Unlocking the Potential of High Entropy Alloys in Electrochemical Water Splitting: A Review.

The global pursuit of sustainable energy is focused on producing hydrogen through electrocatalysis driven by renewable energy. Recently, High entropy alloys (HEAs) have taken the spotlight in electrolysis due to their intriguing cocktail effect, broad design space, customizable electronic structure, and entropy stabilization effect. The tunability and complexity of HEAs allow a diverse range of active sites, optimizing adsorption strength and activity for electrochemical water splitting. This review comprehensively covers contemporary advancements in synthesis technique, design framework, and physio-chemical evaluation approaches for HEA-based electrocatalysts. Additionally, it explores design principles and strategies aimed at optimizing the catalytic activity, stability, and effectiveness of HEAs in hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and overall water splitting. Through an in-depth investigation of these aspects, the complexity inherent in constituent element interactions, reaction processes, and active sites associated with HEAs is aimed to unravel. Eventually, an outlook regarding challenges and impending difficulties and an outline of the future direction of HEA in electrocatalysis is provided. The thorough knowledge offered in this review will assist in formulating and designing catalysts based on HEAs for the next generation of electrochemistry-related applications.

Constructing Nitrogen-Doped Carbon Hierarchy Structure Derived from Metal-Organic Framework as High-Performance ORR Cathode Material for Zn-Air Battery.

The development of efficient and low-cost catalysts for cathodic oxygen reduction reaction (ORR) in Zn-air battery (ZAB) is a key factor in reducing costs and achieving industrialization. Here, a novel segregated CoNiPt alloy embedded in N-doped porous carbon with a nanoflowers (NFs)-like hierarchy structure is synthesized through pyrolyzing Hofmann-type metal-organic frameworks (MOFs). The unique hierarchical NFs structure exposes more active sites and facilitates the transportation of reaction intermediates, thus accelerating the reaction kinetics. Impressively, the resulting 15% CoNiPt@C NFs catalyst exhibits outstanding alkaline ORR activity with a half-wave potential of 0.93 V, and its mass activity is 7.5 times higher than that of commercial Pt/C catalyst, surpassing state-of-the-art noble metal-based catalysts. Furthermore, the assembled CoNiPt@C+RuO2 ZAB demonstrates a maximum power density of 172 mW cm-2 , which is superior to that of commercial Pt/C+RuO2 ZAB. Experimental results reveal that the intrinsic ORR mass activity is attributed to the synergistic interaction between oxygen defects and pyrrolic/graphitic N species, which optimizes the adsorption energy of the intermediate species in the ORR process and greatly enhances catalytic activity. This work provides a practical and feasible strategy for synthesizing cost-effective alkaline ORR catalysts by optimizing the electronic structure of MOF-derived catalysts.

Surgical management of Rathke cleft cysts in pediatric patients: a single institution experience.

OBJECTIVE: Rathke cleft cysts (RCCs) are benign, epithelial-lined sellar lesions that arise from remnants of the craniopharyngeal duct. Due to their rarity in the pediatric population, data are limited regarding the natural history and optimal management of growing or symptomatic RCCs. We present our institutional experience with the surgical management of RCCs. METHODS: We performed a retrospective study of consecutive RCC patients ≤ 18 years old treated surgically at our institution between 2006 and 2022. RESULTS: Overall, 567 patients with a diagnosis of pituitary mass or cyst were identified. Of these, 31 had a histopathological diagnosis of RCC, 58% female and 42% male. The mean age was 13.2 ± 4.2 years. Presenting symptoms included headache (58%), visual changes (32%), and endocrinopathies or growth delay (26%); 13% were identified incidentally and subsequently demonstrated growth on serial imaging. Six percent presented with symptomatic intralesional hemorrhage. Surgical approach was transsphenoidal for 90% of patients and orbitozygomatic for 10%. Preoperative headaches resolved in 61% of patients and preoperative visual deficits improvement in 55% after surgery. New pituitary axis deficits were seen in 9.7% of patients. Only two complications occurred from a first-time surgery: one cerebrospinal fluid leak requiring lumbar drain placement, and one case of epistaxis requiring cauterization. No patients experienced new visual or neurological deficits. Patients were followed postoperatively with serial imaging at a mean follow-up was 62.9 ± 58.4 months. Recurrence requiring reoperation occurred in 32% of patients. Five-year progression-free survival was 47.9%. Except for one patient with multiple neurological deficits from a concurrent tectal glioma, all patients had a modified Rankin Scale score of 0 or 1 (good outcome) at last follow-up. CONCLUSION: Due to their secretory epithelium, pediatric RCCs may demonstrate rapid growth and can cause symptoms due to local mass effect. Surgical management of symptomatic or growing pediatric RCCs via cyst fenestration or partial resection of the cyst wall can be performed safely, with good neurologic outcomes. There is a nontrivial risk of endocrinologic injury, and long-term follow up is needed due to high recurrence rates.

Salt-Assisted Low-Temperature Growth of 2D Bi2 O2 Se with Controlled Thickness for Electronics.

Bi2 O2 Se is the most promising 2D material due to its semiconducting feature and high mobility, making it propitious channel material for high-performance electronics that demands highly crystalline Bi2 O2 Se at low-growth temperature. Here, a low-temperature salt-assisted chemical vapor deposition approach for growing single-domain Bi2 O2 Se on a millimeter scale with thicknesses of multilayer to monolayer is presented. Because of the advantage of thickness-dependent growth, systematical scrutiny of layer-dependent Raman spectroscopy of Bi2 O2 Se from monolayer to bulk is investigated, revealing a redshift of the A1g mode at 162.4 cm-1 . Moreover, the long-term environmental stability of ≈2.4 nm thick Bi2 O2 Se is confirmed after exposing the sample for 1.5 years to air. The backgated field effect transistor (FET) based on a few-layered Bi2 O2 Se flake represents decent carrier mobility (≈287 cm2  V-1 s-1 ) and an ON/OFF ratio of up to 107 . This report indicates a technique to grow large-domain thickness controlled Bi2 O2 Se single crystals for electronics.

Going the distance in acoustic neuroma resection: microsurgical outcomes at high-volume centers of excellence.

PURPOSE: High-volume hospitals are associated with improved surgical outcomes for acoustic neuromas (ANs). Due to the benign and slow-growing nature of ANs, many patients travel to geographically distant cities, states, or countries for their treatment. However, the impact of travel burden to high-volume centers, as well as its relative benefit are poorly understood. We compared post-operative outcomes between AN patients that underwent treatment at local, low-volume hospitals with those that traveled long distances to high-volume hospitals. METHODS: The National Cancer Database was used to analyze AN patients that underwent surgery (2004-2015). Patients in the lowest quartile of travel distance and volume (Short-travel/Low-Volume: STLV) were compared to patients in the highest quartile of travel distance and volume (Long-travel/High-Volume: LTHV). Only STLV and LTHV cases were included for analysis. RESULTS: Of 13,370 cases, 2,408 met inclusion criteria. STLV patients (n = 1,305) traveled a median of 6 miles (Interquartile range [IQR] 3-9) to low-volume centers (median 2, IQR 1-3 annual cases) and LTHV patients (n = 1,103) traveled a median of 143 miles [IQR 103-230, maximum 4,797] to high-volume centers (median 34, IQR 28-42 annual cases). LTHV patients had lower Charlson/Deyo scores (p = 0.001), mostly received care at academic centers (81.7% vs. 39.4%, p < 0.001), and were less likely to be minorities (7.0% vs. 24.2%, p < 0.001) or underinsured (4.2% vs. 13.8%, p < 0.001). There was no difference in average tumor size. On multivariable analysis, LTHV predicted increased likelihood of gross total resection (odds ratio [OR] 5.6, 95% confidence interval [CI] 3.8-8.4, p < 0.001), longer duration between diagnosis and surgery (OR 1.3, 95% CI 1.0-1.6, p = 0.040), decreased length of hospital stay (OR 0.5, 95% CI 0.4-0.7, p < 0.001), and greater overall survival (Hazard Ratio [HR] 0.6, 95% CI 0.4-0.95, p = 0.029). There was no significant difference in 30-day readmission on adjusted analysis. CONCLUSION: Although traveling farther to high-volume centers was associated with greater time between diagnosis and treatment for AN patients, they experienced superior postoperative outcomes compared to patients who received treatment locally at low-volume centers. Enabling access and travel to high-volume centers may improve AN patient outcomes.

A La2O3/MXene composite electrode for supercapacitors with improved capacitance and cycling performance.

Developing efficient electrode materials is a key towards high power electrochemical energy storage devices. Two-dimensional (2D) MXene shows excellent conductivity and electrochemical performance among other materials. However, the restacking of MXene layers may degrade their specific capacity and cycling performance. Considering this challenge, here we have designed a composite made of 2D MXene nanosheets and lanthanum oxide (La2O3) nanoparticles to overcome the limitations. The bifunctionality of La2O3 nanoparticles prevents the restacking of MXene layers and enhances the electrochemical properties of the electrode due to its good Faradic characteristics. The specific capacitance of the La2O3/MXene composite electrode is 366 F/g at 1 A/g, which is 4.5 and 3 times higher than those of the individual La2O3 and MXene. The composite electrode displays a capacitance retention of 96% after 1,000 cycles, which is due to synergistic effects between the two components and indicates the potential of La2O3/MXene composite for supercapacitors.

Dissection-related tandem occlusion may be different from atherothrombotic tandem occlusion.

OBJECTIVES: The optimal endovascular treatment for tandem occlusion in anterior circulation ischaemic stroke remains unknown. The aim of this study was to examine how the aetiology of carotid pathology, dissection versus atherothrombosis, affects clinical outcomes. MATERIALS AND METHODS: Data was obtained from prospectively collected registries from two stroke centres between April 2016 and December 2020. Tandem cases with complete cervical internal carotid artery (ICA) occlusion or near-total occlusion (≥90% stenosis) were included. Patients were divided into two groups based on carotid pathology: dissection versus atherothrombosis. RESULTS: A total of 134 patients were included: 36 were dissection and 98 were atherothrombosis. The dissection group had better clinical outcomes compared to the atherothrombosis group, although after adjusting for age and stroke risk factors differences were non-significant. In the non-stented cohort, the dissection patients achieved a better outcome (modified Rankin scale 0-2) than atherothrombotic patients (57% vs. 34%, p=0.04) at 90-days. CONCLUSION: Dissection-related tandem occlusions appear to have different clinical features from atherothrombotic tandem occlusions which suggests different management strategies are needed.

In Situ Encapsulation of Graphene Quantum Dots in Highly Stable Porphyrin Metal-Organic Frameworks for Efficient Photocatalytic CO2 Reduction.

Photocatalytic CO2 reduction to valuable hydrocarbon solar fuel is of great significance but still challenging. Strong CO2 enrichment ability and easily adjustable structures make metal-organic frameworks (MOFs) potential photocatalysts for CO2 conversion. Even though pure MOFs have the potential for photoreduction of CO2, the efficiency is still quite low due to rapid photogenerated electron-hole recombination and other drawbacks. In this work, graphene quantum dots (GQDs) were in situ encapsulated into highly stable MOFs via a solvothermal method for this challenging task. The GQDs@PCN-222 with encapsulated GQDs showed similar Powder X-ray Diffraction (PXRD) patterns to PCN-222, indicating the retained structure. The porous structure was also retained with a Brunauer-Emmett-Teller (BET) surface area of 2066 m2/g. After incorporation of GQDs, the shape of GQDs@PCN-222 particles remained, as revealed by the scanning electron microscope (SEM). As most of the GQDs were covered by thick PCN-222, it was hard to observe those GQDs using a transmission electron microscope (TEM) and a high-resolution transmission electron microscope (HRTEM) directly, the treatment of digested GQDs@PCN-222 particles by immersion in a 1 mM aqueous KOH solution can make the incorporated GQDs visible in TEM and HRTEM. The linker, deep purple porphyrins, make MOFs a highly visible light harvester up to 800 nm. The introduction of GQDs inside PCN-222 can effectively promote the spatial separation of the photogenerated electron-hole pairs during the photocatalytic process, which was proved by the transient photocurrent plot and photoluminescence emission spectra. Compared with pure PCN-222, the obtained GQDs@PCN-222 displayed dramatically enhanced CO production derived from CO2 photoreduction with 147.8 µmol/g/h in a 10 h period under visible light irradiation with triethanolamine (TEOA) as a sacrificial agent. This study demonstrated that the combination of GQDs and high light absorption MOFs provides a new platform for photocatalytic CO2 reduction.

Cerebrovascular disease in sickle cell disease.

Sickle cell disease (SCD) is the most common type of hereditary anaemia and genetic disorder worldwide. Cerebrovascular disease is one of its most devastating complications, with consequent increased morbidity and mortality. Current guidelines suggest that children and adults with SCD who develop acute ischaemic stroke should be transfused without delay. Those with acute ischaemic stroke aged over 18 years who present within 4.5 hours of symptom onset should be considered for intravenous thrombolysis; older patients with conventional vascular risk factors are the most likely to benefit. Endovascular thrombectomy should be considered carefully in adults with SCD as there are few data to guide how the prevalence of cerebral vasculopathy may confound the expected benefits or risks of intervention. We present a practical approach to cerebrovascular disease in sickle cell patients based on the available evidence and our experience.

The PASTIS trial: Testing tadalafil for possible use in vascular cognitive impairment.

INTRODUCTION: There are few randomized clinical trials in vascular cognitive impairment (VCI). This trial tested the hypothesis that the PDE5 inhibitor tadalafil, a widely used vasodilator, increases cerebral blood flow (CBF) in older people with symptomatic small vessel disease, the main cause of VCI. METHODS: In a double-blind, placebo-controlled, cross-over trial, participants received tadalafil (20 mg) and placebo on two visits ≥7 days apart (randomized to order of treatment). The primary endpoint, change in subcortical CBF, was measured by arterial spin labelling. RESULTS: Tadalafil increased CBF non-significantly in all subcortical areas (N = 55, age: 66.8 (8.6) years) with greatest treatment effect within white matter hyperintensities (+9.8%, P = .0960). There were incidental treatment effects on systolic and diastolic blood pressure (-7.8, -4.9 mmHg; P < .001). No serious adverse events were observed. DISCUSSION: This trial did not identify a significant treatment effect of single-administration tadalafil on subcortical CBF. To detect treatment effects may require different dosing regimens.

PRESERVE: Randomized Trial of Intensive Versus Standard Blood Pressure Control in Small Vessel Disease.

[Figure: see text].

Culturally-adapted behavioral intervention to improve colorectal cancer screening uptake among foreign-born South Asians in New Jersey: the Desi Sehat trial.

Objectives: Colorectal cancer (CRC) is the third most common cancer among Americans of South Asian (SA) descent and is a significant public health concern in SA communities. Rates of screening compliance among foreign-born SAs are very low. The goal of this study was to report on the development, acceptability, and preliminary impact of a culturally-targeted 1:1 intervention delivered in English, Hindi, and Urdu, called Desi-Sehat.Design: Ninety-three foreign-born SAs between the ages of 50 and 75 were recruited using community-based organization methods. Participants completed a baseline survey, participated in a 1:1 session with a community health educator, and a follow-up survey was administered four months after the baseline.Results: The acceptance rate was moderate (52.8%). Attendance at the intervention session was high. More than half of the population did not complete the follow-up survey (58.7%). Participant evaluations of the intervention were high. Intent-to-treat analyses indicate a 30% four month follow-up CRC screening uptake. There were significant increases in knowledge and significant reductions in perceived barriers to screening, worry about CRC screening tests, and worry about CRC. Effect sizes for significant changes were in the medium to large range.Conclusions: Desi Sehat was a well-evaluated and participation in the session was high, participant knowledge significantly increased, and screening barriers, worry about CRC, and worry about CRC screening tests declined significantly. Future studies should focus on enhancing recruitment and retention and include a randomized control design.

The association of neutrophil-lymphocyte ratio and lymphocyte-monocyte ratio with 3-month clinical outcome after mechanical thrombectomy following stroke.

BACKGROUND AND AIM: Neutrophil-lymphocyte ratio (NLR) and lymphocyte-monocyte ratio (LMR) are associated with clinical outcomes in malignancy, cardiovascular disease and stroke. Here we investigate their association with outcome after acute ischaemic stroke treated by mechanical thrombectomy (MT). METHODS: Patients were selected using audit data for MT for acute anterior circulation ischaemic stroke at a UK centre from May 2016-July 2017. Clinical and laboratory data including neutrophil, lymphocyte and monocyte count tested before and 24 h after MT were collected. Poor functional outcome was defined as modified Rankin Scale (mRS) of 3-6 at 3 months. Multivariable logistic regression analyses were performed to explore the relationship of NLR and LMR with functional outcome. RESULTS: One hundred twenty-one patients (mean age 66.4 ± 16.7, 52% female) were included. Higher NLR (adjusted OR 0.022, 95% CI, 0.009-0.34, p = 0.001) and lower LMR (adjusted OR - 0.093, 95% CI (- 0.175)-(- 0.012), p = 0.025) at 24-h post-MT were significantly associated with poorer functional outcome when controlling for age, baseline NIHSS score, infarct size, presence of good collateral supply, recanalisation and symptomatic intracranial haemorrhage on multivariate logistic regression. Admission NLR or LMR were not significant predictors of mRS at 3 months. The optimal cut-off values of NLR and LMR at 24-h post-MT that best discriminated poor outcome were 5.5 (80% sensitivity and 60% specificity) and 2.0 (80% sensitivity and 50% specificity), respectively on receiver operating characteristic curve analysis. CONCLUSION: NLR and LMR tested at 24 h after ictus or intervention may predict 3-month functional outcome.

Synthesis of Ultrahigh-Quality Monolayer Molybdenum Disulfide through In Situ Defect Healing with Thiol Molecules.

Monolayer transition metal dichalcogenides are 2D materials with many potential applications. Chemical vapor deposition (CVD) is a promising method to synthesize these materials. However, CVD-grown materials generally have poorer quality than mechanically exfoliated ones and contain more defects due to the difficulties in controlling precursors' distribution and concentration during growth where solid precursors are used. Here, thiol is proposed to be used as a liquid precursor for CVD growth of high quality and uniform 2D MoS2 . Atomic-resolved structure characterizations indicate that the concentration of sulfur vacancies in the MoS2 grown from thiol is the lowest among all reported CVD samples. Low temperature spectroscopic characterization further reveals the ultrahigh optical quality of the grown MoS2 . Density functional theory simulations indicate that thiol molecules could interact with sulfur vacancies in MoS2 and repair these defects during the growth of MoS2 , resulting in high-quality MoS2 . This work provides a facile and controllable method for the growth of high-quality 2D materials with ultralow sulfur vacancies and high optical quality, which will benefit their optoelectronic applications.

State, religion and the marginalisation of traditional healing in Gwadar, Pakistan.

This ethnographic encounter explores suppression and domination faced by traditional health seekers in Gwadar, Pakistan. The study aimed to provide an insight into the ways in which practicing traditional healthcare becomes a challenge when it conflicts with the assimilationist project of the state. Qualitative research methods, including in-depth interviews and participant observation, were used to collect data on the encounters of traditional health seekers with the state and dominant religion. The findings show that traditional health seeking behaviour was stereotyped as non-civilised and archaic by medical staff, and labelled as non-religious, and thus, suppressed by radical Islamist groups and other state apparatuses. This situation has further negative effects on the health of traditional health seekers as the national healthcare system does not efficiently provide the services required by this population. State laws, a general environment of fear, and threats have led this population to legal consciousness and contextual awareness; they have further adopted multiple resistance strategies to navigate and circumvent oppressive laws and domination in order to follow their traditional healthcare practices. This study suggests that national cosmopolitan healthcare services provided to the fishing community should be tailored to and not suppress the culturally specific health needs of that population. Members of the fishing community should not be compelled to abstain from their traditional healthcare and health-seeking behaviours; traditional healthcare practices should be merged with cosmopolitan ones in order to address the sociocultural issues and meet the health needs of this marginalised population.

Azathioprine and the neurologist.

Neurologists are very familiar with using corticosteroids and are aware of their considerable risk of adverse effects with prolonged use. Thus, we frequently consider alternative immunosuppression or corticosteroid sparing agents. However, unlike other specialties, such as rheumatology, there are few indications for corticosteroid-sparing agents in neurology and so our experience is less extensive; even these indications may reduce further as more disease-modifying treatments become available for neurological conditions. Azathioprine is perhaps the most commonly used corticosteroid-sparing agent in neurology. This review aims to remind neurologists of important aspects of azathioprine prescribing, focussing on enhancing patient safety and clinician confidence in its prescribing.

Reduced-Intensity Conditioning with Fludarabine, Melphalan, and Total Body Irradiation for Allogeneic Hematopoietic Cell Transplantation: The Effect of Increasing Melphalan Dose on Underlying Disease and Toxicity.

Disease relapse and toxicity are the shortcomings of reduced-intensity conditioning (RIC) for allogeneic hematopoietic cell transplantation (alloHCT). We hypothesized that adding total body irradiation (TBI) to and decreasing melphalan (Mel) from a base RIC regimen of fludarabine (Flu) and Mel would increase cytoreduction and improve disease control while decreasing toxicity. We performed a phase II trial of Flu 160 mg/m2, Mel 50 mg/m2, and TBI 400 cGy (FluMelTBI-50, n = 61), followed by a second phase II trial of Flu 160 mg/m2, Mel 75 mg/m2, and TBI 400cGy (FluMelTBI-75, n = 94) as RIC for alloHCT. Outcomes were compared with a contemporaneous cohort of 162 patients who received Flu 125 mg/m2 and Mel 140 mg/m2. Eligibility criteria were equivalent for all 3 regimens. All patients were ineligible for myeloablative/intensive conditioning. The median (range) follow-up for all patients was 51 (15 to 103) months. Day 100 donor lymphoid chimerism and transplant-related mortality, neutrophil and platelet engraftment, acute and chronic graft versus host disease incidence, overall survival (OS), and progression-free survival (PFS) were equivalent between FluMel, FluMelTBI-50, and FluMelTBI-75. Stomatitis wasdecreased for FluMelTBI versus FluMel (P < .01). PFS for patients not in complete remission on alloHCT was improved for FluMelTBI-75 versus FluMel (P = .03). On multivariate analysis, OS (P = .05) and PFS (P = .05) were significantly improved for FluMelTBI-75 versus FluMel. FluMelTBI-75 is better tolerated than FluMel, with improved survival and disease control.

Clinical impact and cost-effectiveness of noncontrast MRI in the evaluation of suspected appendiceal abscesses in children.

BACKGROUND: Noncontrast MRI has been shown to be feasible in children with postappendectomy abscesses and helps guide clinical management, but its role in preoperative appendiceal abscesses is unclear. PURPOSE: To determine the cost-effectiveness and impact on clinical management of noncontrast MRI in pediatric patients with suspected appendiceal abscess, both pre- and postappendectomy. STUDY TYPE: Retrospective cohort study. POPULATION: In all, 82 children under the age of 18 years with suspected appendiceal abscess on ultrasound. FIELD STRENGTH/SEQUENCE: Diffusion-weighted imaging and T2 -weighted single-shot fast spin-echo imaging of the abdomen and pelvis at 1.5T and 3T. ASSESSMENT: The presence, location, size, and apparent diffusion coefficient (ADC) of fluid collections and the presence of a drainage path was noted by three pediatric radiologists. Imaging time, completeness of the exam, and impact on clinical management was recorded. The incremental cost-effectiveness ratio was calculated for MRI relative to CT, taking into account hospital charges, radiation exposure, and risk of adverse reaction to iodinated contrast. STATISTICAL TESTS: Descriptive statistics were used. Intraclass correlation coefficient and Fleiss' kappa were used to assess interobserver variation. Proportions were compared using Fisher's exact test (statistical significance at P < 0.05). RESULTS: MRI confirmed the presence of collections in most cases, with alternative diagnosis established in 10 patients (Tubo-ovarian abscess n = 7, Crohn's disease, ileal anastomotic leak, and Birkitts lymphoma each n = 1). MRI showed the presence of a safe drainage pathway in 92-97% of pelvic abscesses and 86-98% of abdominal abscesses compared with 7-10% and 75-81%, respectively, for ultrasound. MR was cost-effective compared with CT, taking into account the direct charges, risk of radiation induced cancer, and adverse reaction to iodinated contrast. DATA CONCLUSION: Noncontrast MR is cost-effective and affects clinical management in a significant proportion of children with suspected appendiceal abscesses. LEVEL OF EVIDENCE: 5 Technical Efficacy: Stage 6 J. Magn. Reson. Imaging 2019.

History of malignancy and relevant symptoms may predict a positive computed tomography enterography in obscure gastrointestinal bleeds.

BACKGROUND AND AIM: This study aimed to assess the clinical utility of computed tomography enterography (CTE) and identify factors associated with a diagnostic CTE for patients with obscure gastrointestinal bleeding (OGIB). METHODS: A retrospective observational study was performed at a Canadian tertiary care center from 2005 to 2015. A total of 138 patients underwent a CTE for OGIB. Univariate and multivariate logistic regressions were performed to determine factors associated with a diagnostic CTE. A highly sensitive clinical rule was then developed to help identify OGIB patients for whom a CTE may be beneficial in their clinical work-up. RESULTS: A possible bleeding source was identified in 30 (22%) cases. The presence of abdominal or constitutional symptoms as well as history of colorectal cancer was significantly associated with a positive CTE in univariate and multivariate analyses (P < 0.05). A positive CTE could be predicted based on the presence of abdominal or constitutional symptoms and history of colorectal cancer with 90% sensitivity (95% CI 74-98%) in our population. CONCLUSION: CTE identified a possible source of OGIB in one in five cases. In patients with the presence of abdominal or constitutional symptoms and a personal history of colorectal cancer, CTE may contribute to their diagnostic work-up.

Palladium nanoparticles synthesis, characterization using glucosamine as the reductant and stabilizing agent to explore their antibacterial & catalytic applications.

Low cost and an easy technique for the synthesis of palladium nanoparticles (PdNPs) was developed. Glucosamine was used to stabilize palladium precursor (PdCl2) into palladium nanoparticles. Several analytical techniques were used for the determination of morphology, crystalline structure; size, capping, and composition of synthesize palladium nanoparticles. The UV-visible spectroscopy SPR peak (Surface Plasmon Resonance) at 284 nm revealed synthesis of PdNPs. Energy dispersive X-ray (EDX) and X-ray diffraction (XRD) studies proved the elemental composition and crystalline structure of the synthesized palladium nanoparticles respectively. The average particle sizes (5.5 nm) were obtained by using the 1 M glucosamine solution, with a fixed amount of PdCl2 (4 mM). Moreover, the as synthesized PdNPs was evaluated against Gram negative bacterial E. which shows tremendous antibacterial activity as compare to tobramycin standard antibiotics. It's mechanistically found that PdNPs damage cell membrane and caused imbalance of metabolism system of the cell as a result production of reactive oxygen species (ROS). Thus, these finding revealed that cells become leaky and all organelles come out from cells, finally caused death of the E. coli. Addition, the as prepared PdNPs also showed excellent catalytic activities toward reduction of methylene blue and 4-nitrophenol.Thus, glucosamine mediated PdNPs having dual functions biomedical as well as intoxicating catalyst for industries.