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The variable success in learning a second language (L2) may be best explained by varying degrees of motivation. This study investigated whether individual differences in appraisal dimensions of motivation explained explicit and implicit syntactic knowledge. Participants learned three syntactic structures under implicit and explicit training conditions. They also completed two motivation questionnaires before instruction. Syntactic development was assessed at early and late stages of acquisition. Results indicated superior performance on the tests of explicit knowledge, but a limited effect for the role of motivation in its development. However, with improvement in implicit knowledge at delayed testing, positive relationships emerged with several motivational dimensions. The results support L2 theoretical perspectives that posit different roles for explicit and implicit knowledge at early and late stages of L2 grammar, respectively. The findings also indicate that variation in learners' patterns of stimulus appraisals may contribute to variable success in the development of implicit knowledge.

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Palpation is one of the applied methods that surgeons usually use during surgery in order to verify the health condition of a tissue/organ. In fact, most of surgical assessments are based on analysis of the force feedback received from tissue/organ via palpation. Although palpation has a key role in efficient progress of surgery operations, it depends very much on the experience and skill of the surgeons. This limits the application of this technique in some cases to a large extent. In this regard, an artificial tactile sensing approach is an innovative technology that tries to make tactile data more available for surgeons, especially in situations where doing the palpation is not possible or is too difficult. In this paper, having considered the present problems of artery bypass surgery in peripheral arterial occlusive disease (PAOD), applicability of a new tactile sensory system capable of detecting arterial stenosis during surgery was evaluated. Presenting the modelling and numerical solution of the problem, it was demonstrated that the artificial tactile sensing approach is not only capable of detecting the presence of an arterial stenosis in an artery, but also its type. Furthermore, it was shown that the new tactile sensory system (previously designed, fabricated and tested in laboratory) is efficiently capable of detecting the simulated artery in the simulated biological tissue as well as diagnosis of the stenosis occurred inside it.

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Abdominal aortic aneurysm is one of the most common diseases of the vascular system for which the most definitive treatment is surgery. Laparoscopy is a primary method of minimally invasive surgery that could be useful in aortic repair surgeries. Although this method of surgery has significant advantages, the difficulty of exactly distinguishing the aorta from its surrounding tissues is its main drawback; this can cause many problems during the aorta cross clamping process. One of the most important limitations is that it is a time-consuming process; aorta cross clamping leads to increases in surgery duration. Artificial tactile sensing is an innovative technology aiming to make tactile data more available for surgeons, especially in situations where developments in technology make the surgeons less efficient. In this paper, considering the present problems during aortic repair laparoscopy, applicability of a novel tactile robotic system capable of cross clamping an artery during laparoscopy was evaluated. Having considered a small, 5-degree-of-planar-freedom robot and imitated surgeon's palpation using software, the path followed by the tip of the new tactile robotic system was extracted. It is shown that this new tactile robotic system is well capable of dissecting an artery from its adjacent tissues in a short time with an acceptable accuracy. The functional principles of the tactile robotic system capable of cross clamping the aorta during laparoscopy will also be presented.

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Combined liver kidney transplantation (LKT) can be successfully performed on patients with liver and renal failure; however, outcomes are inferior to liver transplantation alone (OLT). Our aim was to determine the indications for and outcome of LKT and whether patients with longer wait times required more frequent LKT versus OLT alone. We included 18/93 adults who underwent LKT from August 2007 to August 2010 for hepatitis C virus (HCV, n = 7), alcohol (n = 5), nonalcoholic steatohepatitis (n = 2), primary biliary sclerosis, polycystic kidney disease with liver involvement, hepatic adenomatosis, and ischemic hepatitis. Eleven were originally listed for LKT and 7 required listing for-kidney transplantation while awaiting OLT. Eight were on dialysis when first listed and 10 had a low glomerular filtration rate or known kidney disease. The mean calculated Model for End-Stage Liver Disease (MELD) score for LKT was 31.2 ± 3.54. Seven had hepatocellular carcinoma in explants. Two patients had acute cellular kidney rejection that responded to treatment. Recurrence of HCV was documented in 5 patients within 6 months of LKT; 2/5 received HCV therapy (interferon and ribavirin) without renal allograft rejection. One-year liver graft/patient survival was 94% after LKT. One patient died at 6 months post LKT due to severe HCV recurrence. Last mean serum creatinine level was 1.35 ± 0.28 mg/dL for LKT patients. LKT is a safe procedure with favorable outcomes even in patients with a high MELD score. Transplantation of patients with a high MELD score due to regional variations in organ allocation results in additional use of kidneys by OLT patients. Improved organ allocation algorithms in OLT would help to reduce combined transplants, sparing more kidneys.

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Venomous animal bites are a significant health problem for rural populations in many parts of the world. Herein, we report an unusual presentation of Echis carinatus sochureki bite from southern Iran. A 36 year old woman was referred to Shiraz Nemaze Hospital due to anuria, headache, gastrointestinal bleeding, nausea and vomiting and severe abdominal pain after Echis carinatus sochureki bite. According to the clinical and paraclinical evaluations, the patient was admitted with impression of acute renal failure and acute pancreatitis. Acute pancreatitis is a rare complication after snake bite. This article is the first report of acute pancreatitis after Echis carinatus sochureki bite.

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Spontaneous aortocaval fistula is a rare complication of abdominal aortic aneurysms. We describe two cases of spontaneous aortocaval fistula. The first patient is a woman who was admitted with abdominal pain and pulsatile abdominal mass. Another patient was a man admitted with progressive abdominal pain and hypotension. Computed tomography (CT) scan in both patients showed an infrarenal aortic aneurysm and simultaneous contrast enhancement in the inferior vena cava. Both patients underwent an urgent laparotomy in which the diagnosis of an aortocaval fistula was confirmed. We review the literature on spontaneous aortocaval fistula as a consequenceof complicated aortic aneurysms.

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The aim of this study was to review the aetiology and surgical technique of treatment of all femoral artery pseudo-aneurysms that had presented to our centre during the previous 9 years and to compare the results of infected femoral artery pseudo-aneurysms and other kinds of pseudo-aneurysm. This retrospective case-note study consists of all femoral pseudo-aneurysms that have been managed in Sina hospital from 1996 to 2005. The intravenous injection of drugs (n = 26), arterial access for angiography (n = 17), trauma (n = 6) and vasculitis (n = 1) were the causes of pseudo-aneurysms. Surgical repair was indicated for all patients; however, routine surgical repair techniques were modified in some patients. Two deaths and one amputation occurred in intravenous drug abusers. The most frequent cause of femoral artery pseudo-aneurysm formation in our hospital is intravenous injection of drugs, which is associated with higher mortality and morbidity than other causes. In contrast to previous reports, our experience shows that triple vessel ligation (common, superficial and deep femoral arteries) can be a safe treatment for infected femoral artery pseudo-aneurysms. In addition, our results did not show the safety of common femoral artery ligation as a treatment of choice. However, it is recommended, due to the better results of elective extra-anatomic bypass than emergent extra-anatomic bypass. Repair of post-angiographic pseudo-aneurysms by interrupted sutures or patch angioplasty is associated with good results. Surgical repair of traumatic pseudo-aneurysms should be determined per case and can vary from local control to extra-anatomic bypass.

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In order to determine different protocols of synchronization and their efficiency on pregnancy rate after fixed-timed AI (TAI), 120 dairy Holstein cows (n=120) were assigned randomly to six groups: (1) two injections of Prostaglandin F(2alpha) (PG(f2alpha)) with 12 days apart as a control group, (2) two injections of Gonadotropin Releasing hormone (GnRH) with 9 days apart and an injection of PG(f2alpha) at day 7, (3) injection of GnRH and PG(f2alpha) with 7 days apart, then single injection of Estradiol Benzoate (EB) after 48 h, 4) injection of progesterone (P4) in conjugation with EB then after 7 days PG(f2alpha) injection and after 48 h an injection of GnRH were done, 5) as group 4 but EB was used instead of GnRH, 6)injections of PG(f2alpha) and EB conjugated with Human Chronic Gonadotrophin (hCG) with 12 h apart. Animals in group 1 (control), groups 2-5 and group 6 were inseminated after 72, 20 and 36 h, respectively. Serum P4 concentration of group 4 (4.43 +/- 1.50 ng mL(-1)) was higher than control group (2.34 +/- 1.36 ng mL(-1)) at day 5 after insemination (p < 0.05); P4 concentrations of groups 3 and 4 have significant differences with control group (2.69 +/- 2.64 and 2.56 +/- 1.40 versus 0.81 +/- 0.41 ng mL(-1), respectively, p < 0.05) at a day after second injection and groups 4 and 5 were in higher level of P4 concentration than control group at insemination time (3.14 +/- 1.9 and 2.89 +/- 1.8 versus 0.45 +/- 0.19 ng mL(-1) respectively, p < 0.05). Pregnancy rate were 0, 50, 45, 10, 30 and 45% for group 1 (control) through 6, respectively.

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A split-flow capillary electrophoresis electrospray ionization mass spectrometry (CE/ESI-MS) interface is introduced, in which the electrical connection to the CE capillary outlet is achieved by diverting part of the CE buffer out of the capillary through an opening near the capillary outlet. The CE buffer exiting the opening contacts a sheath metal tube which acts as the CE outlet/ESI shared electrode. In cases in which the ESI source uses a metal needle, the voltage contact to the CE buffer is achieved by simply inserting the outlet of the CE capillary, which contains an opening, into the existing ESI needle (thereby greatly simplifying the CE to MS interfacing). As a result of the concentration-sensitive nature of ESI, splitting a small percentage of the CE flow has minimal effect on the sensitivity of detection. In addition, because the liquid is flowing through the opening and out of the capillary, there is no dead volume associated with this interface. Moreover, bubble formation due to redox reactions of water at the electrode does not effect CE/ESI-MS performance, because the actual metal/liquid contact occurs outside of the CE capillary. The sensitivity associated with a sheathless CE/MS interface, the ease of fabrication, universality, and lack of any dead volume make this design a superior CE/ESI-MS interface. The performance of this interface is demonstrated by analyses of a peptide standard and a protein digest using a variety of capillary dimensions.

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It was found that combining capillary electrophoresis (CE) and electrospray ionization mass spectrometry (ESI-MS) overlays two controlled current techniques to form a three-electrode system (CE inlet, CE outlet/ES emitter, and MS inlet electrodes) in which the CE outlet electrode and the ES emitter electrode were shared between the CE and the ESI-MS circuits. Depending on the polarities and magnitudes of the voltages at the CE inlet, CE outlet/ES emitter, and MS inlet electrodes, the nature of the two redox reactions at the shared electrode was the same or different (both reduction, both oxidation, or one oxidation and the other reduction). Several redox buffers were introduced for controlling electrochemical reactions at the shared electrode. By reacting at this electrode, redox buffers were able to maintain electrode potentials below the onset of water electrolysis, thereby eliminating gas bubble formation and/or pH drift. The volume of the gas generated due to water electrolysis was used to quantitate water oxidation or reduction at this electrode. Two types of redox buffers were used. A reactive electrode with an oxidation potential below that of water was used as the electrode under anodic conditions. Also, a reactive compound with a redox potential below that of water was added to the CE and/or ESI running buffer. When the shared electrode was the anode of both CE and ESI-MS circuits, the use of iron or etched and sanded stainless steel (ss) wire, instead of platinum wire, suppressed bubble formation at the shared electrode. Under these conditions, corrosion of the Fe wire and formation of Fe2+ replaced oxidation of water, eliminating O2 gas bubble and H+ formation. When mixtures of peptides were analyzed, iron adducts of peptides were observed. For a fresh wire, however, the intensities of adduct ions were less than 3% of the protonated molecules. After a few days of operation, the intensities of the adduct ions increased to approximately 50%, due to rust formation on the Fe wire. On-column rinsing with a 40% solution of citric acid rejuvenated the Fe wire and reduced the adduct peak intensities to less than 3%. Unmodified ss wire did not quench bubble formation, which was attributed to its passivated surface. When Fe, ss, and Pt wires were used as the shared electrode under forward polarity CE and positive ESI mode, where the shared electrode acted as a cathode with respect to CE inlet and as an anode with respect to MS inlet, reduction of water at the cathodic end of the electrode and, in the case of ss and Pt wires, oxidation of water at the anodic end of the shared electrode produced a significant amount of bubbles. Under these conditions, however, a buffer containing 50 mM p-benzoquinone completely suppressed both cathodic reduction and anodic oxidation of water for CE currents up to 4 microA. Reduction of p-benzoquinone at the cathodic end of the shared electrode to hydroquinone, and oxidation of this hydroquinone at the anodic end of the electrode, replaced reduction and oxidation of water, eliminating bubble formation. A 0.1% acetic acid solution saturated with I2 was also found to suppress bubble formation at the cathode for CE currents up to 3 microA; however, strong iodine adduct ions were observed under CE/ESI-MS when a mixture of peptides was analyzed. The application of iron as an in-capillary electrode for the analysis of a peptide mixture and a protein digest demonstrated a high separation efficiency similar to when hydroquinone was used as a redox buffer.

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A dual oscillating capillary nebulizer (OCN) in conjunction with an atmospheric pressure microwave induced plasma ionization (AP-MIPI) source was applied to the analysis of underivatized amino acid mixtures. It was found that, compared to the single OCN, the dual OCN enhanced the sensitivity of detection several fold. Enhanced sensitivity was compound dependent. For small molecules, such as amino acids, it was 2-5 times more sensitive, while for larger molecules such as peptides it was more than an order of magnitude. The increase in sensitivity was attributed to the enhanced nebulization of the new torch. By using water/ acetonitrile containing 0.1% nonafluoropentanoic acid as the high performance liquid chromatography (HPLC) mobile phase and a C18 column, all common amino acids were separated and detected. A comparison between the results obtained using microwave induced plasma, atmospheric pressure chemical ionization (APCI), and electrospray ionization (ESI) at flow rates compatible with micro LC (10-100 microL/min) showed a higher sensitivity of detection with the AP-MIPI technique for the analysis of underivatized amino acids.

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BACKGROUND: Because of the need to improve the quality of care of trauma patients in our country, we decided to evaluate the epidemiology and find the most powerful tool for prediction of survival. The Trauma and Injury Severity Score (TRISS) has been known as conventional method for this purpose. We planned to test its ability for prediction of survival of our trauma patients, and also we wanted to compare its ability with the New Injury Severity Score (NISS) in combination with Revised Trauma Score (RTS) and age. We used the most suitable model to evaluate the trauma care in our centers. METHODS: From the Tehran University data registry on trauma patients of three different hospitals during 1 year, we selected trauma patients admitted to hospital for at least 1 day and all those patients who were declared dead at the emergency department. Epidemiologic description of patients has been given and evaluation of TRISS and (NISS + RTS + age) for prediction of survival has been performed. We determined factors affecting mortality and morbidity, evaluated hospitals, and analyzed patients admitted directly and the patients transferred from other hospitals. RESULTS: A total of 2,662 patients had complete data necessary for the calculation of probability of survival based on the TRISS method. The population at risk for trauma was the young, especially students and industrial workers. The major mechanisms of trauma were road traffic crashes and falls. The time expenditure and means of transportation as well as the time of stay in emergency department all seemed to be far less than optimal. We found that TRISS has higher performance than (NISS + RTS + age). CONCLUSION: Based on our descriptive findings, we proposed some suggestions that seem to be necessary for improvement of trauma care in our centers. Among them were improved measures for prehospital service, and emergency department and other health care units of our centers. The findings of this study suggest that conducting trauma surgery training programs and direct transportation to trauma centers can improve the outcome of trauma patients. We conclude that small sample size, mixing penetrating trauma cases with blunt trauma cases, and differences in the mechanism of trauma between study populations may be responsible for the difference between our results and others.

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The atmospheric pressure sampling nozzle (orifice, heated capillary, or inlet) of a high mass accuracy time-of-flight mass spectrometer (TOF-MS) was modified by replacing its single nozzle with multiple atmospheric pressure nozzles. This allowed multiple streams of liquids to be introduced into the MS in parallel (an electrosprayer for each nozzle), with minimum analyte interactions between the streams. The chemical contents of all liquid streams were analyzed concurrently using a single mass spectrometer. To obtain a higher mass accuracy by providing internal reference on each scan (acquisition) and to evaluate the suitability of TOF-MS for molecular-formula confirmation, a dual-ESI-sprayer, dual-nozzle version of this design was used. The accurate masses of tens of organic compounds in the mass range of 200-3000 Da were measured, and the results were compared with those obtained using dual-sprayer, single-nozzle TOF-MS. A significant improvement in mass accuracy was observed when the former technique was used. Comparison between the mass accuracy using dual-ESI-sprayer, dual-nozzle TOF-MS and that obtained using a double-focusing mass spectrometer operating under chemical ionization (CI) and fast atom bombardment (FAB) shows the suitability of the technique for elemental-composition confirmation. Approximately 85% of samples analyzed had mass errors of less than 5 ppm, and the other 15% had mass errors less than 8 ppm. Using a high-performance liquid chromatography (HPLC) as a device for introduction of one liquid stream (sample) and a syringe pump as a device for introduction of the second liquid stream (reference standard), the accurate mass of a tryptic digest of cytochrome c was measured. The range of mass errors was from -6.1 ppm to +3.6 ppm, a significant improvement over our previously reported mass accuracy for this digest using single-nozzle TOF-MS. The interactions between analytes in the liquid streams also were investigated using a variety of sample-introduction and nozzle-design combinations, including single-ESI-sprayer, single-nozzle; dual-ESI-sprayer, single-nozzle; dual-ESI-sprayer, Y-shaped inlet; and dual-ESI-sprayer, dual-inlet. The results demonstrated that the dual-ESI-sprayer, dual-inlet design provides reference peaks on every acquisition with minimum analyte-reference interaction and, therefore, higher consistent mass accuracy.

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Hydroquinone was found to suppress bubble formation at the outlet electrode of a sheathless capillary electrophoresis/electrospray ionization-mass spectrometer by replacing the oxidation of water (2H2O(1)<-->O2(g) + 4H+ + 4e) with that of more easily oxidized hydroquinone (hydroquinone<-->p-benzoquinone + 2H+ + 2e). Formation of p-benzoquinone replaces the formation of oxygen gas, effectively suppressing gas bubble formation. Several electrode materials, including platinum, gold-coated stainless steel, and stainless steel wires, were tested. However, hydroquinone suppressed bubbles only at the platinum electrode. Combination of the in-capillary electrode sheathless interface using platinum wire, hydroquinone as a buffer additive, and pressure programming at the inlet of the capillary electrophoresis provided a rugged high efficiency interface for analysis of protein digests using CE/ESI-MS.

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A single intact red blood cell (erythrocyte) was injected into a capillary electrophoresis column, and following in-capillary lysing the alpha- and beta-chains of the hemoglobin (approximately 450 amol) were separated and detected using capillary electrophoresis/electrospray ionization time-of-flight mass spectrometry. The mass specta of the electropherogram peaks of the alpha and beta chains showed identifiable peaks corresponding to multiply protonated and sodiated alpha- and beta-chains of hemoglobin.

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Pressure assisting and pressure programming the inlet of the capillary electrophoresis instrument were used for the analysis of peptide mixtures and protein digests using capillary electrophoresis/electrospray ionization-mass spectrometry (CE/ESI-MS). CE/ESI-MS of peptide mixtures and tryptic digests of proteins was studied using three different types of capillary columns: (i) a freshly aminopropylsilane (APS)-treated column, (ii) an untreated column, and (iii) a degraded APS-treated column. To maintain a constant and adequate buffer flow toward the CE capillary outlet for stable CE and ESI operation, low pressure was applied to the inlet of the CE when an untreated or degraded APS capillary was used. By programming the inlet pressure, CE/ESI-MS analysis time was reduced to 1/3 of its original time. The utility of this technique is demonstrated by CE/ESI-MS analysis of a hemoglobin variant (hemoglobin-S) and its tryptic digests. Identification of the mutant peptide in the tryptic digest of hemoglobin-S was achieved by collision-induced dissociation (CID) of the protein digests using CE/ESI time of flight-mass spectrometry (TOF-MS).

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An in-capillary electrode sheathless interface was applied to the capillary electrophoresis/electrospray ionization-mass spectrometry (CE/ESI-MS) analysis of mixtures of small peptides, proteins, and tryptic digests of proteins. The effects of different experimental parameters on the performance of this CE/ESI-MS interface were studied. The distance of the in-capillary electrode from the CE outlet and the length of the electrode inside the capillary had no significant effects on the CE separation and ESI behavior under the experimental conditions used. However, significant enhancement of the sensitivity resulted from the use of narrower CE capillaries. Using a quadrupole mass spectrometer, an aminopropylsilane-coated capillary, and a wide scan mass-to-charge ratio range of 500-1400, detection limits of approximately 4, 1, and 0.6 fmol for cytochrome c and myoglobin were achieved for 75-, 50-, and 30-micron inner diameter capillaries, respectively. Approximately one order of magnitude lower detection limits were achieved under the multiple-ion monitoring mode. The application of the in-capillary electrode sheathless interface to real-world samples was demonstrated by CE/ESI-MS analysis of a human blood sample.

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Capillary electrophoresis/electrospray ionization (CE/ESI) high mass accuracy time-of-flight mass spectrometry was used for the first time to characterize small proteins using peptide mapping. To identify small proteins, the intact proteins were first analyzed to obtain their average molecular weights with errors less than 1 Da. On-line capillary electrophoresis mass spectrometry of the tryptic digests of these small proteins was then performed to obtain the accurate molecular weights of the peptides with accuracies of approximately 10 ppm. Next, this information was used for the identification of the proteins using a protein database. It was found that high mass accuracy is an effective tool in reducing the list of most-likely proteins generated by the database. In addition, on-line collision-induced dissociation of the completely or partially resolved capillary electrophoresis peaks of the protein digests was used to unambiguously identify the sequences of these peptides. Each CE/ESI-MS analysis used only 5 nL of sample containing approximately 120 fmol of each peptide in protein digests. The results indicate that the combination of capillary electrophoresis and high resolution, high mass accuracy time-of-flight mass spectrometry is a viable option for the identification of small proteins using peptide mapping.

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Nonprotein amino acids from nine species of cycad seeds were analyzed as N-ethoxycarbonyl ethyl ester (ECEE) derivatives by positive chemical-ionization gas chromatography-mass spectrometry. Based on the retention times and mass spectrometry analyses, 12 nonprotein amino acids were identified in these seeds. In addition to the excitatory and putative neurotoxin beta-N-methylamino-L-alanine (BMAA), the known neurotoxin beta-N-oxalylamino-L-alanine (BOAA) was detected from the seeds of Macrozamia moorei and M. communis, and delta-N-oxalyl-ornithine was obtained from the Cycas revoluta seeds. A novel nonprotein amino acid named cycasindene, previously reported from C. revoluta, was also found in the seeds of members of the C. angulata and C. rumphii complex. Eight additional known nonprotein amino acids were also identified. This is the first report of the neurotoxin BOAA from cycad seeds.

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