Observation of strong nonlinear interactions in parametric down-conversion of X-rays into ultraviolet radiation.

Nonlinear interactions between X-rays and long wavelength radiation can be used as a powerful atomic-scale probe for light-matter interactions and for properties of valence electrons. However, reported X-ray nonlinear effects were small and their observations required tremendous efforts. Here we report the observation of strong nonlinearities in parametric down-conversion (PDC) of X-rays to long wavelength radiation in gallium arsenide and lithium niobate crystals, with efficiencies about 4 orders of magnitude stronger than the efficiencies measured in any material studied before. Furthermore, we show that the efficiency in the ferroelectric phase of strontium barium niobite is two orders of magnitude stronger than in its paraelectric phase. This observation suggests that the lack of inversion symmetry is the origin for the strong observed nonlinearity. Additionally, we demonstrate the ability to use the effect for the investigation of the spectral response of non-centrosymmetric materials at wavelengths ranging from infrared to soft X-rays.

Molecular detection of zoonotic bartonellae (B. henselae, B. elizabethae and B. rochalimae) in fleas collected from dogs in Israel.

Fleas represent an acknowledged burden on dogs worldwide. The characterization of flea species infesting kennel dogs from two localities in Israel (Rehovot and Jerusalem) and their molecular screening for Bartonella species (Rhizobiales: Bartonellaceae) was investigated. A total of 355 fleas were collected from 107 dogs. The fleas were morphologically classified and molecularly screened targeting the Bartonella 16S-23S internal transcribed spacer (ITS). Of the 107 dogs examined, 80 (74.8%) were infested with Ctenocephalides canis (Siphonaptera: Pulicidae), 68 (63.6%) with Ctenocephalides felis, 15 (14.0%) with Pulex irritans (Siphonaptera: Pulicidae) and one (0.9%) with Xenopsylla cheopis (Siphonaptera: Pulicidae). Fleas were grouped into 166 pools (one to nine fleas per pool) according to species and host. Thirteen of the 166 flea pools (7.8%) were found to be positive for Bartonella DNA. Detected ITS sequences were 99-100% similar to those of four Bartonella species: Bartonella henselae (six pools); Bartonella elizabethae (five pools); Bartonella rochalimae (one pool), and Bartonella bovis (one pool). The present study indicates the occurrence of a variety of flea species in dogs in Israel; these flea species are, in turn, carriers of several zoonotic Bartonella species. Physicians, veterinarians and public health workers should be aware of the presence of these pathogens in dog fleas in Israel and preventive measures should be implemented.

The neuropsychological profile of patients with 3-methylglutaconic aciduria type III, Costeff syndrome.

Costeff syndrome is a rare genetic neuro-ophthalmological syndrome consisting of early-onset bilateral optic atrophy along with a progressive complex motor disorder with elevated levels of urinary 3-methylglutaconic acid and 3-methylglutaric acid. While borderline to mild cognitive deficits have been considered to be common in patients with this syndrome, a comprehensive cognitive assessment has never been performed. The aim of the current study was to explore the cognitive profile associated with Costeff syndrome. Sixteen adult patients diagnosed with Costeff syndrome were administered a neuropsychological test battery that was composed of standardized verbal tests adapted for the blind. General intelligence ranged from average to borderline, with a group mean consistent with intact general cognitive functioning (VIQmean = 85, z = -1) in the low-average range of the general population. The auditory immediate and delayed memory indexes were in the average range and were significantly higher than the general cognitive functioning, whereas the working memory index was significantly lower than the general cognitive functioning. Adult patients with Costeff syndrome have intact global cognition and learning abilities and strong auditory memory performance. © 2015 Wiley Periodicals, Inc.

Impact of conversion from an open ward design paediatric intensive care unit environment to all isolated rooms environment on incidence of bloodstream infections and antibiotic resistance in Southern Israel (2000 to 2008).

We studied the epidemiology, microbiology, clinical aspects and outcome of bloodstream infections (BSI) in a tertiary paediatric intensive care unit. All BSI episodes were prospectively identified and analysed. The paediatric intensive care unit moved in 2006 from an open-plan unit to a new (all single room) unit. Three hundred and fifty-three BSI episodes occurred in 299 of 4162 patients. Overall, BSI incidence was 85 per 1000 hospitalised children. Fewer BSI episodes occurred during the last two years of the study (2007 to 2008), compared with 2000 to 2006 (70 of 1061 admissions, 6.5% versus 283 of 3101 admissions, 9.1%, respectively, P=0.01). There were 127 of 340 (37.4%) community-acquired and 213 of 340 (62.6%) nosocomial BSI episodes (31 of 1000 and 51 of 1000, respectively). Nosocomial BSI episodes decreased during 2007 to 2008 versus 2000 to 2006 (37.7% versus 55.8%, P=0.03). In 448 instances, pathogens were isolated, 231 (52%) Gram-positive and 188 (42%) Gram-negative. Coagulase-negative Staphylococci, S. pneumoniae and S. aureus (41.1%, 19.9% and 11.7%, respectively) were the most common Gram-positive and Enterobacteriaceae spp. the most frequent Gram-negative organisms (45.2%, of them Klebsiella spp. and E. coli 40% and 29.4%, respectively). A significant decrease was recorded during 2007 to 2008 in Enterobacteriaceae resistance to piperacillin, gentamicin and ciprofloxacin. Thirty of 299 (10%, 9 with S. pneumoniae-BSI) patients died. A significant decrease in BSI and nosocomial incidence and Enterobacteriaceae spp. antibiotic resistance was recorded following the conversion of the paediatric intensive care unit from an open ward to an all isolated rooms environment.

Changes in daily leptin, ghrelin and adiponectin profiles following a diet with carbohydrates eaten at dinner in obese subjects.

BACKGROUND AND AIMS: Our recently published randomised clinical trial evaluated the effect of a low-calorie diet with carbohydrates eaten at dinner. This dietary pattern led to lower hunger scores, and better anthropometric, biochemical and inflammatory outcomes compared to a standard low-calorie diet. In the same study, changes in diurnal secretion patterns of leptin, ghrelin and adiponectin were investigated. METHODS AND RESULTS: Seventy-eight police officers (body mass index (BMI) > 30) were randomly allocated to experimental (carbohydrates at dinner) or control weight loss diets for 6 months. Sixty-three subjects finished the programme. On days 0, 7, 90 and 180 blood samples and hunger scores were collected every 4 h from 8:00 to 20:00. Hormonal profiles were available for 39. The dietary manipulation led to changes in daylight hormonal profiles in the experimental group. Leptin's secretion curve became convex, with a nadir later in the day (significant difference compared to baseline at morning and evening, p = 0.023, p = 0.021, respectively). Ghrelin's secretion curve became concave, peaking only in the evening hours. Adiponectin's curve was elevated only after the experimental diet (significant difference compared to baseline at afternoon, p = 0.044). CONCLUSIONS: We propose that a low-calorie diet with carbohydrates eaten at dinner can modulate daytime hormonal profiles. Taken together with our earlier results, we believe this diet regime may prevent mid-day hunger, better support weight loss and improve metabolic outcomes compared to conventional weight loss diets. The trial is registered at controlled-trials.com, ISRCTN37829376, December 2009.

Bulimia nervosa and substance use disorder: similarities and differences.

The purpose of this study was to compare bulimia nervosa (BN) and substance use disorders (SUD) in cognitive-motivational terms. The cognitive orientation theory was used as a framework for testing the hypothesis that the commonality between BN and SUD consists of a similar motivational disposition for eating disorders, rather than for addiction, as was previously claimed. It was expected that BN and SUD patients would differ from controls but not from each other. The participants were 31 BN, 20 SUD, and 20 healthy controls. They were administered questionnaires for assessing anxiety, depression, addiction and the cognitive orientation for eating disorders. On most parameters BN and SUD scored higher than controls but did not differ from each other except in norm beliefs. Treatment of BN should consider the similarity of BN to SUD in the pathological tendency for eating disorders.

Early onset pneumococcal sepsis in children hospitalized for noninfectious life-threatening events.

During a 13-year period 9 patients admitted to a pediatric intensive care unit for life-threatening noninfectious conditions developed pneumococcal sepsis within 48 h of admission. All patients were Bedouins, a population group characterized by high prevalence of respiratory carriage of Streptococcus pneumoniae. In populations with high carriage rates of S. pneumoniae, critically ill children appear to be at increased risk of pneumococcal sepsis.

Use of the UFOV to evaluate and retrain visual attention skills in clients with stroke: a pilot study.

OBJECTIVE: The objective of this pilot study was to examine the use of a visual attention analyzer in the evaluation and retraining of useful field of view in clients with stroke. METHOD: Fifty-two clients with stroke referred to a driving evaluation service were evaluated with a visual attention analyzer referred to as the UFOV. The UFOV assesses three aspects of visual attention: processing speed, divided attention, and selective attention. Seven participants were retested to determine the test-retest reliability of the UFOV. Six participated in the development of a training protocol and in a 20-session visual attention retraining program. RESULTS: UFOV scores indicated substantial reduction in visual attention in clients after stroke, with older participants performing the most poorly. Test-retest reliability was moderate (ICC = .70). Mean UFOV scores improved significantly after retraining. CONCLUSION: Although UFOV scores indicated poor visual attention skills in clients with stroke, preliminary information suggests that UFOV scores significantly improve with training.

Near fatal acute colchicine intoxication in a child. A case report.

UNLABELLED: An 8-year-old child with familial Mediterranean fever exhibited signs of colchicine intoxication while receiving prophylactic doses of the drug. She developed gastrointestinal, central nervous system, cardiovascular and haematological disturbances. Over 2 months she had been drinking high doses of natural grapefruit juice which, combined with long-term colchicine therapy and a viral upper respiratory tract infection, increased her susceptibility to the drug. CONCLUSION: To the best of our knowledge, this is the first time colchicine intoxication in this age group has been described in the English literature.

Outcome of "out of hospital" cardiopulmonary arrest in children admitted to the emergency room.

BACKGROUND: The outcome of cardiopulmonary arrest in children is poor, with many survivors suffering from severe neurological defects. There are few data on the survival rate following cardiopulmonary arrest in children who arrived at the emergency room without a palpable pulse. OBJECTIVE: To determine the survival rate and epidemiology of cardiopulmonary arrest in children who arrived without a palpable pulse at a pediatric ER in southern Israel. METHODS: We retrospectively reviewed the medical records of all patients with cardiopulmonary arrest who arrived at the ER of the Soroka University Medical Center during the period January 1995 to June 1997. RESULTS: The study group included 35 patients. Resuscitation efforts were attempted on 20, but the remaining 15 showed signs of death and were not resuscitated. None of the patients survived, although one patient survived the resuscitation but succumbed a few hours later. The statistics show that more cardiopulmonary arrests occurred among Bedouins than among Jews (32 vs. 3, P < 0.0001). CONCLUSIONS: The probability of survival from cardiopulmonary arrest in children who arrive at the emergency room without palpable pulse is extremely low. Bedouin children have a much higher risk of suffering from out-of-hospital cardiopulmonary arrest than Jewish children.

Effect of ligation of spleen vessels on left ventricular function and coronary blood flow in dogs injected with scorpion venom.

Scorpion sting may cause myocardial dysfunction in human victims, probably by increased O2 demand and decreased O2 supply. In dog, scorpion venom (SV) causes no myocardial dysfunction. Myocardium is probably protected by "autotransfusion" of blood from the spleen to the circulation, increasing coronary blood flow (CBF) and O2 delivery. We hypothesized that ligation of spleen vessels prior to injection of SV in dogs would prevent the autotransfusion of blood, thereby causing myocardial ischemia due to decreased CBF, simulating the hemodynamic pattern of human envenomation. We studied cardiac output (CO), CBF, left ventricular (LV) O2 delivery and contractility in 11 dogs injected with 0.07 mg/kg of SV (Leiurus quinquestriatus). Ligation of spleen vessels was performed on 6 of the 11 dogs prior to SV injection. 15 min after SV injection CO had increased by 186% in control dogs, while ligation of spleen vessels completely prevented CO elevation (p<0.001). In both groups, however, LV dp/dt increased by 400% and dp/dt/p by 170% (p<0.001). CBF increased by 350% and 550% in the spleen and control groups (p<0.001) respectively. This was associated with elevation of diastolic blood pressure and a decrease in coronary vascular resistance. LV O2 delivery increased (p<0.05) in both groups. At 60 minutes there was a decrease in CO, stroke work, and LV end systolic pressure in both groups, while LV contractility remained above baseline. Scorpion venom injection in dogs causes an initial increase in CO by auto-transfusion of blood from the spleen. Prevention of the autotransfusion does not preclude increases in CBF, O2 delivery and LV contractility.

Visual testing for readiness to drive after stroke: a multicenter study.

OBJECTIVE: The purpose of this study was to determine the ability of a visual-perception assessment tool, the Motor-Free Visual Perception Test, to predict on-road driving outcome in subjects with stroke. DESIGN: This was a retrospective study of 269 individuals with stroke who completed visual-perception testing and an on-road driving evaluation. Driving evaluators from six evaluation sites in Canada and the United States participated. Visual-perception was assessed using the Motor-Free Visual Perception Test. Scores range from 0 to 36, with a higher score indicating better visual perception. A structured on-road driving evaluation was performed to determine fitness to drive. Based on driving behaviors, a pass or fail outcome was determined by the examiner. RESULTS: The results indicated that, using a score on the Motor-Free Visual Perception Test of < or =30 to indicate poor visual-perception and >30 to indicate good visual perception, the positive predictive value of the Motor-Free Visual Perception Test in identifying those who would fail the on-road test was 60.9% (n = 67/110). The corresponding negative predictive value was 64.2% (n = 102/159). Univariate logistic regression analyses revealed that older age, low Motor-Free Visual Perception Test scores and a right hemisphere lesion contributed significantly to identifying those who failed the on-road test. CONCLUSIONS: The predictive validity of the Motor-Free Visual Perception Test is not sufficiently high to warrant its use as the sole screening tool in identifying those who are unfit to undergo an on-road evaluation.

Disseminated intravascular coagulation after cerastes vipera envenomation in a 3-year-old child: a case report.

This study presents a case of severe disseminated intravascular coagulation (DIC) in a 3-year-old child following envenomation by the snake, Cerastes vipera. A literature search revealed very few similar cases. We describe a child who was bitten in his left foot by a snake identified as a C. vipera. Initial symptoms were relatively benign. Local signs included a hemorrhagic vesicle at the site of the bite with marked swelling of the entire leg. Twenty-four hours later, the child developed severe bleeding due to DIC, which lasted 5 days and required repeated administration of blood and blood products and total exchange transfusion. The patient was discharged from the hospital after 7 days in good condition. To the best of our knowledge, severe DIC following envenomation by a C. vipera has not been previously described in the literature. Treatment was essentially supportive. The case report indicates that a specific antivenin against this snake's venom should be made available in our area.

Signs and symptoms of carbamazepine overdose in young children.

OBJECTIVE: To examine common signs and symptoms of mild to moderate carbamazepine (CBZ) overdose in young children. METHODS: The medical records of previously healthy children admitted to the pediatric departments for acute accidental CBZ poisoning during the years 1993-1998 were evaluated retrospectively. Information was retrieved on serum CBZ levels, signs and symptoms on admission and during hospitalization, ECG findings, and chemical laboratory test. RESULTS: There were 14 exposed children all under the age of 5 years. These children accidentally took CBZ prescribed for a family member. The diagnosis of CBZ poisoning in seven children was unknown on admission because of inadequate history and was revealed only on toxicology screen. Nystagmus and drowsiness occurred in 8 of the 14 children, nystagmus and ataxia in 4 children, and drowsiness and tachycardia in another 2 children. The peak CBZ serum levels in these children ranged from 18 microg/ml to 32 microg/ml, mean + SD; 25 microg/ml + 4.64 microg/ml (therapeutic range: 5-10 microg/ml). CONCLUSION: Based on a certain group of young pediatric patients with mild to moderate CBZ poisoning, it is concluded that, nystagmus is the most common sign of this overdose. Other common signs are drowsiness and ataxia. The presence of nystagmus and CNS depression of unknown etiology, in a young child should suggest the possibility of CBZ toxicity.

Severe infantile hypothermia: short- and long-term outcome.

OBJECTIVE: To determine short- and long-term outcomes of infants with severe hypothermia (< or = 28 degrees C) treated in a pediatric intensive care unit (PICU). DESIGN: (1) Retrospective evaluation of medical records of all patients admitted for severe infantile hypothermia from 1984 to 1993. (2) Medical and developmental evaluations of survivors of severe infantile hypothermia 3-12 years after hospital discharge. SETTING: Six-bed PICU of a university teaching hospital. PATIENTS: Eighteen infants who arrived at the emergency room with a rectal temperature between 20 and 28 degrees C. MEASUREMENTS AND RESULTS: The ages of patients ranged between 5 and 30 days. Fifteen were Bedouins and three were Jews. Clinical features included sepsis in 9 (septic shock in 5 of 9) patients, respiratory failure in 11 and overt bleeding in 5. Rewarming was applied using rapid external warming under a radiant heater. Five infants died shortly after arrival and one patient at age 6 years; all of them had sepsis on arrival. Of the 12 survivors examined at ages 3-12 years, ten had normal psychomotor achievements, while the remaining two had mild (1 patient) and severe (1 patient) psychomotor retardation. Both of the latter two had sepsis on first admission for hypothermia. All nine hypothermic infants, who had no sepsis, had normal medical examinations and normal developmental achievements for their ages. CONCLUSION: Severe infantile hypothermia is a serious condition. When treating patients in a modern PICU, morbidity and mortality are mainly related to the presence or absence of an associated septicemia. Infants without septicemia may have normal growth and development.

Repeat computed tomographic scan within 24-48 hours of admission in children with moderate and severe head trauma.

OBJECTIVE: To asses the yield and contribution of a routine predetermined repeat head computed tomographic (CT) scan within 24-36 hrs in pediatric patients with moderate to severe head trauma. DESIGN: Records review. SETTING: Five pediatric intensive care units. PATIENTS: We reviewed the charts of 173 consecutive pediatric patients with moderate to severe head trauma (Glasgow Coma Scale score of < or = 11) that survived the first 24 hrs after being admitted to five Israeli trauma centers. Clinical data collected included status at admission, at the time between the first and second CT scans, and after the second scan. Head details of the first, second, and, if performed, third CT scan were collected. Treatment strategy during each period was recorded, including any change in treatment after each CT scan. MEASUREMENTS AND MAIN RESULTS: A total of 47 (27%) of the second CT scans showed new lesions including six intracranial hemorrhages, 17 cases of worsening brain edema, and 18 newly diagnosed brain contusions. However, none of these findings necessitated surgical intervention or any change in therapy. Of the 67 patients who underwent a third CT scan, two cases required surgical intervention because of new findings in the third CT. CONCLUSIONS: A second routine prescheduled head CT scan within 24-36 hrs after admission in pediatric patients with moderate to severe head trauma is unlikely to yield any change in therapy. Clinically and intracranial pressure-oriented CT scan may better select and diagnose patients who require changes in therapy, including surgery. Studies aimed to determine the ideal timing for the second are warranted.

Airway obstruction by Ascaris, roundworm in a burned child.

Ascaris lumbricoides, roundworm, is a Nematode parasite infecting about 1 billion people worldwide. We report the case of a ten-year-old Bedouin girl hospitalized with burns to 45% of her body surface area, including the face. The patient was intubated upon admission and mechanically ventilated. Four days later she was extubated but required reintubation 15 min later for severe hypoxemia. Laryngoscopy disclosed an unidentified tube which obstructed the opening of the larynx. The 'tube' was removed by Magill forceps. The object was identified as a 35 cm long Ascaris roundworm. Once the worm was removed the patients' respiratory condition dramatically improved. We review the main features of Ascaris infection and some similar cases of airway obstruction caused by this worm.

Carbamate and organophosphate poisoning in young children.

OBJECTIVE: Retrospective evaluation of the clinical course of carbamate and organophosphate poisoning in young children. DESIGN: The records of 36 children intoxicated with carbamate and 16 children intoxicated with organophosphate (age range: 2 to 8 years, median: 2.8 years) were examined retrospectively. The carbamate agents were identified as methomyl or aldicarb, and the organophosphate as parathion, fenthion, malathion, and diazinon. The causes of poisoning were accidental ingestion in 46 children and inhalation in six children. CLINICAL SETTING: Pediatric Intensive Care Unit of a teaching hospital. INTERVENTIONS: Gastric lavage was performed, and activated charcoal was administered to all children who had ingested poisonous pesticides. Atropine sulphate was administered intravenously in repeated doses to all children with bradycardia, diarrhea, salivation, and miosis. Obidoxime chloride was administered to patients with organophosphate poisoning and to those in whom the ingested material was unidentified on admission. RESULTS: Predominant symptoms were related to central nervous system depression and severe hypotonia. Other clinical signs such as miosis, diarrhea, salivation, bradycardia, and fasciculation were less frequent, while tearing and diaphoresis were not observed. Pulmonary edema developed in six patients with organophosphte poisoning. Three children required mechanical ventilation for several hours. One child (organophosphate poisoning) died shortly after arrival at the emergency department. All other children recovered completely. CONCLUSION: Based on a relatively large group of young pediatric patients with carbamate and organophosphate poisoning, it is concluded that the clinical presentation differed from those described in adults. Absence of classic muscarinic effects does not exclude the possibility of cholinesterase inhibitor agents poisoning in young children with central nervous system depression.

Effects of adrenergic-receptor blockade and ligation of spleen vessels on the hemodynamics of dogs injected with scorpion venom.

OBJECTIVE: In dogs, scorpion venom evokes a rapid increase in cardiac output (CO) that decreases below baseline level in 1 hr. The changes in CO have recently been shown to be related to the effect of the venom on venous return. In the present study, we tested the hypothesis that changes in determinants of venous return are secondary to sympathoadrenal stimulation evoked by the venom, which causes splenic contracture in the first stage of envenomation leading to increased mean circulatory pressure (MCP) and CO. Persistence of adrenergic response is the main factor leading to the second stage of envenomation, characterized by an increase in resistance to venous return (Rv) and a decrease in CO. DESIGN: Repeated measures, prospective study in dogs. SETTING: University-affiliated research laboratory. SUBJECTS: Mixed-breed dogs injected with scorpion venom. INTERVENTIONS: The effects of alpha- and beta-adrenergic-receptor blockade (blockade group, n = 9 dogs) and effects of ligation of spleen vessels (spleen ligation group, n = 11 dogs) following intravenous injection of scorpion venom from Leiurus quinquestriatus (0.05 mg/kg) were tested on the determinants of venous return and compared with the effects of scorpion venom alone (control group, n = 6 dogs). MEASUREMENTS AND MAIN RESULTS: Scorpion venom in the control group caused a marked increase in CO from 2.9+/-0.2 SD L/min to 6.5+/-2.2 L/min (p<.001) and MCP from 8.7+/-2.7 torr (1.2+/-0.35 kPa) to 21.6+/-1.4 torr (2.9+/-0.19 kPa) (p<.001) within 5 mins after venom injection. Cardiac output and MCP markedly decreased at 60 mins to 1.8+/-0.3 L/min (p<.001) and 7.3+/-3.8 torr (1.0+/-0.5 kPa) (p<.05), respectively. Rv did not change at 5 mins but increased from 196+/-50 dyne x sec/cm5 to 335+/-102 dyne x sec/cm5 (p<.01) at 60 mins. Adrenergic-receptor blockade attenuated the increase of CO and MCP at 5 mins, from 2.1+/-0.5 L/min to 2.7+/-1 L/min (p<.001) and from 5.6+/-2.0 torr (0.8+/-0.27 kPa) to 7.5+/-2.3 torr (1.0+/-0.31 kPa) (p<.05), respectively. By 60 mins, both CO and MCP returned to baseline, while Rv was not affected and was maintained at 204+/-158 dyne x sec/cm5. Ligation of spleen vessels prevented a CO increase at 5 mins and it was maintained at baseline value (2.5+/-0.6 L/min). However, MCP increased from 7.9+/-0.5 torr to 12+/-1.3 torr (p<.05). At 60 mins, CO decreased to 1.6+/-0.7 L/min (p<.01) while MCP returned to baseline. The changes in MCP were accompanied by significant increases of Rv from 152+/-24 dyne x sec/cm5 to 383+/-93 dyne x sec/cm5 (p<.001) at 5 mins, and 510+/-175 dyne x sec/cm5 (p<.01) at 60 mins. CONCLUSIONS: The changes in CO and MCP following scorpion venom injection in dogs are in part related to sympathetic stimulation. Adrenergic-receptor blockade attenuated the initial inotropic effect of the venom and completely prevented a late decrease in CO and MCP. The increase in Rv is the most important factor for late decrease in CO, and results from persistent adrenergic-receptor stimulation. In addition, an Rv increase apparently expresses vasoconstriction and redistribution of blood flow. The initial increase in CO and MCP is explained mainly by adrenergic-receptor effects on the spleen leading to augmented circulatory blood volume.