Blind Research Articles

The tomato WRKY-B transcription factor modulates lateral branching by targeting BLIND, PIN4, and IAA15.

Lateral branching is a crucial agronomic trait that impacts crop yield. In tomato ( Solanum lycopersicum ), excessive lateral branching is unfavorable and results in substantial labor and management costs. Therefore, optimizing lateral branching is a primary objective in tomato breeding. Although many genes related to lateral branching have been reported in tomato, the molecular mechanism underlying their network remains elusive. In this study, we found that the expression profile of a WRKY gene, WRKY-B (for WRKY-BRANCING), was associated with the auxin-dependent axillary bud development process. Wrky-b mutants generated by the CRISPR/Cas9 editing system presented fewer lateral branches, while WRKY-B overexpression lines presented more lateral branches than did wild-type plants. Furthermore, WRKY-B can directly target the well-known branching gene BLIND (BL) and the auxin efflux carrier gene PIN4 to activate their expression. Both the bl and pin4 mutants exhibited reduced lateral branching, similar to the wrky-b mutant. The IAA contents in the axillary buds of the wrky-b, bl, and pin4 mutant plants were significantly higher than those in the wild-type plants. In addition, WRKY-B can also directly target the AUX/IAA gene IAA15 and repress its expression. In summary, WRKY-B works upstream of BL, PIN4, and IAA15 to regulate the development of lateral branches in tomato.

Joint timing and frequency synchronization in coherent optical OFDM systems

In this paper, we review our joint timing and frequency synchronization algorithms in coherent optical orthogonal frequency division multiplexing (CO-OFDM) systems. We first present a timing estimation method by designing the pattern of the training symbol, whose timing metric has a sharp and clear peak, to ensure accurate timing offset (TO) estimation performance. Then we provide both data-aided (DA) and blind (BL) approaches to estimate the carrier frequency offset (CFO). For the DA algorithm, we utilize the same training symbol structure as the timing estimation does, while for the BL algorithm, we utilize the zero-subcarrier power (ZSP) to achieve full-range CFO estimation. Note that our joint timing and frequency synchronization approaches require only one OFDM symbol, which ensure not only the data transmission efficiency, but also the TO and CFO estimation performance. A modified BL ZSP algorithm is proposed to further improve the CFO estimation performance by taking the power average over a series of OFDM symbols. The effectiveness of the TO estimation algorithm, and both the DA and BL CFO estimation algorithms are verified and demonstrated in both simulations and experiments.

Carrier Frequency Offset Estimation for CO-OFDM: The Matched-Filter Approach

This paper proposes a novel carrier frequency offset (CFO) estimator for the coherent optical orthogonal frequency-division multiplexing (CO-OFDM) systems using the matched-filter (MF) concept. We consider an OFDM symbol with $N$ subcarriers so that the receiver takes $N$ time samples of the received noisy CO-OFDM signal. Our idea is to first append these $N$ received samples with $(L-1)N$ zeros at the end to get a sequence of $LN$ time samples. By taking the discrete Fourier transform of these $LN$ samples, we compute the spectrum of the CO-OFDM symbol at $LN$ discrete frequency points. We think of this spectrum as being made up of $L$ sets of $N$ points each, each set consisting of the frequency points $\lbrace \frac{2\pi }{LN}l, \frac{2\pi }{LN}l+\frac{2\pi }{N}, \ldots, \frac{2\pi }{LN}l+\frac{2\pi (N-1)}{N}\rbrace$ , for each value of $l$ , where $l=0,1,\ldots,L-1$ . Each set of $N$ points for one value of $l$ can be considered as the spectrum of the CO-OFDM symbol corresponding to one hypothesized value $\frac{2\pi }{LN}l$ of the CFO. The receiver can now obtain the maximum likelihood (ML) CFO estimate by determining the hypothesized value that best matches the spectrum of the CO-OFDM symbol received from the channel. In the case of data-aided (DA) ML estimation, we treat the OFDM symbol as a pilot symbol in which we know the data in all the subcarriers, and this pilot symbol is used as the reference signal for the MF. In the case of blind (BL) ML estimation, the data in all the subcarriers are unknown, and the receiver uses an OFDM symbol with no data modulation in all the subcarriers as the reference signal. After making the ML decision of the hypothesized value of the CFO, a fine search will be carried out to determine the actual value more accurately. It turns out only one step is necessary to locate the actual value of the CFO. The DA MF ML algorithm can achieve full-range (integral and fractional part) CFO estimation with high accuracy, while the BL MF ML algorithm has low computational complexity but focuses on the fractional CFO estimation only. We discuss the complexity and performance of this MF ML algorithm, and present simulation results to demonstrate the estimation error variance for 16-PSK/QAM modulations. The simulation results show that the estimation error variance of the DA MF ML algorithm can achieve the Cramer–Rao lower bound in the absence of the laser phase noise.

Manipulation of plant architecture and flowering time by down-regulation of the GRAS transcription factor SlGRAS26 in Solanum lycopersicum

Previous studies suggest that GRAS transcription factors act as essential regulators, not only in plant growth and development but also in response to biotic and abiotic stresses. Recently, 53 GRAS proteins have been identified, but only a few of them have been functionally studied in tomato. Here, we isolated a novel GRAS transcription factor SlGRAS26, its down-regulation generated pleiotropic phenotypes, including reduced plant height with more lateral shoots, internode length, leaf size, even leaflets, accelerated flowering transition and decreased trichome number. Transcription analysis showed that down-regulation of SlGRAS26 altered vegetative growth by suppressing gibberellin (GA) biosynthesis genes and activating the GA inactivating genes, thereby reducing endogenous GA content in transgenic plants. SlGRAS26 may regulate the initiation of lateral buds by regulating the expression of Blind (BL) and BRC1b. The earlier initiation of flower buds in transgenic lines may be controlled by significant up-regulation of SFT, CO1, SBP3, SBP13, and SBP15 genes, related to flowering time. These results demonstrate that SlGRAS26 may play a vital role in the initiation of lateral and inflorescence meristems in tomato.

Development and Complications of Blind and Ultrasound-Guided Percutaneous Liver Biopsy Techniques in Donkeys (Equus asinus)

The present study was designed to develop blind (BL) and ultrasound-guided (UG) liver biopsy (LB) techniques in donkeys (Equus asinus) and assess the complication rates of both techniques. Forty donkeys were included in this study. Based on the LB technique and biopsy site, the animals were allocated into four groups as BL biopsy at the 13th intercostal space (ICS) (BL13, n = 10), BL14 (n = 10), UG13 (n = 10), and UG14 (n = 10). All animals underwent liver ultrasonography prior to the biopsy procedure and then kept for 2-day observation period postbiopsy. The ultrasonographic thickness of the liver was higher at the 13th and 14th ICSs than the 12th and 15th ICSs (P < .05). The liver was partially covered by the lung at the most upper part of the 13th ICS. No mortality or major complications were observed. Follow-up ultrasonography revealed no serious complications, except a case in BL13 group exhibited a subcutaneous hematoma. The mean values of erythrocytic count and packed cell volume were significantly lowered in the BL13 group in comparison with their prebiopsy values (P < .05). All the biopsy specimens (40/40) were adequate for histopathological assessment. Mean specimen length and tissue fragmentation were significantly higher in the BL groups than UG ones (P < .001). In conclusion, percutaneous UG LB is a safe and accurate procedure and can be performed easily in donkeys. Blind LB at the 13th ICS is not recommended; however, it can be done safely at the 14th ICS.

Comparison of three techniques for paravertebral brachial plexus blockade in dogs

ObjectiveTo compare success and complication rates, based on staining of nerves and other structures, among three techniques of paravertebral brachial plexus blockade (PBPB) in dogs. Study designProspective randomized design. AnimalsA total of 68 thoracic limbs from 34 dogs. MethodsLimbs were randomly assigned to blind (BL) (n = 24), nerve stimulator-guided (NS) (n = 21) or ultrasound-guided (US) (n = 23) technique. Injections were made with 0.3 mL kg−1 of lidocaine mixed with new methylene blue. Time to perform each block and current used during NS technique were recorded. Dogs were anesthetized during the blocks and euthanized once completed. Dissections were performed to evaluate staining of nerves, spinal cord, mediastinum, pleura and vessels. An anova and Tukey adjustment for time, logistic regression for association between current and nerve staining and a generalized linear mixed model for staining of different structures were used. Significance was considered when p ≤ 0.05. ResultsThe median (range) number of nerves stained was 2 (0–4) with BL, 1 (0–3) with NS and 1 (0–4) with US guided technique. No significant differences in staining of C6, C8 and T1 or other structures were found among techniques. Nerve C7 was more likely to be stained by BL (p = 0.05). Time to perform the blocks was significantly different among techniques, with mean ± SD duration in minutes of 3.6 ± 1.8 with BL, 6.3 ± 2.7 with US and 12.2 ± 5 with NS. The most common complication was staining of the spinal cord (29%, 38% and 39% with BL, NS and US, respectively). ConclusionsSuccess rates were low and complication rates were relatively high, based on staining, with the three techniques. Clinical relevanceThe use of more advanced techniques for PBPB in dogs is not justified according to this study. Clinical significance of the complications encountered in this study should be evaluated.

CaBLIND regulates axillary meristem initiation and transition to flowering in pepper

Plant architecture is a major motif in plant diversity. The shape of the plant is regulated by genes that have been found to have similar or related functions in different species. However, changes in gene regulation or their recruitment to additional developmental pathways contribute to the wide range of plant patterns. Our aim was to unravel the genetic mechanisms governing the unique architecture of pepper (Capsicum annuum) and to determine whether these genetic factors have conserved functions in other plant species. We describe the pepper CaBLIND (CaBL) gene that is orthologous to the tomato (Solanum lycopersicum) BLIND (BL) and to the Arabidopsis thaliana REGULATOR OF AXILLARY MERISTEMS (RAX). We identified two allelic Cabl mutants that show dramatic reduction in axillary meristem initiation. In addition, Cabl exhibits late flowering and ectopic vegetative growth during the reproductive phase. Double-mutant and expression analyses suggest that CaBL functions independently of FASCICULATE, the pepper ortholog of SELF PRUNING in regulating sympodial growth, but is epistatic to FASCICULATE in controlling axillary meristem formation. Furthermore, CaBL operates independently of CaREVOLUTA and CaLATERAL SUPPRESSOR in regulating axillary branching. Our results provide evidence of CaBL's conserved function with BL and RAX genes in regulating axillary meristem initiation early in development. In addition, similar to BL but opposite to RAX, CaBL acts to promote the transition from vegetative to reproductive phase. However, in contrast to BL and RAX, CaBL is co-opted to play a role in suppressing vegetative growth during the reproductive phase in pepper.

Capturing Children and Young People's Perspectives to Identify the Content for a Novel Vision-Related Quality of Life Instrument

To describe a child-centered approach to identifying content for a novel self-report questionnaire for assessing vision-related quality of life (QoL) of visually impaired (VI) or blind (BL) children and young people. Questionnaire development. A stratified random patient sample of children and young people who are VI/BL (visual acuity in the better eye Snellen <6/18; logarithm of the minimum angle of resolution <0.51) as the result of any visual disorder, but in the absence of any other significant impairment, aged 10 to 15 years (N=49); and a convenience school-based sample of children and young people who are VI/BL and aged 10 to 17 years (N=29). Individual interviews were conducted with a stratified random sample of 32 children and young people, aged 10 to 15 years, who were VI/BL. The interviews followed a topic guide based on vision-related issues identified from a focus group of affected children and young people, combined with a literature review and consultations with professionals. Collaborative qualitative thematic analysis was undertaken and used to derive draft items of the instrument, using the children's own language wherever possible. Items were reduced, rephrased, and refined through individual consultation, as well as an expert reference group of children and young people who were VI/BL, and supplemented by the research team's consensus. A draft 47-item instrument. A total of 874 potential questionnaire items were initially generated spanning the following domains: social relations, acceptance, and participation; independence and autonomy; psychological and emotional well-being; future-aspirations and fears; functioning-home, school, and leisure; and treatment of eye condition. This was eventually reduced to a 47-item instrument with each item presented as a vignette describing a QoL issue from an "illustrative" child's perspective. Thus, the responding child reports on how much he/she is presently like and how much he/she wishes to be like that child, using a 4-point Likert-type scale. We demonstrate that a child-centered approach to identifying the content for a self-report vision-related QoL questionnaire is feasible. We suggest this approach is critical to accurately capturing children and young peoples' subjective perspectives on the impact of living with impaired vision.

A Survey of Visual Impairment and Blindness in Children Attending Four Schools for the Blind in Cambodia

Purpose: To identify the causes of blindness and severe visual impairment (BL/SVI) in children attending four schools for the blind in Cambodia and to provide spectacles, low vision aids, orientation and mobility training and ophthalmic treatment.Methods: Children < 16 years of age were recruited from all 4 schools for the blind in Cambodia. Causes of visual impairment and blindness were determined and categorized using World Health Organization methods.Results: Of the 95 children examined, 54.7% were blind (BL) and 10.5% were severely visually impaired (SVI). The major anatomical site of BL/SVI was the lens in 27.4%, cornea in 25.8%, retina in 21% and whole globe in 17.7%. The major underlying etiologies of BL/SVI were hereditary factors (mainly cataract and retinal dystrophies) in 45.2%, undetermined/unknown (mainly microphthalmia and anterior segment dysgenesis) in 38.7% and childhood factors in 11.3%. Avoidable causes of BL/SVI accounted for 50% of the cases; 12.9% of the total were preventable with measles being the commonest cause (8.1% of the total); 37.1% were treatable with cataracts and glaucoma being the commonest causes (22.6% and 4.8% respectively). More than 35% of children required an optical device and 27.4% had potential for visual improvement with intervention.Conclusion: Half of the BL/SVI causes were potentially avoidable. The data support the need for increased coverage of measles immunization. There is also a need to develop specialized pediatric ophthalmic services for the management of surgically remediable conditions, to provide optometric, low vision and orientation and mobility services. Genetic risk counseling services also may be considered.

Fostering Self-Help at a Distance for Adults with Visual Impairments

Susan D. Moisey and Don Golembiewski Participation in self-help groups has been associated with improved health and wellbeing among persons with chronic illnesses or disabilities. For example, older people with visual impairments (that is, those who are blind or have low vision) who participate in groups have been found to have greater coping ability and satisfaction with their activities and a more positive outlook on life than have older people who do not participate in such groups (Van Zandt, Van Zandt, & Wang, 1994). Weiss (1989) cited such benefits as learning to deal with problems and needs, developing coping strategies, combating isolation, and getting to know others. She concluded that with vision loss have embraced the concept of self-help as a valuable exchange of practical information and emotional support (p. 97). Recognizing these benefits, the Hadley School for the Bl ind developed the SelfHelp Groups series to encourage individuals with visual impairments to participate in self-help activities. The series consists of two courses. Each course is presented in four lessons (see Box 1), each consisting of a 60-minute audiotape. A facilitator who is available by telephone provides assistance and to students.

Sonority Constraints on Onset–Rime Cohesion: Evidence from Native and Bilingual Filipino Readers of English

Research in English suggests that syllables can be analyzed in terms of two subunits—the onset (defined as the initial consonant or consonant cluster) and the rime (the unit formed by the vowel and following consonant/s). This study investigated whether nonnative readers of English, which in the case of the present study were native Filipino speakers, also make use of onset–rime units, particularly when some features of their native language (namely infixation and reduplication) appear to foster no awareness of such units. In two lexical decision experiments, monosyllabic English words were presented, divided in between their first and second consonants (e.g., B LIND), at their onset–rime boundary (e.g., BL IND), or at their antibody boundary (e.g., BLI ND). Results indicated that the processes of infixation and reduplication did not affect the English word processing of native Filipino speakers. Rather, results for both native Filipino and native English speakers suggest that onsets composed of an “s + consonant” sequence (e.g., STAMP) are less cohesive than onsets comprised of a stop–liquid sequence (e.g., BLIND). It was concluded that not only may sonority constraints underlie onset cohesiveness, but that such phonetic properties may also be involved in visual word recognition.

視覚障害者の公共トイレ使用実態調査 : 公共トイレにおける安全性・利便性に関する研究 その1

In order to simplify the difficulty in using public lavatories for blind and vis ion-impaired persons, questionnaires and interview investigations were carried out. The result shows that 75.1% of blind and vision-impaired persons could use a lavatory alone, however, 85.2% of men and 97.0% of women feel inconvenience. The most difficult tasks are "finding a lavatory", "distinguishing between men and women" and "flushing the toilet". "Finding the urinal" and "finding the washstand" are particularly difficult for bl ind persons. A standard for planning is requested in order to simplify the use of lavatory facilities for blind and vision-impaired persons.

The whorl-specific action of a petunia class B floral homeotic gene.

GREEN PETAL (GP) is thought to be a petunia class B floral homeotic gene, because the gp mutant flower displays a severe homeotic conversion of petals into sepals in the second whorl. However, since the third whorl stamens remain unaffected in the gp null mutant, gp is different from class B mutants in Arabidopsis and Antirrhinum, which also show a conversion of the third whorl stamens into the carpelloid tissue. BLIND (BL) is thought to be a petunia class A floral homeotic gene, because the bl mutant flower displays homeotic conversions of sepals into the stigmatoid tissue in the first whorl and of the corolla limb into antheroid structures in the second whorl. A double mutant line homozygous for both bl and gp mutations was constructed. The bl gp double mutant flower displays homeotic conversions of sepals into the stigmatoid tissue in the first whorl and of the corolla limb into antheroid structures with stigmatoid tips in the second whorl. In the third and fourth whorls of the mutant flower, organs remained unchanged. In the gp flower, a petunia B-type gene FBP1 is expressed strongly in the third whorl organs, but much more weakly in the second whorl organs. In the bl gp flower, FBP1 was found to be expressed strongly in the second whorl organs as well as in the third whorl organs. Petunia has a class B gene other than GP that determines organ identities, both in the second and third whorls of the double mutant flower, and the action of the postulated class B gene (here called PhBX) is prevented by the BL gene in the second whorl of the gp flower. PhBX appears to be a gene that specifically interacts with the FBP1 gene, and is involved in the up-regulation of FBP1.

Causes of childhood blindness in east Africa: results in 491 pupils attending 17 schools for the blind in Malawi, Kenya and Uganda.

Pupils attending 12 schools for the blind in Malawi, 3 schools in Kenya and 2 schools in Uganda were examined to determine the causes of severe visual impairment or blindness (visual acuity in the better eye of less than 6/60). A total of 491 pupils aged 3-22 years was examined. Visual acuity was measured in each eye using a Snellen E chart. The anatomical site of abnormality and underlying cause of visual loss were determined by clinical examination for each eye, and for the child. Information was recorded on a standard reporting form (the WHO/PBL Eye Examination Record for Children with Blindness and Low Vision). Data were analysed for those aged less than 16 years using a database which accompanies the form. Preventable and treatable causes were identified. 260 pupils aged 5-20 years were examined in Malawi, 163 pupils aged 3-19 years were examined in Kenya and 68 pupils aged 6-22 years were examined in Uganda. Of the 491 students included in the study 309 (62.9%) were blind (BL) and 69 (14.1%) were severely visually impaired (SVI). 244 were aged less than 16 years and had SVI/BL. In these 244 children 35.2% of visual loss was due to corneal pathology, 13.5% was due to cataract and 14.8% to diseases of the retina. Corneal pathology, attributed to vitamin A deficiency and measles infection in the majority, was responsible for proportionally more SVI/BL in students in Malawi than in Uganda or Kenya.(ABSTRACT TRUNCATED AT 250 WORDS)

Differential Responsiveness of the Reproductive System of Blind or Melatonin‐Treated Male Hamsters to Injections of Gonadotrophin‐Releasing Hormone (GnRH) and/or Prolactin

The combination of pituitary grafts and daily injections of gonadotrophin-releasing hormone (GnRH) completely prevents gonadal atrophy in blind (BL) and melatonin (Mel)-treated male hamsters. In order to avoid potential problems associated with the use of pituitary grafts and further define the interactions between prolactin (PRL) and GnRH in preventing reproductive regression, we injected various doses of each hormone either alone or in combination into BL or Mel-treated male hamsters. In another experiment, BL hamsters received either weekly beeswax implants of estradiol benzoate (EB) (1 mg) alone or EB implants in combination with daily injections of GnRH (2 micrograms). In each experiment the hamsters were BL and/or treated with hormones for 10 wk. Either GnRH (8 micrograms) or PRL (5 micrograms) per d partially prevented gonadal atrophy in BL hamsters. However, increasing doses of GnRH plus PRL were more effective than either hormone alone in preventing gonadal atrophy. The combined effect of these hormones was greater than the algebraic sum of their individual effects. Injections of either GnRH or PRL alone resulted in a significant maintenance of gonadal and accessory organ size in Mel-treated animals. The combination of GnRH and PRL resulted in virtually complete maintenance of testicular weight while the accessory sex organs remained atrophic. The combined effect of these hormones was equivalent to the algebraic sum of their individual effects. The treatment of BL animals with EB implants with or without GnRH did not prevent reproductive regression in spite of elevated serum PRL levels. In conclusion, the effects of GnRH and PRL were synergistic in BL hamsters and additive in Mel-treated animals. The data suggest that there is a differential responsiveness of BL v. Mel-treated hamsters to the individual as well as the combined actions of GnRH and PRL.