Withdrawal Pattern Research Articles

Brain Responses Difference between Sexes for Strong Desire to Void: A Functional Magnetic Resonance Imaging Study in Adults Based on Graph Theory.

Background: The alternations of brain responses to a strong desire to void were unclear, and the gender differences under the strong desire to void remain controversial. The present study aims to identify the functional brain network's topologic property changes evoked by a strong desire to void in healthy male and female adults with synchronous urodynamics using a graph theory analysis. Methods: The bladders of eleven healthy males and eleven females were filled via a catheter using a specific infusion and withdrawal pattern. A resting-state functional magnetic resonance imaging (fMRI) was performed on the enrolled subjects, scanning under both the empty bladder and strong desire to void states. An automated anatomical labeling (AAL) atlas was used to identify the ninety cortical and subcortical regions. Pearson's correlation calculations were performed to establish a brain connection matrix. A paired t-test (p < 0.05) and Bonferroni correction were applied to identify the significant statistical differences in topological properties between the two states, including small-world network property parameters [gamma (γ) and lambda (λ)], characteristic path length (Lp), clustering coefficient (Cp), global efficiency (Eglob), local efficiency (Eloc), and regional nodal efficiency (Enodal). Results: The final data suggested that females and males had different brain response patterns to a strong desire to void, compared with an empty bladder state. Conclusions: More brain regions involving emotion, cognition, and social work were active in females, and males might obtain a better urinary continence via a compensatory mechanism.

Forecasting ATM Cash Demand Before and During the COVID-19 Pandemic Using an Extensive Evaluation of Statistical and Machine Learning Models.

The overarching goal of this paper is to accurately forecast ATM cash demand for periods both before and during the COVID-19 pandemic. To achieve this, first, ATMs are categorized based on accessibility and surrounding environmental factors that significantly affect the cash withdrawal pattern. Then, several statistical and machine learning models under different algorithms and strategies are employed. In aiming to provide the feature matrix for machine learning models, some new influential variables are added to the literature. Finally, a modified fitness measure is proposed for the first time to correctly choose the most promising model by considering both the prediction errors and accuracy of direction’s change simultaneously. The results obtained by a comprehensive analysis—a statistical analysis together with grid search and k-fold cross-validation techniques—reveal that (i) category-wise prediction enhances forecasting quality; (ii) before COVID-19 and in times when there are only minor disturbances in withdrawal patterns, forecasting quality is higher, and in general, the machine learning models can more appropriately forecast ATM’s cash demand; (iii) despite studies in the literature, sophisticated models will not always outperform simpler models. It is found that during COVID-19 and in times when there is a sudden shock in demand and massive volatility in withdrawal patterns, the statistical models of the autoregressive integrated moving average (ARIMA) and seasonal ARIMA (SARIMA) can mainly provide better forecasting likely due to high performance of such models for short-term prediction, while minimizing overfitting.Supplementary InformationThe online version contains supplementary material available at 10.1007/s42979-021-01000-0.

Decreased complications but a distinctive fixation loosening mechanism of fully threaded headless cannulated screw fixation for femoral neck fractures in young adults

BackgroundDespite being a commonly encountered injury in orthopedic practice, controversy surrounds the methods of optimal internal fixation for femoral neck fractures (FNF) in young patients. The objective of the present study is to compare complication rates and failure mechanisms for surgical fixation of FNF using fully threaded headless cannulated screws (FTHCS) versus partial threaded cannulated screws (PTS) in young adults.MethodsA total of 75 patients (18–65 years old) with FNF were prospectively treated with close reduction and internal fixation using three parallel FTHCS and compared to a historical control case-matched group (75 patients) with FNF treated by PTS fixation. After 2 years follow-up, rates of fixation failure (including varus collapse, fracture displacement, and femoral neck shortening), nonunion, and avascular necrosis of the femoral head (ANFH) were compared between the two cohorts. The demographic, follow-up information, and radiological images were assessed by independent blinded investigators.ResultsPatient demographics and fracture patterns were similar in the two patient groups. The overall fixation failure rates were 8% (6/75) in the FTHCS cohort, which was significantly lower than the 25.3% (19/75) seen in the PTS group. Rates of nonunion and ANFH were significantly lower in the FTHCS group when compared to the PTS control group. When stratified by injury severity (high-energy vs. low-energy fractures), the rate of fixation failure was significant lower with the use of FTHCS when compared with PTS for high-energy fractures while there was no difference in the rates of nonunion or ANFH for high or low-energy fracture patterns. Unique to the FTHCS cohort was an atypical screw migration pattern with varus collapse (6/75, 8%).ConclusionsThe results show that FTHCS fixation could significantly reduce the complication rate of young patients with FNF, especially in high-energy fracture patterns (Garden III–IV, Pauwels III, or vertical of the neck axis (VN) angle ≥ 15°). There was also confirmation that the modes of fixation loosening in the FTCHS group, including screw “medial migration” and superior cutout, were different from the screw withdrawal pattern seen in the PTS cohort.Trial registrationThe study was retrospectively registered at www.Chictr.org.cn (ChiCTR-IPR-1900025851) on September 11, 2019.

Stochastic optimization of comfort-centered model of electrical water heater using mixed integer linear programming

This paper introduces a new strategy for controlling electric water heaters (EWH) using mixed-integer linear programming (MILP). It has two major contributions: 1) To balance between cost savings and the discomfort (cold water) that Demand Response (DR) could bring, the discomfort is modeled as undelivered energy in the objective of the problem rather than a thermal constraint. This improves both sides of the cost-saving Vs. User-comfort trade-ff. 2) in EWH control, many previous works only rely on electricity prices for scheduling. However, this work is among the very few works that also consider consumption for scheduling. Further, by treating the hot water withdrawal pattern as a random variable, the algorithm finds the best setpoints for EWH via stochastic optimization over a range of possible hot water withdrawal patterns, rather than requiring perfect foresight of withdrawal. The result of these changes is an algorithm that can let the temperature fall below minimum when probability of energy usage is low without affecting user comfort while other methods always keep the temperature above minimum. The effectiveness of this approach on improving both sides of the cost Vs. discomfort trade-off and the effectiveness of stochastic approach is confirmed by comparison with two other methods.

Conditioned pain modulation affects the withdrawal reflex pattern to nociceptive stimulation in humans

Human studies have repeatedly shown that conditioning pain modulation (CPM) exerts an overall descending inhibitory effect over spinal nociceptive activity. Previous studies have reported a reduction of the nociceptive withdrawal reflex (NWR) under CPM. Still, how descending control influences the muscle activation patterns involved in this protective behavior remains unknown. This study aimed to characterize the effects of CPM on the withdrawal pattern assessed by a muscle synergy analysis of several muscles involved in the lower limb NWR. To trigger descending inhibition, CPM paradigm was applied using the cold-pressor test (CPT) as conditioning stimulus. Sixteen healthy volunteers participated. The NWR was evoked by electrical stimulation on the arch of the foot before, during and after the CPT. Electromyographic (EMG) activity of two proximal (rectus femoris and biceps femoris) and two distal (tibialis anterior and soleus) muscles was recorded. A muscle synergy analysis was performed on the decomposition of the EMG signals, based on a non-negative matrix factorization algorithm. Results showed that two synergies (Module I and II) were sufficient to describe the NWR pattern. Under CPM, Module I activation amplitude was significantly reduced in a narrow time-window interval (118–156 ms) mainly affecting distal muscles, whereas Module II activation amplitude was significantly reduced in a wider time-window interval (150–250 ms), predominantly affecting proximal muscles. These findings suggest that proximal muscles are largely under supraspinal control. The descending inhibitory drive exerted onto the spinal cord may adjust the withdrawal pattern by differential recruitment of the muscles involved in the protective behavior.

Holistic Approach to Sustainable Groundwater Management in Semi-arid Regions

Owing to rational deep understanding of intrinsic nature of groundwater as common pool and decayable resources, together with, lack of withdrawal control by local states, groundwater depletion has been incredibly under consistent withdrawal. Under these circumstances, attempts have been made by users to maximize withdrawal without considering any limitation on account of lack of reliable withdrawal pattern. In this research, sustainable management of groundwater in south western part of Tehran plain has been evaluated by coupling simulation and optimization models of cooperative and non-cooperative approaches. The MODFLOW model and the Artificial Neural Network model are used for simulation of different scenarios after calibration and validation. Then, a non-linear optimization model is used for optimal allocation of groundwater to different water users. Results indicate that users may gain more benefit in early years of withdrawal in non-cooperative approach. However, this may have an adverse effect which implies a decreasing trend in the benefit in such a way that it reaches null in long term period, as this is reflected by dramatic drawdown of groundwater level and its depletion. In cooperative approach, rate of withdrawal from aquifer is determined by considering renewable water volume, together with, groundwater table drawdown constraint. In this approach, water users may gain less benefit than non-cooperative in early years of withdrawal, however, that will offset in 50 years period by means of more benefit.

Analgesic Appraisal of Bidens pilosa (Asteraceae) Leaf Extracts Used in Management of Oral Lesion Pain in HIV/AIDS Patients in Rodents

Oral lesions, diarrhoea, Pneumocystis carinii pneumonia, tuberculosis and urinary tract infections are some of the opportunistic infections (OIs) which arise when the CD4 cells of the HIV/AIDS patient fall below 200 cells/mm3. HIV/AIDS infection complications include tissue damage from oral lesions accompanied with pains. Pain is a disagreeable sensory and sensitive experience associated with actual or potential tissue damage. This condition requires immediate treatment with analgesics and antibiotics. However, the inability of rural dwellers to afford readily available drugs is a consequence for using herbs like Bidens pilosa whose local usefulness in the management of oral lesions of HIV/AIDS has not been proven scientifically. Therefore, the objective of this study was to provide the scientific basis in rats for the traditional healers’ use of Bidens pilosa leaves’ extracts in managing pain associated with oral lesions of HIV/AIDS patients in South Western Uganda. Assessment of the analgesic effects of Bidens pilosa was conducted using acetic acid in mice, formalin-induced pain and tail flick methods in rats. Both aqueous and ethanolic extracts of the leaves of Bidens pilosa produced statistically significant dose dependent inhibition of acetic acid induced pain, non dose dependent pain reduction in formalin induced pain, (p < 0.05; student t-test) and non dose dependent tail withdrawal pattern (p < 0.05, Multivariate ANOVA test). Hence, we conclude that extracts of Bidens pilosa have an analgesic basis for their local use in treatment of oral lesions associated pain in HIV/AIDS patients in South-Western Uganda.

Contributors’ Withdrawal from Online Collaborative Communities: The Case of OpenStreetMap

Online collaborative communities are now ubiquitous. Identifying the nature of the events that drive contributors to withdraw from a project is of prime importance to ensure the sustainability of those communities. Previous studies used ad hoc criteria to identify withdrawn contributors, preventing comparisons between results and introducing interpretation biases. This paper compares different methods to identify withdrawn contributors, proposing a probabilistic approach. Withdrawals from the OpenStreetMap (OSM) community are investigated using time series and survival analyses. Survival analysis revealed that participants’ withdrawal pattern compares with the life cycles studied in reliability engineering. For OSM contributors, this life cycle would translate into three phases: “evaluation,” “engagement” and “detachment.” Time series analysis, when compared with the different events that may have affected the motivation of OSM participants over time, showed that an internal conflict about a license change was related to largest bursts of withdrawals in the history of the OSM project. This paper not only illustrates a formal approach to assess withdrawals from online communities, but also sheds new light on contributors’ behavior, their life cycle, and events that may affect the length of their participation in such project.

Model of withdrawal pattern in terms of residential area development

Model of withdrawal pattern in terms of residential area development

Effects of conditioned pain modulation on the withdrawal pattern to nociceptive stimulation in humans – Preliminary results

Abstract Aims Conditioned pain modulation (CPM) is a paradigm employed to assess descending control of spinal nociception. Previous studies have shown that CPM affects the nociceptive withdrawal reflex (NWR) threshold (RTh), typically assessed in one muscle. However, the NWR activates not one but a group of synergistic muscles, which are recruited by common neural commands to achieve the limb withdrawal. In this regard, synergy analysis can provide the minimum coordinated recruitment of groups of muscles with specific activation balances that describe a movement. The aim was to assess how CPM modulate the global withdrawal strategy of the lower limb expressed by synergy analysis. Methods Sixteen healthy subjects received electrical stimulation in the arch of the foot at 2 × RTh intensity assessed at the biceps femoris muscle, to elicit the NWR at three time points: before, during and after immersion of the hand in cold water at 2.6 ± 0.4° (cold pressor test, CPT) to trigger CPM. Electromyographic signals (EMG) were recorded from 2 distal muscles (tibialis anterior, soleus) and 2 proximal muscles (biceps femoris, rectus femoris). Muscle synergies were identified by a non-negative matrix factorization algorithm for the EMG envelope in the 60–180 ms post-stimulus interval. Data were analyzed by a point-by-point Wilcoxon test using a permutation strategy. Results The overall withdrawal pattern was explained by two main synergies (Syn1 and Syn2). Syn1 mainly contributes to EMG of distal muscles, whereas Syn2 contributes to EMG of proximal muscles. During CPT, the magnitude of Syn2 was reduced in the 160–180ms post-stimulus interval (p &lt; 0.05), whereas no changes were found for Syn1. Conclusions At least two synergies are required to explain the NWR. Furthermore, results suggest that CPM might differentially affect proximal and distal muscles. Further analysis is needed to provide additional information about the behavior of the individual muscles.

Spatial rainfall patterns associated with Indian northeast monsoon derived from high resolution rainfall estimates of Chennai DWR

The Indian northeast monsoon (NEM) season benefits the southeastern parts of peninsular India during the period October-November-December (OND). In this study, which is a first of this type for the Indian region, certain new and salient features of the NEM rainfall (RF) have been derived utilising the very high resolution (333 m × 333 m) radar estimated rainfall (RERF) data generated by the Doppler Weather Radar (DWR) at Chennai for the 12 year period (2002-13), over a circular area of 100 km radius spreading over both land and ocean. More than 2.8 lakhs of grid point data per day have been processed. Rain gauge measured rainfall (RGRF) data of 34 inland stations has also been used. Monthwise spatial distributions of RERF for October, November and December and for the entire season OND have been generated. It is shown through rigorous analysis that RERF is heavier closer to the coast and for a given longitude over land, southern latitudes receive 10-15% more RF than the northern latitudes. Decrease of RF eastwards into Bay of Bengal (BoB) is gradual whereas westwards over inland it is sharp and almost linear. By and large, the climatological features of NEM derived from historical analysis of RGRF data are well-captured by the analysis based on RERF data. A few new features of monthly and seasonal RF have also been identified. For the 34 stations, 12 year data set for OND, the mean RERF and RGRF values are 629.8 mm and 627.4 mm respectively yielding a difference of just 2.4 mm but with a substantial mean absolute deviation of 69.2 mm. RERF during pre-NEM days of Oct contributed to 10% of the seasonal OND total. RERF in the area of study, during days of cyclonic disturbances (CD days) is nearly twice over outer oceanic areas of BoB than over land. It has been shown that during the onset to withdrawal period of NEM, RERF is heavier over areas close to the coast (75 cm) than oceanic areas (68 cm) within the 100 km radius of the DWR. High RF zones approximately extending 25-30 km westwards into land and around 30-40 km eastwards over the ocean have been delineated. Spatial distributions of RERF during the various phases of NEM, viz., dry, weak, normal, active and vigorous as identified from the RGRF data have been generated, critically analysed and results drawn. In the case of vigorous, active and vigorous (AV) NEM days excluding CD days, a relatively high daily RERF patch of 5-6 cm located approximately 5-10 km west of the coast inland and in the SW sector of Chennai DWR has been identified. During post-NEM withdrawal days of December, oceanic areas of eastern sector are shown to receive highest RF compared to land areas, a feature consistent with the withdrawal pattern of NEM. The instrumental limitations and artifacts of radars contributing to errors in RERF have been discussed.

The Impact of the 2008 Financial Crisis on Withdrawals of Retirement Wealth

During the financial crisis of 2007–2009, the market value of retirement assets held in stock fell by 32%. The objective of this study is to show how a severe financial crisis affects the withdrawal patterns of retirees. Specifically, the authors examine how withdrawal patterns change when an unexpected major investment shock at various years into retirement is induced artificially. The results show that equally weighted portfolio of stocks and bonds performs better than a portfolio of 100% stock, or a portfolio of 100% bonds by providing a more stable withdrawal pattern.

A review of models for predicting soil water dynamics during trickle irrigation

Designing drip irrigation systems involve selection of an appropriate combination of emitter discharge rate and spacing between emitters for any given set of soil, crop, and climatic conditions, as well as understanding the wetted zone pattern around the emitter. The exact shape of the wetted volume and moisture distribution will depend on many factors, including soil hydraulic characteristics, initial conditions, emitter discharge rate, application frequency, root characteristics, evaporation, and transpiration. Multi-dimensional nature of water flow, plant uptake and high frequency of water application increase the complexity in modelling soil moisture dynamics from trickle irrigation. Researchers used analytical methods, semi-analytical methods and numerical methods to Richards’ equation using certain boundary conditions to model the infiltration from point source irrigation for use in design, install, and manage of drip irrigation systems due to their merits over direct measurements. Others developed models based on Green-Ampt equation, empirical models using regression techniques/dimensional analysis techniques/moment approach techniques/artificial neural networks on this topic to describe infiltration from a point/line sources. A review on these models developed under each category is presented in this study. Other knowledge gaps identified include (a) effect of variations in initial moisture content and packing conditions, (b) precision in observing the wetting front and soil–water content, (c) validity of soil surface boundary conditions, (d) effect of crop root architecture and its withdrawal pattern for different input parameters, (e) effects of gravitational gradients, (f) stratification in the soils, and (g) impact of soil hysteresis. The review promotes better understanding of the soil water dynamics under point source trickle emitters and helps to identify topics for more emphasis in future modelling activity.

Work‐related behaviour and experience patterns of nurses

Goetz K., Beutel S., Mueller G., Trierweiler‐Hauke B. &amp; Mahler C. (2011) Work‐related behaviour and experience patterns of nurses. International Nursing Review59, 88–93Introduction. Nursing working conditions are characterized by heavy workloads and extensive responsibilities. The aim of our study was to report and to compare the actual conditions of work‐related behaviour and experience patterns of nurses working on intensive care units (ICUs) and intermediate care in a reference sample of nurses.Methods: The study was designed as a cross‐sectional survey with a sample of ICU and intermediate care nurses in one hospital in Germany and a reference sample of nurses (n = 378). Data were analysed regarding 11 health‐relevant dimensions and four behaviour patterns examined by the questionnaire ‘Work‐Related Behaviour and Experience Patterns’. Group comparison was evaluated with independent t‐test. The survey also collected demographic data.Results: In total, 86 of 158 questionnaires (54.4%) were returned. ICU and intermediate care nurses mainly differed in the health dimensions ‘career ambition’ and ‘satisfaction with work’, and had equal mean scores in ‘experiences of social support’. The most common pattern for the majority in our sample was the withdrawal pattern (46.8 %). 17.7% showed the burnout pattern. One third of our sample showed a healthy pattern (25.3%).Conclusions: It was possible to identify clear risk patterns for our sample of ICU and intermediate care nursing staff and to demonstrate that an essential aim should be to minimize the risk of burnout by strengthening nurses' individual, as well as work‐related resources by applying a salutogenic approach. Leadership should reinforce motivational aspects to prevent staff withdrawal and to keep nurses in the workforce.

Neural mechanism for generating and switching motor patterns of rhythmic movements of ovipositor valves in the cricket

In adult female crickets ( Gryllus bimaculatus), rhythmic movements of ovipositor valves are produced by contractions of a set of ovipositor muscles that mediate egg-laying behavior. Recordings from implanted wire electrodes in the ovipositor muscles of freely moving crickets revealed sequential changes in the temporal pattern of motor activity that corresponded to shifts between behavioral steps: penetration of the ovipositor into a substrate, deposition of eggs, and withdrawal of the ovipositor from the substrate. We aimed in this study to illustrate the neuronal organization producing these motor patterns and the pattern-switching mechanism during the behavioral sequence. Firstly, we obtained intracellular recordings in tethered preparations, and identified 12 types of interneurons that were involved in the rhythmic activity of the ovipositor muscles. These interneurons fell into two classes: ‘initiator interneurons’ in which excitation preceded the rhythmic contractions of ovipositor muscles, and ‘oscillator interneurons’ in which the rhythmic oscillation and spike bursting occurred in sync with the oviposition motor rhythm. One of the oscillator interneurons exhibited different depolarization patterns in the penetration and deposition motor rhythms. It is likely that some of the oscillator interneurons are involved in producing different oviposition motor patterns. Secondly, we analyzed oviposition motor patterns when the mecahnosensory hairs located on the inside surface of the dorsal ovipositor valves were removed. In deafferented preparations, the sequential change from deposition to withdrawal did not occur. Therefore, the switching from deposition pattern to withdrawal pattern is signaled by the hair sensilla that detect the passage of an egg just before it is expelled.

Residue analysis of sulfametazine in poultry product and its prevention

Sulfamethazine (SMZ) is a sulfonamide preparate widely used in feed to control and prevent diseases, and to promote growth. The use of sulfonamides may lead to residue formation, induce microbial resistance and suspected as a carcinogen. A serial study has been undertaken to investigate the withdrawal pattern of SMZ in meat and liver tissues in order to reduce residue of SMZ. A total of 80 day old chicken were divided into 4 groups consisting: (1) negative control without SMZ; (2) positive control dosing with SMZ for 35 days; (3) treatment-1 was dosed with SMZ for 28 days consecutively three times per week then ceased thereafter; and (4) treatment-2 was dosed with SMZ for 30 days consecutively three times per week then ceased thereafter. A field study revealed that some antimicrobials were detected in poultry meat samples, such as sulfamerazine ( = 2.52 ppb or nd – 12.62 ppb) and sulfamethazine ( = 0.02 ppb or nd – 0.09 ppb). An intragastric dosing of SMZ at 50 mg/kgBB did not affected body weight growth. Both positive control and treated groups showed haemorrhagic enteritis, nottling of capsular surface of liver and pale kidneys. Pathological changes were not found in negative control. Microscopically, pathological changes in liver, intestines and kidneys were found consistently in SMZ treatment. Withdrawal time of SMZ in broilers was between 5 to 10 days. Therefore to produce safe and healthy poultry products, sulfonamides treatment should be withdrawn 5 to 10 days prior to culling of birds and substitution of feed to unmedicated feed within this period is strongly recommended. Key Words : Residue, Sulfametazine, Poultry, Meat, Prevention

Negative affect states and cardiovascular disorders: a review and the proposal of a unifying biopsychosocial concept

Aim The purpose of this review was to study the relationships between negative affect states and cardiovascular disorders. Procedure The phenomenology of the negative affect states of depression, helplessness, hopelessness, vital exhaustion and grief is described. Their correlations with morbidity and mortality are analyzed. The physiological correlates of the affect states are pointed out. Finally, the reaction pattern of conservation–withdrawal according to Schmale [ Psychosom. Med. 20 (1958) 259–277] and Engel [ Internat. J. Psychoanalysis 43 (1962) 89–97] and its ontogenesis are outlined. This is a disengaging behavior pattern as opposed to the engaging fight–flight reaction pattern of Cannon [ Psychosom. Med. 19 (1957) 182–190]. The giving up complex, with its affects of helplessness and hopelessness, is explained. Conclusions The giving up complex in the context of the conservation–withdrawal pattern presents a biologically and developmentally sound conceptual basis for the understanding of the relationships of the negative affect states with cardiovascular disorders. This enables the integration of the concept of vital exhaustion, which has become the most promising operationalized instrument in psychosocial cardiovascular research.

Mid-Pleistocene extinction of deep-sea foraminifera in the North Atlantic Gateway (ODP sites 980 and 982)

The pulsed decline and eventual extinction of 51 species of elongate, cylindrical deep-sea benthic foraminifera (Stilostomellidae, Pleurostomellidae, and some Nodosariidae) occurred at intermediate water depths (1145–2168 m, Sites 980 and 982) in the northern North Atlantic during the mid-Pleistocene transition (MPT, 1.2–0.6 Ma). In the early Pleistocene, prior to their disappearance, these species comprised up to 20% of the total abundance of the benthic foraminiferal assemblage at 2168 m, but up to only 2% at 1145 m. The MPT extinction of 51 species represents ∼20% of the total benthic foraminiferal diversity at bathyal depths in the North Atlantic (excluding the myriad of small unilocular forms). The extinction rate during the MPT was approximately 10 species per 0.1 myr, being one or two orders of magnitude greater than normal background turnover rates of deep-sea benthic foraminifera. Comparison of the precise timings of declines and disappearances (= highest occurrences) of each species shows that they were often diachronous between the two depths. The last of these species to disappear in the North Atlantic was Pleurostomella alternans at ∼0.679 and ∼0.694 Ma in Sites 980 and 982, respectively, which is in good agreement with the previously documented global “ Stilostomella extinction” datum within the period 0.7–0.58 Ma. Comparison with similar studies in intermediate depth waters in the Southwest Pacific Gateway indicates that ∼61% of the extinct species were common to both regions, and that although the pattern of pulsed decline was similar, the precise order and timing of the extinction of individual species were mostly different on opposite sides of the world. Previous studies have indicated that this extinct group of elongate, cylindrical foraminifera lived infaunally and had their greatest abundances in poorly ventilated, lower oxygen environments. This is supported by our study where there is a strong positive correlation ( r = ∼+ 0.8) between the flux of the extinction group and low-oxygen/high organic input species (such as Uvigerina, Bulimina and Bolivina) during the MPT, suggesting a close relationship with lower oxygen levels and high food supply to the sea floor. The absolute abundance, flux, and number of the extinction group of species show a progressive withdrawal pattern with major decreases occurring in cold periods with high δ 13C values. This might be related to increasing chemical ventilation of glacial intermediate water.

Gradual enlargement of human withdrawal reflex receptive fields following repetitive painful stimulation

Dynamic changes in the topography of the human withdrawal reflex receptive fields (RRF) were assessed by repetitive painful stimuli in 15 healthy subjects. A train of five electrical stimuli was delivered at a frequency of 3 Hz (total train duration 1.33 s). The train was delivered in random order to 10 electrode sites on the sole of the foot. Reflexes were recorded from tibialis anterior, soleus, vastus lateralis, biceps femoris, and iliopsoas (IL). The RRF changes during the stimulus train were assessed during standing with even support on both legs and while seated. The degree of temporal summation was depending on stimulation site. At the most sensitive part of the RRF, a statistically significant increase in reflex size was seen after two stimuli while four stimuli were needed to observe reflex facilitation at less sensitive electrode sites. Hence, the region from which reflexes could be evoked using the same stimulus intensity became larger through the train, that is, the RRF was gradually expanding. Reflexes evoked by stimuli four and five were of the same size. No reflex facilitation was seen at other stimulus sites outside the RRF. In all muscles except in IL, the largest reflexes were evoked when the subjects were standing. In the ankle joint, the main withdrawal pattern consisted of plantar flexion and inversion when the subjects were standing while dorsi-flexion was prevalent in the sitting position. Up to 35° of knee and hip flexion were evoked often leading to a lift of the foot from the floor during standing. In conclusion, a gradual expansion of the RRF was seen in all muscles during the stimulus train. Furthermore, the motor programme task controls the reflex sensitivity within the reflex receptive field and, hence, the sensitivity of the temporal summation mechanism.

Methamphetamine-associated burn injuries: a retrospective analysis.

Methamphetamine production and use has increased dramatically during the past 10 years. Methamphetamine production requires combining hazardous and volatile chemicals that expose the manufacturer to burn injuries from explosions and chemical spills. We sought to review the epidemiology of burn injuries in a rural burn center secondary to the use of amphetamine or methamphetamine and/or the manufacture of methamphetamine. Review of the records of 507 patients who were admitted to our burn unit from December 1, 1998, to December 31, 2001, revealed 34 patients who were involved in the use of amphetamines or methamphetamines and/or the manufacture of methamphetamine. Thirty-one patients tested positive for either amphetamine (n = 2) or methamphetamine (n = 29) on routine admission urine drug screens. Twenty of these patients were involved in the manufacture of methamphetamines. Three additional patients were identified as methamphetamine manufacturers but tested negative for the use of methamphetamines. The mean age of the study population was 31.88 +/- 7.65 years, with a male:female ratio of 10.3:1. The average burn size was 18.86 +/- 20.72, with the majority secondary to flame (n = 26). Patient burn admission histories were vague, and the patient's involvement in the manufacture of methamphetamine was often only later confirmed by media, the fire marshal, family members, or the patient. Fifteen patients showed the usual withdrawal pattern of agitation and hypersomnolence, with seven patients requiring detoxification with benzodiazepines. Two were admitted acutely to the psychiatric ward for uncontrollable agitation. Eighteen patients were offered chemical dependency treatment, and two completed therapy. There was one mortality. The mean cost per person was US 77,580 dollars (range, US 112 dollars - US 426,386 dollars). The increasing use of and manufacture of methamphetamine presents new challenges for the burn team because these patients can become violent and frequently need assistance with detoxification. Routine drug screens are mandatory in identifying methamphetamine use to alert burn unit personnel to particular management problems and target individuals who may be receptive to drug rehabilitation.