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Most authors recommend an antireflux operation at the time of laparoscopic paraesophageal hernia (PEH) repair. A fundoplication combats the potential postoperative reflux resulting from disruption of the hiatal anatomy and may minimize recurrence. The purpose of this study is to evaluate the differences in postoperative dysphagia, reflux symptoms, and hiatal hernia recurrence in patients with and without a fundoplication at the time of laparoscopic paraesophageal hernia repair. Patients undergoing laparoscopic PEH repair from July 2006 to June 2012 were identified. Open repairs and reoperative cases were excluded. Patient characteristics, operative details, complications, and postoperative outcomes were recorded. Over the six-year period, 152 laparoscopic PEH repairs were performed. Mean age was 65.8 years (range, 31 to 92) and average body mass index was 29.9 kg/m(2) (range, 18 to 52 kg/m(2)). Concomitant fundoplication was performed in 130 patients (86%), which was determined based on preoperative symptoms and esophageal motility. Mean operative times were similar with fundoplication (188 minutes) and without (184.5 minutes). At a mean follow-up of 13.9 months, there were 19 recurrences: 12.3 per cent (16 of 130) in the fundoplication group and 13.6 per cent (three of 22) in those without. Dysphagia lasting greater than six weeks was present in eight patients in the fundoplication group (6.2%) and in none in those without (P = 0.603). Eighteen percent of patients without a fundoplication reported postoperative reflux compared with 5.4 per cent of patients with a fundoplication (P = 0.055). In the laparoscopic repair of PEH, the addition of a fundoplication minimizes postoperative reflux symptoms without additional operative time. Neither dysphagia nor hiatal hernia recurrence is affected by the presence of a fundoplication.

Context. Small amplitude oscillations in prominences have been known about for a long time, and from a theoretical point of view, these oscillations have been interpreted in terms of standing or propagating linear magnetohydrodynamic (MHD) waves. In general, these oscillations were studied by producing small perturbations in a background equilibrium with stationary physical properties. Aims. Taking into account that prominences are dynamic plasma structures, the assumption of a stationary equilibrium is not realistic. Therefore, our main aim is to study the effects produced by a non-stationary background on slow MHD waves, which could be responsible for prominence oscillations. Methods. Assuming that the radiation term is proportional to temperature and constant external heating, we have derived an expression for the temporal variation of the background temperature, which depends on the imbalance between heating and cooling processes. Furthermore, radiative losses, together with parallel thermal conduction, have also been included as damping mechanisms for the waves. Results. As temperature increases with time, the period of slow waves decreases and the amplitude of the velocity perturbations is damped. The inclusion of radiative losses enhances the damping. As temperature decreases with time, the period of slow waves increases and the amplitude of velocity perturbations grows while, as expected, the inclusion of radiative losses contributes to the damping of oscillations. Conclusions. There is observational evidence that, in different locations of the same prominence, oscillations are damped or amplified with time. This temporal damping or amplification can be obtained by a proper combination of a variable background temperature, together with radiative damping. Furthermore, decayless oscillations can also be obtained with an appropriate choice of the characteristic radiation time.

The two most common techniques for laparoscopic inguinal hernia repair are the transabdominal preperitoneal (TAPP) technique and the totally extraperitoneal (TEP) technique. Although in the end both techniques are used to place mesh in the preperitoneal space to cover the entire myopectineal orifice, they differ in how access to that space is obtained, and slight differences between the two approaches exist. TAPP is quicker to learn and is associated with an overall low but higher risk of visceral injury and port-site herniation. TAPP has a slight operative time advantage with no difference in hernia recurrence rate. Pain may be more a function of mesh fixation during the operation rather than technique itself. This chapter discusses the risks and benefits of each technique and compares their surgical outcomes.

Hand-assisted laparoscopic surgery (HALS) bridges traditional open surgery and pure laparoscopy. The HALS technique provides the necessary site for organ retrieval, reduces operative time, and realizes the postoperative benefits of laparoscopic techniques. Although the reported rates of incisional hernia should be theoretically low, we sought to determine our incidence of hernia after HALS procedures. A retrospective review of all HALS procedures was performed from July 2006 to June 2011. All patients who developed postoperative incisional hernias at the hand port site were confirmed by imaging or examination findings. Patient factors were reviewed to determine any predictors of hernia formation. Over the 5 years, 405 patients undergoing HALS procedures were evaluated: colectomy (264), nephrectomy (107), splenectomy/pancreatectomy (18), and ostomy reversal (10). The overall incidence of incisional hernia was 10.6 per cent. There were three perioperative wound dehiscences. The mean body mass index was significantly higher in the hernia group versus the no hernia cohort (32.1 vs 29.2 kg/m(2); P = 0.001). The hernia group also had a higher incidence of renal disease (18.6 vs 7.2%; P = 0.018). Mean time to hernia formation was 11.4 months (range, 1 to 57 months). Follow-up was greater than 12 months in 188 (46%) of patients, in which the rate of incisional hernia was 17 per cent. The rate of incisional hernia formation after hand-assisted laparoscopic procedures is higher than the reported literature. Because the mean time to hernia development is approximately 1 year, it is important to follow these patients to this end point to determine the true incidence of incisional hernia after hand-assisted laparoscopy.

Although the safety of bariatric surgery in patients with established cardiovascular disease has been demonstrated, little is known about the mid- to long-term survival of these patients after surgery. We conducted a retrospective cohort study of bariatric surgical patients (n = 349) compared with morbidly obese surgical controls (n = 903). Data were obtained on all patients 40 to 79 years of age, from 1996 to 2008, with a diagnosis code of morbid obesity, a primary surgical procedure of interest, and a cardiovascular event history. Data sources were the statewide South Carolina UB92 inpatient hospitalization database and death records. The primary outcome was all-cause mortality. A total of 349 bariatric and 903 control patients with cardiovascular event histories were identified. Among bariatric patients, 19 deaths occurred in 986 person-years of follow-up versus 150 deaths among controls in 3138 person-years of follow-up. Unadjusted all-cause mortality was estimated at 7 ± 2 per cent at 5 years in bariatric patients compared with 19 ± 2 per cent (P0.001) in controls. Adjusting for age, comorbidities, and event history, the relative risk of mortality was reduced by 40 per cent in bariatric patients compared with controls [hazard ratios (95% confidence interval): 0.60 (0.36, 0.99)]. In patients with a history of cardiovascular events, bariatric surgery is associated with a significantly decreased risk of all-cause mortality.

Participants were asked to categorize a series of syllables varying from /ga/ to /da/ presented in isolation or following /al/, /ar/, /a/, or filtered noise bands. Typical shifts in categorization were obtained for /al/ vs. /ar/ contexts as predicted by compensation for coarticulation, but the shift in response between isolated presentation and any of the context conditions was much larger, even when the context was broadband noise. These results suggest that the effect of the presence of any context sound is greater than the effect of the content of the context sounds.

Alfven wave dynamics in partially ionized plasmas of the solar atmosphere shows that there is indeed a cut-off wavenumber, i.e. the Alfven waves with wavenumbers higher than the cut-off value are evanescent. The cut-off wavenumber appears in single-fluid magnetohydrodynamic (MHD) approximation but it is absent in a multi-fluid approach. Up to now, an explanation for the existence of the cut-off wavenumber is still missing. The aim of this paper is to point out the reason for the appearance of a cut-off wavenumber in single-fluid MHD. Beginning with three-fluid equations (with electrons, protons and neutral hydrogen atoms), we performed consecutive approximations until we obtained the usual single-fluid description is obtained. We solved the dispersion relation of linear Alfven waves at each step and sought the approximation responsible of the cut-off wavenumber appearance. We have found that neglecting inertial terms significantly reduces the real part of the Alfven frequency although it never becomes zero. Therefore, the cut-off wavenumber does not exist at this stage. However, when the inertial terms together with the Hall term in the induction equation are neglected, the real part of the Alfven frequency becomes zero. The appearance of a cut-off wavenumber, when Alfven waves in partially ionized regions of the solar atmosphere are studied, is the result of neglecting inertial and Hall terms, therefore it has no physical origin., Comment: 6 pages, 2 figures, accepted in A&A

The most common indications for gastric resection remain benign ulcer disease and neoplasm. Surgery for these diseases can be performed safely with laparoscopy. As surgeons adhere to the original tenets of open gastric resections while performing laparoscopic resections, disease outcomes will remain the same with the improved surgical outcomes of less pain, a shorter hospital stay, and a lower incidence of wound complications. Laparoscopic gastric resections can be divided into the more straightforward wedge/tumor resections performed for submucosal tumors or the more formal anatomic gastric resections. This article reviews the tools and techniques for laparoscopic gastric resection.

Rapidly rotating stars show short-period oscillations in magnetic activity and polar appearance of starspots. The aim of this paper is to study large-scale shallow water waves in the tachoclines of rapidly rotating stars and their connection to the periodicity and the formation of starspots at high latitudes. Shallow-water magnetohydrodynamic equations were used to study the dynamics of large-scale waves at the rapidly rotating stellar tachoclines in the presence of toroidal magnetic field. Dispersion relations and latitudinal distribution of wave modes were derived. We found that low-frequency magnetic Rossby waves tend to be located at poles, but high-frequency magnetic Poincare waves are concentrated near the equator in rapidly rotating stars. These results have important implications for the evolution of the stellar wind in young Sun-like stars. Unstable magnetic Rossby waves may lead to the local enhancement of magnetic flux at high latitudes of tachoclines in rapidly rotating stars. The enhanced magnetic flux may rise upwards owing to the magnetic buoyancy in the form of tubes and appear as starspots at polar regions. Magnetic Rossby waves may also cause observed short-term periodicity in the stellar magnetic activity., 12 pages, 7 figures, A&A (accepted)

Background Anastomotic stricture remains the most common complication after laparoscopic gastric bypass with a circular-stapled gastrojejunostomy. The present study examined the effect of the use of bioabsorbable circular staple line reinforcement on the incidence of gastrojejunostomy anastomotic strictures as a complication of laparoscopic Roux-en-Y gastric bypass. Methods A retrospective review was performed of 851 consecutive patients who underwent laparoscopic Roux-en-Y gastric bypass with circular-stapled gastrojejunostomy. Gore SeamGuard bioabsorbable circular staple line reinforcement was used in 596 consecutive patients subsequent to 255 consecutive patients without anastomotic reinforcement. The incidence of anastomotic stricture was compared after mean follow-up periods of 19 and 22 months for the two groups. Results Anastomotic stricture requiring intervention was identified in 28 patients (2.94%). Only four patients (.67%) in the SeamGuard group developed anastomotic stricture compared with 24 patients (9.41%) in the no SeamGuard group. The use of staple line reinforcement is consistent with a 94% risk reduction in stricture formation. Conclusion The results have shown that the use of bioabsorbable circular staple line reinforcement on gastrojejunal anastomoses in laparoscopic Roux-en-Y gastric bypass significantly reduces the incidence of anastomotic stricture. The standard use of the bioabsorbable reinforcement on circular staple line anastomoses could be a part of the solution to the most common complication of laparoscopic gastric bypass.

Solar prominences are partially ionised plasmas displaying flows and oscillations. These oscillations show time and spatial damping and, commonly, have been explained in terms of magnetohydrodynamic (MHD) waves. We study the spatial damping of linear non-adiabatic MHD waves in a flowing partially ionised plasma, having prominence-like physical properties. We consider single fluid equations for a partially ionised hydrogen plasma including in the energy equation optically thin radiation, thermal conduction by electrons and neutrals, and heating. Keeping the frequency real and fixed, we have solved the obtained dispersion relations for the complex wavenumber, k, and have analysed the behaviour of the damping length, wavelength and the ratio of the damping length to the wavelength, versus period, for Alfven, fast, slow and thermal waves., 28 pages, 9 figures

Quasi-biennial oscillations (QBO) are frequently observed in the solar activity indices. However, no clear physical mechanism for the observed variations has been suggested so far. Here we study the stability of magnetic Rossby waves in the solar tachocline using the shallow water magnetohydrodynamic approximation. Our analysis shows that the combination of typical differential rotation and a toroidal magnetic field with a strength > 10^5 G triggers the instability of the m=1 magnetic Rossby wave harmonic with a period of 2 years. This harmonic is antisymmetric with respect to the equator and its period (and growth rate) depends on the differential rotation parameters and the magnetic field strength. The oscillations may cause a periodic magnetic flux emergence at the solar surface and consequently may lead to the observed QBO in the solar activity features. The period of QBO may change throughout the cycle, and from cycle to cycle, due to variations of the mean magnetic field and differential rotation in the tachocline., 13 pages, 4 figures, ApJ (in press)

In this paper dual representable aggregation functions (DRAF's) are introduced and studied. After giving a representation theorem for them, it is proved that they can be viewed as a nonassociative generalization of nilpotent t-conorms, some basic properties are proved and some examples are given. On the other hand, using DRAF's a new kind of strong implications are derived and some usual properties are studied for this new class of implications. In particular, it is shown that they have an easy structure always divided into three parts depending on the strong negation.

The presence of intermediate-term periodicities in solar activity, at approximately 323 and 540 days, has been claimed by different authors. In this paper, we have performed a search for them in the historical records of two main indices of solar activity, namely, the daily sunspot areas (cycles 12–21) and the daily Zurich sunspot number (cycles 6–21). Two different methods to compute power spectra have been used, one of them being especially appropriate to deal with gapped time series. The results obtained for the periodicity near 323 days indicate that it has only been present in cycle 21, while in previous cycles no significant evidence for it has been found. On the other hand, a significant periodicity at 350 days is found in sunspot areas and Zurich sunspot number during cycles 12–21 considered all together, also having been detected in some individual cycles. However, this last periodicity must be looked into with care due to the lack of confirmation for it coming from other features of solar activity. The periodicity around 540 days is found in cycles 12, 14, and 17 in sunspot areas, while during cycles 18 and 19 it is present, with a very high significance, in sunspot areas and Zurich sunspot number. It also appears at 528 days in sunspot areas during cycles 12–21. On the other hand, it is important to note the coincidence between the asymmetry, favouring the northern hemisphere, of sunspot areas and solar flares during cycle 19, and the fact that the periodicity at 540 days was only present, with high significance, in that hemisphere during that solar cycle.

Although surgeons can safely perform endoscopic retrograde cholangiopancreatography (ERCP), it has fallen within the domain of gastroenterologists. We sought to quantify the role of ERCP in a tertiary-care surgery department. The hospital discharge database was queried for all ERCPs performed from January 2007 to December 2007. Gastroenterologists performed all ERCPs in our query. Surgical patients were admitted and/or under the care of a surgeon; whereas nonsurgical patients had no surgeon involvement. Patient characteristics and diagnoses were compared between groups. ERCP procedural details were recorded. Surgical patients comprised 48 per cent (n = 151) of the total 311 ERCPs performed. The mean time interval from a surgeon's request for ERCP to actual procedure was 2.43 days (standard deviation [SD] 2.55; range, 0-13 days). The surgical group had significantly different diagnoses and underwent less diagnostic (22% vs 56%) and more therapeutic ERCPs (72% vs 38%). Surgical patients were more likely inpatients (82.1% vs 16.8%) with a longer length of stay (6.7 vs 3.9 days; P = 0.0029) compared with nonsurgical patients. We found surgical patients requiring ERCP differ significantly from nonsurgical patients, with a significant number of technical interventions being outsourced. Given the benefits of a surgical ERCP program and the potential volume of these unique patients, this procedure should be performed by appropriately trained surgeons.

Mesh contamination is the most feared postoperative complication after ventral herniorrhaphy. The morbidity is significant requiring additional operative procedures for debridement or complete removal of the prosthesis. From July 1998 to December 2007, a retrospective review was performed to evaluate the incidence of mesh infection in patients undergoing an elective, open intra-abdominal sublay technique of repair using a composite mesh of polypropylene and expanded polytetrafluoroethylene (Composix, Davol, Inc., Cranston, RI). There were 206 procedures involving open, intraperitoneal placement of Composix mesh resulting in 21 mesh infections (10.2%). The majority of infections were secondary to Staphylococcus aureus contamination (76%), and over half were infected with MRSA. All patients, except two, required mesh removal. Reoperation for repair of the recurrent defect after mesh removal was necessary in 67 per cent. Two patients with MRSA infection subsequently reinfected their recurrent repair. Overall, the infected group required 44 additional procedures (mean of 2.1 procedures/patient). The infection risk was reduced with the lighter density, newer generation composite mesh (7.3% vs 14.5%). Mesh infection after ventral herniorrhaphy conveys significant morbidity. An open intraabdominal underlay of a composite mesh of polypropylene and ePTFE carries a real risk of contamination and should be reconsidered.

Acting as a pneumatic tissue expander, progressive preoperative pneumoperitoneum (PPP) pressurizes the abdomen to prepare patients with giant hernias and loss of domain for hernia repair. We review our experience with PPP. Between 2006 and 2008, a prospective hernia database revealed nine patients who underwent PPP prior to hernia repair. Mean patient age was 54 years (41-68) and mean BMI was 31.3 kg/m2 (25.2-36.5). Patients had prophylactic vena cava filters and intraperitoneal catheters placed. Over a mean 22.4 days (7-64), patients received 7.6 (3-13) injections of air. PPP complications included death from pulmonary mycetoma (1), deep venous thrombosis and acute renal failure (1), port infection (1), kinked catheter requiring reoperation (1). Seven patients underwent successful hernia repair; open ventral (6) and laparoscopic inguinal (1). Defect size averaged 387 cm2 (110-980) with a mesh size of 420 cm (180-1200). Operative time averaged 256 minutes (175-330) with a mean blood loss of 157 ml (50-500). Post-hernia repair length of stay was 10.3 days (4-22). Hernia repair complications included ventricular tachycardia (1) and hernia recurrence (1). PPP has an acceptable risk, and for patients with large hernias and loss of domain, it may be a useful adjunct prior to definitive hernia repair.

Obesity has become an increasing problem in developed countries and laparoscopic Roux-en-Y gastric bypass (LRYGB) is one of the leading treatments for this disease. Although studies show that it is effective in reducing weight and lessening comorbidities, both early and late complications can occur. Early complications include venous thromboembolism, anastomotic leak, and hemorrhage. Late complications include obstruction, anastomotic stenosis, fistula, ulcer, cholelithiasis and nutritional deficiencies. Diagnosis of these complications is often challenging due to the lack of specificity of the presenting signs and symptoms. A high index of suspicion for detecting these complications is universally advocated. Fortunately, mortality from this procedure is rare. Management of the complications is generally consistent with basic surgical principles and surgical reinterventions can often be performed either endoscopically or laparoscopically depending on the situation and the surgeon's expertise. The available literature is confounded by mixing of results between open and laparoscopic techniques as well as the substantial differences in technique between authors reporting their outcomes. Although there is no consensus for managing the reported complications of LRYGB surgery, this article reviews the current literature and describes the presentation, diagnosis, and management of each of the early and late complications associated with the procedure.

Apart from the 11-year solar cycle, another periodicity around 155-160 days was discovered during solar cycle 21 in high energy solar flares, and its presence in sunspot areas and strong magnetic flux has been also reported. This periodicity has an elusive and enigmatic character, since it usually appears only near the maxima of solar cycles, and seems to be related with a periodic emergence of strong magnetic flux at the solar surface. Therefore, it is probably connected with the tachocline, a thin layer located near the base of the solar convection zone, where strong dynamo magnetic field is stored. We study the dynamics of Rossby waves in the tachocline in the presence of a toroidal magnetic field and latitudinal differential rotation. Our analysis shows that the magnetic Rossby waves are generally unstable and that the growth rates are sensitive to the magnetic field strength and to the latitudinal differential rotation parameters. Variation of the differential rotation and the magnetic field strength throughout the solar cycle enhance the growth rate of a particular harmonic in the upper part of the tachocline around the maximum of the solar cycle. This harmonic is symmetric with respect to the equator and has a period of 155-160 days. A rapid increase of the wave amplitude could give place to a magnetic flux emergence leading to observed periodicities in solar activity indicators related with magnetic flux., Comment: 34 pages, 5 figures, accepted in ApJ

The environmental problems of the Lake Valencia Basin are described. A multipurpose project for the treatment and reuse of 9.5 m3/s of wastewater, which has received approval for international funding, is discussed along with technological adaptations to local opportunities and limitations. The results of bench-scale studies for potable reuse of the Lake's water by softening and blending are also described along with experience of surrogate parameters for Trihalomethane Formation Potential Measurement in a Developing world context.

With the increased use of CT, discovering incidental pancreatic lesions has become commonplace. Lesions in the distal pancreas lend themselves well to laparoscopic resection. We reviewed our experience with laparoscopic distal pancreatectomy. During the study period, 32 distal pancreatectomies were performed. There were 20 females. Mean patient age was 58.0 years (range, 23-83 years) and mean body mass index was 29.9 Kg/m2 (range, 19.9-44.7 Kg/m2). Technique was laparoscopic (25) or hand-assisted (seven) with one conversion in each group. The spleen was preserved in six patients (18.8%). Mean operative time overall was 238 minutes (range, 140-515 minutes); hand-assisted was 222 minutes and laparoscopic was 254 minutes. Estimated blood loss averaged 221 mL (range, 50-1800 mL). Mean tumor size was 2.7 cm (range, 0.6-7 cm). Tumor pathology was serous cystadenoma (10), neuroendocrine tumor (six), mucinous cystic neoplasm (four), intrapapillary mucinous neoplasm (four), adenocarcinoma (three), other (four), and solid pseudopapillary neoplasm (one). Mean length of stay was 5 days (range, 3-11 days). Complications were pancreatic fistula (six), wound infection (two), pulmonary embolism (one), pancreatitis (one), myocardial infarction (one), postoperative bleed from combined laparoscopic bilateral oophorectomy (one), and pancreatic stump staple line bleed requiring reoperation (one). There were no perioperative deaths. All pancreatic fistulas resolved with conservative management.

We present a thorough study of the North-South asymmetry of solar activity made with the daily sunspot areas since they are good indicators of magnetic activity. To perform the study, we have constructed an asymmetry time series and analyzed it by different methods. First of all, its significance and statistical behaviour have been studied. Secondly, using a Monte Carlo simulation we have generated synthetic asymmetries and compared them to the real one and, thirdly, we have used modern techniques, developed to study the chaotic behaviour of time series, to search for low-dimensional chaos in the asymmetry time series. Our results show that in most cases the north-south asymmetry is statistically highly significant and that it cannot be obtained from a distribution of sunspots areas generated, in a random way, from a binomial or uniform distribution of probability between hemispheres. Moreover, the real asymmetry time series can be represented by a means of a multi-component model made up of a long term trend, a sinusoidal component with a period of 12.1 yr and a dominant purely random component; while chaotic analysis does not reveal the existence of a strange attractor in the time series.

OBJECTIVE--To determine the extent of transmission of hepatitis C virus in sexual partners of intravenous drug misusers and to examine the relation between the prevalences of HIV, hepatitis B virus, and hepatitis C virus infections in homosexual men and intravenous drug misusers and their sexual partners. DESIGN--Serum samples collected between 1984 and 1988 were tested for hepatitis B virus markers and antibodies against hepatitis C virus by enzyme linked immunosorbent assay (ELISA) and for HIV antibody by enzyme immune analysis and western blotting. SETTING--Large referral university hospital with an external AIDS clinic in the metropolitan area of Barcelona, Spain. SUBJECTS--243 Intravenous drug misusers, 143 of their regular heterosexual partners, and 105 homosexual men. MAIN OUTCOME MEASURES--Prevalences of hepatitis C virus, hepatitis B virus, and HIV infections. RESULTS--In all, 178 of the 243 (73%) intravenous drug misusers, 16 out of 143 (11%) of their partners, and 17 of the 105 (16%) homosexual men had antibodies against hepatitis C virus. The presence of hepatitis C virus infection was unrelated to sex, age, the presence of HIV or hepatitis B virus infections, or the Centers for Disease Control stage of HIV. In sexual partners of intravenous drug misusers there were strong correlations between the presence of hepatitis C virus infection and that of HIV (p = 0.001) and hepatitis B virus (p = 0.013) infections. CONCLUSIONS--Intravenous drug misusers have a high risk of acquiring hepatitis C virus, hepatitis B virus, and HIV infections, but the presence of hepatitis C virus infection seems to be unrelated to the presence of the other two viruses. Homosexual men have a high prevalence of HIV and hepatitis B virus infections with a low prevalence of hepatitis C virus infection, the presence of which is not related to that of the other two infections. Conversely, heterosexual partners of intravenous drug misusers have low prevalences of the three virus infections, but the presence of hepatitis C virus infection correlates significantly with the presence of HIV and hepatitis B infections. The rate of sexual transmission of hepatitis C virus seems to be low, even in partners of people known to be seropositive for this virus.

The retromuscular or sublay repair of ventral hernias, popularized by Rives and Stoppa, requires that a layer of tissue be reapproximated dorsal to the mesh to separate the bowel from the prosthetic. This is the first report of two patients who developed bowel obstruction resulting from interparietal incarceration between the posterior rectus sheath and the prosthetic graft through a defect in this dorsal layer. Both patients underwent open retromuscular hernia repair, one with lightweight polypropylene mesh, the other with human acellular dermal matrix. Postoperatively (day 3 and day 42, respectively), the patients developed signs of bowel obstruction. Computed tomography demonstrated the herniation of the small bowel into the potential space between the prosthesis and the posterior rectus sheath. The first patient underwent successful laparoscopic repair, while the second patient had an open operation to reduce the incarcerated bowel and repair the defect. In the patient convalescing from an uneventful retromuscular hernia repair who develops signs and symptoms of a bowel obstruction, there should be a high index of suspicion that an interparietal hernia may have formed, with the small bowel herniated into the surgically created space between the prosthetic and the posterior rectus sheath.

In ubiquitous computing, the main security challenges arise from network heterogeneity and from a dynamic population of nomadic users and limited devices. For these environments, security infrastructures based on traditional PKIs present a number of major drawbacks: limited scalability and reconfigurability, static vision of trust, and high administrative costs. Besides, these infrastructures are not well adapted to authorisation, and lack delegation capabilities. In this paper, we present an enhanced PKI for ubiquitous networks which solves a number of these issues by providing flexible authentication and authorisation services in disconnected environments

The Angelchik prosthesis is a silicone gel-filled implant historically placed around the gastroesophageal junction for the treatment of gastroesophageal reflux disease. Herein, we describe the laparoscopic transgastric removal of an Angelchik prosthesis that had eroded through the gastroesophageal junction of a patient 25 years after its placement. Under direct laparoscopic and endoscopic guidance, laparoscopic trocars were placed transabdominally, directly into the gastric lumen. Using 2-mm instrumentation, the prosthesis was transected, endoscopically snared, and removed perorally. The patient was discharged after a 3-day hospital stay. This is the first published description of a laparoscopic, transgastric approach to removal of a partially eroded prosthetic device to the stomach.

The purpose of this study was to measure the extent of adhesion formation to ePTFE mesh (DualMesh, W.L. GoreAssociates, Inc, Flagstaff, AZ) and two composite prosthetic materials, ePTFE and polypropylene (Bard Composix, C.R. Bard, Inc, Murray Hill, NJ) and hyaluronic acid/carboxymethylcellulose and polypropylene (Sepramesh, Genzyme Corp, Cambridge, MA) after their intra-abdominal placement on an intact peritoneum, simulating laparoscopic ventral hernia repair, and to evaluate host tissue response to the prosthetic biomaterials.Through a midline laparotomy, a 2 x 2 cm piece of mesh (n = 60) was sewn to an intact peritoneum on each side of a midline incision in 30 New Zealand white rabbits. Mesh adhesions were scored using a modified Diamond scale (0 = 0%, 1 = 1-25%, 2 = 26-50%, 350%) at 1, 3, 9, and 16 weeks by serial microlaparoscopy (2 mm). All laparoscopic evaluations were videotaped for blinded scoring by three surgeons. Host tissue response was graded (1-4) for inflammation, tissue ingrowth, and mesothelialization. The predominant cell type (polymorphonuclear leukocytes versus foreign body giant cell) was recorded. Statistical differences (P value0.05*) were measured using a two-tailed t test and Kruskal-Wallis test.The mean adhesion score was significantly (P0.001) less for ePTFE mesh at 1, 3, 9, and 16 weeks compared with the two composite prosthetic materials. There were no differences in the mean adhesion scores between the two biosurgical composite meshes at any of the time intervals. There were no differences in the mean score for inflammation, tissue ingrowth and mesothelialization between any of the prosthetic biomaterials. The predominant cell type on all histological evaluations was polymorphonuclear leukocytes.Placing ePTFE mesh (DualMesh) intra-abdominal against an intact peritoneum results in significantly fewer adhesions than the composite prosthetic meshes during a 4-month follow-up. The host tissue response is equivalent for the three prosthetic biomaterials. The long-term consequences of increased adhesion formation to the composite meshes and the ultimate biocompatibility of the nonabsorbable and absorbable barriers on the polypropylene mesh are to be determined.

Cirrhosis of the liver contributes significantly to morbidity and mortality in abdominal surgery. The proven benefits of laparoscopy seem especially applicable to patients with this complex disease. This study evaluates the safety and efficacy of laparoscopic procedures in a series of consecutively treated patients with biopsy-proven cirrhosis. The medical records of all patients with biopsy-proven cirrhosis undergoing laparoscopic surgery at the authors’ medical center between January 2000 and December 2003 were retrospectively reviewed. A total of 50 patients (27 men and 23 women) underwent 52 laparoscopic procedures. Among these 50 patients were 39 patients with Child-Pugh classification A cirrhosis, 10 with classification B, and 1 with classification C, who underwent a variety of laparoscopic procedures including cholecystectomy (n = 22), splenectomy (n = 18), colectomy (n = 4), diagnostic laparoscopy (n = 3), ventral hernia repair (n = 1), Nissen fundoplication (n = 1), Heller myotomy (n = 1), Roux-en-Y gastric bypass (n = 1), and radical nephrectomy (n = 1). There were two conversions (4%) to an open procedure. The mean operative time was 155 min. Estimated blood loss averaged 124 ml for all procedures, and 20 patients (40%) required perioperative transfusion of blood products. One patient required a single blood transfusion postoperatively because of anemia. No one experienced hepatic decompensation. Overall morbidity was 16%. There were no deaths. The mean length of hospitalization was 3 days. Although technically challenging because portal hypertension, varices, and thrombocytopenia frequently coexist, basic and advanced laparoscopic procedures are safe for patients with mild to moderate cirrhosis of the liver.

Despite the use of a sterile technique and the administration of prophylactic antibiotics during surgical procedures, mesh infection continues to complicate the use of biomaterials. The purpose of this study was to compare the susceptibility to infection of prosthetic biomaterials in a live-animal model. The following seven prosthetic mesh biomaterials were used in this study. Expanded polytetrafluoroethylene (ePTFE) with silver/chlorhexidine (DM+), ePTFE (DM), porcine intestinal submucosa (S), polypropylene (M), ePTFE/polypropylene (X), hyaluronate/carboxymethylcellulose/polypropylene (SM), and human acellular dermal matrix (A). Lewis rats (n = 108) underwent creation of a single ventral hernia; 105 of them were repaired with a different mesh (2-cm2 piece). Twelve pieces of each mesh were inoculated at the time of hernia repair with 108 Staphylococcus aureus (n = 84). Three pieces of each mesh were placed without bacterial inoculation (n = 21). In three animals, no mesh was placed; instead, the peritoneum of the hernia defect was inoculated (n = 3). After 5 days, the animals were killed and the mesh was explanted (peritoneum for the nonmesh control). The mesh was vortex-washed and incubated in tryptic soy broth. Bacterial counts were determined using serial dilutions and spot plates and quantified in colony-forming units (CFU) per square centimeter of mesh present in the vortex wash fluid (wash count) and the soy broth (broth count). Data are presented as the mean log10, with analysis of variance (ANOVA) and Tukey’s test used to determine significance (p < 0.05). The DM+ material had no detectable live bacteria in the wash or broth counts in 10 of 12 tested samples (p = 0.05). Of the samples that showed bacterial growth, the peritoneum control group had a lower wash count than A (p = 0.05) and the lowest broth count of all the materials except for DM+ (p = 0.05). In addition, SM had a significantly lower wash count than A (p = 0.05), with no broth count difference. In regard to wash and broth counts, DM, M, X, SM, S, and A were no different (p = NS). The DM+ material was the least susceptible to infection. Impregnation with silver/chlorhexidine killed the inoculated bacteria, preventing their proliferation on the mesh surface. Other than DM+, native peritoneal tissue appears to be the least susceptible to infection. Silver/chlorhexidine appears to be an effective bactericidal agent for use with mesh biomaterials.

Pegylated-interferon (IFN) plus ribavirin remains the most effective therapeutic regimen for patients with chronic hepatitis C infection. Thrombocytopenia is a common side effect of this treatment, often leading to discontinuation of a potentially curative therapy. We sought to determine the safety and efficacy of laparoscopic splenectomy in correcting thrombocytopenia, thus allowing completion of IFN therapy. Data were collected prospectively from September 2000 to May 2003 on all patients undergoing laparoscopic splenectomy for thrombocytopenia associated with IFN therapy and/or hepatitis C cirrhosis with portal hypertension. Demographic data, model of end-stage liver disease (MELD) score, platelet count, operative time, blood loss, spleen weight, complications, length of stay, and follow-up time were calculated. Eleven patients (7 men, 4 women) underwent laparoscopic splenectomy; their mean age was 45.4 years (range 27 to 55 years) and mean body mass index was 27 kg/m(2) (range 21 to 44 kg/m(2)). All patients were Child's class A, with a mean preoperative MELD score of 9.1 (range 6 to 11). Mean operative time was 189 minutes (range 70 to 245 minutes), and blood loss averaged 141 ml (range 10 to 600 ml). A hand-assisted laparoscopic technique was used in four cases. Six patients received empiric intraoperative platelet administration. None required transfusion with packed red cells. Splenic weight averaged 1043 g (range 245 to 1650 g). Average length of stay was 2.6 days (range 1 to 6 days). Four patients had the following minor postoperative complications: self-limited atrial fibrillation (n=1), trocar site cellulitis (n=1), and atelectasis (n=2). There have been no major complications over an average follow-up of 11 months (range 1 to 18 months). Mean postoperative MELD score was 8.3 (range 6 to 10). Platelet counts improved from a preoperative mean of 55000/ul (16000 to 88000/microl) to 439000/microl (200000 to 710000/microl) postoperatively and have remained above 100000/microl (104000 to 397000/microl) during subsequent pegylated-IFN therapy. Three patients have completed a full course of IFN therapy and have obtained a sustained virologic response. Treatment is ongoing in the remaining patients. Laparoscopic splenectomy is safe in the setting of portal hypertension and thrombocytopenia associated with chronic hepatitis C infection. It can be performed with little blood loss, no need for red cell transfusion, and minimal perioperative morbidity. Laparoscopic splenectomy appears to effectively reverse thrombocytopenia and may allow these patients to safely complete IFN therapy.

The development of new energy sources for hemostasis has facilitated advanced laparoscopic procedures. Few studies, however, have documented the strength of the vessels sealed or the extent of surrounding lateral thermal injury, two important factors in maintaining hemostasis while preventing injury to surrounding structures. This study compared the burst pressure and extent of thermal injury of vessels sealed with the 5-mm laparoscopic PlasmaKinetics trade mark sealer (PK) (Gyrus Medical, Maple Grove, Minnesota) and the 5-mm laparoscopic LigaSure trade mark sealing device (LS) (Valleylab, Boulder, Colorado).Arteries in three sizes (2-3 mm, 4-5 mm, and 6-7 mm) were harvested from domestic pigs. Eight to 17 specimens from each size were randomly sealed with the PK, and the same number with the LS. Burst pressures were measured in mm Hg. The extent of thermal injury, determined by coagulation necrosis, was measured microscopically in millimeters after staining the transected vessels with hematoxylin and eosin. Descriptive statistics, including means and standard deviations, are reported. Student's t-test and ANOVA were performed to determine significance (P.05).The mean bursting pressures of the PK and the LS were equal in the 2-3 mm vessels (397 vs. 326 mm Hg, P =.49). The PK bursting pressures were significantly less than the LS in the 4-5 mm (389 vs. 573 mm Hg, P =.02) and the 6-7 mm groups (317 vs. 585 mm Hg, P =.0004). As vessel size increased, the PK was associated with significantly lower burst pressures, while the LS was associated with progressively higher burst pressures (P =.035). Thermal spread was not significantly different between the PK and the LS in the 2-3 mm (1.5 vs. 1.2 mm, P =.27), the 4-5 mm (2.4 vs. 2.4 mm, P =.79), or the 6-7 mm vessel size groups (3.2 vs. 2.5 mm, P =.32). Increasing vessel size, regardless of instrument used, was associated with increased thermal injury (P.0001).The LS produces supraphysiologic seals with significantly higher bursting pressures than the PK in vessels ranging from 4 to 7 mm. The PK seals become progressively weaker while the LS seals increase in strength as the vessel size increases. Although thermal spread increases with vessel size, the degree of lateral thermal injury is no different between the two instruments.

We report a case of de novo partial duplication of the distal segment of the long arm of chromosome 5 (q31--qter). The patient showed dysmorphic features (flat face, short and horizontal palpebral fissures, depressed and broad nasal bridge, wide nose with hypoplastic alae nasae, short and flat philtrum, high arched palate, micrognathia, anomalies of the ears), redundant adipose panniculus of the neck, proximal shortening of the limbs, flexion contractures, long and distally widened fingers, bilateral clubfoot, single umbilical artery, hypoplasia of lung and pulmonary arteries, atrial septal defect and patent ductus arteriosus. She died 23 hours after birth from respiratory failure. Chromosome analysis with high resolution GTG bands showed 46,XX,1p1, which was interpreted as a partial duplication of the distal long arm of chromosome 5 (q31--qter). Fluorescence in situ hybridization analyses with whole chromosome painting technique for chromosome 5 proved that this extra region belonged to chromosome 5. Our case is the first to have a de novo partial duplication of this chromosome segment.

Advanced laparoscopy in the morbidly obese patient is technically challenging. Having the proper instrumentation and equipment available is a major component of technical success. Items routinely used during surgery performed on patients of normal size must often be modified or substituted when morbidly obese patients undergo surgery. In this article, we review the specific tools necessary for the safe and proper completion of laparoscopic Roux-en-Y gastric bypass, in addition to various alternatives that can be helpful when other procedures are performed on morbidly obese patients.

Primary ventral hernias and ventral incisional hernias have been a challenge for surgeons throughout the ages. In the current era, incisional hernias have increased in prevalence due to the very high number of laparotomies performed in the 20(th) century. Even though minimally invasive surgery and hernia repair have evolved rapidly, general surgeons have yet to develop the ideal, standardized method that adequately decreases common postoperative complications, such as wound failure, hernia recurrence and pain. The evolution of laparoscopy and ventral hernia repair will be reviewed, from the rectoscopy of the 4(th) century to the advent of laparoscopy, from suture repair to the evolution of mesh reinforcement. The nuances of minimally invasive ventral and incisional hernia repair will be summarized, from preoperative considerations to variations in intraoperative practice. New techniques have become increasingly popular, such as primary defect closure, retrorectus mesh placement, and concomitant component separation. The advent of robotics has made some of these repairs more feasible, but only time and well-designed clinical studies will tell if this will be a durable modality for ventral and incisional hernia repair.

After introducing the concepts of extended aggregation function and extended ordered weighted average (OWA) operator, we investigate the solutions of a mathematical programming problem involving this last kind of operators and from the unique solution obtained we find a class of extended OWA operators which are, in some cases, monotonic with respect to the orderings that we consider in the definition of extended aggregation function.

The Veress needle technique for establishing pneumoperitoneum is widely used yet associated with slow insufflation and potentially life-threatening complications. The open or Hasson technique is relatively safer but considered cumbersome by many. We describe a mini-open technique that uses a 5-mm transumbilical incision and placement of a 5-mm blunt cannula without the trocar. We have employed this technique for 4 years in 600 patients without a midline laparotomy incision incorporating the umbilicus and have accessed the abdomen safely for laparoscopy without any complications. The time from skin incision to the start of the procedure is usually under 2 minutes. Our umbilical stalk technique provides rapid and safe access to the abdomen, eliminating the dangers of a blind sharp needle or trocar insertion and the need for a larger incision with placement of stay sutures. We recommend this simple technique for entry into the uncomplicated abdomen.

The historical record of daily sunspot areas (1874 - 1989) has been analysed, looking for the short (155 days) and intermediate (323 and 540 days) term periodicities. Also the North - South asymmetry during those years has been studied.

Informed consent entails a process which involves more than signing a form to give one's consent. This process involves the mutual exchange of information, understanding, trust and consent between physician and patient. The purpose of this study is that of ascertaining the degree to which those consumers who have gone through the informed consent process in a health care district in Catalonia have filled out and fully understood this form.Telephone survey conducted among 314 former surgery patients at hospitals in a given district, ages 18-75, who had undergone surgery within the three months immediately prior to the date on which the survey was conducted for the purpose of ascertaining the opinion of these consumers regarding the consent process. A review of the clinical records of 30% of these individuals was conducted for the purpose of ascertaining the degree of compliance with the consent form process.Sixty-one percent (61%) of the patients surveyed remembered having signed the consent form, 59.2% recalling explanations regarding risks or complications of the surgery they were to undergo. Nine percent (9%) did not understand well enough what was going to be done to them during the surgery, and 36% were of the understanding that the consent form released the health care professionals from liability. A statistically significant relationship was found to exist among the age group, educational level and admissions channel. Seventy-eight percent (78%) of the clinical records reviewed included informed consent forms. The diagnosis was stated on 14.9% of these forms, and 48.9% had been signed by the attending physician. A statistically significant relationship was found between the channels through which patients were admitted to the hospital.The informed consent process is not being implemented correctly at the two hospitals analyzed. Physicians are not totally involved in the process.

This study evaluated the effectiveness of psychodrama groups with traumatized middle-school girls. Comparisons of treatment and control group members' pre- and postintervention adjustment revealed significant decreases in group participants' self-reported difficulties in withdrawn behavior and anxiety/depression. Interviews with the participants reinforced the value of psychodrama group participation in the resolution of trauma and in increasing a sense of competence and self-efficacy. A brief outline of the group structure and a description of the process offer examples that illustrate the practice methodology and provide guidance for conducting psychodrama groups with vulnerable populations. Concerns with safety and containment are addressed.