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The dynamic random access memory (DRAM) disturb known as rowhammer (RH) has come to dominate the insecurity of computing systems worldwide. Several studies have concentrated on electron injection from a switching cell select transistor and capture by nearby storage node junctions as being the main mechanism for the effect. This article for the first time looks in-depth at RH from the point of view of both electron injection and capture, and capacitive crosstalk. The absence of such comprehensive studies at the silicon level in the literature can be attributed to its sensitive nature within the industry and highlights the difficulty of DRAM scaling. This review article, therefore, forms a broad foundation to extend understanding of this dangerous disturb mechanism and in so doing provides an informed view on the ability of future DRAM technologies to solve RH once and for all.

A new dynamic random access memory (DRAM) memory cell transistor is fabricated, and its soft-error immunity and rowhammer tolerance are studied. The vertical channel is formed by selective epitaxial growth of silicon pillar, and the surround gate forms a fully depleted (FD) channel, which can suppress floating-body effects, such as hysteresis. A TCAD simulation study compares this device and conventional bulk saddle FinFET in terms of soft error immunity and rowhammer tolerance. The confined channel limits soft error because of its thin channel volume for charge generation due to alpha and neutron particles. The surround gate device is inherently free from rowhammer attack as each silicon body of any memory cell transistor is fully isolated from neighboring word lines.

Objective Evaluate impact of balloon-assisted deep small bowel enteroscopy on red blood cell transfusion requirement in patients with obscure gastrointestinal (GI) bleeding. Methods Retrospective study of patients, who underwent balloon-assisted deep enteroscopy with double-balloon enteroscopy (DBE) at two tertiary care academic centers (University of Wisconsin and Aurora St. Luke’s Medical Center) over a 55-month consecutive period. Sixty-nine patients with reliable blood transfusion records were identified during this time period. DBE was preceded by small bowel capsule endoscopy (CE) within 1 year in 38 cases. Transfusion requirements 6 months prior and postintervention were measured to see if DBE had any impact on the need for blood transfusions. Results Sixty-nine patients (25 females and 44 males) were included. Mean age ± standard deviation (SD) was 63 ± 17 years. Wilcoxon signed rank test statistics were used to find the difference in the rate of blood transfusion. There was a statistically significant decrease in rate of packed red blood cell (pRBC) transfusion post DBE and endoscopic therapy with coagulation (p < 0.001). Argon plasma coagulation was used to ablate all arteriovenous malformations (AVMs) except in one (subepithelial lesion). Those that required > 5 units pRBC transfusions pre-DBE had the most benefit. Conclusions Our study demonstrates that transfusion requirements are significantly reduced in those undergoing therapy with DBE and coagulation for obscure GI bleed.

Background and Objectives: Rectal endoscopic ultrasound (RUS) has become an essential tool in the management of rectal adenocarcinoma because of the ability to accurately stage lesions. The aim of this study was to identify the staging agreement of early RUS-staged rectal adenocarcinoma with surgical resected pathology and ultimately determine how this impacts the management of early rectal cancer (T1–T2). Methods: Retrospective chart review was performed from November 2002 to November 2013 to identify procedure indication, RUS staging data, surgical management, and postoperative surgical pathology data. Results: There were a total of 693 RUS examinations available for review and 282 of these were performed for a new diagnosis of rectal adenocarcinoma. There was staging agreement between RUS and surgical pathology in 19 out of 20 (95%) RUS-staged T1 cases. There was staging agreement between RUS and surgical pathology in 3 out of 9 (33%) RUS-staged T2 cases. There was significantly better staging agreement for RUS-staged T1 lesions compared to RUS staged T2 lesions (P = 0.002). Nearly 60% of T1N0 cancers were referred for transanal excisions (TAEs), and 78% of T2N0 cancers underwent low anterior resection. Conclusions: This study identified only a small number of T1–T2 adenocarcinomas. There was good staging agreement between RUS and surgical pathology among RUS-staged T1 lesions whereas poor staging agreement among RUS-staged T2 lesions. Although TAE is largely indicated by the staging of a T1 lesion, this approach may be less appropriate for T2 lesions due to high reported local recurrence.

Patients with Roux-en-Y gastric bypass (RYGB) develop pancreatobiliary issues after surgery. Endoscopic management via the conventional route with endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) is quite limited due to the altered anatomy. Laparoscopic-assisted ERCP (LA-ERCP) via the excluded stomach has been highly successful. Reported use of laparoscopic-assisted EUS (LA-EUS) is extremely rare. A retrospective review was conducted at two tertiary referral centers for cases that involved laparoscopic-assisted ERCP and EUS. Patient demographic data were collected along with data regarding procedure, indication, complications and length of stay. A total of 16 cases involving 15 patients were identified: 11 cases of LA-ERCP and five cases of combined LA-EUS plus LA-ERCP were performed. Four patients had previously undergone failed endoscopy via the conventional route (27 %). There was a 100 % biliary/pancreatic cannulation and intervention rate. There were no endoscopic-related complications. Therapeutic interventions included laparoscopic cholecystectomy, lysis of adhesions, biliary and pancreatic sphincterotomy, biliary and pancreatic stent placement, stone removal including mechanical lithotripsy and EUS biopsy and diagnosis of pancreatic cancer. Average discharge was on postoperative day 3.4. However, 50 % were discharged after 1 day. LA-ERCP and combined LA-EUS plus LA-ERCP are safe and highly successful diagnostic and therapeutic modalities for a wide variety of pancreatobiliary ailments in RYGB patients.

Scaling challenges with NAND flash have forced manufacturers to consider monolithic 3-D process and device architectures as potential successor technologies. Those that involve a vertical cylindrical channel are regarded as favorites. These include bit-cost scalable (BiCS) NAND, pipe-shaped bit-cost scalable (p-BiCS) NAND, and terabit cell array transistor (TCAT) NAND. It has been assumed that their manufacturing costs decrease monotonically with the number of additional device layers. This paper presents a rigorous analysis of this assumption based on recently reported challenges associated with the construction of these architectures. It is shown that there is a minimum in die cost after which costs increase with increasing device layers. Also, achievable die sizes using these approaches may not even reach existing production NAND Flash. An important consequence is that monolithic 3-D approaches that involve more lithography-intensive steps may actually result in lower total cost provided that these scale appropriately.

Introduction: The present study aimed to explore how athletes respond to different behaviors of their opponents. Methods: Twelve moderately to highly physically active participants with at least two years of cycling experience completed four 4-km time trials on a Velotron cycle ergometer. After a familiarization time trial (FAM), participants performed three experimental time trials in randomized order with no opponent (NO), a virtual opponent who started slower and finished faster compared to FAM (OP-SLOWFAST), or a virtual opponent who started faster and finished slower compared to FAM (OP-FASTSLOW). Repeated-measures ANOVAs (P < 0.05) were used to examine differences in pacing and performance related to power output, velocity and RPE. Results: OP-SLOWFAST and OP-FASTSLOW were completed faster compared to NO (385.5 ± 27.5, 385.0 ± 28.6, and 390.6 ± 29.3 s, respectively). An interaction effect for condition × distance (F = 3.944, P < 0.001) indicated differences in pacing profiles between conditions. Post-hoc analysis revealed that a less aggressive starting strategy was adopted in NO compared to OP-FASTSLOW and OP-SLOWFAST during the initial 1000 m. Finally, a faster starting opponent evokes higher power outputs by the participants in the initial 750 m compared to a slower starting opponent. Conclusion: The present study is the first to show that the behavior of an opponent affects pacing-related decisions in laboratory-controlled conditions. Our findings support the recently proposed interdependence of perception and action, and emphasize the interaction with the environment as an important determinant for an athlete's pacing decisions, especially during the initial stages of a race.

The aim of this study was to evaluate the detection of colonic neoplasia in an average-risk population of SOT recipients. Studies regarding colonic neoplasia in solid organ transplantation (SOT) recipients have demonstrated mixed results due to the inclusion of above average-risk patients. We performed a case-control study of 102 average-risk SOT recipients who underwent screening colonoscopy, compared with an average-risk, age and sex-matched control group (n=287). Cancer rates were compared with an age-matched cohort from the National Cancer Institute's Survival, Epidemiology, and End Results (SEER) database. There was no difference in number of patients with adenomas (P=1.00). There was no difference in polyps per patient (P=0.31). Although the number of advanced lesions (excluding adenocarcinoma) between groups did not differ (P=0.25), there were two adenocarcinomas identified in the SOT group and none in the control group (P=0.068). Detection of colorectal cancer was an unexpected finding in the SOT cohort and was more likely when compared to age-matched cancer incidence generated by the SEER database. These results suggest no increased adenoma detection in SOT recipients, but with more cases of colorectal cancer than anticipated. Given previous, larger, transplant database studies demonstrating increased colorectal cancer rates, more frequent screening may be justified.

Accurate staging of esophageal cancer (ECA) is critical in determining appropriate therapy. Endoscopic ultrasound (EUS), computed tomography (CT) and positron emission tomography (PET) scanning can be used, but limited data exists regarding the use of combined PET/CT fusion imaging and EUS in ECA staging. The objective of this study is to evaluate the role of integrated PET/CT imaging and EUS in the staging of ECA.Identification of patients diagnosed with ECA from 2004 to 2007 that underwent staging PET/CT and EUS. Data regarding tumor detection, lymph node identification, presence of metastatic disease, and affect on patient management were collected and compared between PET/CT and EUS.Eighty-one patients (65 male, 16 female) were identified with mean age of 63.5 years who underwent EUS and PET/CT to stage known ECA. PET/CT identified the primary tumor in 74/81 (91.4%) of cases, compared to 81/81 (100%) with EUS. Locoregional adenopathy was seen by PET/CT in 29/81 (35.8%) of cases, compared to 49/81 (60.5%) by EUS (p = 0.0001). PET/CT identified celiac axis adenopathy in 8/81 (9.9%) of cases, compared to 11/81 (13.6%) with EUS (p = 0.5050). PET/CT identified 17/81 (21.0%) of patients with distant metastases who subsequently did not undergo attempt at curative surgical resection.In ECA, EUS is superior to PET/CT for T staging and in identifying locoregional nodes, while PET/CT provides M staging. EUS and integrated PET/CT appear to independently affect treatment decisions, indicating complimentary and necessary roles in the staging of ECA.

There is currently great discrepancy in the training requirements between medical societies regarding the recommended threshold number of colonoscopies needed to assess for technical competence. Our goal was to determine the number of colonoscopies performed by surgical residents, rate of cecal intubation, as well as trainee perceptions of colonoscopy training after completion of their training period. This study consisted of a 12-item electronic survey completed by 21 surgical residents after their 2-month endoscopy rotation at a tertiary care, urban referral center. This survey assessed numbers of colonoscopies performed, number successful to the cecum, and perceptions of training in colonoscopy. The cecal intubation rate was used as a surrogate marker of technical competence. Twenty-one surgical residents performed a mean of 80 ± 35 total colonoscopies during the 2-month rotation. The average cecal intubation rate was 47% (range 9–78%). Resident comfort level for independently performing a total colonoscopy was scored a mean 3.6 on scale of 1–5 (5 = most comfortable), and 43% of the surgical residents planned on performing colonoscopy after residency training. Surgical residents can obtain the recommended threshold for colonoscopy (N = 50) during a standard 2-month rotation. However, no resident was able to achieve technical competence in colonoscopy as defined by a 90% cecal intubation rate. These data suggest that the method of training of general surgery residents in colonoscopy may need reappraisal.

Control of trace inorganics and an understanding of reaction kinetics and impurity generation proved critical in allowing safe and reliable scale-up of a high-temperature Claisen reaction in support of multikilogram manufacture of a key chromene intermediate 4. Implementation of a Medicinal Chemistry route allowed for rapid early phase delivery of 1 to support early clinical studies.

Background & Aims On the basis of the Next Accreditation System, trainee assessment should occur on a continuous basis with individualized feedback. We aimed to validate endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) learning curves among advanced endoscopy trainees (AETs) by using a large national sample of training programs and to develop a centralized database that allows assessment of performance in relation to peers. Methods ASGE recognized training programs were invited to participate, and AETs were graded on ERCP and EUS exams by using a validated competency assessment tool that assesses technical and cognitive competence in a continuous fashion. Grading for each skill was done by using a 4-point scoring system, and a comprehensive data collection and reporting system was built to create learning curves by using cumulative sum analysis. Individual results and benchmarking to peers were shared with AETs and trainers quarterly. Results Of the 62 programs invited, 20 programs and 22 AETs participated in this study. At the end of training, median number of EUS and ERCP performed/AET was 300 (range, 155–650) and 350 (125–500), respectively. Overall, 3786 exams were graded (EUS, 1137; ERCP-biliary, 2280; ERCP-pancreatic, 369). Learning curves for individual end points and overall technical/cognitive aspects in EUS and ERCP demonstrated substantial variability and were successfully shared with all programs. The majority of trainees achieved overall technical (EUS, 82%; ERCP, 60%) and cognitive (EUS, 76%; ERCP, 100%) competence at conclusion of training. Conclusions These results demonstrate the feasibility of establishing a centralized database to report individualized learning curves and confirm the substantial variability in time to achieve competence among AETs in EUS and ERCP. ClinicalTrials.gov: NCT02509416.

The supply route to GlaxoSmithKline’s 5HT4 receptor agonist 1 centred on the construction of key benzopyran fragment 2. Our attempts to define the final manufacturing route for this component are described through a series of disconnections. The systematic approach undertaken towards the construction of the benzopyran skeleton focused on cyclisation strategies from appropriate precursors and evaluation of the performance of the key steps.

Background Diarrhea is common in solid organ transplant recipients. Colonoscopy with random biopsies is performed frequently in the diagnostic evaluation of the posttransplant population with diarrhea. The purpose of this study was to determine the sensitivity of colonoscopy with random biopsy in determining a specific diagnosis and changing management in solid organ transplant recipients with diarrhea. Methods From October 1996 to June 2008, 88 patients were identified who had undergone solid organ transplantation and subsequently underwent colonoscopy for an indication of "diarrhea." These patient's electronic medical records were reviewed to determine patient demographics, laboratory results, findings on colonoscopy and histopathology, and any subsequent diagnoses made and management changes in relation to the diarrhea. Results Eighty-eight patients (mean age 54 years, 65% male) underwent colonoscopy a mean of 69 months after transplantation. Abnormal colonoscopic findings were seen in 16 (18.2%) patients. Histopathology was abnormal in 17/80 (21.3%). However, only eight (9.1%) had findings on colonoscopy or pathologic condition that led to specific diagnosis being made. In addition, only nine (10.2%) patients had a change in medical management as a direct result of colonoscopy with biopsy. Conclusion Although colonoscopic or histopathologic abnormalities are common in the solid organ transplant recipient with diarrhea, the findings rarely lead to a specific diagnosis or management change. Colonoscopy with biopsy should be performed only after noninvasive testing for infectious diarrhea and a thorough review and adjustment of medications. In many patients, a trial of antidiarrheal medication is warranted before colonoscopy.

Established methods for testing ESD robustness of high-voltage pins in smart power CMOS can lead to erroneous results. This paper investigates both LDNMOS and certain types of SCRLDMOS (SCRs embedded in LDNMOS) high-voltage clamps for safe-operating-area collapse due to trigger voltage (V t1) walk-in after transmission-line pulsing (TLP) corresponding to leakage-current increase below I t2. For the first time, the evolution of V t1 as a function of the number of TLP pulses and their magnitude is shown. Furthermore, some high-voltage clamps that are robust on their own are shown to walk-in in certain circuit environments that present high capacitance. The physical mechanism for this leakage enhancement and trigger-voltage walk-in has been established through failure analysis to be consistent with melt filament growth perhaps aided by metal migration. A simple phenomenological model is proposed to explain this behavior. Finally, the ability to avoid such V t1 collapse in SCRLDMOS through simple layout changes is shown.

Background and Objectives: Development of symptomatic pseudocysts after acute pancreatitis is a common occurrence. Endoscopic ultrasound (EUS)-guided transmural drainage has become the treatment of choice for symptomatic pseudocysts. Following this procedure, stent migration can occur. A recently developed fully covered biliary metal stent with antimigration system has shown promise as an alternative endoprosthetic option for cystogastrostomy. The aim of this study is to describe the success and complications of using covered metal stents with antimigration system to drain pseudocysts at a single tertiary care center. Materials and Methods: The patients undergoing cystogastrostomy using the biliary metal stent with antimigration system over the course of a 10-month period (January-November, 2014) were retrospectively reviewed and all the pertinent information including length of the follow-up, age and sex of the patient, pseudocyst size, pseudocyst size at follow-up, and symptom improvement were recorded. Results: Five patients underwent endoscopic cystogastrostomy using a biliary metal stent with antimigration system. The average age of the patients was 57 years, with all the patients being males. The average size of the largest dimension of pseudocyst was 9 cm. The average follow-up time to repeat imaging was 30 days. All the patients had a significant improvement in their pseudocyst size, with two patients having complete resolution, one patient with a residual 2 cm cyst, and another with a residual 5 cm pseudocyst at follow-up. The average size at follow-up was 2 cm. No complications occurred during the follow-up period. No episodes of stent migration occurred. All the patients had symptom improvement at follow-up. Conclusion: Using a novel biliary covered self-expandable metal stent with antimigration system with EUS guidance to drain pseudocysts appears to be a safe and effective procedure in certain settings. Our experience shows rapid cyst resolution with no complications and no stent migration. This stent gives the providers another option when performing cystogastrostomy.

Background. There has been a growing use of both capsule endoscopy (CE) and double balloon enteroscopy (DBE) to diagnose and treat patients with obscure gastrointestinal blood loss and suspected small bowel pathology. Aim. To compare and correlate sequential CE and DBE findings in a large series of patients at two tertiary level hospitals in Wisconsin. Methods. An IRB approved retrospective study of patients who underwent sequential CE and DBE, at two separate tertiary care academic centers from May 2007 to December 2011, was performed. Results. 116 patients were included in the study. The mean age ± SD was 66.6 ± 13.2 years. There were 56% males and 43.9% females. Measure of agreement between prior capsule and DBE findings was performed using kappa statistics, which gave kappa value of 0.396 with P<0.001. Also contingency coefficient was calculated and was found to be 0.732 (P<0.001). Conclusions. Our study showed good overall agreement between DBE and CE. Findings of angioectasia had maximum agreement of 69%.

Polysilicon memory switching is demonstrated in vertical n-i-p diodes with TiN contacts and with feature sizes of 150 nm. An increase of more than three orders of magnitude of the forward current at +2 V is achieved after the application of a +8 V programming pulse. A physical change in the polysilicon is confirmed by different wet-etch rates of unprogrammed and programmed diodes. By comparing the ideality factors of the TiN-contacted diodes before and after programming, it is shown that the programming pulse increases the degree of order in the polysilicon. The mechanism by which the programming pulse increases order is electrothermal heating of the Si. When the metal contact to the polysilicon is changed from TiN to TiSi2, memory switching is eliminated. The TiSi2 contact seeds the crystallization of more ordered polysilicon during device fabrication compared to crystallization with TiN contacts, as shown by transmission electron microscopy

Physical and electrical analyses were carried out on n-channel polycrystalline silicon thin-film transistors (nTFTs) with active regions as thin as approximately 6 nm. Such thin active regions extinguish the dominating effects of anomalous leakage and allow the conduction energy barrier height to be analyzed as a function of gate voltage in the femtoampere source/drain current regime. Grain size statistics were determined using plan view transmission electron microscopy. It is shown for the first time that in the absence of anomalous leakage, the barrier height does not decrease with decreasing gate voltage. In addition, the maximum measured barrier height is almost independent of active region thickness and grain size statistics. The source/drain current at low lateral field and high vertical field is also independent of channel length for all devices with length varied over an order of magnitude. These important discrepancies with existing TFT conduction theory are discussed within a physics-based model that addresses the effects of disorder-induced localized electron states in the bandgap. Besides describing existing data and well-known TFT behavioral trends, the model predicts a previously unknown relationship between threshold voltage variation, average threshold voltage and the number of grains in the channel. Analysis of data gathered from hundreds of devices of different dimensions across three different grain size distributions not only leads to agreement with the model but also to a remarkable universal behavior linking electrical and physical properties. This study shows the physics of polycrystalline silicon TFT conduction to be of the same form as amorphous and single crystal devices with the degree of disorder as the sliding scale between the two extremes.

A physical and chemical analysis of a machine model (MM) electrostatic discharge (ESD) failure in a silicon circuit was carried out. Focused ion beam (FIB) was used to make cross sections through the region of contact burnout. The resulting samples were analyzed using scanning electron microscopy (SEM) and two-dimensional (2-D) auger electron spectroscopic (AES) mapping. It is shown for the first time that both titanium (Ti) and tungsten (W) migrated throughout the melted silicon filament. Large pellets of the W plug were embedded in the bulk silicon but only on the cathode side of the junction. Mechanisms are discussed to explain these phenomena. These involve the melting of titanium disilicide (TiSi/sub 2/), dissolution of Ti and W in the molten silicon and the formation of W pellets through electromigration at temperatures below /spl sim/1800 K.

The development of a fully continuous process for the synthesis of solketal (4-hydroxymethyl-2,2-dimethyl-1,3-dioxolane) is described. The use of a heterogeneous catalyst, recycle of unreacted starting material, elimination of the need for an entraining solvent, and purification of the product in situ all afford improvements over existing processes. Data generated in model reactions is used to prove the applicability of the process to a counter-current distillation reactor design, and to compute the operating parameters of the reactor.

A high yielding and selective method for producing methyl 5-amino-2H-1-benzopyran-8-carboxylate derivatives via gold(I)-catalysed intramolecular alkyne hydroarylation has been developed.

A very highly diastereoselective semipinacol rearrangement of 2,3-epoxy alcohol mediated by tin-(IV) chloride at ambient temperatures is shown to be applicable to a wide variety of migrating groups including methyl, tert-butyl, cyclopropyl; vinyl, alkynyl, phenyl, and 2-furyl. A synthetically valuable feature is that a mixture of syn- and anti-epoxy alcohol affords only a single diastereoisomerically pure β-hydroxy ketone. Additional advantages of the reaction include the presence in the product of two adjacent stereocenters and the efficient creation of a new quaternary center, valuable features in the synthesis of a variety of natural products

2,3-epoxyalcohols are shown to undergo stereoselective reactions in the presence of tin tetrachloride. The resulting diols when treated with acid are converted into polycyclic aromatic hydrocarbons or polycyclic ketones.

The minimising of torsional strain and non-bonding interactions is proposed as the explanation of high diastereoselectivity observed in the epoxidation of cycloalkenyl alcohols, reported for twenty three examples. The resulting 2,3-epoxyalcohols are key intermediates in the synthesis of tricyclic 1,2-diols and β-hydroxy ketones.

2,3-epoxyalcohols are shown to undergo stereoselective reactions in the presence of tin tetrachloride. The resulting diols when treated with acid are converted into polycyclic aromatic hydrocarbons or polycyclic ketones.

A very highly diastereoselective semipinacol rearrangement of 2,3-epoxy alcohol mediated by tin-(IV) chloride at ambient temperatures is shown to be applicable to a wide variety of migrating groups including methyl, tert-butyl, cyclopropyl; vinyl, alkynyl, phenyl, and 2-furyl. A synthetically valuable feature is that a mixture of syn- and anti-epoxy alcohol affords only a single diastereoisomerically pure β-hydroxy ketone. Additional advantages of the reaction include the presence in the product of two adjacent stereocenters and the efficient creation of a new quaternary center, valuable features in the synthesis of a variety of natural products

The minimising of torsional strain and non-bonding interactions is proposed as the explanation of high diastereoselectivity observed in the epoxidation of cycloalkenyl alcohols, reported for twenty three examples. The resulting 2,3-epoxyalcohols are key intermediates in the synthesis of tricyclic 1,2-diols and β-hydroxy ketones.

Energy efficiency has become an important consideration within urban development. Both the architectural and planning professions are beginning to explore ways to increase the energy efficiency of new development and the existing urban landscape. It is necessary when trying to use energy efficiency as a major consideration in urban development to develop a systematic analytical and design system on which all proposals can be based. Because urban design deals with the overall design of an area and combines many aspects of the various disciplines engaged in urban development, incorporating energy efficiency as a major design consideration into the discipline would mean that awareness of energy efficiency would become a part of every stage of the development process. It is the purpose of this paper to explore potential methods allowing energy efficiency to become part of urban design.

Helicoverpa armigera collected from cotton growing areas of South Sulawesi, Indonesia in 1987 and early 1988 were resistant to cypermethrin. It is suggested that the 86-fold resistance to cis-cypermethrin in 1987 and the 65-fold resistance to cis/trans-cypermethrin in 1988 are consistent with this being a major cause of failure to control the insects in cotton in this area. The second laboratory generation showed a 20-fold resistance to fenvalerate. The larvae collected in 1988 additionally had a 203-fold resistance to DDT and a 5.6-fold resistance to endosulfan. The results are discussed in relation to the fact that this is a further region in which Helicoverpa armigera has developed resistance to a number of pyrethroids.

This study compared external insulin pump treatment using insulin lispro or insulin aspart with multiple daily injections (MDI; four or more injections per day) using insulin glargine and insulin lispro or insulin aspart. An electronic database was used to retrieve various parameters of glycemic control for 515 adult patients with type 1 diabetes. An insulin pump was used by 216 patients, and 299 patients were taking insulin glargine for at least 6 months. The mean age (approximately 33 years), duration of diabetes (approximately 16 years), and duration of treatment (approximately 12 months) were similar for both the pump and insulin glargine groups. The mean (+/-SEM) A1C values were significantly reduced in both groups from the baseline to the end of the study (7.7 +/- 0.1% to 7.5 +/- 0.1% for the pump group and 8.0 +/- 0.1% to 7.7 +/- 0.1% for the insulin glargine group, P0.001) with similar weight gain (P0.05) in both groups. The insulin glargine group significantly reduced basal insulin intake at follow-up. The premeal boluses were similar throughout the study for both groups. The subjects reporting severe hypoglycemic episodes were similar in the two groups; however, there were 12 cases of diabetic ketoacidosis reported in the pump group and none in the insulin glargine group. Patients with type 1 diabetes can achieve similar glycemic control using insulin glargine with premeal insulin lispro or by using an external infusion pump with insulin lispro or insulin aspart. However, costs and episodes of diabetic ketoacidosis are significantly higher for insulin pump users.

Summary Background Medical research produces large multivariable datasets that are difficult to visualise and interpret intuitively. We describe a novel growing cell structure (GCS) technique that compresses multidimensional datasets into twodimensional maps with colour overlays that can be visually interpreted. Methods The two-dimensional map is self-discovered from the training set by distribution of cases to different nodes according to similarity between the cases at each node. Nodes are added to the map until there is no further significant reduction in error. The Parzen window method is used to estimate the probability distribution of the training cases, and this probability is converted to posterior class probabilities by use of Bayes' theorem. Classification performance can be assessed by means of receiver operating characteristic (ROC) curves. Colour maps of the values of each input variable at each node are constructed, which illustrate the relation between each input variable and the overall distribution of cases in the network map. Findings From a dataset of 11 input variables from 692 fineneedle aspirate samples from breast lesions, a 32-node network produced an area under the ROC curve of 0·96, which was not significantly different from that for logistic regression (0·98, z=1·09, p>0·05). Colour maps of the input variables showed that some variables had discrete distributions over exclusively benign or malignant areas of the network, and were thus discriminant, whereas others, such as foamy macrophages, covered both benign and malignant regions. Interpretation This technique produces dimensional compression that allows multidimensional data to be displayed as two-dimensional colour images. This envisioning of information allows the highly developed visuospatial abilities of human observers to perceive subtle inter-relations in the dataset.

The technique described provides a comprehensive integrated tool for the visualisation, analysis and classification of multidimensional data that is simple and intuitive to use owing to its visual nature. As an integrated tool, it provides users with the maximum information, allowing them to see how the classification system works and which subgroups of data it is able to classify confidently and which it is not. Further, it allows the potential for users to specify arbitrary decision boundaries to discriminate between subgroups of the data of particular interest in a way that is not possible in general classification systems. The technique has been demonstrated by application to the diagnosis of breast cancer from FNAB (Fine Needle Aspirates of Breast tissue) data, where it proved highly successful both in terms of classification results and the detection of correlations between input variables and the desired classification. The promise of the technique has been further demonstrated by the reaction of experienced doctors who found the method to be both simple and intuitive to use and in some respects more useful than existing statistical techniques. (3 pages)