•A new CNFs based Cu/ZrO2 catalyst for CO2 hydrogenation to methanol was investigated.•CNFs served well as a catalyst support in slurry reactor for the title reaction.•N2O chemisorption studies ...revealed that SCu was significantly increased by Nb promotion.•Efficient CO2 conversion at relatively low reaction temperature.•The efficiency of the catalyst was enhanced incorporation Nb content to the catalyst.
A series of carbon nanofibres supported Cu/ZrO2/Nb2O5 catalyst synthesized by deposition precipitation method were extensively investigated in relation to their performance in hydrogenation of CO2 to methanol. In order to study the promotion effect of niobium, catalysts were loaded with 0.4, 0.8 and 1.2wt.% of Nb2O5. Incorporation of Nb2O5 facilitated copper reduction by exhibiting a shift of highly reduced copper peak to lower temperature. Likewise, surface enrichment of copper was also enhanced by introduction of Nb2O5 to the catalysts. Activity studies of Nb2O5 doped Cu/ZrO2 catalysts were evaluated in a slurry reactor with a CO2/H2 gas mixture of 1:3 volume ratio, 180oC temperature and 3.0MPa total pressure. The highest activity was achieved with the incorporation of 0.8wt.% of Nb2O5, illustrating the high degree of CuO crystallization on the surface of catalyst are beneficial for the generation of copper catalyst with enhanced activities.
Abstract The low‐lying peatlands of the Holland Marsh are intensively cultivated with high‐value vegetable crops, worth some $450 million Canadian annually. This high productivity is due to the fact ...that there have been significant investments to empolder the marsh, through the construction of dykes, embankments, canals, ditches, tile drainage, and installation of pumping stations. However, attention must be paid to the long‐term environmental sustainability of the Holland Marsh, given the high phosphorus loads and eutrophication in Lake Simcoe, the principal drainage outlet for the agricultural run‐off from the marsh. It is important that non‐point source pollution be reduced and drainage water quality better managed. In addition to agro‐environmental best management practices, adoption of controlled drainage, and improved drainage water pumping strategies are recommended. These could help achieve the P reduction target established by the government of Ontario and the Lake Simcoe Region Conservation Authority.
Résumé Les tourbières des basses terres du marais Holland font l'objet d'une culture légumière intensive à forte valeur ajoutée, rapportant près de 450 millions de dollars canadiens par année. Cette productivité élevée est liée à d'importants investissements visant à la poldérisation du marais par la construction de digues, de remblais, de canaux, de fossés, et par l'installation de drainage souterrain et de stations de pompage. Cependant, étant donné les charges élevées de phosphore et l'eutrophisation du lac Simcoe—le principal exutoire des eaux de ruissellement agricoles du marais—l'on se doit de prêter attention à la durabilité environnementale à long terme du marais Holland. Il est important d'y réduire la pollution de source non ponctuelle et de mieux gérer la qualité des eaux de drainage. En plus de pratiques exemplaires de gestion agricole., l'adoption d'un drainage contrôlé et de meilleures stratégies de pompage des eaux de drainage sont recommandées. Ces mesures pourraient aider à atteindre l'objectif de réduction du P établi par le gouvernement de l'Ontario et l'Office de protection de la nature de la région du lac Simcoe.
Learning to program involves acquisition of various skills including problem solving, fundamental design techniques as well as critical thinking. Generally, most of the novice programmers struggle to ...develop all these important skill. The research community has addressed the problem in many different ways while involving improvisations in curriculum, pedagogical methods, cognitive aspects, supporting tools, and in designing assessments. This research aims to analyze and synthesize the existing literature in the aforementioned areas. Research articles pertaining to the area of Introductory Programming Courses (IPC) have been found using appropriate search queries, while nearly 60 research articles, published in last ten years, have been carefully selected by employing a systematic filtering process. The scope of this work only covers the research conducted for IPC in higher education. Main findings of this study show that "solution proposal" and "evaluation research" have been reported as two main research types adopted by these studies. Moreover, pedagogy, language choice and students' performance analysis are the most frequently addressed aspects of IPC; whereas, curriculum contents, assessment design, and teaching/learning through tools have appeared as less addressed aspects of IPC. Furthermore, a taxonomy of IPC has been presented based on the studied literature. Lastly, general considerations and future research directions have been presented for the practitioners and researchers in this area.
Background
Previous case series report that neuroendocrine tumors (NETs) of the ampulla of Vater have worse overall survival (OS) than NETs in the duodenum. We aimed to compare the OS of patients ...with ampullary NETs to patients with duodenal NETs.
Methods
This retrospective comparative cohort study used the Surveillance, Epidemiology, and End Results (SEER) registry from 1988 to 2009. OS was evaluated using Kaplan–Meier estimates and Cox proportional hazard regression.
Results
Ampullary NETs (
n
= 120) were larger (median size 18 vs. 10 mm,
p
< 0.001), higher grade (poorly and undifferentiated tumor 42 % vs. 12 %,
p
< 0.001), higher SEER historic stage (distant metastasis 16 % vs. 7 %,
p
< 0.001), and more often resected (78 % vs. 60 %,
p
< 0.001) than duodenal NETs (
n
= 1,360). Median OS was significantly worse for patients with ampullary NETs than with duodenal NETs (98 vs. 143 months,
p
= 0.037). Local resection was performed for 50.5 % of the resected ampullary NETs and resulted in similar OS compared to locally resected duodenal NETs (HR 1.37, 95 % CI 0.76–2.48,
p
= 0.291).
Conclusions
While ampullary NETs are more advanced at presentation and have worse OS than duodenal NETs, long-term survival is possible with proximal small bowel NETs. For locally resected NETs, OS is similar between ampullary and duodenal NETs.
Background
Waiting lists for kidney transplantation continue to grow. Live kidney donation significantly reduces waiting times and improves long‐term outcomes for recipients. Major disincentives to ...potential kidney donors are the pain and morbidity associated with surgery. This is an update of a review published in 2011.
Objectives
To assess the benefits and harms of open donor nephrectomy (ODN), laparoscopic donor nephrectomy (LDN), hand‐assisted LDN (HALDN) and robotic donor nephrectomy (RDN) as appropriate surgical techniques for live kidney donors.
Search methods
We contacted the Information Specialist and searched the Cochrane Kidney and Transplant Register of Studies up to 31 March 2024 using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal, and ClinicalTrials.gov.
Selection criteria
Randomised controlled trials (RCTs) comparing LDN with ODN, HALDN, or RDN were included.
Data collection and analysis
Two review authors independently screened titles and s for eligibility, assessed study quality, and extracted data. We contacted study authors for additional information where necessary. Summary estimates of effect were obtained using a random‐effects model, and results were expressed as risk ratios (RR) and their 95% confidence intervals (CI) for dichotomous outcomes and mean difference (MD) or standardised mean difference (SMD) and 95% CI for continuous outcomes. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.
Main results
Thirteen studies randomising 1280 live kidney donors to ODN, LDN, HALDN, or RDN were included. All studies were assessed as having a low or unclear risk of bias for selection bias. Five studies had a high risk of bias for blinding.
Seven studies randomised 815 live kidney donors to LDN or ODN. LDN was associated with reduced analgesia use (high certainty evidence) and shorter hospital stay, a longer procedure and longer warm ischaemia time (moderate certainty evidence). There were no overall differences in blood loss, perioperative complications, or need for operations (low or very low certainty evidence).
Three studies randomised 270 live kidney donors to LDN or HALDN. There were no differences between HALDN and LDN for analgesia requirement, hospital stay (high certainty evidence), duration of procedure (moderate certainty evidence), blood loss, perioperative complications, or reoperations (low certainty evidence). The evidence for warm ischaemia time was very uncertain due to high heterogeneity.
One study randomised 50 live kidney donors to retroperitoneal ODN or HALDN and reported less pain and analgesia requirements with ODN. It found decreased blood loss and duration of the procedure with HALDN. No differences were found in perioperative complications, reoperations, hospital stay, or primary warm ischaemia time.
One study randomised 45 live kidney donors to LDN or RDN and reported a longer warm ischaemia time with RDN but no differences in analgesia requirement, duration of procedure, blood loss, perioperative complications, reoperations, or hospital stay.
One study randomised 100 live kidney donors to two variations of LDN and reported no differences in hospital stay, duration of procedure, conversion rates, primary warm ischaemia times, or complications (not meta‐analysed).
The conversion rates to ODN were 6/587 (1.02%) in LDN, 1/160 (0.63%) in HALDN, and 0/15 in RDN.
Graft outcomes were rarely or selectively reported across the studies. There were no differences between LDN and ODN for early graft loss, delayed graft function, acute rejection, ureteric complications, kidney function or one‐year graft loss.
In a meta‐regression analysis between LDN and ODN, moderate certainty evidence on procedure duration changed significantly in favour of LDN over time (yearly reduction = 7.12 min, 95% CI 2.56 to 11.67; P = 0.0022). Differences in very low certainty evidence on perioperative complications also changed significantly in favour of LDN over time (yearly change in LnRR = 0.107, 95% CI 0.022 to 0.192; P = 0.014). Various different combinations of techniques were used in each study, resulting in heterogeneity among the results.
Authors' conclusions
LDN is associated with less pain compared to ODN and has comparable pain to HALDN and RDN. HALDN is comparable to LDN in all outcomes except warm ischaemia time, which may be associated with a reduction. One study reported kidneys obtained during RDN had greater warm ischaemia times. Complications and occurrences of perioperative events needing further intervention were equivalent between all methods.
Nuclear degradation is a key stage in keratinocyte terminal differentiation and the formation of the cornified envelope that comprises the majority of epidermal barrier function. Parakeratosis, the ...retention of nuclear material in the cornified layer of the epidermis, is a common histological observation in many skin diseases, notably in atopic dermatitis and psoriasis. Keratinocyte nuclear degradation is not well characterised, and it is unclear whether the retained nuclei contribute to the altered epidermal differentiation seen in eczema and psoriasis. Loss of AKT1 function strongly correlated with parakeratosis both in eczema samples and in organotypic culture models. Although levels of DNAses, including DNase1L2, were unchanged, proteomic analysis revealed an increase in Lamin A/C. AKT phosphorylates Lamin A/C, targeting it for degradation. Consistent with this, Lamin A/C degradation was inhibited and Lamin A/C was observed in the cornified layer of AKT1 knockdown organotypic cultures, surrounding retained nuclear material. Using AKT-phosphorylation-dead Lamin A constructs we show that the retention of nuclear material is sufficient to cause profound changes in epidermal terminal differentiation, specifically a reduction in Loricrin, Keratin 1, Keratin 10, and filaggrin expression. We show that preventing nuclear degradation upregulates BMP2 expression and SMAD1 signalling. Consistent with these data, we observe both parakeratosis and evidence of increased SMAD1 signalling in atopic dermatitis. We therefore present a model that, in the absence of AKT1-mediated Lamin A/C degradation, DNA degradation processes, such as those mediated by DNAse 1L2, are prevented, leading to parakeratosis and changes in epidermal differentiation.
A field experiment was carried out at the field with clay loam soil in the winter seasons of 2018 - 2019 and 2019 - 2020 in order to study the effect of three levels of salt stress on yield and its ...components for four cultivars of barley (Hordeum valgare L.(. which be approved in Iraq.Factorial experiment with in Randomized Complete Block design with three replications. The treatments included three levels of irrigation water salinity (5,10,15) ds.m-1 and four cultivars of barley (IPA 99, Buhooth 265, Samir, and Amal). The results showed that the salinity of the irrigation water caused a significant decreases of the number of spikes.m-2, number of grains. spike-1, weight of 1000 grains (gm) and grain yield. plant. -1 at levels S2 and S3 and for both studies seasons in comparison with treatment S1, which gave the highest averages for the mentioned traits, significant differences among barley cultivars in terms of their tolerance to salinity. It was found that Samir cultivar was more tolerant to salinity than the other cultivars.
Excess salt affects about 955 million ha of arable land worldwide, and 49% of agricultural land is Zn-deficient. Soil salinity and zinc deficiency can intensify plant abiotic stress. The mechanisms ...by which Zn can mitigate salinity effects on plant functions are not well understood. We conducted an experiment to determine how Zn and salinity effects on rice plant retention of Zn, K
and the salt ion Na
affect chlorophyll formation, leaf cell membrane stability and grain yield. We examined the mechanisms of Zn nutrition in mitigating salinity stress by examining plant physiology and nutrition. We used native Zn-deficient soils (control), four salinity (EC) and Zn treatments - Zn 10 mg·kg
(Zn
), EC 5 dS·m
(EC
), Zn
+EC
and Zn
+EC
, a coarse rice (KS-282) and a fine rice (Basmati-515) in the study. Our results showed that Zn alone (Zn
) significantly increased rice tolerance to salinity stress by promoting Zn/K
retention, inhibiting plant Na
uptake and enhancing leaf cell membrane stability and chlorophyll formation in both rice cultivars in native alkaline, Zn-deficient soils (P < 0.05). Further, under the salinity treatment (EC
), Zn inputs (10-15 mg·kg
) could also significantly promote rice plant Zn/K
retention and reduce plant Na
uptake, and thus increased leaf cell membrane stability and grain yield. Coarse rice was more salinity-tolerant than fine rice, having significantly higher Zn/K
nutrient retention. The mechanistic basis of Zn nutrition in mitigating salinity impacts was through promoting plant Zn/K
uptake and inhibiting plant Na
uptake, which could result in increased plant physiological vigour, leaf cell membrane stability and rice productivity.
We evaluated expression of 50 genes encoding enzymes involved in metabolism, cellular growth, and various transporters in ruminal epithelium tissue when calves were fed conventional milk replacer ...(MR) and starter (control) or enhanced MR and enhanced starter. Male Holstein calves were fed reconstituted control MR 20% crude protein (CP), 20% fat; 0.57kg of solids/calf plus conventional starter (19.6% CP, dry matter basis) or a high-protein MR (ENH; 28.5% CP, 15% fat; at ∼2% of body weight) plus high-CP starter (25.5% CP, dry matter basis). Groups of calves in control and ENH were harvested after 43 d (wk 5) and 71 d (wk 10) of feeding. Ruminal epithelium from 5 calves (3 to 42 d age) in each group was used for transcript profiling using quantitative reverse transcription PCR. No differences were observed for plasma β-hydroxybutyrate (BHBA) concentration but BHBA increased by wk 10 regardless of treatment. Reticulorumen mass postweaning was greater in calves consuming the ENH diet and corresponded with overall greater serum insulin. A marked upregulation of the ketogenic genes HMGCS2, HMGCL, and BDH1 was observed, concomitant with downregulation of expression of genes involved in fatty acid oxidation (CPT1A, ACADVL) at wk 10. Higher relative percentage mRNA abundance of HMGCS2 (∼40% of total genes assayed), the rate-controlling enzyme in hepatic ketogenesis, underscored its importance for ruminal cell energy metabolism. Higher PPARA expression and blood nonesterified fatty acids at wk 5 due to ENH were suggestive of more extensive long-chain fatty acid oxidation in ruminal epithelial cells during the milk-fed phase. In contrast, calves fed control consumed more starter during the milk-fed phase, which likely increased production of volatile fatty acids and accounted for higher expression of propionyl-CoA carboxylase (PCCA) and the Na⁺/H⁺ exchanger 2 (SLC9A2) at wk 5. Expression of G-coupled protein receptors for short-chain fatty acids was undetectable. The expression of the urea transporter (SLC14A1) increased markedly with age and was correlated with the increase in blood urea N. Expression of genes involved in cell proliferation (INSR, FOXO1, AKT3) was greater for ENH primarily during the milk-fed period and corresponded with greater serum insulin. The greater reticuloruminal mass in calves fed ENH postweaning underscores the importance of feeding high-quality starter and indicates that fermentability of the diet, by providing metabolic fuel for ruminal epithelial cells, is a primary driver of ruminal development postweaning. From a mechanistic standpoint, the 7-fold increase in expression of the nuclear receptor PPARD (∼40-fold more abundant than PPARA) suggests a key role in controlling biological processes driving ruminal epithelial cell development. Elucidating ligands of PPARD may provide the means for nutritional regulation of rumen development.
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