Electron and Ion Transport in Lithium and Lithium-Ion Battery Negative and Positive Composite Electrodes.

Electrochemical energy storage systems, specifically lithium and lithium-ion batteries, are ubiquitous in contemporary society with the widespread deployment of portable electronic devices. Emerging storage applications such as integration of renewable energy generation and expanded adoption of electric vehicles present an array of functional demands. Critical to battery function are electron and ion transport as they determine the energy output of the battery under application conditions and what portion of the total energy contained in the battery can be utilized. This review considers electron and ion transport processes for active materials as well as positive and negative composite electrodes. Length and time scales over many orders of magnitude are relevant ranging from atomic arrangements of materials and short times for electron conduction to large format batteries and many years of operation. Characterization over this diversity of scales demands multiple methods to obtain a complete view of the transport processes involved. In addition, we offer a perspective on strategies for enabling rational design of electrodes, the role of continuum modeling, and the fundamental science needed for continued advancement of electrochemical energy storage systems with improved energy density, power, and lifetime.

Do beta-blockers reduce negative intrusive thoughts and anxiety in cancer survivors? - An emulated trial.

BACKGROUND: High rates of negative intrusive thoughts have been reported among cancer patients. Prevalent users of beta-blocker therapy have reported lower levels of cancer related intrusive thoughts than non-user. The aim of this study is to investigate if initiation of beta-blocker therapy reduces the prevalence and severity of intrusive thoughts (co-primary endpoints) and the prevalence of anxiety, depressed mood, and low quality of life (secondary endpoints) in cancer survivors. METHODS: Data on patient-reported outcomes from three cohort studies of Swedish patients diagnosed with colon, prostate or rectal cancer were combined with data on beta-blocker prescriptions retrieved from the Swedish Prescribed Drug Register. Two randomized controlled trials were emulated. Trial 1 had follow-up 1 year after diagnosis, trial 2 had follow-up 2 years after diagnosis, baseline in both trials was 12 months before follow-up. Those who initiated beta-blocker therapy between baseline and follow-up was assigned Active group, those who did not was assigned Control group. All endpoints were analysed using Bayesian ordered logistic regression. RESULTS: Trial 1 consisted of Active group, n = 59, and Control group, n = 3936. Trial 2 consisted of Active group, n = 87, and Control group, n = 3132. The majority of participants were men, 83% in trial 1 and 94% in trial 2. The prevalence and severity of intrusive thoughts were lower in the Active group in trial 1, but no significant differences between groups were found in either trial. The prevalence of depressed mood, worse quality of life and periods of anxiety were higher in the Active group in both trials with significant differences for quality of life in trial 1 and anxiety in trial 2. CONCLUSIONS: The emulated trials demonstrated no evidence of a protective effect of beta-blocker therapy against intrusive thoughts. The Active group had reduced quality of life and elevated anxiety compared to the Control group. TRIAL REGISTRATION: The three cohort studies were registered at isrctn.com/clinicaltrials.gov (ISRCTN06393679, NCT02530593 and NCT01477229).

Short-term results in a population based study indicate advantage for minimally invasive rectal cancer surgery versus open.

BACKGROUND: The aim of this study was to determine if minimally invasive surgery (MIS) for rectal cancer is non-inferior to open surgery (OPEN) regarding adequacy of cancer resection in a population based setting. METHODS: All 9,464 patients diagnosed with rectal cancer 2012-2018 who underwent curative surgery were included from the Swedish Colorectal Cancer Registry. PRIMARY OUTCOMES: Positive circumferential resection margin (CRM < 1 mm) and positive resection margin (R1). Non-inferiority margins used were 2.4% and 4%. SECONDARY OUTCOMES: 30- and 90-day mortality, clinical anastomotic leak, re-operation < 30 days, 30- and 90-day re-admission, length of stay (LOS), distal resection margin < 1 mm and < 12 resected lymph nodes. Analyses were performed by intention-to-treat using unweighted and weighted multiple regression analyses. RESULTS: The CRM was positive in 3.8% of the MIS group and 5.4% of the OPEN group, risk difference -1.6% (95% CI -1.623, -1.622). R1 was recorded in 2.8% of patients in the MIS group and in 4.4% of patients in the OPEN group, risk difference -1.6% (95% CI -1.649, -1.633). There were no differences between the groups in adjusted unweighted and weighted analyses. All analyses demonstrated decreased mortality and re-admissions at 30 and 90 days as well as shorter LOS following MIS. CONCLUSIONS: In this population based setting MIS for rectal cancer was non-inferior to OPEN regarding adequacy of cancer resection with favorable short-term outcomes.

Digital twins and Bayesian dynamic borrowing: Two recent approaches for incorporating historical control data.

Recent years have seen an increasing interest in incorporating external control data for designing and evaluating randomized clinical trials (RCT). This may decrease costs and shorten inclusion times by reducing sample sizes. For small populations, with limited recruitment, this can be especially important. Bayesian dynamic borrowing (BDB) has been a popular choice as it claims to protect against potential prior data conflict. Digital twins (DT) has recently been proposed as another method to utilize historical data. DT, also known as PROCOVA™, is based on constructing a prognostic score from historical control data, typically using machine learning. This score is included in a pre-specified ANCOVA as the primary analysis of the RCT. The promise of this idea is power increase while guaranteeing strong type 1 error control. In this paper, we apply analytic derivations and simulations to analyze and discuss examples of these two approaches. We conclude that BDB and DT, although similar in scope, have fundamental differences which need be considered in the specific application. The inflation of the type 1 error is a serious issue for BDB, while more evidence is needed of a tangible value of DT for real RCTs.

The impact of the anastomotic configuration on low anterior resection syndrome 3 years after total mesorectal excision for rectal cancer: a national cohort study.

AIM: After low anterior resection, the bowel can be anastomosed in different ways. It is not clear which configuration is optimal from a functional and complication point of view. The primary aim was to investigate the impact of the anastomotic configuration on bowel function evaluated by the low anterior resection syndrome (LARS) score. Secondarily, the impact on postoperative complications was evaluated. METHOD: All patients who had undergone low anterior resection from 2015 to 2017 were identified in the Swedish Colorectal Cancer Registry. Three years after surgery, patients were sent an extensive questionnaire and were analysed based on anastomotic configuration ('J-pouch/side-to-end anastomosis' or 'straight anastomosis'). Inverse probability weighting by propensity score was used to adjust for confounding factors. RESULTS: Among 892 patients, 574 (64%) responded, of whom 494 patients were analysed. After weighting, the anastomotic configuration had no significant impact on the LARS score (J-pouch/side-to-end OR 1.05, 95% confidence interval [CI] 0.82-1.34). The J-pouch/side-to-end anastomosis was significantly associated with overall postoperative complications (OR 1.43, 95% CI 1.06-1.95). No significant difference was seen regarding surgical complications (OR 1.14, 95% CI 0.78-1.66). CONCLUSION: This is the first study investigating the impact of the anastomotic configuration on long-term bowel function, evaluated by the LARS score, in an unselected national cohort. Our results suggested no benefit for J-pouch/side-to-end anastomosis on long-term bowel function and postoperative complication rates. The anastomotic strategy may be based upon the anatomical conditions of the patient and surgical preference.

Survival in relation to time to start of curative treatment of colon cancer: A national register-based observational noninferiority study.

AIM: There are ample discussions regarding the timing of treatment, especially in the era after Covid that caused delay to treatment. The aim of this study was to determine whether a delayed start to curative treatment, within 29-56 days after a diagnosis of colon cancer, was noninferior to starting treatment within 28 days, with regard to all-cause mortality. METHOD: This is a national register-based observational noninferiority study, with a noninferiority margin of hazard ratio (HR) 1.1, including all patients treated with curative intent for colon cancer in Sweden between 2008 and 2016. The primary outcome was all-cause mortality. Secondary outcomes were length of hospital stay, readmissions and reoperations within 1 year after surgery. Exclusion criteria were emergency surgery, disseminated disease at diagnosis, missing diagnosis date and treatment for another cancer 5 years before colon cancer diagnosis. RESULTS: A total of 20 836 individuals were included. A period of 29-56 days from diagnosis to start of curative treatment was noninferior versus starting treatment within 28 days for the primary outcome of all-cause mortality (HR 0.95, 95% CI 0.89-1.00). Starting treatment within 29-56 days was associated with a shorter length of stay (average 9.2 vs. 10 days) but a higher risk of reoperation compared to within 28 days. Post hoc analyses demonstrated that surgical modality was driving survival rather than time to treatment. Overall survival was greater after laparoscopic surgery (HR 0.78, 95% CI 0.69-0.88). CONCLUSION: For patients with colon cancer, a period of up to 56 days from diagnosis to the start of curative treatment did not lead to worse overall survival.

Functional Outcomes of Emergency Surgery for Perforated Diverticulitis, Hinchey Grade III.

BACKGROUND: Laparoscopic lavage as a treatment for perforated diverticulitis, Hinchey III, has been found safe and feasible in randomized trials. A few studies have reported functional outcomes and quality of life as secondary outcomes. This study investigated distress associated with dysfunction of the bowel or stoma, functional outcomes, and quality of life 2-3 years after surgery in a national unselected cohort. METHODS: All patients in Sweden who underwent emergency surgery for perforated diverticulitis with purulent peritonitis (2016-2018) were invited to answer a comprehensive, study-specific questionnaire 2-3 years after the index surgery. RESULTS: Out of 499 potential patients, 226 returned the questionnaire, and 209 were included in the analysis. There was no statistically significant difference between laparoscopic lavage and resection in distress associated with dysfunction of the bowel or stoma (odds ratio [OR], 1.32 [95% CI, 0.91-1.92]; p = 0.015). Bowel dysfunction measured by the LARS score was significantly higher for the lavage group (OR, 1.65 [95% CI, 1.11-2.45]), while stoma was more frequent after resection surgery (40 vs 6%). CONCLUSIONS: Patients experienced long-term distress from bodily dysfunction after emergency surgery for perforated diverticulitis regardless of the technique used. Regular follow-up could benefit these patients. TRIAL REGISTRATION: The project was registered at ClinicalTrials.gov on 2017-11-06. Identifier: NCT03332550. Acronym: LapLav.

Sick leave and predictive factors for sick leave at 12 months after breast cancer surgery in the randomized controlled physical activity trial (PhysSURG-B).

OBJECTIVE: To evaluate sick leave 12 months after breast cancer surgery, to analyze the effect of adjuvant chemotherapy and to identify predictive factors for sick leave, based on a randomized controlled trial of a non-supervised physical activity intervention (PhysSURG-B). METHODS: Sick leave days (for patients age 18-67) were collected from the Swedish Social Insurance Agency, and compared between the intervention and control arm in the trial. A random forest model was used to analyze predictive factors for sick leave, including baseline patient and tumor characteristics as well as patient-reported outcomes measuring quality of life, personality traits, pain, anxiety and depression. RESULTS: A total of 203 patients were analyzed, and when comparing intervention to control, there was no differences in sick leave days (117 vs 55 days, odds ratio 1.21; 95% CI 0.75-1.96). Adjuvant chemotherapy significantly increased days of sick leave (323 vs 42 days, odds ratio 17.3; 95% CI 9.15-34.2). Factors predicting prolonged sick leave were adjuvant chemotherapy, young age, previous mental health problems and low quality of life (measured as FACT-B score) at baseline. CONCLUSION: A non-supervised physical activity intervention had no effect on sick leave 12 months after surgery. Significantly longer sick leave was seen in patients treated by adjuvant chemotherapy. Factors predicting prolonged sick leave can be recognized at baseline and utilized when designing future interventions.

Simultaneous Elucidation of Solid and Solution Manganese Environments via Multiphase Operando Extended X-ray Absorption Fine Structure Spectroscopy in Aqueous Zn/MnO2 Batteries.

Aqueous Zn/MnO2 batteries (AZMOB) with mildly acidic electrolytes hold promise as potential green grid-level energy storage solutions for clean power generation. Mechanistic understanding is critical to advance capacity retention needed by the application but is complex due to the evolution of the cathode solid phases and the presence of dissolved manganese in the electrolyte due to a dissolution-deposition redox process. This work introduces operando multiphase extended X-ray absorption fine structure (EXAFS) analysis enabling simultaneous characterization of both aqueous and solid phases involved in the Mn redox reactions. The methodology was successfully conducted in multiple electrolytes (ZnSO4, Zn(CF3SO3)2, and Zn(CH3COO)2) revealing similar manganese coordination environments but quantitative differences in distribution of Mnn+ species in the solid and solution phases. Complementary Raman spectroscopy was utilized to identify the less crystalline Mn-containing products formed under charge at the cathodes. This was further augmented by transmission electron microscopy (TEM) to reveal the morphology and surface condition of the deposited solids. The results demonstrate an effective approach for bulk-level characterization of poorly crystalline multiphase solids while simultaneously gaining insight into the dissolved transition-metal species in solution. This work provides demonstration of a useful approach toward gaining insight into complex electrochemical mechanisms where both solid state and dissolved active materials are important contributors to redox activity.

Effect of Short-term Homebased Pre- and Postoperative Exercise on Recovery After Colorectal Cancer Surgery (PHYSSURG-C): A Randomized Clinical Trial.

OBJECTIVE: To determine the effect of a short-term, unsupervised exercise intervention before and after colorectal cancer surgery on self-assessed physical recovery. SUMMARY OF BACKGROUND DATA: Preoperative exercise interventions could help improve recovery after colorectal cancer surgery and is currently recommended. METHODS: A randomized, parallel, open-label trial in six university or regional hospitals in Sweden. Inclusion criteria were age ≥20 years and planned elective colorectal cancer surgery. Participants were randomized to either a physical activity intervention with aerobic activity and inspiratory muscle training 2 weeks pre- and 4 weeks postoperatively or usual care. The primary outcome measure was self-assessed physical recovery 4 weeks postoperatively. Analyses were performed according to intention to treat. Outcome assessors were masked regarding the intervention while both participants and physiotherapists were informed due to the nature of the intervention. RESULTS: Between January 22, 2015, and May 28, 2020, 761 participants were recruited and assigned to either intervention (I) (n = 379) or control (C) (n = 382). After exclusions 668 participants (I = 317, C = 351) were included in the primary analysis. There was no effect from the intervention on the primary outcome measure (adjusted odds ratio 0.84, 95% confidence interval 0.62-1.15) with 13% and 15% of participants feeling fully physically recovered in I and C, respectively. There were no reported adverse events. CONCLUSIONS: There was no effect from a physical activity intervention before and after colorectal cancer surgery on short-term self-assessed physical recovery. The results from this study call for reconsiderations regarding current recommendations for preoperative physical activity interventions.

Long-term survival after treatment for primary anal cancer- results from the Swedish national ANCA cohort study.

BACKGROUND: Squamous cell carcinoma of the anus is increasing in incidence but remains a rare disease with good 3- and 5-year recurrence free and overall survival rates of 63%-86%. The treatment includes chemoradiotherapy, mainly with 5-fluoruracil (5FU) and mitomycin. The aim of this study was to describe long-term (up to 9 years after treatment) oncological outcome and the types of treatments given, in a Swedish national cohort of patients diagnosed with anal cancer between 2011 and 2013. METHOD: Patients were identified in the Swedish Cancer Registry. Patients still alive were contacted and asked for consent. Clinical data were retrieved from National Patient Register at the Swedish National Board of Health and Welfare and from medical records. Unadjusted and adjusted analyses were performed for overall survival. RESULTS: Three hundred and eighty-eight patients were included in the study of which 338 patients (87%) received treatment with a curative intent. Follow up was 85 months (0-113 months) for patients treated with curative intent (information missing in one patient) 7.5 months (0-55) for patients with treated with a palliative intent. Curative treatment varied and consisted of both chemoradiotherapy and radiotherapy (46-64 Gy) alone. 5-FU, mitomycin and cisplatin were the most used chemotherapy agents. Five-year overall survival for patients treated with curative intent was 73%. In an adjusted analysis 5-FU and mitomycin is associated with a lower mortality than 5-FU and cisplatin but the association was weaker (HR 1.61 (95% CI: 0.904; 2.85) than in the unadjusted analysis. CONCLUSIONS: In this national cohort overall five-year survival was 73% for patients treated with curative intent. As reported by others our results indicate that 5-FU and mitomycin C should be the preferred chemotherapy in treatment for cure.

Multimodal electrochemistry coupled microcalorimetric and X-ray probing of the capacity fade mechanisms of Nickel rich NMC - progress and outlook.

Lithium nickel manganese cobalt oxide (NMC) is a commercially successful Li-ion battery cathode due to its high energy density; however, its delivered capacity must be intentionally limited to achieve capacity retention over extended cycling. To design next-generation NMC batteries with longer life and higher capacity the origins of high potential capacity fade must be understood. Operando hard X-ray characterization techniques are critical for this endeavor as they allow the acquisition of information about the evolution of structure, oxidation state, and coordination environment of NMC as the material (de)lithiates in a functional battery. This perspective outlines recent developments in the elucidation of capacity fade mechanisms in NMC through hard X-ray probes, surface sensitive soft X-ray characterization, and isothermal microcalorimetry. A case study on the effect of charging potential on NMC811 over extended cycling is presented to illustrate the benefits of these approaches. The results showed that charging to 4.7 V leads to higher delivered capacity, but much greater fade as compared to charging to 4.3 V. Operando XRD and SEM results indicated that particle fracture from increased structural distortions at >4.3 V was a contributor to capacity fade. Operando hard XAS revealed significant Ni and Co redox during cycling as well as a Jahn-Teller distortion at the discharged state (Ni3+); however, minimal differences were observed between the cells charged to 4.3 and 4.7 V. Additional XAS analyses using soft X-rays revealed significant surface reconstruction after cycling to 4.7 V, revealing another contribution to fade. Operando isothermal microcalorimetry (IMC) indicated that the high voltage charge to 4.7 V resulted in a doubling of the heat dissipation when compared to charging to 4.3 V. A lowered chemical-to-electrical energy conversion efficiency due to thermal energy waste was observed, providing a complementary characterization of electrochemical degradation. The work demonstrates the utility of multi-modal X-ray and microcalorimetric approaches to understand the causes of capacity fade in lithium-ion batteries with Ni-rich NMC.

Intraoperative adverse events as a risk factor for local recurrence of rectal cancer after resection surgery.

AIM: Failure to achieve a radical resection as well as intraoperative rectal perforation are important risk factors for local recurrence after rectal cancer surgery, but the importance of other intraoperative adverse events for the prognosis is unknown. The aim of this study was to assess the occurrence of intraoperative adverse events during rectal cancer surgery, and to determine whether these were associated with an increased risk of local recurrence. METHODS: A retrospective population-based cohort study was undertaken, including all patients in Region Västra Götaland, Sweden, who had undergone primary resection surgery for rectal cancer diagnosed between 2010 and 2014, registered in the Swedish Colorectal Cancer Registry. Data were retrieved from the registry and through review of the medical records. RESULTS: In total, 1208 patients were included in the study of whom 78 (6%) developed local recurrence during the follow-up period of at least 5 years. Intraoperative adverse events were common and occurred in 62/78 (79%) of patients with local recurrence compared to 604/1130 (53%) of patients without local recurrence. In multivariate analysis intraoperative adverse events were found to be an independent risk factor for local recurrence of rectal cancer, as were nonradical resection, a high pathological T stage, the presence of lymph node metastases, type of surgery and refraining from rectal washout during anterior resection and Hartmann's procedure. CONCLUSIONS: Intraoperative adverse events were found to be an independent risk factor for local recurrence of rectal cancer and could possibly be used together with other known risk factors to select patients for intensified postoperative surveillance.

Patient-reported QoL in anal cancer survivors 3 and 6 years after treatment-results from the Swedish national ANCA study.

PURPOSE: The impact of anal cancer treatment for the patients is best evaluated by the patients themselves. The purpose of this study was to investigate quality of life (QoL) in patients with anal cancer at 3 and 6 years after treatment. METHODS: A Swedish national cross-sectional prospective cohort study with patients diagnosed with anal cancer between 2011 and 2013. Patients were invited to respond to a QoL questionnaire at 3 and 6 years, with focus on bowel, urinary and sexual function, social and mental function, co-morbidity, lifestyle, daily activities, personal characteristics, and perceived QoL. It also contained questions on the severity of the symptoms regarding occurrence, frequency, and duration and the level of "bother" experienced related to functional symptoms. QoL and prevalence of bother with urinary, sexual, bowel dysfunction, and anal pain were described. The prevalence of impaired QoL was compared with a healthy reference population. The association between QoL and experiencing bother was quantified by regression models. RESULTS: From an original cohort of 464 patients with anal cancer, 264 (57%) were alive and contacted at 3 years and 230 (50%) at 6 years. One hundred ninety-five (74%) patients responded to the 3-year and 152 (66%) to the 6-year questionnaire. Sixty percent reported low QoL at both 3 and 6 years. Impaired QoL was more prevalent among patients with major bother due to bowel dysfunction (at 3 years RR 1.42, 95% CI (1.06-1.9) p-value 0.020, at 6 years RR 1.52, 95% CI (1.03-2.24) p-value 0.034) and urinary dysfunction (at 6 years RR 1.44, 95% CI (1.08-1.91) p-value 0.013). There was a tendency to a positive relationship between the number of bodily functions causing bother and risk for impaired QoL. CONCLUSION: Patients treated for anal cancer reported bother regarding several bodily functions as well as poor QoL both at 3 and 6 years without much improvement. Bother was also associated with low QoL indicating that function-related bother should be addressed.

Preoperative Group Consultation Prior to Surgery for Colorectal Cancer-an Explorative Study of a New Patient Education Method.

Patients with colorectal cancer may lack information about the disease and treatment. In 2017, a group consultation before start of surgery was introduced at a university hospital in western Sweden to inform about the disease, treatment, and ongoing scientific studies. The primary aim of this study was to explore the experience of the patients attending the group consultation. Based on semi-structured interviews with patients with colorectal cancer, a questionnaire was constructed and administered to patients, both those attending and those not attending the group consultation. In total, 124 patients were included and the response rate was 86%. A majority of patients attending the group consultation would recommend it to someone else with the same illness. Of the patients attending the group consultation, 81% (30/37) patients agreed, fully or partially, that attending the group consultation had increased their sense of control and 89% (33/37) that the information they received at the group consultation increased their feeling of participation in the treatment. Preoperative group consultation is a feasible modality for informing and discussing the upcoming treatment for colorectal cancer with the patients, and the patients who attended the group setting appreciated it. Attending the group consultation increased the patients' feeling of active participation in their treatment and their sense of control, which could possibly both improve their experience of their illness and facilitate recovery. CLINICALTRIALS.GOV IDENTIFIER: NCT03888313.

Methods of Colostomy Construction: No Effect on Parastomal Hernia Rate: Results from Stoma-const-A Randomized Controlled Trial.

OBJECTIVE: The primary objective of this trial was to compare the parastomal hernia rates 1 year after the construction of an end colostomy by 3 surgical techniques: cruciate incision, circular incision in the fascia and using prophylactic mesh. Secondary objectives were evaluation of postoperative complications, readmissions/reoperations, and risk factors for parastomal hernia. SUMMARY OF BACKGROUND DATA: Colostomy construction techniques have been explored with the aim to improve function and reduce stoma complications, but parastomal herniation is frequent with an incidence of approximately 50%. METHODS: A randomized, multicenter trial was performed in 3 hospitals in Sweden and Denmark; all patients scheduled to receive an end colostomy were asked to participate. Parastomal hernia within 12 months was determined by computed tomography of the abdomen in prone position and by clinical assessment. Complications, readmissions, reoperations, and risk factors were also assessed. RESULTS: Two hundred nine patients were randomized to 1 of the 3 arms of the study. Patient demographics were similar in all 3 groups. Assessment of parastomal hernia was possible in 185 patients. The risk ratio (95% confidence interval) for parastomal hernia was 1.25 (0.83; 1.88), and 1.22 (0.81; 1.84) between cruciate versus circular and cruciate versus mesh groups, respectively. There were no statistically significant differences between the groups with regard to parastomal hernia rate. Age and body mass index were found to be associated with development of a parastomal hernia. CONCLUSION: We found no significant differences in the rates of parastomal hernia within 12 months of index surgery between the 3 surgical techniques of colostomy construction.

Local and Bulk Probe of Vanadium-Substituted α-Manganese Oxide (α-KxVyMn8-yO16) Lithium Electrochemistry.

A series of V-substituted α-MnO2 (KxMn8-yVyO16·nH2O, y = 0, 0.2, 0.34, 0.75) samples were successfully synthesized without crystalline or amorphous impurities, as evidenced by X-ray diffraction (XRD) and Raman spectroscopy. Transmission electron microscopy (TEM) revealed a morphological evolution from nanorods to nanoplatelets as V-substitution increased, while electron-energy loss spectroscopy (EELS) confirmed uniform distribution of vanadium within the materials. Rietveld refinement of synchrotron XRD showed an increase in bond lengths and a larger range of bond angles with increasing V-substitution. X-ray absorption spectroscopy (XAS) of the as-prepared materials revealed the V valence to be >4+ and the Mn valence to decrease with increasing V content. Upon electrochemical lithiation, increasing amounts of V were found to preserve the Mn-Mnedge relationship at higher depths of discharge, indicating enhanced structural stability. Electrochemical testing showed the y = 0.75 V-substituted sample to deliver the highest capacity and capacity retention after 50 cycles. The experimental findings were consistent with the predictions of density functional theory (DFT), where the V centers impart structural stability to the manganese oxide framework upon lithiation. The enhanced electrochemistry of the y = 0.75 V-substituted sample is also attributed to its smaller crystallite size in the form of a nanoplatelet morphology, which promotes facile ion access via reduced Li-ion diffusion path lengths.

Structural and electrochemical investigation of crystallite size controlled zinc ferrite (ZnFe2O4).

Zinc ferrite, ZnFe2O4(ZFO), is a promising electrode material for next generation Li-ion batteries because of its high theoretical capacity and low environmental impact. In this report, synthetic control of crystallite size from the nanometer to submicron scale enabled probing of the relationships between ZFO size and electrochemical behavior. A facile two-step coprecipitation and annealing preparation method was used to prepare ZFO with controlled sizes ranging ∼9 to >200 nm. Complementary synchrotron and electron microscopy techniques were used to characterize the series of materials. Increasing the annealing temperature increased crystallinity and decreased microstrain, while local structural ordering was maintained independent of crystallite size. Electrochemical characterization revealed that the smaller sized materials delivered higher capacities during initial lithiation. Larger sized particles exhibited a lack of distinct electrochemical signatures above 1.0 V, suggesting that the longer diffusion length associated with greater crystallite size causes the lithiation process to proceed via non discrete lithium insertion, cation migration, and conversion processes. Notably, larger particles exhibited enhanced electrochemical reversibility over 50 cycles, with capacity retention improving from <20% to >40% at C/2 cycling rate. This intriguing result was probed through x-ray absorption spectroscopy (XAS) and x-ray photoelectron spectroscopy (XPS) measurements of the cycled electrodes. XAS revealed that the larger crystallite size materials do not completely convert to Fe0during the first lithiation and that independent of size, delithiation results in the formation of nanocrystalline FeO and ZnO phases rather than ZnFe2O4. After 20 cycles, the larger crystallites showed reversibility between partially oxidized FeO in the charged state and Fe0in the discharged state, while the smaller crystallite size material was electrochemically inactive as Fe0. XPS analysis revealed more significant solid electrolyte interphase (SEI) formation on the cycled electrodes utilizing ZFO with smaller crystallite size. This finding suggests that excessive SEI buildup on the smaller sized, higher surface area ZFO particles contributes to their reduced electrochemical reversibility relative to the larger crystallite size materials.

Stoma-related complications: a report from the Stoma-Const randomized controlled trial.

AIM: The impact of construction techniques on the development of stoma complications is partly undiscovered. The aim of this paper was to report and analyse the impact of the three surgical techniques in a randomized controlled trial Stoma-Const on stoma-related complications as well as identifying risk factors and patient-reported stoma function as a planned secondary analysis. METHODS: This was a randomized, multicenter trial where all patients scheduled to receive an end colostomy were invited to participate. Patients were randomized to one of three techniques for stoma construction; cruciate fascial incision, circular incision or prophylactic mesh. Stoma complications were assessed by a surgeon and stoma care nurses within 1 year postoperatively. RESULTS: Two hundred and nine patients were randomized. Patient demographics were similar in all three groups. Data on stoma-related complications were available for analysis in 201 patients. A total of 127 patients (63%) developed some type of stoma complication within 1 year after surgery. The risk ratio (95% CI) for stoma complications was 0.93 (0.73; 1.2) between cruciate vs. circular incision groups and 1.02 (0.78; 1.34) between cruciate vs. mesh groups. There were no statistically significant differences between the groups regarding parastomal hernia rate and no risk factors could be identified. CONCLUSION: This randomized trial confirmed a high prevalence of stoma-related complications but could not identify an impact of surgical technique or identify modifiable risk factors for stoma-related complications.

Predicting life with a permanent end colostomy: A prospective study on function, bother and acceptance.

AIM: The factors that influence a patient's experience of a colostomy are not known. The aim of this study was to characterise stoma function, stoma-related bother and acceptance among patients operated for rectal cancer and to investigate if there were any preoperative personal factors with predictive impact on long-term stoma-related bother. METHODS: The QoLiRECT (Quality of Life in RECTal cancer) study is a prospective multicentre study of patients with rectal cancer. This was a subgroup analysis of patients with a permanent colostomy with a 2-year follow-up. Penalised regression models with shrinkage estimation were used to predict the 1-and 2-year bother using baseline data. The predictive value and the importance of the included variables were evaluated using bootstrap resampling techniques. RESULTS: A total of 379 patients were included. Overall stoma acceptance was high and a majority of patients were not bothered by their stoma; 77% and 83% at 1 and 2 years, respectively. The subgroup of patients with stoma-related bother had a high prevalence of difficulties, especially fear of leakage, and a low stoma acceptance in daily life. Both clinical and personal factors were associated with stoma-related bother. The most important factors were quality of life and physical health, but the prediction accuracy was low. CONCLUSIONS: Stoma-related bother was associated with overall stoma dysfunction. As stoma-related bother is a multifactorial problem, it was not possible to predict which patients will experience stoma-related bother. It is therefore of importance to prevent stoma-related symptoms and optimise stoma function to reduce long-term bother and increase stoma acceptance.