Job stress in young physicians with an emphasis on the work-home interface: a nine-year, nationwide and longitudinal study of its course and predictors

Although physicians are known to experience more stress than other workers, knowledge is lacking on the course of stress from a longitudinal perspective. This study explored the course of and contributors to, different dimensions of early career job-stress among physicians by means of a nationwide mail survey, with a particular emphasis on stress relating to the work-home interference. All physicians graduating from all four Norwegian universities in 1993 / 94 (N=631), responded during their final year of medical school (N=522), during their internship (N=402), in their 4th postgraduate year (N=422), and in their 10th postgraduate year (N=390). The mean observation period was 9.2 yr (SD=0.5). The main outcomes were job stress dimensions derived from an established job stress questionnaire (Cooper / Tyssen), with emphasis placed on dimensions of the work-home interference. Stress relating to the work-home interference increased during the observation period for both genders (repeated measures: beta=0.06, p<0.05), whereas stress relating to emotional pressure, time pressure, and fear of complaints and criticism, decreased. Stress relating to the work-home interference increased during their early career, mainly due to a lack of adaptive reduction in work hours and an increased number of children. Neuroticism, conscientiousness, and lack of support from one's partner and colleagues, appeared to be predictive of this stress.     

Ultrashort intracorporeally maneuverable cryoprobes for laparoscopic renal cryoablation in the porcine model

AIM: To determine the feasibility and efficacy of laparoscopic renal cryosurgery using a novel ultrathin ultrashort intracorporeal cryoprobe in a porcine model. MATERIAL AND METHODS: Novel cryoprobes 4 cm in length and 1.5 mm in diameter were manipulated intracorporeally after insertion via a designated 15 mm laparoscopic port. Renal cryoablative lesions were induced laparoscopically in four 40 kg female piglets. We correlated between intraoperative temperature, ice ball geometry, intraoperative ultrasonographic properties, and histology. RESULTS: Laparoscopic manipulation of the cryoprobes was straightforward. No port site bleeding occurred during insertion, freezing, thawing or upon removal of the probes. The 0 degrees C, -20 degrees C, and -40 degrees C isotherms were measured at 6, 8, and 12 mm from the probe circumferentially. Ice-ball volume stabilization as determined by ultrasound occurred after 10 min of activation. Lower temperatures were reached after 10 min of probe activation as compared with 5 min (ice ball diameter 30 mm, DeltaT = 13-21 degrees C). Using a second 10-min-long freeze cycle resulted in a 14-22 degrees C lower temperature within the ice ball compared to a single cycle. Full coagulative necrosis was noted in the areas between the inserted probes with an additional 1-2 mm circumferential rim of severe tubular damage and apoptosis. CONCLUSIONS: Our novel cryoprobe can be used effectively and conveniently in laparoscopic renal cryosurgery. Considering the size of the cryogenic lesion, using a cluster of probes may be advisable.     

Establishing Laparoscopic Roux-en-Y Gastric Bypass: Perioperative Outcome and Characteristics of the Learning Curve

Background  Bariatric surgery was established at several Norwegian hospitals in 2004. This study evaluates the perioperative outcome and the learning curves for two surgeons while introducing laparoscopic Roux-en-Y gastric bypass (LRYGB). Methods  Morbidly obese patients undergoing primary LRYGB were included. Lengths of surgery and postoperative hospital stay, and 30-day rates of morbidity, reoperations, and readmissions were set as indicators of the learning curve. Learning effects were evaluated by graphical analyses and comparing the first and last 40 procedures for both surgeons. Results  The 292 included patients had a mean age of 40.0 ± 9.5 years and a mean body mass index (BMI) of 46.7 ± 5.3 kg/m². The mean length of surgery was 101 ± 55 min. Complications occurred in 43 patients (14.7%), with no conversions to open surgery in the primary procedure and no mortality. Reoperations were performed in 14 patients (4.8%), of which five patients required open surgery. The median length of stay was 3 days (range 1–77), and 19 patients (6.5%) were readmitted. High patient age, but not high BMI, was associated with an increased risk of complication. For both surgeons, lengths of surgery and hospital stay were significantly reduced (p < 0.001), leveling out after 100 procedures. Reductions in the rates of morbidity, reoperations and readmissions were not found. Conclusion  LRYGB was introduced with an acceptable morbidity rate and no mortality. Only the length of surgery and postoperative hospital stay were suitable indicators of a learning curve, which comprised about 100 cases.     

Development of a clipped single-bag with bicarbonate replacement fluid to ensure proper mixing

A clipped single-bag for bicarbonate replacement fluid was developed to ensure proper mixing before administering to the patient. Nonmixture can cause imbalances of electrolytes and pH, which is a key problem for the current double-bag type bicarbonate replacement fluid sets. To resolve this problem, this single bag properly mixes the solutions before use. The new bag consists of a clip that is placed in the middle to keep the two solutions separated and sealed. When the caregiver is ready to administer treatment, the bag is simply unfolded and the clip automatically detaches, releasing the fluids. Thereby, the bicarbonate fluids are effectively mixed. An optimal clip size with an outer diameter of 16 mm and thickness of 2 mm was determined using compression tests and drop tests. This bag may be a safer and more effective way to provide proper replacement fluid supply for both hemofiltration and hemodiafiltration.     

A systematic screening of total antioxidants in dietary plants

A predominantly plant-based diet reduces the risk for development of several chronic diseases. It is often assumed that antioxidants contribute to this protection, but results from intervention trials with single antioxidants administered as supplements quite consistently do not support any benefit. Because dietary plants contain several hundred different antioxidants, it would be useful to know the total concentration of electron-donating antioxidants (i.e., reductants) in individual items. Such data might be useful in the identification of the most beneficial dietary plants. We have assessed systematically total antioxidants in a variety of dietary plants used worldwide, including various fruits, berries, vegetables, cereals, nuts and pulses. When possible, we analyzed three or more samples of dietary plants from three different geographic regions in the world. Total antioxidants was assessed by the reduction of Fe(3+) to Fe(2+) (i.e., the FRAP assay), which occurred rapidly with all reductants with half-reaction reduction potentials above that of Fe(3+)/Fe(2+). The values, therefore, expressed the corresponding concentration of electron-donating antioxidants. Our results demonstrated that there is more than a 1000-fold difference among total antioxidants in various dietary plants. Plants that contain most antioxidants included members of several families, such as Rosaceae (dog rose, sour cherry, blackberry, strawberry, raspberry), Empetraceae (crowberry), Ericaceae (blueberry), Grossulariaceae (black currant), Juglandaceae (walnut), Asteraceae (sunflower seed), Punicaceae (pomegranate) and Zingiberaceae (ginger). In a Norwegian diet, fruits, berries and cereals contributed 43.6%, 27.1% and 11.7%, respectively, of the total intake of plant antioxidants. Vegetables contributed only 8.9%. The systematic analysis presented here will facilitate research into the nutritional role of the combined effect of antioxidants in dietary plants.     

Green energy by recoverable triple-oxide mesostructured perovskite photovoltaics

Perovskite solar cells have developed into a promising branch of renewable energy. A combination of feasible manufacturing and renewable modules can offer an attractive advancement to this field. Herein, a screen-printed three-layered all-nanoparticle network was developed as a rigid framework for a perovskite active layer. This matrix enables perovskite to percolate and form a complementary photoactive network. Two porous conductive oxide layers, separated by a porous insulator, serve as a chemically stable substrate for the cells. Cells prepared using this scaffold structure demonstrated a power conversion efficiency of 11.08% with a high open-circuit voltage of 0.988 V. Being fully oxidized, the scaffold demonstrated a striking thermal and chemical stability, allowing for the removal of the perovskite while keeping the substrate intact. The application of a new perovskite in lieu of a degraded one exhibited a full regeneration of all photovoltaic performances. Exclusive recycling of the photoactive materials from solar cells paves a path for more sustainable green energy production in the future.

Elevating world temperatures along climatic model predictions (1) hasten the need for the global economy to move toward green renewable energy production. On the photovoltaic branch, organic (2), inorganic (3, 4), and photosynthetic (5) light harvesters were investigated extensively. In recent years, organic–inorganic perovskite solar cells (PSCs) have been breaking efficiency records (6). Perovskites are a widely diverse and tunable class of materials (7), possessing high charge diffusion length characteristics under illumination. The attractive qualities and surge of development have made the PSCs, especially fully printable panels (8), prominent candidates for large-scale commercialization (9). Simultaneously, much effort has been made to stabilize perovskite''s intrinsic properties (10) through the research of different compositions and fabrication methods. These efforts include the introduction of hole conductor–free configurations (11), two-dimensional perovskite compositions (12), and, recently, the usage of methylammonium-free compounds (13). In a typical PSC structure, the perovskite layer is situated between an electron-transporting layer (ETL) on the one side and a hole-transporting material (HTM) on the other side. Traditionally, a metal contact is evaporated onto the HTM as a cathode, sealing the basic functional structure of the cell. The alignment of the electronic structure of the functional layers enables the ETL to effectively block the diffusion of holes from the perovskite and the HTM to block electrons from reaching the cathode. HTM-free configurations eliminate the HTM layer between the light absorber and the cathode and rely on the ETL alone to induce anisotropic average diffusion of the charges as a photocurrent. Since HTMs are commonly expensive and prone to degradation over time, HTM-free configurations contribute to the cells'' durability and tenability and significantly lower their cost. One such configuration utilizes a porous carbon layer as the cathode of the cell (14), allowing the perovskite precursor solution to percolate through the pores and crystalize inside the structure.Here, a triple-layered structure of sintered nanoparticles (NPs) was designed as a general scaffold for various perovskite compositions and deposition methods. The rigid and stable, screen-printed oxide nanoparticle films form layers which manifest electronic attributes similar to their building blocks. The general structure of the scaffold includes a porous electron-conducting NP layer and a porous NP cathode, separated by a porous insulating NP layer. Though the use of alternative conductive NPs is plausible, indium tin oxide (ITO) particles were chosen as the cathodic material in this work. This conductive metal oxide material can endure more extreme chemical and thermal conditions than most other nanoparticles can. The virtue of such oxides lies in their strong structure and inert chemical behavior toward oxygen and water. NPs of the closely related metal oxide fluorine-doped tin oxide (FTO) are possible candidates for the substitution of ITO as the cathodic material in the future, with economic advantages appealing for commercialization. Widely used in the field of PSCs, mesoporous TiO₂ (mpTiO₂) possesses the ability to efficiently receive and conduct electrons from the conduction band of the perovskite and thus serves as the ETL in the structure. Since charge separation in PSCs arises from light absorption in the perovskite, continuity and connectivity of the perovskite material must be maintained, along with complete insulation between the anodic and cathodic parts of the cell. Screen-printed mesoporous ZrO₂ (mpZrO₂) was used here as an ideal material choice for the insulating layer. All three mentioned layers were successively printed and sintered atop a transparent FTO-coated glass photoanode to complete a full scaffold configuration of FTO/mpTiO₂/mpZrO₂/mpITO. The perovskite solution can then be applied directly onto the cathode contact, subsequently forming a three-dimensional polycrystalline network of perovskite in the cavities between the scaffold NPs. The ITO contact provides direct electron injection to the perovskite under illumination, and at this point the cell’s full structure is complete, without the need for any additional steps. Here, the deposition of (MA_0.15FA_0.85)PbI₃ perovskite is demonstrated, along with an optical, morphological, electronic, and photovoltaic characterization of the cells. These scalable solar cells exhibited high short-circuit currents, impressive stability, and the unique possibility of recycling by removing and reapplying damaged or degraded perovskite.