Modelling temperature dynamics in sewer systems - comparing mechanistic and conceptual modelling approaches

The vast majority of the energy consumed for urban water services is used to heat tap water. Heat recovery from wastewater is consequently an area of rapidly growing concern, both in research and by commercial interest, promoting the path towards a circular economy. To facilitate a system-wide evaluation of heat recovery from wastewater, this paper compares two one-dimensional models (mechanistic and conceptual) that can describe wastewater temperature dynamics in sewer pipe systems. The models are applied to successfully predict downstream wastewater temperature for sewer stretches in two Swedish cities (Linköping and Malmö). The root mean squared errors for the mechanistic model (Linköping Dataset1 - 0.33 °C; Linköping Dataset2 - 0.28 °C; Malmö - 0.40 °C) and the conceptual model (Linköping Dataset1 - 0.32 °C; Linköping Dataset2 - 0.20 °C; Malmö - 0.44 °C) indicate that both models have similar predictive capabilities, encouraging the use of conceptual models to reduce data requirements and model calibration efforts. Both models are freely distributed and can be easily integrated with wastewater generation and treatment models to facilitate system-wide wastewater temperature dynamics analysis.

Cerebrovascular Disease and Neurodegeneration in Alzheimer's Disease with and without a Strong Family History: A Pilot Magnetic Resonance Imaging Study in Dominican Republic

The incidence and prevalence of Alzheimer's disease (AD) dementia are higher among Caribbean Hispanics than among non-Hispanic Whites. The causes of this health disparity remain elusive, partially because of the relative limited capacity for biomedical research in the developing countries that comprise Caribbean Latin America. To begin to address this issue, we were awarded a Development Research Award from the US NIH and Fogarty International Center in order to establish the local capacity to integrate magnetic resonance imaging (MRI) into studies of cognitive aging and dementia in Dominican Republic, establish collaborations with Dominican investigators, and conduct a pilot study on the role of cerebrovascular markers in the clinical expression of AD. Ninety older adult participants with and without AD dementia and with and without a strong family history of AD dementia received MRI scans and clinical evaluation. We quantified markers of cerebrovascular disease (white matter hyperintensities [WMH], presence of infarct, and presence of microbleed) and neurodegeneration (entorhinal cortex volume) and compared them across groups. Patients with AD dementia had smaller entorhinal cortex and greater WMH volumes compared with controls, regardless of family history status. This study provides evidence for the capacity to conduct MRI studies of cognitive aging and dementia in Dominican Republic. The results are consistent with the hypothesis that small vessel cerebrovascular disease represents a core feature of AD dementia, as affected participants had elevated WMH volumes irrespective of family history status.

Genetic Variation in Genes Underlying Diverse Dementias May Explain a Small Proportion of Cases in the Alzheimer's Disease Sequencing Project

BACKGROUND/AIMS

The Alzheimer's Disease Sequencing Project (ADSP) aims to identify novel genes influencing Alzheimer's disease (AD). Variants within genes known to cause dementias other than AD have previously been associated with AD risk. We describe evidence of co-segregation and associations between variants in dementia genes and clinically diagnosed AD within the ADSP.

METHODS

We summarize the properties of known pathogenic variants within dementia genes, describe the co-segregation of variants annotated as "pathogenic" in ClinVar and new candidates observed in ADSP families, and test for associations between rare variants in dementia genes in the ADSP case-control study. The participants were clinically evaluated for AD, and they represent European, Caribbean Hispanic, and isolate Dutch populations.

RESULTS/CONCLUSIONS

Pathogenic variants in dementia genes were predominantly rare and conserved coding changes. Pathogenic variants within ARSA, CSF1R, and GRN were observed, and candidate variants in GRN and CHMP2B were nominated in ADSP families. An independent case-control study provided evidence of an association between variants in TREM2, APOE, ARSA, CSF1R, PSEN1, and MAPT and risk of AD. Variants in genes which cause dementing disorders may influence the clinical diagnosis of AD in a small proportion of cases within the ADSP.

Relationship between Social Cognition and traditional cognitive impairment in Progressive Multiple Sclerosis and possible implicated neuroanatomical regions

BACKGROUND

Cognitive impairment is a relevant contributor of the medical and social burden in Progressive MS. Social Cognition, the neurocognitive processes underlying social interaction, has been explored mainly in European and North American cohorts, influencing social aspects of quality of life (QOL) of early MS patients and families. Few studies have studied Social Cognition in Progressive MS and the literature on its neuroanatomical bases or brain atrophy measurements is still scarce.

OBJECTIVES

To explore the relationship between Social Cognition performance and its correlations with traditional cognitive domains, brain atrophy and QOL in primary and secondary Progressive MS patients.

METHODS

Cross-sectional analysis including: mini-Social-Cognition-and-Emotional-Assessment (mini-SEA), neuropsychological battery, disability, depression, fatigue, QOL, and brain volume.

RESULTS

Forty-three MS patients, 23 primary and 20 secondary Progressive, 65% women, mean age and disease duration of 57.2 and 15.7 years, respectively, with high levels of disability (median EDSS 6.0) and a widespread impairment in traditional domains (mostly episodic verbal/visual and working memories) were assessed. The Mini-SEA score was correlated with executive functions (cognitive shifts Rho:0.55; p = 0.001) analyzing the whole group, and with visual episodic memory (Rho:0.58, p = 0.009) in the primary Progressive MS group. Mini-SEA score was also correlated with total normalized grey matter volume (Rho:0.48; p = 0.004). Particularly, atrophy within bilateral cortical regions of orbitofrontal, insula and cerebellum, and right regions of fusiform gyrus and precuneus were significantly associated with higher Social Cognition impairment. In this cohort, QOL was not correlated with Social Cognition, but with EDSS, fatigue and depression.

CONCLUSIONS

In Progressive MS, Social Cognition is directly correlated with traditional cognitive domains such as executive function and episodic memory. It is also associated with global grey matter atrophy and regional atrophy within associative visual and executive cortical areas, but no correlations with QOL were found in this cohort. These findings may contribute to the understanding of the pathological bases behind Social Cognition in Progressive MS.

Inhomogeneous spatial distribution of the magnetic transition in an iron-rhodium thin film

Monitoring a magnetic state using thermal or electrical activation is mandatory for the development of new magnetic devices, for instance in heat or electrically assisted magnetic recording or room-temperature memory resistor. Compounds such as FeRh, which undergoes a magnetic transition from an antiferromagnetic state to a ferromagnetic state around 100 °C, are thus highly desirable. However, the mechanisms involved in the transition are still under debate. Here we use in situ heating and cooling electron holography to quantitatively map at the nanometre scale the magnetization of a cross-sectional FeRh thin film through the antiferromagnetic–ferromagnetic transition. Our results provide a direct observation of an inhomogeneous spatial distribution of the transition temperature along the growth direction. Most interestingly, a regular spacing of the ferromagnetic domains nucleated upon monitoring of the transition is also observed. Beyond these findings on the fundamental transition mechanisms, our work also brings insights for in operando analysis of magnetic devices.

Films of iron-rhodium alloy undergo a magnetic transition at 100°C, and so are attractive for applications, but a detailed understanding of the transition mechanism has not been achieved. Here, the authors use electron holography to quantitatively map the transition's progress through the film depth.

Magnetic Configurations in Co/Cu Multilayered Nanowires: Evidence of Structural and Magnetic Interplay

Off-axis electron holography experiments have been combined with micromagnetic simulations to study the remnant magnetic states of electrodeposited Co/Cu multilayered nanocylinders. Structural and chemical data obtained by transmission electron microscopy have been introduced in the simulations. Three different magnetic configurations such as an antiparallel coupling of the Co layers, coupled vortices, and a monodomain-like state have been quantitatively mapped and simulated. While most of the wires present the same remnant state whatever the direction of the saturation field, we show that some layers can present a change from an antiparallel coupling to vortices. Such a configuration can be of particular interest to design nano-oscillators with two different working frequencies.

Comparison between retrograde intrarenal surgery and extracorporeal shock wave lithotripsy in the treatment of lower pole kidney stones up to 15 mm. Prospective, randomized study

INTRODUCTION

Extracorporeal Shock Wave Lithotripsy (ESWL) is currently the recommended treatment for intra-renal calculi smaller than 2 cm. However the low Stone Free Rate (SFR) in lower pole calculi gives rise to new techniques, such us retrograde intrarenal surgery (RIRS), for improve the surgery outcomes.

OBJECTIVE

To compare the efficacy of a treatment with ESWL with RIRS, in terms of SFR after surgery, in patients with kidney stones up to 15 mm in the lower pole.

MATERIAL AND METHODS

A prospective study was carried out in order to assess the results of ESWL and RIRS in patients with lower pole stones less than 15 mm. Among a total of 55 patients, 31 were underwent to ESWL (Group 1) and the remaining 24 to RIRS (Group 2). Clinical data recorded, including general characteristics of each patient, were: calculi size, side, operative time, complications according to Clavien scale, SFR and the presence of residual fragments at 2 months post-treatment assessed by a CT scan. STATA 11 was used to perform the statistical analysis.

RESULTS

There were no differences for general descriptors among groups with the exception of a significantly longer operative time for RIRS. The rates of SFR and residual fragments lesser than 3 mm. were lower in the RIRS group than in ESWL ones. RIRS also showed a lower rate of clinically significant fragments (0% vs 42.3%. P < .05). In the subgroup of patients with stones between 10/15 mm RIRS showed higher SFR (75% vs. 41.2%) and a lower rate of stones>3 mm (0% vs. 58.8%), being statistically significant (P < .05). Clavien III or higher complications were not reported in any of the groups.

CONCLUSIONS

In the treatment of lower pole stone RIRS has the same results than ESWL in terms of SFR. Regarding absence of a clinically significant residual fragment, RIRS was superior to ESWL. A bigger sample size is required in order to confirm this results.

Intraoperative cystography pre- and post-endoscopic treatment for vesicoureteral reflux: guaranteed success?

OBJECTIVE

This study was designed to investigate whether post-endoscopic treatment (ET) intraoperative cystography is predictive of treatment outcome.

PATIENTS AND METHODS

Patients diagnosed with vesicoureteral reflux (VUR) and treated endoscopically with polyacrylate/polyalcohol copolymer or dextranomer hyaluronic acid were studied prospectively between August 2009 and April 2011. Slow infusion pre-ET cystography was performed under anesthesia. Post-ET cystography was performed only if the intraoperative pre-ET results demonstrated VUR.

RESULTS

Over a period of 20 months, 23 patients were studied (18 girls, five boys), with an average age of 41.9 months (range 13 months-11 years). Thirty-two renal units with reflux were treated: nine bilateral cases, seven right, and seven left. The distribution of reflux grades was as follows: two grade I, 10 grade II, 11 grade III, nine grade IV. All injected ureters demonstrated grade 0 hydrodistention after the procedure. Twelve of 23 of the pre-ET cystography results were negative for VUR, indicating that the sensitivity of this test is 47% compared with the preoperative voiding cystourethrography (VCUG) or nuclear cystogram. There were no procedure complications.

CONCLUSION

Of all patients (n = 23), nearly 60% did not demonstrate pre-ET VUR on intraoperative cystography. If a postoperative VCUG had been performed on all patients, more than half would have received unnecessary radiation. Therefore, this study demonstrates that post-ET cystography does not predict the success of ET of VUR intraoperative. Pre-ET cystography under general anesthesia before ureteral injection, has very low sensitivity, creating false-negatives that may complicate the interpretation of post-ET cystography. We suggest that intraoperative cystography before and after ET fails to show clinical utility and should not be used to predict the outcome of endoscopic VUR treatment.

Tumour cell lysate-loaded dendritic cell vaccine induces biochemical and memory immune response in castration-resistant prostate cancer patients

Background:

Recently, we produced a tumour antigen-presenting cells (TAPCells) vaccine using a melanoma cell lysate, called TRIMEL, as an antigen source and an activation factor. Tumour antigen-presenting cells induced immunological responses and increased melanoma patient survival. Herein, we investigated the effect of TAPCells loaded with prostate cancer cell lysates (PCCL) as an antigen source, and TRIMEL as a dendritic cell (DC) activation factor; which were co-injected with the Concholepas concholepas haemocyanin (CCH) as an adjuvant on castration-resistant prostate cancer (CRPC) patients.

Methods:

The lysate mix capacity, for inducing T-cell activation, was analysed by flow cytometry and Elispot. Delayed-type hypersensitivity (DTH) reaction against PCCL, frequency of CD8⁺ memory T cells (Tm) in blood and prostate-specific antigen (PSA) levels in serum were measured in treated patients.

Results:

The lysate mix induced functional mature DCs that were capable of activating PCCL-specific T cells. No relevant adverse reactions were observed. Six out of 14 patients showed a significant decrease in levels of PSA. DTH⁺ patients showed a prolonged PSA doubling-time after treatment. Expansion of functional central and effector CD8⁺ Tm were detected.

Conclusion:

Treatment of CRPC patients with lysate-loaded TAPCells and CCH as an adjuvant is safe: generating biochemical and memory immune responses. However, the limited number of cases requires confirmation in a phase II clinical trial.

Antibiotic resistance patterns of Escherichia coli isolates from different aquatic environmental sources in León, Nicaragua

Antibiotic-resistant bacteria have emerged due to the selective pressure of antimicrobial use in humans and animals. Water plays an important role in dissemination of these organisms among humans, animals and the environment. We studied the antibiotic resistance patterns among 493 Escherichia coli isolates from different aquatic environmental sources collected from October 2008 to May 2009 in León, Nicaragua. High levels of antibiotic resistance were found in E. coli isolates in hospital sewage water and in eight of 87 well-water samples. Among the resistant isolates from the hospital sewage, ampicillin, chloramphenicol, ciprofloxacin, nalidixic acid, trimethoprim-sulphamethoxazole was the most common multi-resistance profile. Among the resistant isolates from the wells, 19% were resistant to ampicillin, ceftazidime, ceftriaxone, cefotaxime, chloramphenicol, ciprofloxacin, gentamicin, nalidixic acid and trimethoprim-sulphamethoxazole. E. coli producing ESBL and harbouring bla(CTX-M) genes were detected in one of the hospital sewage samples and in 26% of the resistant isolates from the well-water samples. The bla(CTX-M-9) group was more prevalent in E. coli isolates from the hospital sewage samples and the bla(CTX-M-1) group was more prevalent in the well-water samples.

Note: fast, small, and low vibration mechanical laser shutters

We present three novel mechanical laser shutter designs based, respectively, on a stepper motor, a relay, and a piezoelectric actuator. Each shutter type is ideally suited to a specific shuttering application. The stepper motor is well suited for applications requiring low vibrations, the relay is compact and capable of rapid bursts, and the piezoelectric is 2 orders of magnitude faster than other available mechanical shutters.

Familial aggregation of dementia with Lewy bodies

BACKGROUND

Familial aggregation of dementia with Lewy bodies (DLB) remains unclear.

OBJECTIVES

To determine the degree of family aggregation of DLB by comparing DLB risk between siblings of probands with clinically diagnosed DLB and siblings of probands with clinically diagnosed Alzheimer disease in a cohort of Caribbean Hispanic families and to explore the degree of aggregation of specific clinical manifestations (ie, cognitive fluctuations, visual hallucinations, and parkinsonism) in DLB.

DESIGN

Familial cohort study.

SETTING

Academic research.

PATIENTS

We separately compared risks of possible DLB, probable DLB, and clinical core features of DLB (cognitive fluctuations, visual hallucinations, and parkinsonism) between siblings of probands with clinically diagnosed DLB (n = 344) and siblings of probands with clinically diagnosed Alzheimer disease (n = 280) in 214 Caribbean Hispanic families with extended neurologic and neuropsychological assessment.

MAIN OUTCOME MEASURES

We applied general estimating equations to adjust for clustering within families. In these models, age and proband disease status were independent variables, and disease status of siblings was the measure of disease risk and the dependent variable.

RESULTS

Compared with siblings of probands having clinically diagnosed Alzheimer disease, siblings of probands having clinically diagnosed DLB had higher risks of probable DLB (odds ratio [OR], 2.29; 95% confidence interval [CI], 1.04-5.04) and visual hallucinations (2.32; 1.16-4.64). They also had increased risks of possible DLB (OR, 1.51; 95% CI, 0.97-2.34) and cognitive fluctuations (1.55; 0.95-2.53).

CONCLUSIONS

Dementia with Lewy bodies and core features of DLB aggregate in families. Compared with siblings of probands having clinically diagnosed AD, siblings of probands having clinically diagnosed DLB are at increased risks of DLB and visual hallucinations. These findings are an important step in elucidating the genetic risk factors underlying DLB and in delineating DLB from other neurodegenerative diseases, such as Alzheimer disease.

Standardized treatment and follow-up protocol of hepatocellular carcinoma with transcatheter arterial chemoembolization: Survival, clinical, and tumor control outcome over 12 years at a U.S. center

e15522

Background: To report the outcome of the care of patients with hepatocellular carcinoma (HCC) treated with standardized transcatheter arterial chemomembolization (TACE), with a focus on tumor response according to Response Evaluation Criteria in Solid Tumors (RECIST), progression of underlying cirrhosis [Child-Pugh (CP) score], time to progression (TTP) and survival from 1996 to 2008. Methods: TACE was performed on 365 patients in 1,035 sessions. According to a standardized protocol, all patients received imaging (MRI and/or CT) at baseline and at 4–6 weeks after each session and were clinically, biochemically and radiologically evaluated before each session. Liver disease status was evaluated before and at the end of the treatment period with the CP class system and tumor size measurements according to the RECIST. The Barcelona Clinic Liver Cancer (BCLC) classification was employed to stage patients. Three chemotherapeutic agents and lipiodol, followed by non-occlusive embolization were utilized during TACE. Complete vessel occlusion was avoided at all times. Overall survival and TTP were calculated according to the Kaplan-Meier method. The log-rank test was used to calculate differences between groups in the subgroup analysis. Results: All patients (78% male, mean age: 63.5 years) received an average of 3 TACE sessions (range: 1–10 and average interval between sessions: 75 days). Sixty six percent of patients had 3 or more tumors, with a mean tumor size at presentation of 6.9 cm. Partial response was achieved in 32 % of patients, while 65% remained stable over the course of 3 TACEs. CP class remained unchanged for 75% of patients over the above course of treatment. Median survival for the entire cohort was 20 months and TTP was 14 months. Interestingly, advanced BCLC patients achieved similar tumor response (PR:33%), TTP of 13.4 months and median survival of 13.7 months. Conclusions: Patients with HCC treated with the aforementioned standardized TACE and follow-up protocol showed durable survival, stable liver disease and effective tumor control.

[Table: see text]

Dimensional crossover in anisotropic Kondo lattices

Dimensional crossover in the Kondo necklace model is analyzed using the bond-operator method at zero and finite temperatures. Explicit relations describing quasi-two-dimensional properties are obtained by asymptotically solving the resulting equations. The crossover from two dimensions (2d) to three dimensions (3d) is investigated, turning on the electronic hopping ([Formula: see text]) of conduction electrons between different planes. In order to give continuity to our analysis, both cases of crossover, quasi-three-dimensional (q3d) and quasi-one-dimensional (q1d), are also investigated. The phase diagram as a function of temperature T, [Formula: see text] and [Formula: see text], where [Formula: see text] is the hopping within the planes, is calculated. Unusual reentrant behavior in the temperature-dependent antiferromagnetic critical line is found close to two dimensions. Near the isotropic three-dimensional quantum critical point the critical line is described by a standard power law with a square root dependence on the distance to the quantum critical point.

Role of cytokines (interleukin-1beta, 6, 8, tumour necrosis factor-alpha, and soluble receptor of interleukin-2) and C-reactive protein in the diagnosis of neonatal sepsis

AIM

To investigate whether the serum levels of interleukin-1beta, 6, 8, tumour necrosis factor-alpha and the soluble receptor of IL-2 are useful in the diagnosis of neonatal sepsis, and whether their diagnostic power is increased when in combination with classical markers such as C-reactive protein and white blood cell count.

METHODS

Blood samples were collected at admission from 40 neonates with suspected infection. Patients were included in different groups according to the bacteriological and laboratory results: Group I consisted of 20 newborns with positive blood cultures and other biological tests suggestive of infection. Group II included 20 neonates with negative blood cultures and biological tests not suggestive of infection. The control group included 20 healthy neonates with no clinical or biological data of infection.

RESULTS

Mean values of C-reactive protein were significantly higher in Group I. No differences were found between the groups for white blood cell count, with the exception of the presence of leucocytosis in Group II. Levels of interleukin-1beta, 6, 8, tumour necrosis factor-alpha, soluble receptor of interleukin-2, and C-reactive protein were significantly higher in infected neonates than in the control groups. Detection sensitivity and specificity were 80 and 92% for C-reactive protein, 60 and 87% for interleukin-1beta, 61 and 80% for interleukin-6, 62 and 96% for interleukin-8, 54 and 92% for tumour necrosis factor-alpha and 63 and 94% for soluble receptor of interleukin-2. The discriminant analysis showed that the best combination for sepsis diagnosis was C-reactive protein + interleukin-8 + soluble receptor of interleukin-2, with a sensitivity of 85% and a specificity of 97.1%.

CONCLUSION

Our study suggests that no individual test can on its own identify infected neonates, and that although the combination of C-reactive protein, interleukin-8 and the soluble receptor of interleukin-2 exhibits a high specificity, its sensitivity is limited.

Early sepsis, obstructive jaundice and right-sided diaphragmatic hernia in the newborn

A male newborn was admitted to our Unit because of early sepsis and shock. He required antimicrobial therapy and mechanical ventilation and initially did well, although he exhibited jaundice and cholestasis. During the second week he deteriorated, with radiological opacification of the right hemithorax and pleural effusion, and did poorly in spite of antibiotical therapy and drainage of the effusion. In the third week, the X-ray suggested some bowel loops in the right hemithorax. A right-sided diaphragmatic hernia was confirmed by a CT-scan, and surgery was performed with good outcome. The association of delayed-onset right-sided CDH following early sepsis and obstructive jaundice has not been published before, and illustrates a scarcely known form of presentation of this condition.

Antipsychotic drugs and reproductive hormones: relationship to body weight regulation

Excessive body weight gain is an undesirable side effect of prolonged administration of antipsychotic drugs (AP), which affects health and interferes with treatment compliance. It has been suggested that hyperprolactinemia-induced endocrine and metabolic abnormalities, particularly in the gonadal steroids, might be involved in the development of this type of weight gain. To test this hypothesis, reproductive hormones, cortisol, dehydro-epiandrosterone-sulfate (DHEA-S), thyroid hormones, and body weight gain were assessed in 18 patients (9 men, 9 women) with mental disorders receiving AP who had been medication-free for at least 3 months before the study, and in 27 placebo-treated subjects (10 men, 17 women). In women, hormones were evaluated during several phases of the menstrual cycle. A significant weight gain was observed in men but not in women. Under AP administration, women displayed significantly lower serum levels of estradiol and progesterone, whereas in men the levels of free testosterone and DHEA-S were significantly lower than in controls. Hyperprolactinemia was observed in both sexes. The levels of follicle-stimulating hormone in women and luteinizing hormone in men were significantly elevated by treatment, thus suggesting that the functioning of the hypothalamus-pituitary gonads was preserved. In men, such an endocrine profile resembles that observed in subjects with primary obesity. Women under AP administration were found to be relatively hyperandrogenic because of decreased serum estradiol levels, whereas women with primary obesity are known to display actual increased levels of androgens. These endocrine abnormalities may contribute to the excessive weight gain observed after AP treatment, and these could be the target of novel pharmacological treatments.

Perianal disease of tuberculous origin: report of a case and review of the literature

PURPOSE

A case of anal tuberculosis in an otherwise asymptomatic patient with bleeding anal ulcers is presented. The clinical features of this entity and the problems in differential diagnosis between anal infectious vs. inflammatory diseases are discussed.

METHODS

The management and outcome of the case of an adult patient who presented with perianal ulcers is described.

RESULTS

On a three-drug antituberculous regimen, symptoms abated, radiographic infiltrates improved, and perianal ulcers healed.

CONCLUSION

Anal tuberculosis is an extremely rare disease. A tuberculous origin must be considered when the cause of perianal ulcers is unclear to avoid undesirable delays in the diagnosis and treatment of this disease.

An in-house coordinator program to increase organ donation in public trauma hospitals

A 4-year retrospective study was conducted regarding the donor potential, consent rates, and organ recovery at a large 500-bed public trauma hospital. An independent organ procurement organization hired two in-house coordinators, one white and one black, to work exclusively in the hospital. The duties of the in-house coordinators included the following: working with nurses, physicians, and residents to identify donors; closely managing and coordinating the consent process; and assisting organ procurement coordinators in donor management. Following the program's implementation and the use of race-specific requesters, a 64% increase in consent rate resulted along with an overall increase of 94% in the number of organ donors. The consent rate of blacks increase 115%, whereas the number of black organ donors increased 154%. The Hispanic consent rate increased 48% with a corresponding increase of 83% in the number of Hispanic organ donors. In addition, the white consent rate increased from 55% (the 3-year average from 1993 to 1995) to 75% in 1996, resulting in a 36% increase following the implementation of the program. The investment of dedicated race-sensitive personnel in large urban county trauma facilities can result in a significant increase in donor conversion rates.

Two-Day Hydrophobic Grid Membrane Filter Method for Yeast and Mold Enumeration in Foods Using YM-11 Agar: Collaborative Study

Twenty laboratories participated in a collaborative study to validate a 2-day hydrophobic grid membrane filter method using YM-11 agar for enumeration of yeast and mold in foods. Six naturally contaminated food products were included in the study: garlic powder, raw ground beef, walnuts, flour/meal, orange juice, and yogurt. The test method produced significantly higher results than the 5-day pour plate reference method for orange juice and significantly lower, though numerically similar, results for walnuts and yogurt. Differences between the test and reference methods were not significant for garlic powder, raw ground beef, or flour/meal. Repeatability and reproducibility were similar for both the test and reference methods in all cases. The hydrophobic grid membrane filter method for enumeration of yeast and mold in foods has been adopted by AOAC INTERNATIONAL.

Involvement of N- and non-N-type calcium channels in synaptic transmission at corticostriatal synapses

Calcium channels participate in the events linking axon terminal depolarization to neurotransmitter secretion. We wished to evaluate the role of N-type and non-N-type calcium channels in glutamatergic transmission at corticostriatal synapses, since this is a well defined excitatory synapse. In addition, these synapses are subject to a variety of forms of presynaptic modulation, some of which may involve alterations in calcium channel function. Application of the selective N-type channel blocker omega-conotoxin GVIA produced an irreversible depression of excitatory synaptic transmission in rat neostriatal slices shown by a decrease of approximately 50% in the amplitude of the synaptically driven population spike during field potential recording and a similar decrease in the amplitude of excitatory postsynaptic potentials during whole-cell recording. The component of transmission which was resistant to omega-conotoxin GVIA was blocked by omega-conotoxin MVIIC. omega-Agatoxin IVA had little effect on transmission. Activation of a presynaptic metabotropic glutamate receptor depressed transmission to a similar extent before and after omega-conotoxin GVIA treatment. Likewise, protein kinase C-activating phorbol esters potentiated transmission to the same extent before and after omega-conotoxin GVIA treatment. N-type calcium channels appear to be crucial for a component of excitation-secretion coupling at corticostriatal synapses. A component of transmission involves non-N-, non-L-type high-voltage-activated calcium channels. The effects of presynaptic metabotropic receptors and protein kinase C activation cannot be accounted for solely by alterations in the N-type channel function.