137,242 research outputs found
More on AC^0[oplus] and Variants of the Majority Function
No full textIn this paper we prove two results about AC^0[oplus] circuits.
(1) We show that for d(N) = o(sqrt(log N/log log N)) and N {0,1}} such that
- f_N has uniform AC^0 formulas of depth d and size at most s;
- f_N does not have AC^0[oplus] formulas of depth d and size s^epsilon, where epsilon is a fixed absolute constant.
This gives a quantitative improvement on the recent result of Limaye, Srinivasan, Sreenivasaiah, Tripathi, and Venkitesh, (STOC, 2019), which proved a similar Fixed-Depth Size-Hierarchy theorem but for d << log log N and s << exp(N^(1/2^Omega(d))).
As in the previous result, we use the Coin Problem to prove our hierarchy theorem. Our main technical result is the construction of uniform size-optimal formulas for solving the coin problem with improved sample complexity (1/delta)^O(d) (down from (1/delta)^(2^O(d)) in the previous result).
(2) In our second result, we show that randomness buys depth in the AC^0[oplus] setting. Formally, we show that for any fixed constant d >= 2, there is a family of Boolean functions that has polynomial-sized randomized uniform AC^0 circuits of depth d but no polynomial-sized (deterministic) AC^0[oplus] circuits of depth d.
Previously Viola (Computational Complexity, 2014) showed that an increase in depth (by at least 2) is essential to avoid superpolynomial blow-up while derandomizing randomized AC^0 circuits. We show that an increase in depth (by at least 1) is essential even for AC^0[oplus].
As in Viola’s result, the separating examples are promise variants of the Majority function on N inputs that accept inputs of weight at least N/2 + N/(log N)^(d-1) and reject inputs of weight at most N/2 - N/(log N)^(d-1)
Partially-erupting prominences: a comparison between observations and model-predicted observables
No full text<p><b>Aims:</b> We investigate several partially-erupting prominences to study their relationship with other CME-associated phenomena and compare these observations with observables predicted by a model of partially-expelled-flux-ropes (Gibson & Fan 2006a, ApJ, 637, L65; 2006b, J. Geophys. Res., 111, 12103).</p>
<p><b>Methods:</b> We studied 6 selected events with partially-erupting prominences using multi-wavelength observations recorded by the Extreme-ultraviolet Imaging Telescope (EIT), Transition Region and Coronal Explorer (TRACE), Mauna Loa Solar Observatory (MLSO), Big Bear Solar Observatory (BBSO), and Soft X-ray Telescope (SXT). The observational features associated with partially-erupting prominences were then compared with the predicted observables from the model.</p>
<p><b>Results:</b> The partially-expelled-flux-rope (PEFR) model can explain the partial eruption of these prominences, and in addition predicts a variety of other CME-related observables that provide evidence of internal reconnection during eruption. We find that all of the partially-erupting prominences studied in this paper exhibit indirect evidence of internal reconnection. Moreover, all cases showed evidence of at least one observable unique to the PEFR model, e.g., dimmings external to the source region and/or a soft X-ray cusp overlying a reformed sigmoid.</p>
<p><b>Conclusions:</b> The PEFR model provides a plausible mechanism to explain the observed evolution of partially-erupting-prominence-associated CMEs in our study.</p>
Habrocestum togansangmai Kadam & Tripathi 2023, sp. nov.
No full textHabrocestum togansangmai Kadam & Tripathi 2023, sp. nov. Figures 3, 4 A-E, 5 (Ƌ only) Etymology. The species group name is a patronym honouring Pa Togan Nengminja Sangma, a brave freedom fighter from the State of Meghalaya, who fought against the British army. Type material. Holotype: Ƌ (NRC-AA-7689) from INDIA: Meghalaya: South West Khasi Hills: Nongnah village (25°16'03''N, 91°19'12''E; 992 m alt.), 07 April 2022, Gautam K. leg., from ground, by hand. Deposited in the National Centre for Biological Sciences Research Collections (NRC), Bengaluru, India. Ƌ, same data as holotype, except South Garo Hills, Siju Bird Sanctuary (25° 20.501'N, 90°40.997'E; 162 m alt.), photographic record by Arpita D., specimen not collected (data used with permission). Diagnosis. Males of Habrocestum togansangmai are closely related to the males of H. ohiyaensis Kanesharatnam & Benjamin 2016 as both share an almost straight, thin embolus emerging from below the tegular layer, but can be distinguished from the latter species by a tegulum without a proximal lobe (vs. present in H. ohiyaensis), a short, triangular protrusion at distal end of the tegulum (vs. absent in H. ohiyaensis), a short and straight RTA (vs. medium sized and hooked-shaped in H. ohiyaensis) (compare Figures 3D–E with Kanesharatnam & Benjamin 2016, fig. 9A–F). Description. Male (holotype, Figure 3A–C, F, colouration in alcohol): carapace, eye field orangish red, clypeus and chelicerae brown; labium, endites, sternum, legs and spinnerets pale yellow, opisthosoma dark orange, distinctly marked with irregular shaped blotches having black hairs. Carapace covered with scattered fine black hairs; ocular region covered with orangish red hairs. Cheliceral promargin with two closely spaced, tiny teeth; retromargin with single bifurcated tooth (Figure 3F). Opisthosoma oval, hirsute. Leg I longest, with distinct black patches at the posterior end of segments. Body length. 2.95. Carapace 1.69 long, 1.26 wide. Opisthosoma 1.22 long, 0.96 wide. Ocular area 0.88 long, 1.06 wide. Eye sizes and interdistances: AME 0.36, ALE 0.23, PME 0.06, PLE 0.20; AME–AME 0.01, AME–ALE contiguous, PME–PME 0.98, ALE–ALE 0.75, PME–PLE 0.12, PLE–PLE 0.84, ALE–PME 0.23, ALE-PLE 0.40. Length of chelicerae 0.58. Clypeus height at AMEs 0.07. Sternum 0.64 long, 0.51 wide. Length of pedipalp and legs: pedipalp 1.39 [0.47, 0.24, 0.13, 0.55], I 3.77 [1.14, 0.59, 0.96, 0.71, 0.37], II 2.52 [0.82, 0.38, 0.54, 0.49, 0.29], III 2.91 [0.91, 0.34, 0.58, 0.73, 0.35], IV 3.08 [1.08, 0.45, 0.54, 0.70, 0.31]. Leg formula: 1432. Spination of pedipalp: femur pld 1 do 2, patella pl 1 do 1, tibia pld 1 do 2 rld 1, tarsus/cymbium pl 1 do 2 rl 1 rld 1; legs: femur I & IV do 3, II pl 1 do 3, III do 3 rld 2; patellae I–II 0, III pl 1 rl 1, IV pl 1; tibia I plv 3 rlv 3, II pl 1 plv 3 rlv 3, III pl 1 pld 1 plv 1 rl 1 rld 1 rlv 1, IV pl 1 pld 1 plv 1 rl 1 rld 1 rlv 2; metatarsus I plv 2 rlv 2, II pl 1 plv 2 rlv 2, III pl 1 pld 2 plv 1 rl 2 rld 2 rlv 2, IV pl 1 pld 2 plv 1 rl 1 rld 2 rlv 2; tarsi I–IV 0. Pedipalp (Figure 3D–E): cymbium hirsute, RTA short, thumb-like, with rounded apex directed at 11-o’ clock retrolaterally (Figure 3E). Tegulum moderately swollen, with short, triangular protrusion at distoretrolateral end (Figure 3D). Embolus thin, moderately long, originating distoprolaterally, with pointed apex directed at 1-o’ clock ventrally (Figure 3D). Female. Unknown. Distribution. Known from the South West Khasi Hills and South Garo Hills District of Meghalaya (Figures 4E, 5).Published as part of Kadam, Gautam, Tripathi, Rishikesh & Sudhikumar, Ambalaparambil Vasu, 2023, Three new jumping spiders from northeastern India (Araneae: Salticidae: Hasariini: Habrocestum), pp. 1-10 in Peckhamia 295 (1) on page
Rhenefictus wandae Caleb & Sanap & Tripathi & Sampathkumar & Dharmaraj & Packiam 2022, comb. n.
No full textRhenefictus wandae (Wang & Li, 2021) comb. n. Rhene wandae Wang & Li, 2021: 149, figs 16A–C, 17A–D (D ♂). Rhenefictus tropicus Logunov, 2021: 1044, figs 120–126 (D ♂); holotype ♂ in MMUE, not examined; syn. n. Comments. Rhene wandae Wang & Li, 2021 was described based on the holotype male and the paratype male from Xishuangbanna, Yunnan, China. Rhenefictus tropicus Logunov, 2021 was described based on the holotype male from the Tuyen Quang Province in northern Vietnam. While comparing the illustrations of both species, it is evident that they depict the same species. The unique male palp with the long whip-like, coiled embolus lacking a terminal apophysis (cf. figs 120–126 in Logunov (2021) with figs 16A–C, 17A–D in Wang & Li (2021)) is a diagnostic characteristic of the newly erected genus Rhenefictus Logunov, 2021. Despite both descriptions being published in 2021, the paper by Wang & Li appeared in October, whereas that of Logunov in November. Therefore, the name Rhene wandae has a priority over R. tropicus Logunov, 2021, and the latter is to be considered a junior synonym of the former. Yet, the validity of the newly erected, monotypic genus Rhenefictus remains unquestioned, and thus Rhene wandae is to be transferred to this genus: Rhenefictus wandae (Wang & Li, 2021) comb. n. Finally, despite the newly established synonymy and based on Article 67.1.2 of the ICZN, Rhenefictus tropicus Logunov, 2021 remains the type species of Rhenefictus, and is now regarded as a synonym of Rhene wandae Wang & Li, 2021. Distribution. China, northern Vietnam (Wang & Li, 2021; Logunov 2021: sub Rhenefictus tropicus; WSC, 2022) (Fig. 72).Published as part of Caleb, John T. D., Sanap, Rajesh V., Tripathi, Rishikesh, Sampathkumar, M., Dharmaraj, Jayaraman & Packiam, Soosaimanickam Maria, 2022, Taxonomic notes on some South and Southeast Asian members of the genus Rhene Thorell, 1869 (Aranei, Salticidae, Dendryphantini), pp. 389-407 in Zootaxa 5125 (4) on page 403, DOI: 10.11646/zootaxa.5125.4.3, http://zenodo.org/record/645090
Timing of initiation of reverse displacement on the Taranaki Fault, northern Taranaki Basin: Constraints from the on land record (Oligocene Te Kuiti Group)
No full textStructures associated with the wedge of basement overthrust into Taranaki Basin along the Taranaki Fault, are regarded as hydrocarbon plays and have been tested by drilling through the tip of the overthrust. The timing of initiation of reverse displace ment on Taranaki Fault is difficult to interpret from available seismic reflection data across it because the evidence has been masked by later movements. The record from the basin, as summarised in King & Thrasher (1996), suggests that the fault evolved from normal to reverse character during the mid-Oligocene. This was inferred from formation of a foredeep parallel to, and west of, Taranaki Fault and a marked increase in its paleo-water depth, as indicated by foraminiferal assemblages of Late Oligocene age.
A comprehensive re-assessment of the lithostratigraphy and sequence stratigraphy of the Late Eocene-Oligocene Te Kuiti Group exposed on land east of Taranaki Fault in central-western North Island, between Port Waikato and Awakino, provides new constraints on the early history of Taranaki Fault displacement. New age control has been achieved by a review of existing foraminiferal biostratigraphy combined with determination of Sr isotope ages from macrofossil samples. Six unconformity-bound sequences have been identified and mapped within the Te Kuiti Group. A major subaerial unconformity between sequences TK3 and TK4 combined with a basinward shift in the position of onlap for sequence TK4 indicate a dramatic change in stratigraphic development and basin dynamics during the mid-upper Whaingaroan at c. 29 Ma, corresponding to the change from mild extension (sag basin) to shortening across the Taranaki Fault Zone. We consider sequences TK4 – TK6 to each represent tectonic cycles of subsidence and basin inversion and we attribute the origin of these cycles to periodic locking of the Taranaki Fault décollement in underlying Murihiku basement, the accumulating strain causing uplift in the basin east of the fault zone, followed by free displacement, relaxation in the upper crust and subsidence. A 1st order model is presented of the Late Oligocene to earliest Miocene vertical and horizontal displacement of basement on the Taranaki Fault Zone for a west –east transect through Awakino. It implies that the mid- to Late Oligocene displace¬ment on the fault zone in the vicinity of Awakino was episodic, and that the thrust belt was narrow (c. 15 km). North of Kawhia Harbour there will have been a different displacement history with most of the total displacement occurring during the devel opment of the c. 29 Ma unconformity at the base of Sequence TK4, whereas to the south between Awakino and Kawhia Harbour the majority of the total displacement occurred during the Otaian and at the end of it. The model also shows that the start of reverse/thrust displacement on Taranaki Fault must have involved the development of a completely new fault trace(s), rather than involving a change of sense of movement on the pre-existing normal fault. The Manganui Fault is part of the Taranaki Fault Zone and probably became active at c. 27 Ma during development of the unconformity between sequences TK4 & TK5. The model presented here has been validated against the subsurface Oligocene stratigraphy in Taranaki Basin
Rhene pallida Caleb & Sanap & Tripathi & Sampathkumar & Dharmaraj & Packiam 2022, comb. n.
No full textRhene pallida (Thorell, 1895) comb. n. Figs 42–56, 72 Zeuxippus pallidus Thorell, 1895: 333 (D ♀); Prószyński, 1984: 123 (♀); Żabka, 1985: 456, figs 639–645 (♀, D ♂). Rhene argentata Wesołowska, 1981: 47, figs 5–8 (D ♀). Rhene decoratus Tikader, 1977: 276, figs 4–6 (D ♀); holotype ♀ in NZC-ZSI, examined; syn. n. Rhene pantharae Biswas & Biswas, 1992: 399, figs 29–31 (D ♀); holotype ♀ in the NZC-ZSI, examined; syn. n. For a complete list of taxonomic references see WSC (2022). Types. Rhene decoratus Tikader, 1977: Holotype ♀ (NZC-ZSI) from INDIA, Maharashtra, Poona (presently Pune) Distr., Karla Govt. Rest House, 04.11.1963, leg. B.K. Tikader. Paratype: 1 ♀ (NZC-ZSI), together with the holotype. Rhene pantharae Biswas & Biswas, 1992: Holotype ♀ (NZC-ZSI 5369/18) from INDIA, West Bengal, Nadia Distr., Ranaghat, 16.02.1986, leg. K. Biswas. Comments. R. decoratus Tikader, 1977 was originally described from Maharashtra and was later recorded from West Bengal (Tikader & Biswas, 1981; Roy et al., 2016) and R. pantharae Biswas & Biswas, 1992 was described from West Bengal (Biswas & Biswas, 1992). Based on the detailed examination of the types of both species, they were found to be identical to Rhene pallida (Thorell, 1895) comb. n. in the following characters: the abdominal colour pattern with transverse black streaks and the genitalia morphology with comma-shaped sclerotized rims and central epigynal pocket; proximal portion of insemination ducts membraneous and bent S-like, mid-portion strongly sclerotized, running parallel along the median portion longitudinally; small spermathecae (cf. Figs 42–48 and Figs 51–55 with figs 5–8 in Wesołowska (1981), illustrations in Proszynski (1984: 123) and figs 643–645 in Zabka (1985)). Therefore, both the species R. decoratus and R. pantharae are treated as junior synonyms of R. pallida. Distribution. Bangladesh, Myanmar, China, Vietnam (WSC, 2022), India (Maharashtra, West Bengal) (Fig. 72).Published as part of Caleb, John T. D., Sanap, Rajesh V., Tripathi, Rishikesh, Sampathkumar, M., Dharmaraj, Jayaraman & Packiam, Soosaimanickam Maria, 2022, Taxonomic notes on some South and Southeast Asian members of the genus Rhene Thorell, 1869 (Aranei, Salticidae, Dendryphantini), pp. 389-407 in Zootaxa 5125 (4) on pages 398-402, DOI: 10.11646/zootaxa.5125.4.3, http://zenodo.org/record/645090
Essentials of medical pharmacology / K.D. Tripathi, MD, ex-director-professor and head of Pharmacology, Maulana Azad Medical College and associated LN and GB Pant Hospitals, New Delhi, India.
No full textIncludes bibliographical references (pages 971-973) and index.xvi, 1002 pages
Synthesis and Antitubercular Evaluation of Diverse Glycosylated Ureas from D-Glucose
No full textDedicated to Dr. Rama P. Tripathi, Former Chief Scientist at CSIR-Central Drug Research Institute, Lucknow, India, for his extraordinary contribution to “Drug development against Tuberculosis
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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