions are usually "benign" in the sense that they are