A sustainable hydrometallurgical strategy for recycling efficiently platinum from spent reforming petroleum catalyst.

Platinum (Pt) is one of the most precious metals with a variety of unique industrial applications, particularly in catalytic reactions, being its recovery, after use, essential. Therefore, this work proposes a simplified hydrometallurgical strategy to recover Pt efficiently from the original (no milling) spent petrochemical Pt catalyst using an economical and environmentally sustainable process. To that end, the effectiveness of a two-step workflow constituted by one microwave-assisted leaching step using a mixture of hydrochloric acid (HCl) and hydrogen peroxide (H2O2) followed by one ion-exchange purification step was developed and optimized. It was found that complete dissolution of Pt plus aluminum (Al) and iron (Fe) from the roasted original size catalyst was achieved after microwave-assisted leaching with 25% (v/v) HCl and 2% (v/v) H2O2 during 2 cycles of 60 s. Furthermore, a strong anionic exchange (Purogold™ A194) resin used for subsequent selective purification of Pt from Al and Fe was capable of effective separation of the metals: Pt in the eluate presented a purity of 98.1%, while Al, in the raffinate, presented a purity of 99.8%. In summation, it can be concluded that the overall process is a potentially good addition to a more circular economy as it manages to recover high-quality Pt for being reused as well as other by-products, whilst minimizing the consume of reagents, leaching time (and, thus, energy), and environmental impacts.

[Knowledge and attitude of oral care providers in the Netherlands on skin lesions]. / Kennis en attitude van mondzorgverleners over huidafwijkingen.

To gain insight into the current knowledge of oral care providers in the Netherlands on facial skin lesions, a survey was distributed to 7,670 oral care providers. Their knowledge was tested by means of 4 multiple-choice questions and on the basis of 5 cases. The survey was completed in full by 90 respondents. The median age was 50.3 years and 62.2% were female. During dental check-ups, 55.6% always examined the face and 41.1% sometimes did so. Compared to the group 41 years old and older, the group 21-40 years of age alerted their patients more often to skin lesions (p = 0.017), was more afraid a specialist would find the referral useless (p < 0.001) and was more in need of a guideline (p = 0.049). The respondents scored 1.90 out of 4 correct answers to the knowledge questions. On the case studies, they scored 1.46 out of 5 for the correct diagnosis, 3.48 out of 5 for the correct choice of policy and 1.01 out of 5 for the combination correct diagnosis and correct policy. The total score was 2.91 out of 9. The results indicate that knowledge on aspects of skin lesions is limited and additional training and the availability of a guideline are necessary.

Whole-genome and transcriptome analysis enhances precision cancer treatment options.

BACKGROUND: Recent advances are enabling delivery of precision genomic medicine to cancer clinics. While the majority of approaches profile panels of selected genes or hotspot regions, comprehensive data provided by whole-genome and transcriptome sequencing and analysis (WGTA) present an opportunity to align a much larger proportion of patients to therapies. PATIENTS AND METHODS: Samples from 570 patients with advanced or metastatic cancer of diverse types enrolled in the Personalized OncoGenomics (POG) program underwent WGTA. DNA-based data, including mutations, copy number and mutation signatures, were combined with RNA-based data, including gene expression and fusions, to generate comprehensive WGTA profiles. A multidisciplinary molecular tumour board used WGTA profiles to identify and prioritize clinically actionable alterations and inform therapy. Patient responses to WGTA-informed therapies were collected. RESULTS: Clinically actionable targets were identified for 83% of patients, of which 37% of patients received WGTA-informed treatments. RNA expression data were particularly informative, contributing to 67% of WGTA-informed treatments; 25% of treatments were informed by RNA expression alone. Of a total 248 WGTA-informed treatments, 46% resulted in clinical benefit. RNA expression data were comparable to DNA-based mutation and copy number data in aligning to clinically beneficial treatments. Genome signatures also guided therapeutics including platinum, poly-ADP ribose polymerase inhibitors and immunotherapies. Patients accessed WGTA-informed treatments through clinical trials (19%), off-label use (35%) and as standard therapies (46%) including those which would not otherwise have been the next choice of therapy, demonstrating the utility of genomic information to direct use of chemotherapies as well as targeted therapies. CONCLUSIONS: Integrating RNA expression and genome data illuminated treatment options that resulted in 46% of treated patients experiencing positive clinical benefit, supporting the use of comprehensive WGTA profiling in clinical cancer care.

Physician burnout, a new term, a well-known concept in the medieval era: a thematic review of Ruhawi's Adab al-Tabib.

In 1974, Herbert Freudenberger introduced the phrase 'Burnout in Healing Professional Workers'. Despite the existence of numerous investigations on physician burnout, only a few studies on its historical aspects can be found. This is the first research to present historical evidence on 'physician burnout' as pointed out in the book 'Adab al-Tabib' written by Ruhawi (9th century AD). He is shown to have an understanding of this concept by talking about job stress in his book, although he offers no exact equivalent definition for this state. In fact, finding an equivalent term to 20th century burnout in a book written a thousand years ago is almost impossible. Most interestingly, the same preventive strategies for physician burnout and its causes as those scientifically discovered in recent years can be evidenced to have been introduced by Ruhawi. Hence, 'Adab al-Tabib' is an outstanding work on physician burnout in the medieval era.

Ligand stabilization and effect on unfolding by polymorphism in human flavin-containing monooxygenase 3.

Pharmacogenomics is a powerful tool to prevent adverse reactions caused by different response of individuals to drug administration. Single nucleotide polymorphisms (SNPs) represent up to 90% of genetic variations among individuals. Drug metabolizing enzymes are highly polymorphic therefore the kinetic parameters of their catalytic reactions can be significantly influenced. This work reports on the unfolding process of a phase I drug metabolizing enzyme, human flavin-containing monooxygenase 3 (hFMO3) and its single nucleotide polymorphic variants (SNPs) V257M, E158K and E308G. Differential scanning calorimetry (DSC) indicates that the thermal denaturation of the enzyme is irreversible. The melting temperature (Tm) for the (Wild Type) WT and its polymorphic variants is found to be in a range from 46 °C to 50 °C. Also the activation energies of unfolding (Ea) show no significant differences among all proteins investigated (290-328 KJ/mol), except for the E308G variant that showed a significantly higher Ea of 412 KJ/mol. The presence of the bound NADP+ cofactor is found to stabilize all the variants by shifting the main Tm by 4-5 °C for all the proteins, exception made for E308G where no changes are observed. Isothermal titration calorimetry (ITC) was used to characterize the interaction of the protein with NADP+ in terms of dissociation constant (Kd), enthalpy (ΔH) and entropy (ΔS). Kd values of 1.6 and 0.7 µM, ΔH of -13.9 Kcal/mol and -16.8 Kcal/mol, ΔS of -20.5 cal/mol/deg, and -28.5 cal/mol/deg were found for V257M and E158K respectively. E308G was found to be unable to bind the NADP+ cofactor, a result that is in line with the Tm results. Circular dichroism also confirmed an overall lower stability of E308G, while NADP+ was found to give a strong positive shift of the Tm stabilizing the structure of E158K (46.2 to 50.6 °C). Previous data highlighted significant differences in terms of activity among the SNPs of hFMO3. In this work a minor impact of the SNPs was found on the stability of the enzyme in the ligand free form, except for E308G, whereas the binding of NADP+ reveals major differences among WT and polymorphic variants that are all measurable in terms of heat capacity, enthalpy and secondary structure content. These data provide the first direct evidence of ligand stabilization effects on hFMO3 that can explain the differences observed in catalytic efficiencies and serve as the starting point for the development of inhibitors of this enzyme.

A critical updated review of the hydrometallurgical routes for recycling zinc and manganese from spent zinc-based batteries.

This review paper aims to present and analyse data from the most recent literature (between 2007 and 2019) published on the topic of manganese (Mn) and zinc (Zn) recovery from zinc-based spent batteries through hydrometallurgical methods. In a first attempt, a detailed comparative assessment of the metals leaching performance (as well as the experimental variables that influence its performance) reported in the various studies with strong acid or bases, potentially supplemented by complexing or reducing agents, as well as the reactions involved, are reviewed and discussed. All data point out that the use of a reductant is needed to fully solubilize Mn from spent batteries during the leaching process. Comparison of the data seem to indicate that most reductants have similar performance and, therefore, the choice of a reductant should be focused on low cost or even waste materials. In a second attempt, the separative processes mostly described in the literature to recover Mn and Zn from leachates are reviewed emphasizing the strengths and weaknesses of each technique. Solvent extraction is the most widely tested process for this aim. A thorough comparison of existing data indicates that, in general, neutral extractants have higher potential for selective separation of Zn and Mn. Furthermore, although chemical precipitation is a simple process, low pure final metal hydroxide products are expected to be achieved when alkaline precipitation is implemented comparatively to the Mn oxidative precipitation where Mn can be recovered selectively as a solid of manganese (IV) oxide.

Does behavioural inhibition system dysfunction contribute to Attention Deficit Hyperactivity Disorder?

The Reinforcement Sensitivity Theory of Personality has as its main foundation a Behavioural Inhibition System (BIS), defined by anxiolytic drugs, in which high trait sensitivity should lead to internalising, anxiety, disorders. Conversely, it has been suggested that low BIS sensitivity would be a characteristic of externalising disorders. BIS output should lead to increased arousal and attention as well as behavioural inhibition. Here, therefore, we tested whether an externalising disorder, Attention Deficit Hyperactivity Disorder (ADHD), involves low BIS sensitivity. Goal-Conflict-Specific Rhythmicity (GCSR) in an auditory Stop Signal Task is a right frontal EEG biomarker of BIS function. We assessed children diagnosed with ADHD-I (inattentive) or ADHD-C (combined) and healthy control groups for GCSR in: a) an initial smaller study in Dunedin, New Zealand (population ~120,000: 15 control, 10 ADHD-I, 10 ADHD-C); and b) a main larger one in Tehran, Iran (population ~9 [city]-16 [metropolis] million: 27 control, 18 ADHD-I, 21 ADHD-C). GCSR was clear in controls (particularly at 6-7 Hz) and in ADHD-C (particularly at 8-9 Hz) but was reduced in ADHD-I. Reduced attention and arousal in ADHD-I could be due, in part, to BIS dysfunction. However, hyperactivity and impulsivity in ADHD-C are unlikely to reflect reduced BIS activity. Increased GCSR frequency in ADHD-C may be due to increased input to the BIS. BIS dysfunction may contribute to some aspects of ADHD (and potentially other externalising disorders) and to some differences between the ADHD subtypes but other prefrontal systems (and, e.g. dopamine) are also important.

Prediction of Post Operative Complication in Patients with Valvular Heart Surgery Based on O2 Challenge Test and A-A Gradient.

Patients with valvular heart diseases may have more physiological lung derangements and therefore at current study we studied correlation of O2 challenge, A-AG tests and spirometry values of patients who underwent valve surgery on post op respiratory complications. METHOD: 180 adult patients undergoing non-emergency cardiac valvular surgery were studied. On operating room all patients had arterial blood gas profile (ABG) at room air, 20 minutes after putting on ventilator with 100% O2, and pump oxygenator. Pulmonary function tests, alveolar Oxygen Pressure, mean Arterial pressure of carbon dioxide and alveolar -arterial gradients measured. RESULTS: FEV1, FVC and FEV1/FVC%, pressure of arterial Blood Gasses (O2 and CO2) with fraction of inspired oxygen of 100% and air (PO2-100 and PO2-air), were significantly different between patients with POPC and patients without POPC (p-value <0.05). Indeed PO2-100 and PO2-air were significantly lower in patients with POPC. A-AG100 (p-value: 0.02) and A -AG21 (p-value: 0.02) were significantly higher in patients with POPC in comparison with patients without POPC. The AUC of A-AG100 for predicting POPC was 0.59 (95% confidence interval (CI) 0.51-0.67). The optimal cut point of A-AG100 was 311 and showed evidence of high relatively sensitivity of 80% and a negative predictive value of 61%. CONCLUSION: Valvular heart surgery still has significant post op complication and mortality. There is significant correlation between A-AG100, A-AG21 percent, PaO2100, and FEV1/FVC with post op complications in these patients. We recommend measurement of these values in pre op evaluation of patient who need cardiac surgery.

Tournament ABC analysis of the western Palaearctic population history of an oak gall wasp, Synergus umbraculus.

Approximate Bayesian computation (ABC) is a powerful and widely used approach in inference of population history. However, the computational effort required to discriminate among alternative historical scenarios often limits the set that is compared to those considered more likely a priori. While often justifiable, this approach will fail to consider unexpected but well-supported population histories. We used a hierarchical tournament approach, in which subsets of scenarios are compared in a first round of ABC analyses and the winners are compared in a second analysis, to reconstruct the population history of an oak gall wasp, Synergus umbraculus (Hymenoptera, Cynipidae) across the Western Palaearctic. We used 4,233 bp of sequence data across seven loci to explore the relationships between four putative Pleistocene refuge populations in Iberia, Italy, the Balkans and Western Asia. We compared support for 148 alternative scenarios in eight pools, each pool comprising all possible rearrangements of four populations over a given topology of relationships, with or without founding of one population by admixture and with or without an unsampled "ghost" population. We found very little support for the directional "out of the east" scenario previously inferred for other gall wasp community members. Instead, the best-supported models identified Iberia as the first-regional population to diverge from the others in the late Pleistocene, followed by divergence between the Balkans and Western Asia, and founding of the Italian population through late Pleistocene admixture from Iberia and the Balkans. We compare these results with what is known for other members of the oak gall community, and consider the strengths and weaknesses of using a tournament approach to explore phylogeographic model space.

Health risk assessment of exposure to the Middle-Eastern Dust storms in the Iranian megacity of Kermanshah.

OBJECTIVE: This study assessed the effects of particulate matter (PM), equal or less than 10 µm in aerodynamic diameter (PM10), from the Middle-Eastern Dust events on public health in the megacity of Kermanshah (Iran). STUDY DESIGN: This study used epidemiological modeling and monitored ambient air quality data to estimate the potential PM10 impacts on public health. METHODS: The AirQ2.2.3 model was used to calculate mortality and morbidity attributed to PM10 as representative of dust events. Using Visual Basic for Applications, the programming language of Excel software, hourly PM10 concentrations obtained from the local agency were processed to prepare input files for the AirQ2.2.3 model. RESULTS: Using baseline incidence, defined by the World Health Organization, the number of estimated excess cases for respiratory mortality, hospital admissions for chronic obstructive pulmonary disease, for respiratory diseases, and for cardiovascular diseases were 37, 39, 476, and 184 persons, respectively, from 21st March, 2014 to 20th March, 2015. Furthermore, 92% of mortality and morbidity cases occurred in days with PM10 concentrations lower than 150 µg/m3. The highest percentage of person-days occurred for daily concentrations range of 100-109 µg/m3, causing the maximum health end-points among the citizens of Kermanshah. CONCLUSIONS: Calculating the number of cumulative excess cases for mortality or morbidity attributed to PM10 provides a good tool for decision and policy-makers in the field of health care to compensate their shortcomings particularly at hospital and healthcare centers for combating dust storms. To diminish these effects, several immediate actions should be managed in the governmental scale to control dust such as spreading mulch and planting new species that are compatible to arid area.

Biodesulphurization of gasoline by Rhodococcus erythropolis supported on polyvinyl alcohol.

A new biodesulphurization (BDS) method has been considered using Rhodococcus erythropolis supported on polyvinyl alcohol (PVA) for BDS of thiophene as a gasoline sulphur model compound in n-hexane as the solvent, subsequently this biocatalyst has been applied to BDS of gasoline samples. The obtained results according to UV-Spectrophotometer analysis at 240 nm showed that 97·41% of thiophene at the optimum condition of primary concentration 80 mg l-1 , pH = 7, by 0·1 g of biocatalyst in 30°C and after 20 h of contact time has been degraded. These optimum conditions have been applied to gasoline BDS and the biodegradation of gasoline thiophenic compounds have been investigated by gas chromatography-mass spectrometry (GC-MS). According to GC-MS, thiophene and its 2-methyl, 3-methyl and 2- ethyl derivatives had acceptable biodegradation efficiencies of about 26·67, 21·03, 23·62% respectively. Also, benzothiophene that has been detected in a gasoline sample had 38·89% biodegradation efficiency at optimum conditions, so biomodification of PVA by R. erythropolis produces biocatalysts with an active metabolism that facilitates the interaction of bacterial strain with gasoline thiophenic compounds. The morphology and surface functional groups of supported R. erythropolis on PVA have been investigated by scanning electron microscope (SEM) and FT-IR spectroscopy respectively. SEM images suggest some regular layered shape for the supported bacteria. FT-IR spectra indicate a desirable interaction between bacterial cells and polymer supports. Also, the recovery of biocatalyst has been investigated and after three times of using in BDS activity, its biocatalytic ability had no significant decreases. SIGNIFICANCE AND IMPACT OF THE STUDY: The biomodification of polyvinyl alcohol by Rhodococcus erythropolis described herein produces a new biocatalyst which can be used for significantly reducing the thiophenic compounds of gasoline and other fossil fuels. The immobilization process is to increase the biodegradation efficiency of cells and accelerating the biodesulphurization process.

Control of spontaneous emission of quantum dots using correlated effects of metal oxides and dielectric materials.

We study the emission dynamics of semiconductor quantum dots in the presence of the correlated impact of metal oxides and dielectric materials. For this we used layered material structures consisting of a base substrate, a dielectric layer, and an ultrathin layer of a metal oxide. After depositing colloidal CdSe/ZnS quantum dots on the top of the metal oxide, we used spectral and time-resolved techniques to show that, depending on the type and thickness of the dielectric material, the metal oxide can characteristically change the interplay between intrinsic excitons, defect states, and the environment, offering new material properties. Our results show that aluminum oxide, in particular, can strongly change the impact of amorphous silicon on the emission dynamics of quantum dots by balancing the intrinsic near band emission and fast trapping of carriers. In such a system the silicon/aluminum oxide charge barrier can lead to large variation of the radiative lifetime of quantum dots and control of the photo-ejection rate of electrons in quantum dots. The results provide unique techniques to investigate and modify physical properties of dielectrics and manage optical and electrical properties of quantum dots.

Effect of chamber characteristics, loading and analysis time on motility and kinetic variables analysed with the CASA-mot system in goat sperm.

Several factors unrelated to the semen samples could be influencing in the sperm motility analysis. The aim of the present research was to study the effect of four chambers with different characteristics, namely; slide-coverslip, Spermtrack, ISAS D4C10, and ISAS D4C20 on the sperm motility. The filling procedure (drop or capillarity) and analysis time (0, 120 and 240s), depth of chamber (10 or 20µm) and field on motility variables were analysed by use of the CASA-mot system in goat sperm. Use of the drop-filling chambers resulted in greater values than capillarity-filling chambers for all sperm motility and kinetic variables, except for LIN (64.5% compared with 56.3% of motility for drop- and capillarity-filling chambers respectively, P<0.05). There were no significant differences in total sperm motility between different chamber depths, however, use of the 20µm-chambers resulted in greater sperm progressive motility rate, VSL and LIN, and less VCL and VAP than chambers with a lesser depth. There was less sperm motility and lesser values for kinetic variables as time that elapsed increased between sample loading and sperm evaluation. For sperm motility, use of droplet-loaded chambers resulted in similar values of MOT in all microscopic fields, but sperm motility assessed in capillarity-loaded chambers was less in the central fields than in the outermost microscopic fields. For goats, it is recommended that sperm motility be analysed using the CASA-mot system with a drop-loaded chamber within 2min after filling the chamber.

Selective leaching of Zn from spent alkaline batteries using environmentally friendly approaches.

The main aim of this work was to evaluate the possibility of using microwave or ultrasound to assist the efficient and selective leaching of Zn from spent alkaline batteries and compare the results with those obtained using the conventional method. Two different strategies were applied: acid leaching of a washed residue and alkaline leaching of the original residue. In both (acid and alkaline) approaches, the use of microwave- or ultrasound-assisted leaching increased the extraction of Zn compared with the best results obtained using conventional leaching [acid leaching (1.5mol/L H2SO4, 3h, 80°C), 90% of Zn extracted; alkaline leaching (6mol/L NaOH, 3h, 80°C), 42% of Zn extracted]. With acid leaching, 94% of the Zn was extracted using microwave-assisted leaching (1 cycle, 30s, 1mol/L H2SO4), and 92% of the Zn was extracted using ultrasound-assisted leaching (2min, 0.1p, 20% amplitude, 1mol/L H2SO4). Ultrasound-assisted leaching resulted in a more selective (Zn/Mn ratio of 5.1) Zn extraction than microwave-assisted leaching (Zn/Mn ratio of 3.5); both processes generated a concentrated Zn solution (⩾18.7g/L) with a purity (83.3% and 77.7%, respectively) that was suitable for electrowinning. With alkaline leaching, microwave- (1 cycle, 3 min, 4mol/L NaOH) and ultrasound-assisted (14min, 0.1p, 20% amplitude, 4mol/L NaOH) leaching extracted about 80% of the Zn and less than 0.01% of the Mn, which resulted in lesser concentrated Zn solutions (approximately 16.5g/L) but with high purity (>99.5%) that was suitable for the recovery of Zn by precipitation. The microwave- and ultrasound-assisted leaching strategies used in this work proved to be efficient and environmentally-friendly approaches for the extraction of Zn from spent alkaline residues since a concentrated Zn solution with adequate purity for subsequent Zn recovery was obtained using significantly decreased leaching times and concentrations of chemicals.

Long-term outcomes after adjuvant treatment of sequential versus combination docetaxel with doxorubicin and cyclophosphamide in node-positive breast cancer: BCIRG-005 randomized trial.

BACKGROUND: The optimal regimen for adjuvant breast cancer chemotherapy is undefined. We compared sequential to concurrent combination of doxorubicin and cyclophosphamide with docetaxel chemotherapy in women with node-positive non-metastatic breast cancer. We report the final, 10-year analysis of disease-free survival (DFS), overall survival (OS), and long-term safety. PATIENTS AND METHODS: A total of 3298 women with HER2 nonamplified breast cancer were randomized to doxorubicin and cyclophosphamide every 3 weeks for four cycles followed by docetaxel (AC → T) every 3 weeks for four cycles or docetaxel, doxorubicin, and cyclophosphamide (TAC) every 3 weeks for six cycles. The patients received standard radiotherapy and endocrine therapy and were followed up for 10 years with annual clinical evaluation and mammography. RESULTS: The 10-year DFS rates were 66.5% in the AC → T arm and 66.3% in the TAC arm (P = 0.749). OS was 79.9% in the AC → T arm and 78.9% in the TAC arm (P = 0.506). TAC was associated with higher rates of febrile neutropenia, although G-CSF primary prophylaxis greatly reduced this risk. AC → T was associated with a higher rate of myalgia, hand-foot syndrome, fluid retention, and sensory neuropathy. CONCLUSION: This 10-year analysis of the BCIRG-005 trial confirmed that the efficacy of TAC was not superior to AC → T in women with node-positive early breast cancer. The toxicity profiles differ between arms and were consistent with previous reports. The TAC regimen with G-CSF support provides shorter adjuvant treatment duration with less toxicity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT00312208.

Interactions between Metopolophium festucae cerealium (Hemiptera: Aphididae) and Barley yellow dwarf virus (BYDV-PAV).

Interactions between an invasive aphid, Metopolophium festucae (Theobald) subsp. cerealium, and Barley yellow dwarf virus (BYDV-PAV) were studied under laboratory conditions. M. festucae cerealium is an economic pest of wheat and barley that has recently been found in high population densities in wheat in the Pacific Northwest of the United States. BYDV-PAV is the most prevalent and injurious species of BYDV worldwide and in the Pacific Northwest. Although M. festucae sensu stricto (Theobald 1917) has been reported previously as a vector of some BYDV isolates, there is no confirmed transmission of BYDV by M. festucae cerealium. Two experiments examined the ability of M. festucae cerealium to transmit BYDV-PAV. The first used single aphids caged to indicator plants of a BYDV-susceptible winter wheat cultivar and the second used multiple aphids on each test plant. M. festucae cerealium did not transmit BYDV-PAV in either experiment, whereas transmission by a known BYDV vector, Rhopalosiphum padi L., was consistently high (≥ 93%). A third experiment compared the intrinsic growth rate, days until first reproduction and daily reproduction by M. festucae cerealium on sham-inoculated and BYDV-PAV-infected wheat, but detected no differences. The findings are reviewed in light published data on M. festucae species, BYDV transmission, and the potential pest status of this new invading aphid.

Prostatectomy at high-volume centers improves outcomes and lowers the costs of care for prostate cancer.

BACKGROUND: High-volume surgeons with ⩾250 radical prostatectomies provide superior oncological outcomes as evidenced by a lower rate of PSA recurrence (PSAR). The financial benefits of performing prostatectomies at high-volume centers (HVC) are unexplored. METHODS: A base case--referent scenario--where the share of prostatectomies at high- and low-volume centers were evenly divided at 50% was defined. Additional scenarios with increasing shares of prostatectomies at HVC with 10% increments were also modeled. Using a lower probability of PSAR as the only advantage of more experienced surgeons, the savings that would result from fewer recurrences, avoidance of salvage radiation therapy (SRT) and management of fewer men with metastatic cancer were calculated. RESULTS: The savings associated with performing 80% of radical prostatectomy at HVC were $177, $357 and $559 per prostatectomy at 5, 10 and 20 years, respectively. These savings would offset referral costs of up to $1833 per prostatectomy referral at no additional total societal costs. Given the longer average biochemical failure-free survival with prostatectomies at HVC, referral costs of more than $1833 may be cost effective. CONCLUSIONS: Under the conservative assumption of accounting for lower rates of PSAR as the only benefit of surgery in an HVC, performing prostatectomies at an HVC was associated with savings that may offset part of the initial referral costs.

Undamped ultrafast pulsation of plasmonic fields via coherent exciton-plasmon coupling.

We show that under certain conditions the plasmonic field of a hybrid system consisting of a metallic nanoparticle and a semiconductor quantum dot can be converted into ultrashort stationary pulses with temporal widths as short as 300 ps. This happens as this system interacts with an infrared and visible laser fields, both with time-independent amplitudes. These fields generate quantum coherence via simultaneous interband and intersubband transitions of the quantum dot, forcing the polarization dephasing rate of the quantum dot to become negative during the plasmon pulses. This makes the amplitudes of such pulses time-independent (undamped), indicating total suppression of quantum decoherence of the quantum dot. These results suggest that hybrid quantum dot-metallic nanoparticle systems can act as undamped coherent-plasmonic oscillators.

Dynamics of plasmonic field polarization induced by quantum coherence in quantum dot-metallic nanoshell structures.

When a hybrid system consisting of a semiconductor quantum dot and a metallic nanoparticle interacts with a laser field, the plasmonic field of the metallic nanoparticle can be normalized by the quantum coherence generated in the quantum dot. In this Letter, we study the states of polarization of such a coherent-plasmonic field and demonstrate how these states can reveal unique aspects of the collective molecular properties of the hybrid system formed via coherent exciton-plasmon coupling. We show that transition between the molecular states of this system can lead to ultrafast polarization dynamics, including sudden reversal of the sense of variations of the plasmonic field and formation of circular and elliptical polarization.

Severity of symptoms, physical functioning and satisfaction in patients with lumbar spinal stenosis: a validation study of the Iranian version of the Swiss Spinal Stenosis Score.

AIM: A common cause of low back pain is lumbar spinal stenosis (LSS). The Swiss Spinal Stenosis Score (SSS) is a well-known questionnaire that measures the severity of symptoms, physical functioning and patient's satisfaction in lumbar spinal stenosis. This study aimed to translate and validate the SSS in Iran. METHODS: A prospective clinical validation study was performed. Forward-backward procedure was applied to translate the original questionnaires into Persian. A sample of patients with lumbar spinal stenosis completed the questionnaire twice: at pre- and postoperative (6 months follow-up) assessments. To test reliability the internal consistency was assessed by the Cronbach's alpha coefficient. Validity was evaluated using the known groups comparison. In addition the Oswestry Disability Index was used to perform convergent validity. RESULTS: In all 121 patients were entered into the study. The mean age of patients was 62.3 (SD=10.2) years. The Cronbach's alpha coefficient for the SSS was 0.88. Validity was performed by known groups analysis and showed satisfactory results. The instrument discriminated well between the subgroups of patients who differed in age, severity of lumbar spinal stenosis, and the Self-Paced Walking Test (SPWT). The change in the Oswestry Disability Index strongly correlated with the change in patients' scores on the SSS; lending support to its good convergent validity (r=0.82; P<0.001). CONCLUSION: The Iranian version of Swiss Spinal Stenosis Score performed well and the findings suggest that it is a valid measure of symptoms, physical functioning and satisfaction among patients with lumbar spinal stenosis.