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Selected AbstractsDiverse alcohol drinking patterns in 20 African countriesADDICTION, Issue 7 2009Thomas Clausen ABSTRACT Aims This paper describes drinking patterns in 20 African countries, exploring the extent of abstention, heavy occasional drinking and daily light drinking and how these aspects of drinking are inter-related. Design and participants Data were collected as part of the World Health Survey in 2002,04 and comprise national representative data sets from 20 African countries. A cross-sectional survey of 77 165 adults aged 18 years and older were undertaken by face-to-face interviews in respondent households. Measures Drinking behaviour was assessed in terms of life-time abstention and the following measures over the 7 days immediately preceding interview: high consumption (15 or more drinks); heavy drinking occasions (five or more standard units at at least one session) and daily light drinking (one or two drinks daily). Findings In four countries (Comoros, Mali, Mauritania and Senegal), virtually all respondents were life-time abstainers. The prevalence of current drinkers (previous week) did not exceed one-third in any country. Among current drinkers the prevalence of heavy drinking varied between 7% and 77% and the prevalence of daily light drinkers varied between 0% and 21%. Overall drinking patterns varied significantly between and within the examined African countries. Conclusions African drinking patterns are diverse, and although life-time abstinence dominates in African countries, a single typical pattern of drinking for the African continent, such as the alleged ,all-or-none' pattern, was not observed. [source] Use and toxicity of complementary and alternative medicines among emergency department patientsEMERGENCY MEDICINE AUSTRALASIA, Issue 5-6 2004David McD Taylor Abstract Objective:, To determine the prevalence and type of complementary and alternative medicines (CAM) used by ED patients, to identify patient subgroups more likely to use CAM, the conditions for which they were taken, and the prevalence of side-effects and toxicity associated with CAM use. Methods:, This was an analytical cross-sectional survey of patients at a large tertiary referral ED. Consenting patients completed a specifically designed study questionnaire, in their preferred language if required. Information was collected on CAM use on the day of presentation and within the previous week and previous year. Results:, Four hundred and four patients were enrolled (participation rate 97.1%). Fifty (12.4%, 95% CI 9.4, 16.1) patients had taken a CAM on the day of presentation, 203 (50.2%, 95% CI 45.3, 55.2) within the previous week and 275 (68.1%, 95% CI 63.2, 72.5) within the previous year. CAM users were significantly younger, better educated and more likely to be female than non-CAM users (P < 0.01). 103 different CAM had been taken for a wide variety of reasons. Side-effects were experienced in 53 of the 1182 CAM courses taken (side-effect rate of 4.5%). One patient presented suffering specifically from CAM toxicity. Conclusion:,, Complementary and alternative medicines are used by a considerable proportion of ED patients. The potential for side-effects, toxicity and interaction with traditional medication indicates the need for consideration of CAM use in patient assessment. [source] Leptin is associated with craving in females with alcoholismADDICTION BIOLOGY, Issue 3-4 2004T Kraus The appetite and weight regulating peptide leptin was associated recently with alcohol craving during withdrawal. Nevertheless, correlations were only significant with craving displayed on the visual analogue scale for maximum craving during the previous week (VAS), and not if assessed with the highly validated Obsessive Compulsive Drinking Scale (OCDS). The objective of the following study, therefore, is to elucidate further the associations between the leptin system and craving concepts during alcohol withdrawal. A sufficiently large sample size should allow multiple statistical subgroup and confounder analyses. We prospectively investigated 102 chronic alcoholic inpatients (23 females, 79 males) during withdrawal on days 0 (admission), 1, 2 and days 7,-,10. In addition to the statistical analysis of the total sample, females and males were to be analysed separately. For detecting associations between leptin levels and craving scores multiple regression analysis was performed. Plasma leptin levels were determined, and craving for ethanol was assessed by both the OCDS and the VAS. Leptin plasma levels significantly increased during alcohol withdrawal compared to day 0, while all craving scores decreased. Body mass corrected leptin plasma levels predicted craving on day 0 in the OCDS total score (R ,=,0.55, F ,=,7.91, df,=,1.19, p ,<,0.05) and in the OCDS obsessive subscore (R ,=,0.57, F <,=,8.48, df,=,1.19, p ,<,0.05) in females. Neither in males nor in the total population did multiple regression analysis reveal any significant results. Leptin levels seem to change during inpatient alcohol withdrawal. In a multivariate model, correlations between leptin levels and the highly validated craving scores of the OCDS can only be assumed in females. Hence, gender differences have to be taken into account when searching for neurobiological models of alcohol craving. [source] A child with spider bite and glomerulonephritis: a diagnostic challengeINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 4 2000Jennifer M. Lung MD A previously healthy 7-year-old white boy presented to St. Louis Children's Hospital with a 1-day history of headache, malaise, temperature of 38.7 °C, and a progressively erythematous, tender calf with central dusky purpura. On the morning of admission, his mother noticed a 2-mm crust on the patient's right calf with a 3-cm × 3-cm area of surrounding erythema. No history of recent trauma or bite was obtained. He had suffered two episodes of nonbloody, nonbilious emesis during the last day. In addition, over the previous 12 h, he presented brown urine without dysuria. His mother and brother had suffered from gastroenteritis over the previous week without bloody diarrhea. On initial physical examination, there was a 6-cm × 11-cm macular tender purpuric plaque with a central punctum on the right inner calf, which was warm and tender to the touch, with erythematous streaking towards the popliteal fossa ( Fig. 1). The inguinal area was also erythematous with tender lymphadenopathy and induration, but without fluctuance. Laboratory studies included an elevated white blood cell count of 20,800/,L with 6% bands, 86% segs, and 7% lymphocytes, hemoglobin of 12.5 g/dL, hematocrit of 35.1%, and platelets of 282,000/,L. The prothrombin time/activated partial tissue thromboplastin was 10.4/28.0 s (normal PT, 9.3,12.3 s; normal PTT, 21.3,33.7 s) and fibrinogen was 558 mg/dL (normal, 192,379 mg/dL). Urinalysis showed 1+ protein, 8,10 white blood cells, too numerous to count red blood cells, and no hemoglobinuria. His electrolytes, blood urea nitrogen (BUN), and creatine were normal. The urine culture was negative. Blood culture after 24 h showed one out of two bottles of coagulase negative Staphylococcus epidermidis. Figure 1. (A) 7-year-old boy with painful purpura of the calf The patient's physical examination was highly suggestive of a brown recluse spider bite with surrounding purpura. Over the next 2 days, the surrounding rim of erythema expanded. The skin within the plaque cleared and peeled at the periphery. The coagulase negative staphylococci in the blood culture were considered to be a contaminant. Cefotaxime and oxacillin were given intravenously. His leg was elevated and cooled with ice packs. The patient's fever resolved within 24 h. The lesion became less erythematous and nontender with decreased warmth and lymphadenopathy. The child was discharged on Duricef for 10 days. Because the patient experienced hematuria rather than hemoglobinuria, nephritis was suggested. In this case, poststreptococcal glomerulonephritis was the most likely cause. His anti-streptolysin-O titer was elevated at 400 U (normal, <200 U) and C3 was 21.4 mg/dL (normal, 83,177 mg/dL). His urine lightened to yellow,brown in color. His blood pressure was normal. Renal ultrasound showed severe left hydronephrosis with cortical atrophy, probably secondary to chronic/congenital ureteropelvic junction obstruction. His right kidney was normal. [source] Having a child with asthma,Quality of life for Jordanian parentsINTERNATIONAL JOURNAL OF NURSING PRACTICE, Issue 6 2009Nemeh Al-Akour DSN This study was conducted to assess the quality of life (QoL) of Jordanian parents of children with asthma and its associated factors. Three hundred and twenty-six parents of 200 children participated in the study. The Pediatric Asthma Caregivers' Quality of Life Questionnaire (PACQLQ) was used to measure how parents of children with asthma disease impaired their daily life during the previous week on two domains ,activity limitations' and ,emotional function'. In this study, parents of children with asthma scored their QoL during the past week moderately to the positive end of the scale but they scored more limitations in the domain of activities than in emotions. Parents in the same family scored activity domain fairly similar and there was a significant difference in their scoring of total emotional function. Parents with older children, living in the rural areas, mothers of children with mild asthma were associated with higher QoL. Children received needed daily asthma medication during the preceding week. Asthma medication might mean to the parents that the child was getting the best possible treatment. Further studies to identify the factors that influence QoL of parents of children with asthma in Jordan are needed. [source] Quality of life in Jordanian children with asthmaINTERNATIONAL JOURNAL OF NURSING PRACTICE, Issue 6 2008Nemeh Al-Akour RN MSN DNSc The purpose of this study was to describe how Jordanian children with asthma experience their quality of life (QoL). Two hundred children with asthma (34% girls and 66% boys) participated in the study. The Paediatric Asthma Quality of Life Questionnaire was used to measure how children with asthma disease impaired their daily life during the previous week on three domains: ,activity limitations', ,symptoms' and ,emotional function'. The main finding of this study was that children with asthma scored their QoL towards the negative end of the scale, but they scored more limitations in the domain of activities than in emotions and symptoms. Children reported that the most restricted activity was their ability to run. Younger children, being a girl and living in the rural areas, were associated with lower QoL. The children in the present study might not comply with their health regimen, and this might gave a darker view of the daily life of children with asthma. Further studies of Jordanian children and their QoL were suggested to identify and support the factors which influence QoL of children with asthma and other chronic diseases in Jordan. [source] Bullying among mentally-ill patients detained in a high-secure hospital: an exploratory study of the perceptions of staff and patients into how bullying is definedAGGRESSIVE BEHAVIOR, Issue 5 2006Jane L. Ireland Abstract The present study is the first to explore patient-to-patient bullying within a secure psychiatric hospital housing mentally-ill patients. Its main aim was to provide an outline of the perceptions held by both patients and staff with regards to patient-to-patient bullying as opposed to providing an objective study of bullying. The total sample comprised 104 participants, 44 patients and 60 staff. These were sampled from wards housing male patients and wards housing female patients. All participants took part in a semi-structured interview based on that developed by Ireland and Ireland [2003] and Ireland [2005, 2004]. One quarter of participants stated they had seen a patient being bullied in the previous week, with staff perceiving a higher extent of bullying than patients. Differences between wards were minimal. It was predicted that theft-related bullying would be reported most frequently, that staff would identify a wider range of bullying behaviours than patients and that direct forms of aggression would be identified more readily as bullying than indirect forms. All predictions were supported. Problems in attempting to obtain a definition of bullying were also identified, with participants operating broader definitions than those found in the school-based literature. For example, bullying was not generally considered a repeated form of aggression, the severity of the aggression or provocative behaviour of the victim were not defining features, and it was felt bullying could be accidental. In summary, the current study highlights how patient-to-patient bullying does occur in services housing mentally-ill patients and that researching the behaviour may require the adoption of broader hospital-specific definitions of bullying. Aggr. Behav. 32:1,13, 2006. © 2006 Wiley-Liss, Inc. [source] Nature, extent, and causes of bullying among personality-disordered patients in a high-secure hospitalAGGRESSIVE BEHAVIOR, Issue 3 2004Jane L. Ireland Abstract The present study explored the perceptions and experiences of the nature, extent and causes of bullying among personality-disordered patients, with a subsidiary aim of exploring differences in perceptions between staff and patients. The sample was selected from the Personality Disorder Unit of a high secure hospital. The total sample consisted of 60 participants, 30 patients and 30 staff. Participants engaged in a semi-structured interview based on that developed by Brookes [1993] and modified by Ireland and Archer [1996] and Ireland [2002a]. The interview assessed their perceptions and experiences of patient-to-patient bullying. One fifth of patients and staff reported that they had seen a patient being bullied in the previous week. One-fifth of patients reported that they had been bullied in the previous week and less than one tenth reported that they had bullied others. The most frequent types of bullying reported were theft-related, verbal abuse, being made to do chores, physical assaults and intimidation. One fifth of the sample reported that sexual abuse took place. Victims were generally perceived to be ,easy targets' that were vulnerable, either physically or emotionally. Staff identified a wider range of victim types than patients. The results highlight how patient-to-patient bullying does occur and is an important issue worthy of further research. A number of similarities were found between the current findings and those of prison-based research suggesting that both hospitals and prisons share a number of environmental similarities that help to explain why bullying takes placed in secure forensic settings. Aggr. Behav. 30:229,242, 2004. © 2004 Wiley-Liss, Inc. [source] Risk profiles for non-adherence to antipsychotic medicationsJOURNAL OF PSYCHIATRIC & MENTAL HEALTH NURSING, Issue 8 2008T. V. MCCANN rmn rgn phd ma ba dipnurs (lond) rnt rcnt Poor adherence to medications is common in individuals with schizophrenia, and can lead to relapse and re-hospitalization. This paper presents the findings of an Australian study of the factors affecting antipsychotic medication taking in individuals with schizophrenia. The Factors Influencing Neuroleptic Medication Taking Scale was used with a non-probability sample of mental health service users. Ethics approval was obtained from a university and a hospital ethics committee. Data were analysed using spss version 15. Most participants had insight into their illness and were aware of the stigma of mental illness. Around 70% experienced annoying side effects, while nearly half admitted alcohol consumption. About one-fifth admitted they had missed taking medications during the previous week. Significant others played a variable role in medication taking. Over 80% were satisfied with their relationships with health professionals, but were less satisfied with access to these professionals, especially psychiatrists. Logistic regression analysis showed that age, impact of medication side effects, and access to psychiatrists were independent predictors of medication omission. It is argued that medication taking is a complex issue, which needs to be taken into consideration in health professional training and measures to promote adherence. [source] Adolescent Perceptions of Conflict in Interdependent and Disengaged FriendshipsJOURNAL OF RESEARCH ON ADOLESCENCE, Issue 3 2002Shmuel Shulman Interdependent and disengaged friendships in a middle-class sample of suburban Israeli adolescents were examined for differences in reports of conflict behavior. A total of 194 (100 females, and 94 males) close, reciprocal friends participated in a joint problem-solving task used to categorize friendships. Interdependent friends balanced closeness and individuality by cooperating on the task, whereas disengaged friends emphasized individuality by working independently on the task. In separate interviews, these friends recounted their most important conflict from the previous week. Older adolescents (M= 17.4 years) reported more conflicts over private disrespect than did younger adolescents (M= 12.7 years), whereas younger adolescents reported more conflicts over public disrespect and undependability than did older adolescents. Differences between friendship types in conflict initiation, negative affect, and relationship impact were found among older adolescents but not younger adolescents; differences in conflict resolutions were found in both age groups. In contrast to disengaged friends, interdependent friends were better able to manage conflicts in a manner that emphasized relationship harmony over individual gain. [source] Trends and Determinants of Alcohol Consumption in Portugal: Results From the National Health Surveys 1995 to 1996 and 1998 to 1999ALCOHOLISM, Issue 1 2005Pedro Marques-Vidal Background: There is very little information on trends and determinants of alcohol consumption in the Portuguese population, which is usually characterized by high wine consumption. Methods: A cross-sectional studies was conducted in 1995/1996 and 1998/1999 in a representative sample of 0.5% of the mainland Portuguese population (49,768 participants in 1995/1996 and 48,606 in 1998/1999), aged 15 years or more. Alcohol consumption was assessed by asking whether the participants had consumed alcohol in the previous week and how many drinks of wine/beer/whiskey/Port wine they consumed on average during that week. Results: Prevalence of reported alcohol consumption decreased slightly between 1995/1996 and 1998/1999 (men: 65.7 vs. 64.0%, p < 0.001; women: 26.9 vs. 26.0%, p < 0.001). Among drinkers, the most frequently consumed alcoholic beverage was wine, followed by beer, whiskey, and Port wine. The amount of alcohol and wine consumed decreased in both sexes, whereas the amount of beer, whiskey, and Port wine consumed increased in men and the increase in beer consumption was borderline significant in women (p= 0.056). In both sexes, participants <50 years of age tended to consume less wine and more beer, whiskey, and Port wine than their older counterparts. Also, higher education was related to a higher frequency of alcohol consumption, whereas smoking was related to a lower consumption of wine odds ratio (OR): 0.69 (95% confidence interval CI: 0.62,0.77) for men and OR: 0.76 (95% CI: 0.61,0.95) for women and a higher consumption of beer OR: 1.43 (95% CI: 1.33,1.54) for men and OR: 2.13 (95% CI: 1.84,2.42) for women and whiskey OR: 1.28 (95% CI: 1.21,1.35) for men and OR: 2.61 (95% CI: 2.25,3.02) for women. Conclusions: The pattern of alcohol consumption is changing in Portugal: the prevalence of drinkers is decreasing, and younger generations are shifting from wine to beer and spirits. Educational level seems to be a powerful mediator in the choice of alcoholic beverage. [source] Consequences of frequent nocturnal gastro-oesophageal reflux disease among employed adults: symptom severity, quality of life and work productivityALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 4 2007R. W. DUBOIS Summary Background Effects of frequent nocturnal symptoms of gastro-oesophageal reflux disease (GERD-FNS) on health-related quality of life (HRQOL) and work productivity are not well documented. Aim To assess symptom severity, production loss, and HRQOL among employed adults with and without GERD-FNS. Methods Using several validated outcome measures in a web survey design, GERD was pre-specified as GERD Symptom and Medication Questionnaire score >9, and ,1 episode of heartburn or acid regurgitation during the preceding week. GERD-FNS patients were those reporting ,2 symptom-nights during the previous week; their outcomes were compared with those of patients having minimal or no nocturnal symptoms (GERD-NNS) and vs. non-GERD controls. Results Data were collected from 1002 GERD patients (476 GERD-FNS, 526 GERD-NNS) and 513 controls. Severe symptoms were more common, sleep abnormalities were more frequent (P < 0.0001) and SF-36 scores lower (P < 0.05, all scores) among GERD-FNS patients vs. GERD-NNS patients. GERD-related work loss was greater among those with GERD-FNS vs. GERD-NNS (P < 0.0001). Work loss and functional limitations were more pronounced when comparing GERD-FNS cases vs. non-GERD controls. Conclusion Employed adults with frequent nocturnal GERD report more severe symptoms, and are associated with impaired sleep, HRQOL and work productivity compared with controls and patients with minimal or no nocturnal symptoms. [source] Suicidal ideation and associated factors among community-dwelling elders in TaiwanPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 4 2005YUNG-CHIEH YEN md Abstract, The purpose of the present study was to explore the suicidal ideation of community-dwelling elderly and the factors associated with their intention to commit suicide. Using a multilevel stratified sampling strategy, 1000 elderly subjects were recruited (aged 65,74 years old) in Taiwan during the year 2001. The degree of depression and its correlates were assessed. Suicidal ideation was measured by asking respondents if they had had any suicidal thoughts in the previous week. In all, 16.7% of respondents reported suicidal ideation within the past week; its occurrence was related to sex, religious belief, employment status, marital status, average family monthly income, physical health status, depressive symptoms, and community activity participation. Further multivariate logistic regression revealed that, aside from depressive symptoms and a lower level of education, no community participation in the past 6 months was significantly associated with the appearance of suicidal ideation. The prevalence of suicidal ideation among the elderly in Taiwan is higher than in Western countries. Participation in social activities is negatively associated with elderly suicidal ideation. The dimension of social participation deserves further exploration and should be considered in community mental health promotion interventions for elderly people. [source] Art therapy improved depression and influenced fatigue levels in cancer patients on chemotherapyPSYCHO-ONCOLOGY, Issue 11 2007Gil Bar-Sela Abstract Introduction: Cancer patients are particularly vulnerable to depression and anxiety, with fatigue as the most prevalent symptom of those undergoing treatment. The purpose of this study was to determine whether improvement in depression, anxiety or fatigue during chemotherapy following anthroposophy art therapy intervention is substantial enough to warrant a controlled trial. Material and methods: Sixty cancer patients on chemotherapy and willing to participate in once-weekly art therapy sessions (painting with water-based paints) were accrued for the study. Nineteen patients who participated in ,4 sessions were evaluated as the intervention group, and 41 patients who participated in ,2 sessions comprised the participant group. Hospital Anxiety and Depression Scale (HADS) and the Brief Fatigue Inventory (BFI) were completed before every session, relating to the previous week. Results: BFI scores were higher in the participant group (p=0.06). In the intervention group, the median HADS score for depression was 9 at the beginning and 7 after the fourth appointment (p=0.021). The median BFI score changed from 5.7 to 4.1 (p=0.24). The anxiety score was in the normal range from the beginning. Conclusion: Anthroposophical art therapy is worthy of further study in the treatment of cancer patients with depression or fatigue during chemotherapy treatment. Copyright © 2007 John Wiley & Sons, Ltd. [source] Factors associated with health-related quality of life among low-compliant asthmatic adults in Korea,RESEARCH IN NURSING & HEALTH, Issue 2 2009Ja Yun Choi Abstract This cross-sectional descriptive study was conducted to identify the factors associated with health-related quality of life (HRQoL) in low-compliant Korean adults with asthma. The sample consisted of 178 patients referred by a physician to the education clinic at a University hospital in Korea. Stepwise multiple regression analysis revealed that previous hospital admissions, recent asthma-related symptoms within the previous week, lower peak expiratory flow rate, and lower level of asthma knowledge were independently associated with lower HRQoL and accounted for 46% of the total variance. Health care providers should focus on these factors to increase perceptions of HRQoL among low-compliant patients. Interventional strategies need to be developed to emphasize the importance of compliance to the self-monitoring regimen and management protocols. © 2008 Wiley Periodicals, Inc. Res Nurs Health 32:140,147, 2009 [source] Hepatitis C in the workplace: a survey of occupational health and safety knowledge and practice in the beauty therapy industryAUSTRALIAN AND NEW ZEALAND JOURNAL OF PUBLIC HEALTH, Issue 3 2004Madeleine J. Murtagh Objective:To examine current knowledge and practice of occupational health and safety (OH&S) regarding hepatitis C in beauty therapy practice. Methods: A questionnaire was sent to all beauty therapy practices identified through the Telstra Yellow Pages and distributed via beauty therapy product agencies. Results: 119 questionnaires were completed by employers and employees in 99 beauty therapy practices in metropolitan Adelaide. Beauty therapists reported carrying out many practices that had exposed them to blood in the past. More than 80% of the procedures carried out by beauty therapists in the previous week were reported to have led to exposure to blood. 39.5% of respondents had not received information about OH&S practices related to blood spills and 77.5% of respondents had received no OH&S information about hepatitis C. Knowledge of hepatitis C and its transmission was poor, with 62% of respondents incorrectly identifying the prevalence of hepatitis C and respondents incorrectly identifying sneezing (28%), kissing (46%) and sharing coffee cups (42%) as a modes of transmission. 80% of beauty therapy practices had no OH&S representative. Conclusion: Beauty therapy practice can expose both operator and client to blood and is therefore a potential site for the transmission of blood-borne diseases including hepatitis C. OH&S information is inadequate in this industry and knowledge of hepatitis C is poor. Implications: Health promotion information about hepatitis C and OH&S practice to prevent transmission of blood-borne diseases is required. [source] Pain in children with cerebral palsy: a cross-sectional multicentre European studyACTA PAEDIATRICA, Issue 3 2010KN Parkinson Abstract Aim:, To determine the prevalence and associations of self-reported and parent-reported pain in children with cerebral palsy (CP) of all severities. Method:, Cross-sectional design using a questionnaire; analysis using ordinal regression. Children aged 8,12 years were randomly selected from population-based registers of children with CP in eight European regions; a further region recruited 75 children from multiple sources. Outcome measures were pain in the previous week among children who could self-report and parents' perception of their child's pain in the previous 4 weeks. Results:, Data on pain were available from 490 children who could self-report and parents of 806 children (those who could and could not self-report). The estimated population prevalence of self-reported pain in the previous week was 60% (95% CI: 54,65%) and that of parent-reported pain in the previous 4 weeks was 73% (95% CI: 69,76%). In self-reporting children, older children reported more pain but pain was not significantly associated with severity of impairment. In parent reports, severity of child impairment, seizures and parental unemployment were associated with more frequent and severe pain. Conclusion:, Pain in children with CP is common. Clinicians should enquire about pain and consider appropriate physical, therapeutic or psychological management. [source] Evolution and dynamics of summertime blocking over the Far East and the associated surface Okhotsk highTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 599 2004Hisashi Nakamura Abstract Time evolution and dynamics of an upper-level blocking ridge over the Far East and the associated surface high over the Sea of Okhotsk that give rise to abnormal summertime coolness over eastern Japan are investigated through a composite analysis applied to distinct surface high events. The formation mechanism and vertical structure of the blocking differ fundamentally between May and July, attributable to seasonal changes in the jet structure, storm-track activity over the Far East and the land,sea thermal contrast within the Okhotsk region. In May, forcing from migratory eddies is strong enough for precursory anticyclonic anomalies retrograding slowly over the North Pacific to develop into a blocking ridge. The ridge remains equivalent barotropic under the weak land,sea thermal contrast in the Okhotsk region. In contrast, the eddy forcing is no longer the primary factor for the blocking formation in July, in the presence of the weakened and split westerlies. Rather, the propagation of a stationary Rossby wave packet that has emanated from precursory anticyclonic anomalies over northern Europe stagnates over the Far East, and the subsequent local breaking of the packet leads to the blocking formation. In a particular case in July 1993, a wave packet involved in blocking formation could be traced back as far upstream as the east coast of North America over the two previous weeks. Acting on the strong thermal contrast in July between the cool sea surface and a warm land mass to the west, the anomalous surface easterlies induced by the blocking ridge can build up a cold surface anticyclone through cold advection, rendering the blocking anomalies distinctly baroclinic. Copyright © 2004 Royal Meteorological Society [source] | |||||||||||||