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Left Hand (leave + hand)
Selected AbstractsMaurice Ravel and right-hemisphere musical creativity: influence of disease on his last musical works?EUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2002L. Amaducci The problem of finding correspondence between a particular neuronal organization and a specific function of the human brain remains a central question of neuroscience. It is sometimes thought that language and music are two sides of the same intellectual coin, but research on brain-damaged patients has shown that the loss of verbal functions (aphasia) is not necessarily accompanied by a loss of musical abilities (amusia). Amusia without aphasia has also been described. This double dissociation indicates functional autonomy in these mental processes. Yet verbal and musical impairments often occur together. The global picture that emerges from studies of music and its neural substrate is by no means clear and much depends on which subjects and which aspect of musical abilities are investigated. An illustration of these concepts is provided by the case of the French composer Maurice Ravel, who suffered from a progressive cerebral disease of uncertain aetiology, with prominent involvement of the left hemisphere. As a result, Ravel experienced aphasia and apraxia and became unable to compose. The available facts favour a clinical diagnosis of primary progressive aphasia (PPA), with the possibility of an overlap with corticobasal degeneration (CBD). In view of Ravel's clinical history, we propose that two of his final compositions, the Bolero and the Concerto for the Left Hand, include certain patterns characteristic of right-hemisphere musical abilities and may show the influence of disease on the creative process. [source] Egocentric mental rotation in Hungarian dyslexic childrenDYSLEXIA, Issue 1 2001Kázmér Karádi Abstract A mental rotation task was given to 27 dyslexic children (mean age 9 years, 2 months) and to 28 non-dyslexic children (mean age 8 years, 8 months). Pictures of right and left hands were shown at angles of 0, 50, 90 and 180 degrees, and the subjects were required to indicate whether what was shown was a right hand or a left hand. It was found that, in this task, the dyslexics did not show the normal pattern of response times at different angles, and also, that they made more errors than the controls. It is argued that this result is compatible with hypothesis that, in typical cases of dyslexia, there is a malfunctioning in the posterior parietal area. Copyright © 2001 John Wiley & Sons, Ltd. [source] Basal ganglia and frontal involvement in self-generated and externally-triggered finger movements in the dominant and non-dominant handEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2009Félix-Etienne François-Brosseau Abstract Although there are a number of functional neuroimaging studies that have investigated self-initiated and externally-triggered movements, data directly comparing right and left hands in this context are very scarce. The goal of this study was to further understand the role of the basal ganglia and prefrontal cortex in the realm of self-initiated and externally-triggered right and left hand movements. Young healthy right-handed adults performed random, follow and repeat conditions of a finger moving task with their right and left hands, while being scanned with functional magnetic resonance imaging. Significant activation of the dorsolateral prefrontal cortex was observed when comparing the self-initiated movements with the repeated control and externally-triggered movements when using either hand in agreement with its role in monitoring. The caudate nucleus activation was found during self-initiated conditions compared with the control condition when either hand was used, showing that it is particularly involved when a new movement needs to be planned. Significant putamen activation was observed in all within-hand contrasts except for the externally-triggered vs. control condition when using the left hand. Furthermore, greater putaminal activation was found for the left vs. the right hand during the control condition, but for the right vs. the left hand subtraction for the self-initiated condition. Our results show that the putamen is particularly involved in the execution of non-routine movements, especially if those are self-initiated. Furthermore, we propose that, for right-handed people performing fine movements, as far as putamen involvement is concerned, the lack of proficiency of the non-dominant hand may prevail over other task demands. [source] Rapid cortical reorganisation and improved sensitivity of the hand following cutaneous anaesthesia of the forearmEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2009Anders Björkman Abstract The cortical representation of various body parts constantly changes based on the pattern of afferent nerve impulses. As peripheral nerve injury results in a cortical and subcortical reorganisation this has been suggested as one explanation for the poor clinical outcome seen after peripheral nerve repair in humans. Cutaneous anaesthesia of the forearm in healthy subjects and in patients with nerve injuries results in rapid improvement of hand sensitivity. The mechanism behind the improvement is probably based on a rapid cortical and subcortical reorganisation. The aim of this work was to study cortical changes following temporary cutaneous forearm anaesthesia. Ten healthy volunteers participated in the study. Twenty grams of a local anaesthetic cream (EMLA®) was applied to the volar aspect of the right forearm. Functional magnetic resonance imaging was performed during sensory stimulation of all fingers of the right hand before and during cutaneous forearm anaesthesia. Sensitivity was also clinically assessed before and during forearm anaesthesia. A group analysis of functional magnetic resonance image data showed that, during anaesthesia, the hand area in the contralateral primary somatosensory cortex expanded cranially over the anaesthetised forearm area. Clinically right hand sensitivity in the volunteers improved during forearm anaesthesia. No significant changes were seen in the left hand. The clinically improved hand sensitivity following forearm anaesthesia is probably based on a rapid expansion of the hand area in the primary somatosensory cortex which presumably results in more nerve cells being made available for the hand in the primary somatosensory cortex. [source] Difficult laparoscopic cholecystectomy in acute cholecystitis: use of ,finger port', a new approachHPB, Issue 3 2003R Sinha Background Adhesions in acute cholecystitis tax even the more experienced operator during laparoscopic cholecystectomy. Blunt and sharp dissection, electrocautery, laser, hydrodissection, and ultrasonic dissection may all have their limitations. Thus there is a need for an alternative and more effective method. Method Laparoscopic cholecystectomy was carried out in 281 patients with acute cholecystitis. Separation of the gallbladder from the adherent structures was carried out in 13 patients, using the forefinger of the left hand introduced through the right hypochondrial port. In two patients a second finger was introduced through the epigastric port. Results The mean time required for the dissection was 7.9 minutes. Finger dissection failed in three patients because of dense adhesions on a high subcostal position of the gallbladder. Discussion Finger dissection is easy, fast, and limits injury because of the direct vision and tactile sensation, which are missing in other methods of laparoscopic dissection. [source] Osteobiography of a high-status burial from the lower Río Verde Valley of Oaxaca, MexicoINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 6 2008A. T. Mayes Abstract This paper presents the osteobiography of an individual from an early complex society who was clearly of "special" social status but was not classified a ruling elite. Our case derives from a unique burial found at the small site of Yugüe, located in the lower Río Verde valley on the Pacific coast of Oaxaca, Mexico. Burial 14-Individual 16 (B14-I16) dates to the late Terminal Formative Period (CE 100,250), an era of regional political centralization and concomitant social inequality. B14-I16 was interred with several valuable grave offerings. A plaster-backed pyrite mirror was found below his mandible, and his left hand held an elaborately incised flute made from a deer femur. The flute is the only object of its kind known for all of Terminal Formative Mesoamerica. Drawing on the physicality of inequality, we employ osteobiography to assess the social hierarchy. Although B14-I16 was clearly an individual of unusual status in the context of Yugüe, he was not immune from the biological assaults that affected people of less distinguished social position at this time. Like his contemporaries of all social statuses, he suffered ill health in the years during which he was weaned. However, a longer weaning period and access to additional resources may have positioned him to endure later illness better than others in this population. Passing the critical transition period at age 6 ½, a time when many children died in this burial site, his adolescent health was better than that of others in this population. Although B14-I16 did have adult responsibilities, he didn't engage in the kinds of physical labour that marked the skeletons of others. The placement of Burial B14-I16 in the middle tiers of the lower Río Verde valley's ancient social hierarchy provides insight into issues of inequality and status on an individual scale. Copyright © 2008 John Wiley & Sons, Ltd. [source] Symplastic glomus tumor , a rare but distinct benign histological variant with analogy to other ,ancient' benign skin neoplasmsJOURNAL OF CUTANEOUS PATHOLOGY, Issue 10 2009Jivko Kamarashev A 78-year-old woman presented with a nail deformity of the index finger of the left hand associated with paroxysmal pain upon cold exposure. Histologically, a well-circumscribed tumor of 3 mm diameter was found in the dermis. The neoplastic cells in some areas were of pronouncedly variable size and cytomorphology, mostly epithelioid in shape, with eosinophilic cytoplasm and indistinctly defined cell borders. Pronounced nuclear pleomorphism and atypia were striking features, but no mitotic figures were noted. Multinuclear cells were present as were numerous small-to-medium vessels throughout the tumor. The tumor stroma showed myxoid areas. Immunohistochemistry showed cytoplasmic and membranous expression of smooth muscle actin and vimentin. The histological features and immunoprofile were consistent with the diagnosis of symplastic glomus tumor, a rare histological variant, which has been defined as a glomus tumor exhibiting marked nuclear atypia, in the absence of any other criteria for malignancy. The biological behavior of the tumor is benign. It is essential to differentiate this entity from malignant glomus tumor, which has metastatic potential. Even prominent cellular atypia and nuclear pleomorphism in a glomus tumor as in our case is not a marker of malignancy in the absence of additional criteria. [source] Basal cell carcinoma with matrical differentiation in a transplant patient: A case report and review of the literatureJOURNAL OF CUTANEOUS PATHOLOGY, Issue 6 2005Faizi Ali Background:, Shadow cells, characterized by basaloid squamous cells with a distinct well-defined border and a central unstained area as a shadow of lost nuclei, are characteristic of pilomatricoma, a distinct neoplasm of hair matrix differentiation. The presence of shadow cells within tumor islands composed of follicular germinative cells of an otherwise classic basal cell carcinoma (BCC) has been considered as a distinct diagnostic category of BCC with matrical differentiation. We present a case of BCC with matrical differentiation in a transplant patient. To our knowledge, only 10 cases [Aloi et al. Am J Dermatopathol 1988; 10: 509; Ambrojo et al. Am J Dermatopathol 1992; 14: 293; Sagol et al. East J Med 1999; 4: 37; Kwittken J. Cutis 2002; 69: 57; Kim et al. Yonsei Med J 2003; 44: 523] of BCC showing matrical differentiation have been reported. None have been reported arising on the background of immunosuppression. Methods:, A 58-year-old male cardiac transplant patient with a nodule on the dorsum of left hand was studied. It arose and enlarged rapidly within a few months, causing irritation and bleeding. The nodule was surgically excised and submitted for histopathologic evaluation. The sections were prepared by hematoxylin and eosin (H&E) method. Results:, The H&E-stained sections of the hand lesion revealed multiple nodular masses of basaloid follicular germinative cells. In some areas, there was peripheral palisading and stromal retraction artifact typical of classic BCC. In these areas, the tumor nodules were connected to the epidermis, whereas in others, it extended deep into the reticular dermis to the subcutaneous fat junction. Elsewhere, the majority of the tumor contained a population of shadow cells, similar to those in pilomatricoma, with basaloid-appearing matrical cells in the periphery. Trichohyaline granules were identified in the cytoplasm of many of the peripheral basaloid cells. These granules are one of the characteristic features of follicular matrix differentiation. Mitoses were rare. Areas of cystic degeneration were present throughout the tumor. There was no evidence of an infiltrating growth pattern, lymphovascular invasion, or sarcomatoid growth pattern. Conclusion:, BCC with matrical differentiation is a distinct pathologic entity and a rare subtype of BCC featuring shadow and matrical cells, typically seen in pilomatricoma, a benign hair matrix neoplasm. This tumor has not yet been reported in an immunosuppressed transplant patient. [source] Practice and endpoint accuracy with the left and right hands of old adults: The right-hemisphere aging modelMUSCLE AND NERVE, Issue 3 2008Brach Poston PhD Abstract The purpose of the study was to quantify the aging-related differences in endpoint accuracy during isometric contractions of the left and right hands based on the prediction that declines in motor performance with aging may be greater for muscles controlled by the right hemisphere. Twelve young (6 men, 25 ± 5 years) and 12 old (6 men, 76 ± 6 years) adults performed a task that involved matching the peak of a force,time trajectory to a target. The old adults were less accurate than the young men and exhibited greater endpoint error with the left hand than the right hand on day 1, but not on days 2 and 3. Although electromyographic amplitude was similar between hands, old adults exhibited greater timing variability. These findings indicate that given sufficient practice there was no difference in endpoint accuracy between the left and right hands of old adults, which is not consistent with the prediction of an asymmetrical decline in motor performance by the right-hemisphere aging model. Conversely, an inability by an old adult to achieve similar accuracy with both hands during such tasks likely indicates an underlying motor impairment. Muscle Nerve, 2007 [source] Linear Morphea Presenting as Acquired Unilateral EdemaPEDIATRIC DERMATOLOGY, Issue 2 2007Katherine H. Fiala M.D. In addition, linear hypopigmented patches were noted along the left forearm and leg, with no appreciable scarring or induration. The edema on the left-hand side of his body progressed so that he developed tense bullae on his left hand. Two months later, the hypopigmented patches were indurated and bound-down, especially over the left groin and thigh. A biopsy specimen from this area showed features characteristic of morphea. In this patient, dilated lymphatic channels secondary to the sclerosis of the morphea caused the bullae. Bullous morphea is a rare condition. We were unable to find any reports its occurrence in children under 18 with associated lymphedema. This entity should be included in the differential for acquired unilateral edema in children. [source] Tuberous Sclerosis with MacrodactylyPEDIATRIC DERMATOLOGY, Issue 6 2000Bijaylaxmi Sahoo M.D. We report a 15-year-old girl with a thick, loose hyperpigmented area on the dorsum of the left hand with macrodactyly. A skin biopsy specimen from the dorsum of the left hand revealed dense collagenization in the dermis. Radiographs showed marked irregular thickening of the cortex of the metacarpals and phalanges of the left index and middle fingers. [source] Does second-to-fourth digit length ratio (2D:4D) predict age at menarche in women?AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2010Samuli Helle Prenatal steroid levels, estimated as the ratio of second-to-fourth digit length (2D:4D), have been related to reproductive success in women, but direct associations between 2D:4D and physiological measures of fertility remain rare. A recent study reported that lower, masculinized right hand 2D:4D was correlated with delayed age at menarche in women. We addressed this question by investigating whether 2D:4D was associated with recalled age at menarche in 282 post-reproductive Finnish women, using Cox regression model that controlled for a woman's sibling composition, urban or rural residence and temporal trend in menarcheal age. We found no evidence that neither the 2D:4D of the right nor the left hand were related to a woman's age at menarche among these Finnish women. Am. J. Hum. Biol., 2010. © 2009 Wiley-Liss, Inc. [source] Prenatal diagnosis of jumping translocation involving chromosome 22 with ultrasonographic findingsPRENATAL DIAGNOSIS, Issue 11 2005Halil Aslan Abstract We report on the prenatal diagnosis and ultrasonographic findings of a second-trimester fetus with jumping translocation involving chromosome 22. A 28-year-old gravida 2, partus 1, Turkish woman was referred for genetic counselling and ultrasonographic examination at 18 weeks' gestation because of a high risk of trisomy 21 in triple test. Prenatal ultrasonography showed tetralogy of Fallot with a diverticular dilatation of the pulmonary artery, flattened brow, complete absence of the right upper limb, hypospadias, oligodactyly (three digits) in left hand and in both feet, and hyperechogenic abdominal foci. Amniocentesis revealed a karyotype of 46,XY[4]/46,XY,,8,+ der(8),t(8;22)(q24.3;q11.21)[2]/45, XY,,22,,8,+ der(8)t(8;22)(q24.3;q11.21)[22]/45,XY,,22,,5,+ der(5)t(5;22)(q35.3;q11.21)[44]. A C-banding and FISH study with a specific centromeric probe (D14Z1/D22Z1) for chromosome 22 was made. In our case, partial monosomy for the regions 22q11.21,22pter, 8q24.3,8qter and 5q35.3,5qter may partially explain the fetal malformations. Copyright © 2005 John Wiley & Sons, Ltd. [source] Laterality in semi-free-ranging black and white ruffed lemurs (Varecia variegata variegata): head-tilt correlates with hand use during feedingAMERICAN JOURNAL OF PRIMATOLOGY, Issue 12 2009Eliza L. Nelson Abstract Previous studies in human and chimpanzee infants have identified a predictive relationship between early rightward head orientation and later right hand use. Data from lemurs suggest a leftward bias in hand preference, but there are no data on head positioning. The purpose of this study was to examine the relationship between head and hand preferences in the black and white ruffed lemur (Varecia variegata variegata). Ruffed lemurs rotate the head vertically during chewing in a behavior called head-tilting. Frequency of head-tilting and bouts of unimanual hand use were measured during normal feeding in a semi-free-ranging population of lemurs. Subjects were provisioned at feeding platforms twice daily with fresh fruits, vegetables, and other food items. Sampling was spontaneous and all observations were videotaped. No group-level bias was found for head-tilting, but a left hand bias emerged for hand use. A positive relationship was found between direction of head-tilting preference and direction of hand use preference such that left head-tilts increased as left hand use increased. Furthermore, left head-tilts increased as the degree of hand preference lateralization increased. When the hand used to bring food to the mouth just before head-tilting was examined, there was a strong bias for the left hand to precede left head-tilts. For right head-tilts, however, lemurs were equally likely to use either hand before head-tilting. Overall a strong relationship was found between the left hand and left head-tilting in black and white ruffed lemurs, suggesting a common link between these behaviors. However, the direction of bias was different from that seen in human and chimpanzee studies. Additional studies on patterns of laterality would be informative for understanding how laterality has changed across the primate order and the adaptive significance of laterality in primates. Am. J. Primatol. 71:1032,1040, 2009. © 2009 Wiley-Liss, Inc. [source] Effect and persistency of botulinum toxin iontophoresis in the treatment of palmar hyperhidrosisAUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 2 2008Sanaz Davarian SUMMARY The purpose of this study was to investigate the efficacy and persistence of the hypohidrosis induced by iontophoresis of botulinum toxin type A in patients with palmar hyperhidrosis. Eight patients with severe palmar hyperhidrosis participated in this study. Iontophoresis of botulinum toxin was applied to the patients' dominant (right) hand and the other hand was the control treated with normal saline. Gravimetry and iodine,starch tests were performed to evaluate the rate of sweating. The evaluation sessions were at baseline, 2 and 4 days, 1, 2, 3, 4, 8 and 12 weeks after treatment. The patients were also asked to fill out the Dermatology Life Quality Index questionnaire at 2, 4, 8 and 12 weeks after treatment. The mean sweating rate significantly reduced at the first, second, third and fourth week and the second and third month (P < 0.05) after the treatment in the right hand, and the third and fourth week (P < 0.05) after treatment in the left hand. Iontophoresis of botulinum toxin rapidly induced a quick reduction of sweating rate for at least 3 months with no pain, muscle weakness or other side-effects. [source] Fabry disease in a heterozygote presenting as hand ischaemia and painful acroparaesthesiaAUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 1 2007Linda Martin SUMMARY A 48-year-old woman presented with acute unilateral ischaemia of the left hand. She had a background of chronic peripheral neuropathic pain, palpitations, anaemia and an episode of superficial thrombophlebitis. Physical examination revealed non-blanching purple discoloration of her left fingers and her left thumb, index finger and thenar eminance appeared ischaemic. Digital subtraction angiography of the left hand demonstrated reduced flow. Skin punch biopsy histology was unremarkable. The diagnosis of Fabry disease was made on urine lipid profile analysis and confirmed by reduced peripheral blood leukocyte ,-galactosidase A activity. [source] Sweating impairment in patients with multiple sclerosisACTA NEUROLOGICA SCANDINAVICA, Issue 5 2009A. Saari Objectives,,, To measure sweating in patients with multiple sclerosis (MS). Materials,and methods ,, Sweating was measured by an evaporimeter after a heating stimulus in 29 MS patients and in 15 healthy control subjects. Results,,, The MS patients sweated markedly less than the controls. After 10 min of heating the sweating was significantly lower in the forehead (P = 0.034), feet (right, P = 0.033; left, P = 0.037) and legs (right, P = 0.043; left, P = 0.029) of the MS patients than in those of the controls. After 15 min of heating the difference was statistically significant only in the feet (right, P = 0.043; left, P = 0.029). The Expanded Disability Status Scale score correlated inversely with sweating at 15 min of heating in the left hand (r = 0.42, P < 0.05), and in the left (r = 0.36, P < 0.05) and right foot (r = 0.37, P < 0.05). Conclusions,,, MS is associated with an impairment in thermoregulatory sweating which seems to be related to the disease severity. [source] Abnormal peripheral vascular response to occlusion provocation in normal tension glaucoma patientsACTA OPHTHALMOLOGICA, Issue 2007J WIERZBOWSKA Purpose: To assess peripheral vascular reactive hyperemia in response to occlusion provocation test, using two-channels laser Doppler probe in patients with normal tension glaucoma (NTG) and normal subjects. Methods: 15 patients with NTG (12 women and 4 men), mean aged 58,9 and 15 control subjects (13 women and 2 men), mean aged 60,6 were subjected to an occlusion test. The experiment comprised following steps: 1/ a 5-minute baseline-period 2/ a 2-minute occlusion of the left hand using a 15 cm wide cuff located directly over the elbow (the pressure in the cuff was 50 mmHg higher than the systolic pressure measured on the arm 3/ a 15- minute final recovery period after occlusion. Finger hyperemia was assessed by two-channels laser-Doppler flowmeter MBF-3d, Moor Instruments, Ltd., continuously during the experiment. For measurements of hyperemia two surface probes were attached to the pulp of the second finger (mean probe) and third finger (basic probe) of the left hand. The following hyperemia parameters were measured: RF (rest flow), BZ (biological zero), TM (time to peak flow), TH (half-time of hyperemia), MAX (maximum of hyperemia) and hyperemia amplitude (MAX-RF)/RF 100% was calculated. Kruskal-Wallis test analysis was used to test the differences between the group of patients and normal subjects for TM1,MXF1 (basic probe) and TM2, MXF2 (mean probe) parameters. Results: In NTG patients, TM1 was significantly higher comparing with healthy subjects whereas MAX was significantly lower as compared to the control group. Conclusions: Occlusion provocation test elicits a different systemic hyperemia response in patients with NTG compared with healthy subjects. [source] Periungual lesions in pyoderma gangrenosumCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 5 2009A. Reich Summary Pyoderma gangrenosum (PG) is a progressive cutaneous necrosis of unknown origin. We report a case of PG presenting with periungual lesions. A 57-year-old woman was on treatment with ciclosporin A for PG. During tapering of the ciclosporin A dose, proliferating periungual lesions developed on the third and fourth finger of the left hand, the fourth finger of the right hand, and on the right great toe and the left fifth toe. All lesions appeared within a 4-week period. These abnormalities were ulcerated, involved about one-third of the distal part of the lateral nail folds including the part of nail fold bordering on the free edge of the nails, and were very painful. The skin biopsy was consistent with that seen in PG. Increasing the ciclosporin A dose led to significant improvement in the periungual lesions within the next few weeks and complete resolution within 6 months. [source] Quantitative effect of anodal current in the treatment of primary hyperhidrosis by direct electrical currentINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 7 2006rul H. Aydemir MD Aim, To determine the quantitative effect and technique of use of the anodal current for the treatment of palmoplantar hyperhidrosis on local areas of the palms and soles. Methods, Twelve patients (four males and eight females) with idiopathic palmoplantar hyperhidrosis were enrolled in this study. Having determined the initial sweat intensities of both hands using the pad glove method, direct electrical current (d.c.) treatment was applied to the palms of the patients using a complete regulated d.c. unit for which the current and potential ranges were 0,30 mA and 0,90 V, respectively. Electrodes were placed into two separate water plates, and covered with pad made from gauze and cotton material. The pads were moisturized with tap water for current conduction. The anodal current was applied to the right hands of six patients (group I) and to the left hands of the remainder (group II). After seven treatments had been completed for the palms, the final sweat intensities of the hands were measured. Results, In both groups, the final sweat intensities of the hands subjected to the anodal current were significantly decreased in comparison with the initial values, regardless of whether the anodal current was applied to the right or left hand (P < 0.05). In contrast, the final sweat intensities of the other hands subjected to the cathodal current were not significantly decreased (P > 0.05). Conclusions, It can be concluded that the anodal current is more effective in reducing sweating on the palms when applied either to the right or left hand. In the treatment of palmoplantar or localized hyperhidrosis, the anodal current should be referenced first to treat the sweatier hand or foot, or a local hyperhidrotic area of the skin. The selection of the anodal current for one hand for the first five or seven sessions appears to be more effective than the use of polarity changes for each session. [source] | ||||||||||||||||||||||||||||