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Although the concepts of nonuniform sampling (NUS​​​​​​​) and non-Fourier spectral reconstruction in multidimensional NMR began to emerge 4 decades ago (Bodenhausen and Ernst, 1981; Barna and Laue, 1987), it is only relatively recently that NUS has become more commonplace. Advantages of NUS include the ability to tailor experiments to reduce data collection time and to improve spectral quality, whether through detection of closely spaced peaks (i.e., “resolution”) or peaks of weak intensity (i.e., “sensitivity”). Wider adoption of these methods is the result of improvements in computational performance, a growing abundance and flexibility of software, support from NMR spectrometer vendors, and the increased data sampling demands imposed by higher magnetic fields. However, the identification of best practices still remains a significant and unmet challenge. Unlike the discrete Fourier transform, non-Fourier methods used to reconstruct spectra from NUS data are nonlinear, depend on the complexity and nature of the signals, and lack quantitative or formal theory describing their performance. Seemingly subtle algorithmic differences may lead to significant variabilities in spectral qualities and artifacts. A community-based critical assessment of NUS challenge problems has been initiated, called the “Nonuniform Sampling Contest” (NUScon), with the objective of determining best practices for processing and analyzing NUS experiments. We address this objective by constructing challenges from NMR experiments that we inject with synthetic signals, and we process these challenges using workflows submitted by the community. In the initial rounds of NUScon our aim is to establish objective criteria for evaluating the quality of spectral reconstructions. We present here a software package for performing the quantitative analyses, and we present the results from the first two rounds of NUScon. We discuss the challenges that remain and present a roadmap for continued community-driven development with the ultimate aim of providing best practices in this rapidly evolving field. The NUScon software package and all data from evaluating the challenge problems are hosted on the NMRbox platform.

Objectives To investigate the role of ethnicity in COVID-19 outcome disparities in a cohort in Kuwait. Methods This is a retrospective analysis of 405 individuals infected with SARS-CoV-2 in Kuwait. Outcomes such as symptoms severity and mortality were considered. Multivariate logistic regression models were used to report the odds ratios (OR) for ICU admission and dying from COVID-19. Results The cohort included 290 Arabs and 115 South Asians. South Asians recorded significantly higher COVID-19 death rates compared to Arabs (33% vs. 7.6%, P value, Highlights • Kuwait is a multiethnic country with a population of 4.3 million made mostly by Arabs and South Asians. • South Asians were more likely to develop a severe form of the disease which also corresponded to a higher death rate compared to Arabs in Kuwait. • Results highlighted probable impact of ethnicity on COVID-19 outcome.

The objective was to evaluate the distribution of the cross-sectional area (CSA) and flattening ratio (FR) of the median nerve (MN) in asymptomatic academic dentists using ultrasonography (US). Fifty academic dentists underwent US of the MN in transverse section at the pisiform bone level and the CSA (mm2) and FR were measured bilaterally. A CSA of 2 was considered normal. Paired t-test showed no statistical significance between either hand for CSA and FR ( P> .05). Two independent t-tests showed significant statistical differences ( P= .023) between males and females in the right dominant hand for CSA. Linear correlation analysis showed no significant correlation between CSA and FR for number of years of experience or number of working hours per day in either hand ( P>.05). The CSA was abnormal in the right dominant hand in 20 (40%) of the subjects. These male academic dentists were at increased risk of having an enlarged MN without symptoms.

Factor V Leiden (FVL; G1691A) is an autosomal dominant mutation with a high risk for thrombosis. Speculation that founders of FVL lived in the Middle East is supported by a prevalence of FVL that is higher in Arabs residing in Israel, Jordan, Lebanon, and Syria (12-14%) than in other white populations like Europeans (4-5%, up to 15% in the South of Sweden). We sought to verify the appropriate use of skin color as a clinical sign by which Arab individuals in Kuwait are included or excluded from testing for FVL. After institutional approval, 200 healthy Arabs residing in Kuwait consented to participate. Skin type was distinguished for the participants by Fitzpatrick natural skin color classification: 76 (38%) skin type II (white), 96 (48%) Mediterranean skin type IV (brown), and 28 (14%) skin type VI (black). FVL was tested by real-time PCR, and the percentage of carriers was calculated in each group. FVL was positive in 17 (8.5%) of the total subjects: 8 (10.5%) skin type II, 7 (7.3%) skin type IV, and 2 (7.1%) skin type VI. Therefore, FVL shows an even distribution in Arabs, and all Arabs residing in Kuwait should be tested for FVL irrespective of skin color.

Kuwait is a desert country where the prevailing high temperatures, low humidity, and scant vegetation suggest a low prevalence of allergy. We evaluated the prevalence of atopic sensitization (presence of allergen-specific IgE) among young adult blood donors by screening a total of 505 subjects (male: female ratio 1.6) with mean age of 28.4 years (range 18-50 years). The Pharmacia CAP-Phadiatop test, which detects serum IgE specific to most common airborne allergens, was used. Some of the specific sensitizing allergens were also identified by the related CAP-RAST method. Sensitization was detected in 223 of the 505 subjects (44.2%) screened. Kuwaiti nationals had a significantly higher prevalence rate (50.2%) than non-Kuwaitis (34.2%) (chi 2 = 8.6, P0.003). The highest prevalence rate was found among male Kuwaitis (53.8%). The prevalence of current or previous allergic disease (subject-reported) was 20.6%. Bermuda grass, house-dust mite (Dermatophagoides pteronyssinus), and Chenopodium album were the most prevalent sensitizing allergens, with frequencies of 53.6%, 52.7%, and 50.9%, respectively, among the sensitized subjects (corresponding to 23.7%, 23.3%, and 22.5%, respectively) for the entire population. Sensitization increased with age, but only among the expatriates, younger Kuwaitis being as frequently sensitized as the older ones. Polysensitization was found to be common. Of the 109 CAP-RAST-positive subjects, 71 (65.1%) were sensitized to more than one allergen, and 30 of these (42.3%) were sensitized to four or more allergens. These results show that atopy is highly prevalent among young adults in Kuwait, and the higher prevalence rate among nationals than expatriates suggests the involvement of genetic or local environmental factors. The results also confirm that mite and plant pollens may be major sensitizing allergens even in a desert environment.

In this paper, a new technique is presented to discriminate between magnetizing inrush currents and internal fault currents in power transformers. The proposed technique uses two moving windows which both of them estimate magnitude of differential current of power transformer by different methods. The first moving window method is based on full-cycle Fourier algorithm (long window) and the second one is originated from least error square method that has five sample point input data (short window). The proposed technique presents a new criterion for discrimination between inrush currents and internal fault currents using the difference between output values of the two moving windows. Obtained results demonstrate precise operation of the proposed algorithm for different conditions such as CT saturation condition. PSCAD/EMTDC software is used for evaluating performance of the proposed algorithm.

Kikuchi-Fujimoto disease (KFD) is cytologically characterized by a polymorphous lymphoid cell population, abundant karyorrhectic debris and histiocytes, many of which are crescentic (Kikuchi histiocytes). As per reviewed literature, KFD may be confused with tuberculosis, lymphoma, and reactive hyperplasia of lymph nodes (RHLN). Since RHLN was found to be a major challenging factor during routine cytodiagnosis of KFD in our material, we tried to find out the differentiating clinico-cytologic features between 76 KFD and 684 RHLN cases seen in Kuwait. 63.2% of KFD were in 3rd and 4th decades of life as compared to 40.2% of RHLN (P = 0.0002). Male to female ratio was 1: 2.45 for KFD and 1:1.09 for RHLN (P = 0.0022). Kuwaiti:non-Kuwaiti ratio was 1:2.04 for KFD and 1.31:1 for RHLN (P0.0001). Capillary networks was present in 71.1% of KFD smears and 52.6% of RHLN (P = 0.0023). Tingible body macrophages and dendritic reticulum cells were detected in 17.1% and 22.4%, respectively, in KFD as opposed to 50.1% and 58.8%, respectively, in RHLN (P0.0001). Kikuchi histiocyte count ranged from 2 to 36% in KFD and was ≥10% in 31 (40.8%). Rare Kikuchi histiocytes were detected in 16 (2.3%) of RHLN cases but in none of them the count exceeded 1%, whereas their count was1% in all KFD cases (P0.0001). Thus, KFD cases differed significantly from RHLN in respect of age and sex distribution, Kuwaiti:non-Kuwaiti ratio, and cytomorphologic features such as capillary networks, Kikuchi histiocyte count, dendritic reticulum cells, and tingible body macrophages.

Alterations of trace element concentrations in plasma and liver tissues in four groups of animals were investigated: group A, septic animals treated with superoxide dismutase; group B, septic animals

Purpose.To determine whether flexion contracture continues to improve up to 5 years after total knee arthroplasty (TKA).Methods.Records of 200 women and 123 men (mean age, 72 years) with osteoarthritis and preoperative flexion contracture were reviewed. 155 (48%) involved the left knee and 168 (52%) the right knee. Patients were assessed clinically before TKA and one and 5 years later, by a single researcher using a goniometer to measure flexion contracture, range of movement, maximum flexion, and the Knee Society Score. In all patients the same prosthesis design was used. The surgical technique was standard and involved a medial parapatellar approach with bone resection.Results.All variables improved significantly from pre-TKA to one-year post-TKA and from one-year post-TKA to 5-year post-TKA; respectively the mean flexion contracture decreased from 11° to 3° to 2°; the mean knee range of movement increased from 90° to 103° to 107°; the mean maximum flexion increased from 101° to 106° to 109°; and the mean Knee Society Scores increased from 39 to 87 to 90.Conclusion.Functional outcome and flexion contracture may continue to improve up to 5 years after TKA.

We studied 70 consecutive patients with adolescent idiopathic scoliosis who underwent corrective surgery. They were divided into two groups. In the study group of 38 patients one or more modern blood-conservation measures was used peri-operatively. The 32 patients in the control group did not have these measures. Both groups were similar in regard to age, body-weight, the number of levels fused and the type of surgery. Only two patients in the study group were transfused with homologous blood and these transfusions were ‘off-protocol’. Wastage of autologous pre-donated units was minimal (6 of 83 units). By contrast, all patients in the control group were transfused with homologous blood. In the study group there was a significant decrease (p = 0.005) in the estimated blood loss when all the blood-conservation methods were used. The use of blood-conservation measures, the lowering of the haemoglobin trigger for transfusion and the education of the entire team involved in the care of the patient can prevent the need for homologous blood transfusion in patients undergoing surgery for adolescent idiopathic scoliosis.

Recent studies show that structural parameters of bone, obtained from computerized image analysis of radiographs, can improve the noninvasive determination of bone strength when used in conjunction with bone density measurements. The present study was designed to assess the ability of image features alone to predict the mechanical characteristics of bones. A multifactorial model was used to incorporate simultaneously a number of characteristics of the image, including periodicity and spatial orientation of the trabeculae. Fifteen pairs (29 specimens) of unembalmed human distal radii were used. The cancellous bone structure was determined using computerized spectral analysis of their radiographic images and the bones were tested to failure under compression. Multilayered perceptron neural networks were used to integrate the various image parameters reflecting the periodicity and the spatial distribution of the trabeculae and to predict the mechanical strength of the specimens. The correlation between each of the isolated image parameters and bone strength was generally significant, but weak. The values of mechanical parameters predicted by the neural networks, however, had a very high correlation with those observed, namely 0.91 for the load at fracture and 0.93 for the ultimate stress. Both these correlations were superior to those obtained with dual-energy X-ray absorptiometry and with the cross-sectional area from CT scans: 0.87 and 0.49 respectively. Our observation suggests that image parameters can provide a powerful noninvasive predictor of bone strength. The simultaneous use of various parameters substantially improved the performance of the system. The multifactorial architecture applied is nonlinear and possibly more effective than traditional multicorrelation methods. Further, this system has the potential to incorporate other non-image parameters, such as age and bone density itself, with a view to improving the assessment of the risk of fracture for individual patients.

Abstract This study reports reservoir geochemistry findings on the Greater Burgan field by a multidisciplinary, multiorganizational team. The major objectives were to determine if unique oil fingerprints could be identified for the major producing reservoirs and if oil fingerprinting could be used to identify wells with mixed production because of wellbore mechanical problems. Three potential reservoir geochemistry applications in the Burgan field are:evaluation of vertical and lateral hydrocarbon continuityidentification of production problems due to leaky tubing strings or leaks behind casing andallocation of production to individual zones in commingled wells. The latter two applications are especially important in many older fields, such as Burgan, where tubing and casing string leaks are a problem. For example, Burgan wells which produce Wara oil up the casing and Third Burgan oil up the tubing need to be monitored for the occurrence of mechanical problems. In this case, the chromatography method adds value by reducing the number of high-cost production logging runs and eliminating the associated lost production. Results from this study showed that oils from the major reservoir units are different from each other, even though the differences are small. Furthermore, a number of wells were identified where mixed oils were being produced because of previous mechanical problems. Both transient pressure testing and distributed pressure measurements provided corroborative evidence of some of these findings. Other data showed that Third Burgan oils were different in the Burgan and Magwa sectors, suggesting a lack of communication across the central graben fault complex. This finding supported the geologic model for the ongoing reservoir simulation studies. Success of the geochemistry project has spawned enlargement of the study, both in terms of size and scope. Introduction This paper describes the results from a joint project by Chevron Overseas Petroleum, the Kuwait Oil Company (KOC) and the Kuwait Institute for Scientific Research (KISR). About 50 oils were analyzed to assess the feasibility of applying reservoir geochemisty in the Burgan field. All analytical work was performed at KISR. Reservoir geochemistry involves the study of reservoir fluids (oil, gas and water) to determine reservoir properties and to understand the filling history of the field. Many of the established methods for exploration geochemistry can be used for this purpose. Reservoir geochemistry differs from other reservoir characterization methods by dealing primarily with the detailed molecular properties of the fluids in the C, -C35+ region rather than physical properties. A review of many of these methods can be found in Larter. Geochemistry techniques have been used to help solve reservoir problems for many years. During this time, oil geochemistry has been applied to the following reservoir characterization and management problems:–Evaluation of hydrocarbon continuity–Analysis of commingled oils for production allocation–Identification of wellbore mechanical problems–Evaluation of workovers–Production monitoring for EOR–Identification of reservoir fluid type from rock extracts–Characterization of reservoir bitumens and tar mats Many different analytical techniques have been used in these reservoir geochemistry studies. One of the most widely used is gas chromatography. When used for oil correlation it is often referred to as oil fingerprinting. In most reservoirs, the oil composition represents a unique fingerprint of the oil, which can be used for correlation purposes. This is an inexpensive method and can be very cost effective when compared to many production logging methods. P. 385^

PURPOSE: The purpose of this study was to compare the properties of the median nerve and the flexor retinaculum within the carpal tunnel with Magnetic Resonance Imaging (MRI) under two conditions: (a) fingers extended, and (b) fingers in an isometric squeeze grip. METHODS: Thirty-Four volunteers participated in this experimental study. The flexor retinaculum and median nerve characteristics were measured during both conditions using MRI. RESULTS: The isometric squeeze grip condition resulted in significant palmar bowing of the flexor retinaculum (t = 7.67, p

The H-Oil process is a very complex unit used to upgrade vacuum residues to lighter product by catalytic hydrotreating and hydrocracking at reasonably high pressure and temperature. It is an important operation at the Shuaiba Refinery of Kuwait National Petroleum Company (KNPC). Depsite considerable research conducted by its licenser and other organizations the technology is still not well understood. However, this can be enhanced through the development of reliable models which can predict the hydrodynamics and product slate due to changes in process or operation parameters. This contribution demonstrates how neural network can be used as an operational support tool for H-Oil process by providing the insight into the multiphase bed behaviour and predicting a complete picture of the product slate. The ebullated-bed behaviour is characterised by a hydraulic model expressed in term of ebullated rate, catalyst loading, catalyst addition rate, and gas and liquid feed rates. The reaction model is used to predict the product slate covering naphtha, kerosene, light diesel, fractionator bottoms and 975oF+ conversion.

A prospective study of 394 burned children (in-patients) up to the age of 12 years old was carried out for the period from January 1984 to December 1986. They were categorized into three age groups, the infants and toddlers 0–2 years, early childhood 3–6 years and late childhood 7–12 years. In the first two groups scalding was the predominant cause of injury, while in late childhood there were many more flame burns. Ninety-five per cent of the accidents occurred at home and the majority happened in the presence of parents. The presence of parents was not a deterrent to the accident but ensured speedy transport to the hospital. In our review 3 per cent of patients sustained more than 50 per cent BSA burns, there were 12 deaths with a mortality rate of 3 per cent. An intense campaign to make parents aware of the risk factors and their avoidance is required to reduce the number of burn accidents.