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Recent advances in radio-frequency system-on-chip technology have provided mm-wave fusion plasma diagnostics with the capability to overcome major challenges such as space inefficiency, inflexible installation, sensitivity, susceptibility to EMI, and prohibitively high cost of conventional discrete component assemblies as higher imaging resolution and data accuracy are achieved by increasing the number of channels. Nowadays, shrinking transistor gate lengths on fabrication techniques have enabled hundreds of GHz operation, which is suitable for millimeter-wave diagnostics on current and future tokamaks. The Davis Millimeter Wave Research Center (DMRC) has successfully developed V-band (55-75 GHz) transmitter and receiver chips for Microwave Imaging Reflectometer (MIR) instruments. The transmitter can illuminate 8 different frequencies simultaneously within 55-75 GHz. Moreover, the receiver has the capability to amplify the reflected signal (>30 dB) while offering 10-30× reduction in noise temperature compared to current MIR instruments. Plasma diagnostics requires ultra-wideband (more than 20 GHz) operation which is approximately nine times wider bandwidth than the recent commercial impetus for communication systems. Current efforts are underway for gallium-arsenide monolithic microwave integrated circuit receiver chips at W-band (75-110 GHz) and F-band (90-140 GHz) permitting measurements at higher toroidal magnetic fields.

We present the development of a low-loss, high-power, and ferriteless balun that operates over 0.1-1.6 GHz bandwidth. The proposed balun employs a novel compensated circuit, a single quarter-wave semirigid coaxial cable and an on-board inductor on a thermoset ceramic board to achieve high power and ultrawide bandwidth performance. The experimental results show that the balun achieves a measured average insertion loss of less than 0.5 dB and return loss of better than 10 dB from 100 MHz to more than 1.6 GHz. Within the measured bandwidth, the amplitude and phase imbalances are within ±1 dB and ±5°, respectively. Multiphysics analysis and high-power measurements demonstrate that the balun can handle more than 600 W and above at 1.6 GHz. To the best of our knowledge, the reported balun has the highest measured power handling capability per the largest 16:1 bandwidth ratio to date.

Electron cyclotron emission (ECE) imaging is a passive radiometric technique that measures electron temperature fluctuations; and microwave imaging reflectometry (MIR) is an active radar imaging technique that measures electron density fluctuations. Microwave imaging diagnostic instruments employing these techniques have made important contributions to fusion science and have been adopted at major fusion facilities worldwide including DIII-D, EAST, ASDEX Upgrade, HL-2A, KSTAR, LHD, and J-TEXT. In this paper, we describe the development status of three major technological advancements: custom mm-wave integrated circuits (ICs), digital beamforming (DBF), and synthetic diagnostic modeling (SDM). These have the potential to greatly advance microwave fusion plasma imaging, enabling compact and low-noise transceiver systems with real-time, fast tracking ability to address critical fusion physics issues, including ELM suppression and disruptions in the ITER baseline scenario, naturally ELM-free states such as QH-mode, and energetic particle confinement (i.e. Alfvén eigenmode stability) in highperformance regimes that include steady-state and advanced tokamak scenarios. Furthermore, these systems are fully compatible with today's most challenging non-inductive heating and current drive systems and capable of operating in harsh environments, making them the ideal approach for diagnosing long-pulse and steady-state tokamaks.

We demonstrate the design of a linear and high efficient power amplifier (PA) by using different gate bias voltages for parallelly combined Gallium Nitride (GaN) high electron mobility transistors (HEMTs). The experimental results show that the linearized PA achieves the gain flatness of 0.3 dB over a 35 dB power range and has a measured sharp output power at 1 dB compression point (P1dB) of 38.5 dBm, less than 2 dB below the saturated power (PSAT). The measured adjacent channel power ratio (ACPR) of the proposed linearized PA shows up to 8 dB improvements over the PA biased ∼class A (47% Idss).

A K-band monolithic microwave integrated circuit (MMIC) transmit and receive (T/R) single pole double throw (SPDT) switch with low insertion loss, high isolation and ultra-high output power is demonstrated using 0.15-μm Gallium Arsenide (GaAs) technology. A shunt field effect transistor (FET) configuration is used to provide low insertion loss and high isolation while the stacked-FET is employed to improve power handling capability. The novel GaAs switch exhibits a minimum measured insertion loss of 1.4 dB and less than 2.5 dB from 22 GHz to 26 GHz as well as 44 dB isolation. The measured input 1-dB power compression point (P1,dB) exceeds 4 W.

The authors present the design and development of a two stage Doherty power amplifier (DPA) in the Ka-band. The amplifier is fabricated in a 0.15-μm gallium arsenide (GaAs) pseudomorphic high electron mobility transistor (pHEMT) process. The DPA has a centre frequency of 26.6 GHz, a measured small signal gain of 10.5 dB, output power at 1-dB compression point (P1 dB) of 26.9 dBm, maximum power added efficiency (PAE) of 42%, and PAE of 32% at 6 dB back-off power. To the best of the author's knowledge, this DPA is the first millimetre-wave (mm-wave) power amplifier to achieve a record 32% PAE at 6-dB back-off power from 26.9 dBm at Ka-band.

An ultra-compact watt-level Ka-band monolithic microwave integrated circuit (MMIC) power amplifier (PA) is demonstrated using a 0.15 μm Gallium Arsenide (GaAs) stacked field effect transistor (stacked-FETs) configuration. The fabricated PA exhibits 31.5 dBm output power, 17 dB gain and 33% power added efficiency (PAE). The bandwidth is from 26 GHz to 31 GHz. The PA achieves 0.7 Watt/mm2 power density at 28 GHz. To the best of our knowledge, this PA achieves the highest power density among reported GaAs Ka-band PAs.

A subsection of the radiating spiral arm, placed in parallel, induces a bandstop response at a notch frequency proportional to the resonant length of the strip. Detailed parametric study on the effect of variation of design parameters for an Archimedean spiral antenna and the resonant parallel strip (RPS) is presented. Empirical analysis on phase velocity on the radiating spiral arms allows characterization of RPS in terms of its resonant length. Identified systematic relation between design parameters and filter response is applied to design an antenna for the 3.1-10.5 GHz operating band with the notch response over the IEEE 802.11a band, 5.15-5.95 GHz. Successful implementation is demonstrated through performance comparison between simulated and experimental results.

In this study, the authors present the design and development of a novel ultra-wideband coupled-line balun on a multilayer liquid crystal polymer substrate. The balun is designed using a quarter wavelength (λ/4) asymmetric broadside coupled line. The defected ground structure and a lumped phase compensation circuit are developed to achieve wide bandwidth performance for the balun. The balun has a measured bandwidth ratio of 23:1, from 80 to 1860 MHz. Within the operating bandwidth, the experimental results demonstrate that the balun achieves an input return loss of better than 10 dB, an insertion loss of better than 1 dB, an amplitude imbalance of better than ±0.4 dB and a phase imbalance of better than ±10°. The size of the balun is 40.64 mm × 40.64 mm or 0.22 λg × 0.22 λg, where λg is the guided wavelength at the centre frequency of 970 MHz.

We present the design and development of a compact wide stopband bandpass filter using novel quasi-lumped LC resonators on a defected ground structure. The resonators are built on a multilayer organic substrate and are coupled to external circuits by shunt-inductive impedance inverters. Experimental results show that the filter has a center frequency of 960 MHz and a 3 dB fractional bandwidth of 8%. The filter has a wide stopband that has an out-of-band rejection of better than 30 dB up to five times of the center frequency. The size of the filter is 5.4 mm × 27 mm or 0.027λg × 0.132 λg, where λg is guided wavelength at 960 MHz. © 2014 IEEE.

We present the design and development of a compact, broadband balun based on a quasi-lumped LC transformer. The balun is constructed on a multilayer liquid crystal polymer substrate. The balun has a wide range of operating frequency from 0.9 to 3.6 GHz. Within this operating band, the balun achieves a measured insertion loss of less than 1 dB, a measured return loss of better than 10 dB, a measured amplitude imbalance of less than 1 dB and a measured phase imbalance less than 7°. This balun has an extremely compact size of 2 × 2.5 mm2. Copyright © 2013 Wiley Periodicals, Inc.

We present the design and development of dual-polarized aperture coupled stacked patch antennas with substrate embedded air cavities. The antennas, targeted for operation in the W-band (75 - 110 GHz), are realized in amultilayer organic hybrid substrate utilizing both Kapton and liquid crystal polymer (LCP). Balanced and unbalanced feedlines are investigated in order to improve isolation and mitigate coupling between orthogonal polarized ports. Measured results for the single antenna element show good performance with a beamwidth of 90° and a 2.6:1 VSWR bandwidth of 23 GHz, and isolation of better than 17.8 dB. An eight-element linear array is also designed, fabricated and tested. The antenna array achieves a beamwidth of 13 with a 2.3:1VSWR bandwidth of 7.2 GHz. Pattern measurements were achieved utilizing a millimeter-wave diode detector circuit implemented directly on the antenna substrate. © 2013 IEEE.

Background: The Annam Stream Frog Hylaranaannamitica was recently discovered from north and central Vietnam and Laos by Sheridan and Stuart (2018). Knowledge of its natural history is virtually lacking., New Information: In this study, we provide an extended morphological description of Hylaranaannamitica , based on newly-collected specimens from Vu Quang National Park, Ha Tinh Province, Vietnam. In addition, we present data on the diet of Hylaranaannamitica , based on stomach content analyses of 46 individuals (32 males and 14 females) and compare prey selection between sexes. We found a total of 37 prey categories with 339 items, comprising 327 items of invertebrates, two items of vertebrates and 10 unidentified in the stomachs of H.annamitica . The most important (IRI) groups amongst the prey of H.annamitica were Coleoptera (17.19%), followed by Mantodea (14.78%), Orthoptera (11.26%), Lepidoptera (11.13%), Araneae (10.0%) and Blattodea (9.87%). There was an overlap of 45.63% in the diet between males and females and, in both sexes, the trophic spectrum was similar, predominantly consisting of Araneae, Coleoptera, Dermaptera, Diptera, Hemiptera, Hymenoptera, Isoptera, Lepidoptera, Mantodea and Orthoptera., (Duong Anh Thi To, Minh Duc Le, Hang Thu Thi Le, My Tra Phan, Anh Thi Ngoc Ho, Truong Quang Nguyen, Thomas Ziegler, Anh Van Pham.)

A new species of the genus Scincella Mittleman, 1950 is described from northern Vietnam based on morphological and molecular evidence. Scincellatruongi sp. nov. is characterized by a combination of the following characters: size medium (SVL up to 59.4 mm); primary temporals 2; external ear opening without lobules; loreals two; supralabials seven or eight; infralabials six or seven; nuchals in three pairs; midbody scales in 28 rows; dorsal scales smooth, in six rows across the back; paravertebral scales 60-67, not widened; ventral scales in 60-70 rows; ten smooth lamellae beneath finger IV and 13-15 beneath toe IV; toes not reaching to fingers when limbs adpressed along body; dorsal surface of body and tail bronze brown with few black spots, a dark stripe running from nostril to eye and extending from posterior corner of eye along upper part of flank to the middle of the tail. In the phylogenetic analyses, the new species is recovered as an independent lineage with no clear sister taxon and at least 17.3% genetic divergence from other species in the genus based on a fragment of the mitochondrial COI gene., Competing Interests: The authors have declared that no competing interests exist., (Anh Van Pham, Thomas Ziegler, Cuong The Pham, Thao Ngoc Hoang, Hanh Thi Ngo, Minh Duc Le.)

Objective: Addressing the disproportionate use of school detentions and suspensions among Black youth is crucial for reducing educational and health disparities across the life span. Yet, few studies have explored external factors beyond school or individual characteristics as potential contributors to school discipline disparities, such as state-level racial bias and neighborhood opportunity., Method: A subsample from the larger Adolescent Brain Cognitive Development (ABCD) Study was used (n = 8,668; mean age at baseline = 9.5 years; 71% White; 29% Black). Anti-Black racial bias was measured using state-level indicators of racial prejudicial attitudes. Neighborhood opportunity was measured using census tract indicators within the education, health care, and social/economic domains. Logistic regression was used to examine risk of receiving a detention/suspension by the fourth wave of the study., Results: Black youth had significantly higher detention/suspension rates than White youth, which could not be explained by teacher- or caregiver-reported externalizing concerns or by family characteristics. As hypothesized, social/economic indicators of neighborhood opportunity moderated the association between state-level racial bias and school discipline among Black youth, but not among White youth. Black youth living in states with greater racial bias were at higher risk for receiving school discipline when living in neighborhoods with more social/economic opportunities. In contrast, Black youth were at high risk for school discipline when living in neighborhoods with the lowest levels of opportunity regardless of state-level racial bias., Conclusion: Place-based characteristics appear to play a key role in explaining the inequitable use of school discipline among Black youth compared with White youth., (Copyright © 2025 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.)

Background: The White-lipped Treefrog Zhangixaluspachyproctus Yu, Hui, Hou, Wu, Rao & Yang, 2019 was previously confused with Zhangixalussmaragdinus (Blyth, 1852). Records of Zhangixalussmaragdinus from Yunnan (China), Vietnam and Thailand were recognised as a misidentification and this taxon was subsequently described as a new species, based on morphological and molecular evidence. This species is currently known from southern China, Thailand, Laos and Vietnam. However, knowledge about its natural history and feeding ecology is virtually lacking., New Information: We herein report a newly-discovered population of Zhangixaluspachyproctus from Lang Son Province, northern Vietnam. In addition, we provide novel data about the diet of Z.pachyproctus , based on stomach content analyses of 38 individuals (37 males and one female). A total of 26 prey categories with 681 items were found in the stomachs of Z.pachyproctus . The dominant prey items of the species were Orthoptera (Acrididae, Tettigoniidae), Coleoptera (Languriida, Leiodidae, larvae, other Coleoptera), Mantodea (Mantidae) and Blattodea (Blaberidae, Blattidae, other Blattodea). Coleoptera (Coccinellidae, Cupedidae, Elateridae, Languriidae Leiodidae, Tenebrionidae, larvae and other Coleoptera) was the category with the highest frequency of prey items, found in 24 stomachs. The most important (IRI) groups amongst the prey of Z.pachyproctus were Coleoptera (24.52%) and followed by Orthoptera (24.43%), Blattodea (9.12%), Mantidae (8.14%) and Hemiptera (4.05%)., (Anh Van Pham, Gam Thi Trinh, Linh Hai Thi Dang, Duyen Thi Duong, Truong Quang Nguyen, Minh Duc Le, Thomas Ziegler.)

Background: Thanh Hoa Province is located in North Central Vietnam and the Province contains a large area of 393,361.33 hectares of natural forest. A complexity of landforms has given this Province a high level of biodiversity potential. However, the reptile fauna of Thanh Hoa Province is still underestimated. Previous studies documented 111 species of reptiles from this Province., New Information: As a result of our field surveys in Pu Luong and Xuan Lien Nature Reserves, we report five species of reptiles for the first time from Thanh Hoa Province, Vietnam, namely Plestiodontamdaoensis , Scincelladevorator (Scincidae), Elaphetaeniura , Pareasmacularius and Pseudoxenodonmacrops (Colubridae), with novel data about morphological characteristics. In addition, we provide an updated checklist of 116 species of reptiles from Thanh Hoa Province. The reptile fauna of Thanh Hoa Province also contains a number of species of conservation concern: 22 species listed in the Red Data Book of Vietnam, 22 species listed in the IUCN Red List, 18 species listed in the Vietnam Governmental Decree No. 84; and 21 species listed in CITES appendices., (Vinh Quang Dau, Thao Ngoc Hoang, Truong Quang Nguyen, Anh Van Pham.)

Background: Based on the examination of specimens of Amolopsminutus Orlov & Ho, 2007 and A.ottorum Pham, Sung, Pham, Le, Zieger & Nguyen, 2019, we found that there is no significant morphological difference between them. Phylogenetic analysis also showed that A.minutus and A.ottorum belong to the same taxon. In addition, we discovered the distribution of A.minutus in China., New Information: In this study, we provide the first molecular data of Amolopsminutus and regard A.ottorum as a junior synonym of A.minutus . In addition, we report the first record of A.minutus from China, based on nine specimens collected from Guanyinshan Provincial Nature Reserve in southern Yunnan Province and present an updated diagnosis of this species, based on literature data and newly-collected specimens., (Shuo Liu, Truong Quang Nguyen, Minh Duc Le, Cuong The Pham, Anh Van Pham, Mian Hou, Hongxin Zhou, Mingzhong Mo, Mei Li, Biao Li, Xiong Luo, Dingqi Rao, Song Li.)

The Sparreboom's Crocodile Newt ( Tylototritonsparreboomi ) is a recently discovered species of crocodile newts from Vietnam and it is currently known only from Sin Ho District in Lai Chau Province. Due to the limited information available on its population status and distribution, the species has been classified as Data Deficient in the IUCN Red List. As a result of our field surveys in 2021 and 2022 in north-western Vietnam, novel data on distribution and population status of and threats to this poorly-known species were collected. We combined the newly-discovered locations with previous occurrence records and used the data as input for modelling the potential distribution of the Sparreboom's Crocodile Newt. The results showed that the Sparreboom's Crocodile Newt's potential distribution encompasses areas in Lai Chau, Dien Bien and Son La Provinces, Vietnam, as well as a section in Jinping County, Yunnan Province, China. Based on the findings, we suggest that protected areas in the eastern side of Hoang Lien Mountain Range, such as Che Tao, Muong La, Hoang Lien - Van Ban and Bat Xat Nature Reserves and Hoang Lien National Park in Vietnam and Jinping Feishuling Nature Reserve in China be priority sites for the species conservation. Future research and conservation initiatives should prioritise efforts in such areas in an effort to find and protect new populations of the newt., Competing Interests: No conflict of interest to declare Disclaimer: This article is (co-)authored by any of the Editors-in-Chief, Managing Editors or their deputies in this journal., (Anh Van Pham, Minh Duc Le, Truong Quang Nguyen, Mai Huyen Le, Cuong The Pham, Anh Tuan Nguyen.)

The next generation of fusion reactors, exemplified by projects such as the Demonstration Power Plant following the International Thermonuclear Experimental Reactor, faces the monumental challenge of proving the viability of generating electricity through thermonuclear fusion. This pursuit introduces heightened complexities in diagnostic methodologies, particularly in microwave-based diagnostics. The increased neutron fluence necessitates significant reductions in vessel penetrations and the elimination of internal diagnostics, posing substantial challenges. SoC technology offers a promising solution by enabling the miniaturization, modularization, integration, and enhancing the reliability of microwave systems. After seven years of research, our team successfully pioneered the V- and W-band system-on-chip approach, leading to the development of active transmitters and passive receiver modules applied in practical settings, notably within the DIII-D tokamak project. Arrays of these modules have supported microwave imaging diagnostics. New physics measurement results from the Electron Cyclotron Emission Imaging system on DIII-D provide compelling evidence of improved diagnostics following the adoption of SoC technology. Furthermore, we achieved a breakthrough in developing an F-band SoC, advancing higher frequency capabilities for fusion devices. These achievements represent a significant leap forward in fusion diagnostic technology, marking substantial progress toward establishing reliable and efficient plasma diagnostics for future fusion reactors., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

At elevated temperatures, a strained, cyclic meta -quaterphenylene acetylene undergoes an intramolecular cyclization reaction to form benz[ e ]indeno[1,2,3- hi ]acephenanthrylene. This reaction represents an example of a Diels-Alder reaction at the 2-, 1-, 1'-, and 2'-positions of a biphenyl derivative, a region analogous to the bay regions of perylene and other periacenes. The reaction proceeds cleanly with high conversion. Kinetics studies of a methylated derivative reveal that the Δ G ‡ for the reaction is ∼40-41 kcal/mol, and computational models predict a similar value of G rel for the transition state of a concerted [4 + 2]-cycloaddition.

Background: Since the establishment of the Vu Quang National Park in 2002 in Ha Tinh Province, central Vietnam, several surveys on the amphibian fauna have been undertaken in this protected area. In 2009, Nguyen et al. provided a list of 23 amphibian species from Vu Quang National Park. In addition, a new species was described in 2021 from the National Park, namely Vietnamophrynevuquangensis ., New Information: As a result of our field surveys in 2013 and 2023, a total of 29 species of amphibians was recorded from the Vu Quang National Park. Six of them are recorded for the first time from Ha Tinh Province, comprising three species of Megophryidae, one species of Dicroglossidae, one species of Ranidae and one species of Rhacophoridae. In addition, we provide morphological data and ecological notes on the aforementioned species., (Vinh Quang Dau, Cuong The Pham, Truong Quang Nguyen, Toan Canh Thai, Anh Dinh Tran, Anh Van Pham.)

Introduction: Hepatocellular carcinoma (HCC) associated with concurrent portal vein tumour thrombus (PVTT) and bile duct tumour thrombus (BDTT) is sporadic and presents a puzzle to management with miserable prognostic., Case Presentation: The authors reported a case of HCC in the right liver with PVTT involving the right portal vein and BDTT developing in the common bile duct, detected in a 43-year-old man. The patient was admitted to our hospital with abdominal pain in the right hypochondrium and obstructive jaundice. Imaging studies showed a large mass in the right liver with invasion of the first branch of the portal vein and dilated intrahepatic bilateral bile ducts. A liver biopsy confirmed the diagnosis of hepatocellular carcinoma. Right hepatectomy plus thrombectomy en bloc with extrahepatic bile duct resection was performed. Subsequently, the patient received a postoperative adjuvant transarterial chemoembolization (PA-TACE) 1 month after surgery., Discussion: In the present case, the authors were not aiming for curative treatment by aggressive management but for palliative treatment. At the time of diagnosis, the tumour had already invaded the portal bifurcation. Hepatectomy plus thrombectomy en bloc with resection of common bile duct can remove biliary obstruction caused by BDTT, optimize portal flow by eliminating PVTT, and reduce the tumour burden, consequently improving the quality of life and liver function. Then, PA-TACE takes care of microfoci left behind by the surgery, which may prolong survival time., Conclusion: An aggressive therapeutic strategy should be considered in exceptional cases for resectable HCC with PVTT and obstructive BDTT. However, the follow-up period remains limited. A longer duration of observation is necessary to definitively assess the surgery's impact on patient's recurrence and survival time., Competing Interests: None.Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Background: Spinal epidural lipomatosis (SEL) is a rare contributor of low back pain (LBP) that can present with or without radicular symptoms., Case Presentation: A 51-year-old and 65-year-old male presented with chronic LBP to the Veterans Affairs chiropractic clinic for a trial of care. One had a moderate degree of lumbar spinal stenosis with known SEL and the other had severe. The patient with moderate grade stenosis responded favorably with weeks of transient benefit after visits and the patient with severe grade did not find benefit with care., Summary: SEL is a condition that conservative care providers should be aware of as a potential cause of central canal stenosis or neuroforaminal narrowing. Chiropractic management of SEL has been scarcely reflected in the published literature, but may be a viable option for transient symptom management., Competing Interests: The authors have no disclaimers, competing interests, or direct sources of support or funding to report in the preparation of this manuscript. The authors received indirect support from their institution in the form of computers and time spent preparing this manuscript. The involved patients provided consent for case publication. The VA Puget Sound Privacy Officer approved this submission., (© JCCA 2024.)

Objectives: Quality of surgery has recently become an essential topic in the prognosis of colon cancer. Complete mesocolic excision for colon cancer has recently gained popularity with high-quality surgery. Patient specimens after complete mesocolic excision with central vessel ligation procedures have an integrity of the mesocolon and the yield of three fields of lymph node harvest. We apply the glacial acid, absolute ethanol, water, and formaldehyde solution to each specimen based on the Japanese classification of lymph node groups and station numbers. We aim to identify the distribution and status of lymph node metastasis according to each tumor site and some pathological characteristics related to this disease., Methods: A prospective cohort study was performed on 45 laparoscopic complete mesocolic excision surgery patients., Results: 2791 lymph nodes were harvested after complete mesocolic excision surgery. The average number was 62.0 ± 22.3 nodes. The mean tumor size (in the largest dimension) was 4.2 ± 1.8 cm. The average length of the resected bowel segments was 29.1 ± 7.7 cm. There are 63 (2.3%) node metastases in 2791 lymph nodes, in which 17/45 (37.8%) patients had pN(+). The minimum positive node size was 1 mm. The positive pericolic lymph nodes (station 1) accounted for the highest rate, with 53 nodes (1.9%). The number of lymph nodes in young age ⩽60 is more significant than in older. The results were similar, with a more significant node retrieval in the group with a tumor size >4.5 cm and specimen length >25 cm. The number of lymph nodes in lower tumor invasive (pT1,3) was smaller than pT4. Our research shows that the cecum, ascending, and descending colon had greater nodes than others, with a mean number of 78.6, 74.2, and 71.3, respectively., Conclusions: The metastasis and harvested lymph nodes accounted for the highest rate of colon cancer in station 1 and the lowest rate in station 3. The number of retrieved lymph nodes was significantly associated with tumor location, size, specimen length, and patient age., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

Introduction and Importance: Synchronous primary cancers in the stomach and gallbladder were not previously reported in the medical literature. Pseudotumor pancreatitis was also described many years ago. It was misdiagnosed and required surgery for pancreatic head neoplasms., Presentation of Case: A 57-year-old male patient went to our hospital for abdominal pain. He was indicated for gastroduodenal endoscopy, and the result was adenocarcinoma. Abdominal ultrasound and Ctscan detected the gallbladder fundus's localized thickening structure and the pancreatic head's hyperechoic structure. The endoscopic ultrasound and MRI showed a gallbladder + pancreatic head tumor with chronic pancreatitis with pancreatic stones. The patient underwent distal gastrectomy, cholecystectomy, and pancreaticoduodenectomy., Clinical Discussion: The detection of gastric cancer is often based on upper gastrointestinal endoscopy and biopsy results. Gallbladder cancer is often diagnosed at an advanced stage, and only very few patients are diagnosed early. Pancreatic cancer often occurs in the head of the pancreas. Symptoms may include obstruction of the common bile and Wirsung duct, often in advanced stages. Surgery for the gallbladder, distal stomach, and head of pancreatic tumors are related to each other located in a neighboring location in the anatomy, so surgery to remove all three tumors is relatively similar to a pancreaticoduodenectomy procedure., Conclusion: Synchronous tumors of gastric carcinoma combined with gallbladder cancer and pseudotumor chronic pancreatitis are rare. The attitude of treating these three diseases at the same time requires a tumor board. Simultaneous surgery for gallbladder, stomach, and pancreatic head tumors can be performed if the tumors are still in the resectable stage., Competing Interests: Conflict of interest statement None declared. The authors have no financial, consultative, institutional, and other relationships that might lead to bias or conflict of interest., (Copyright © 2024. Published by Elsevier Ltd.)

Purpose: The main objectives were to test whether (1) a decrease in myelin is associated with enhanced rate of fibrillar tau accumulation and cognitive decline in Alzheimer's disease, and (2) whether apolipoprotein E (APOE) ε4 genotype is associated with worse myelin decrease and thus tau accumulation., Methods: To address our objectives, we repurposed florbetapir-PET as a marker of myelin in the white matter (WM) based on previous validation studies showing that beta-amyloid (Aβ) PET tracers bind to WM myelin. We assessed 43 Aβ-biomarker negative (Aβ-) cognitively normal participants and 108 Aβ+ participants within the AD spectrum with florbetapir-PET at baseline and longitudinal flortaucipir-PET as a measure of fibrillar tau (tau-PET) over ~ 2 years. In linear regression analyses, we tested florbetapir-PET in the whole WM and major fiber tracts as predictors of tau-PET accumulation in a priori defined regions of interest (ROIs) and fiber-tract projection areas. In mediation analyses we tested whether tau-PET accumulation mediates the effect of florbetapir-PET in the whole WM on cognition. Finally, we assessed the role of myelin alteration on the association between APOE and tau-PET accumulation., Results: Lower florbetapir-PET in the whole WM or at a given fiber tract was predictive of faster tau-PET accumulation in Braak stages or the connected grey matter areas in Aβ+ participants. Faster tau-PET accumulation in higher cortical brain areas mediated the association between a decrease in florbetapir-PET in the WM and a faster rate of decline in global cognition and episodic memory. APOE ε4 genotype was associated with a worse decrease in the whole WM florbetapir-PET and thus enhanced tau-PET accumulation., Conclusion: Myelin alterations are associated in an APOE ε4 dependent manner with faster tau progression and cognitive decline, and may therefore play a role in the etiology of AD., (© 2023. The Author(s).)

Morgagni hernia is a rare congenital diaphragmatic hernia associated with the minor retro-xiphoid region between the sternal and costal attachments. The bilateral and complicated Morgagni hernia occurred exceptionally rarely, at a rate of 4% and 6.5%. An 81-year-old woman with occasional constipation went to the emergency department for epigastric pain and vomiting 3 days before. She could no longer pass gas that caused abdominal distention. Clinical examination and ultrasound showed partial bowel obstruction, an unspecified cause. She received nil per os, nasogastric decompression. The abdominal and chest computed tomography Scan showed the bilateral diaphragmatic hernia, and the dilated loops of the cecum and ascending colon were 7 cm. She required an emergency operation to resolve the etiology of bowel obstruction. The midline incision was chosen to release the hernia contents and repair the posterior sternal defects with Polypropylene mesh. An abdominal approach can solve a bilateral incarcerated Morgagni hernia., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2023.)

Introduction: Early postoperative small bowel obstruction (EPSBO) is an obstruction that occurs within 4 weeks after the initial surgery. Routine prophylactic abdominal drainage does not provide any benefit in colon cancer surgery. The cause of EPSBO due to the abdominal drainage tube is infrequent., Case Presentation: A 72-year-old male patient was diagnosed with sigmoid carcinoma and underwent laparoscopic left colectomy. A surgical drain was placed in the pouch of Douglas through the incision of the right iliac fossa trocar site. On the fourth day, he began to flatus, and the abdominal pain decreased. However, on the ninth day after surgery, the patient had more abdominal pain, could not pass gas and defecate, and the abdomen was more distended. An abdominal computed tomography (CT) scan showed a dilated loop of the small intestine above the transition site with a drainage sonde and no dilation of the loop below the sonde. The patient was indicated to remove the sonde. He could pass gas and defecate the next day again and was relieved of the abdominal distention., Discussion: Once an EPSBO is considered, it is essential to think of the bowel obstruction caused by the drainage tube in the case of abdominal drainage. It is necessary to have a contrast CT scan to examine., Conclusion: EPSBO due to intra-abdominal drainage is a rare condition that presents a challenge in diagnosis and treatment. Diagnosis usually begins on the fourth postoperative day, mainly in operations in the lower transverse mesentery, including drainage placement after laparoscopic surgery., Competing Interests: The authors have no conflicts of interest to declare., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)

Background: The Hekou Torrent Frog ( Amolopsshihaitaoi ) was recently discovered from southern China and northern Vietnam in 2022. The knowledge about natural history and feeding ecology of this species is virtually lacking., New Information: Based on our recent fieldwork in northern Vietnam, we report a new population of A.shihaitaoi from Ha Giang Province. In this study, we provide novel data on the diet of A.shihaitaoi , based on stomach content analyses of 36 individuals (17 males and 19 females). A total of 36 prey categories with 529 items, comprising 515 items of invertebrates and 14 unidentified items, were found in the stomachs of A.shihaitaoi . The dominant prey items of the species were Hymenoptera (Formicidae), Orthoptera (Acrididae), Lepidoptera (Lepidoptera other), Mantodea (Mantidae) and Araneae. The importance index (Ix) of prey categories ranged from 7.1% to 11.5%. Hymenoptera (Formicidae) had the highest frequency of prey items, found in 36 stomachs., (Sonephet Siliyavong, Ngoc Van Hoang, Tao Thien Nguyen, Truong Nguyen, Anh Van Pham.)

Purpose of Review: Despite the increasing prevalence of autism spectrum disorder (ASD) among youth, disparities exist when it comes to access to diagnostic assessment and intervention of ASD in clinical and school settings. A review of the literature on sociocultural issues that contribute to these disparities would allow psychiatrists, clinicians, and researchers to better understand these challenges and aid in the development of culturally responsive approaches to support racially, ethnically, and linguistically diverse families of youth with ASD., Recent Findings: Disparities in ASD services are primarily due to system-level factors, including access to information or healthcare, stigma, and discrimination. Similarly, interactional factors, such as language/communication barriers, a lack of trust in professionals, and limited training in cultural responsiveness, can hinder support for diverse families of youth with ASD. This review focuses on several areas: (1) structural inequities that contribute to disparities in ASD services, (2) sociocultural issues in assessment and diagnosis, (3) sociocultural issues in interventions and service use, and (4) neurodiversity. This review underscores the importance of including diverse samples in ASD research to improve understanding of the strengths, challenges, perspectives, and preferences of underrepresented and underserved families of youth with ASD. These efforts can lead to culturally responsive service delivery., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Based on morphological and molecular analyses, we herein describe a new species of Achalinus from northern Vietnam. Achalinus quangi sp. nov. differs from its sister taxon, A. emilyae, and other members of the genus Achalinus by at least 4% in terms of genetic divergence based on fragments of the mitochondrial COI and Cytb genes and a combination of the following morphological characters: (1) maxillary teeth 27-29; (2) suture between the internasals distinctly longer than that between the prefrontals; (3) loreal not fused with prefrontal, extending from the nasal to the eye; (4) supralabials six; (5) infralabials five; (6) postocular absent, temporals 2+2, only the upper one in broad contact with eye; (7) dorsal scales in 25(23)-23-23(21) rows, keeled; (8) ventrals 139-141 in males, 141-154 in females; (9) subcaudals 75-84 in males, 69 in the female, all unpaired; (10) cloacal entire; (11) dorsum reddish brown to brown. Achalinus quangi sp. nov. consists of two subclades, the first one occurring on the northern side of the Da River in Son La and Tuyen Quang provinces and another subclade found on the southern side in Thanh Hoa, Nghe An, and Ha Tinh provinces. These two subclades are separated from each other by 1.8 to 2.3% genetic divergence and are slightly differing in ventral scalation.

A new species of small tree frog is described from northwestern Vietnam based on morphological differences and molecular divergence. Gracixalustruongi sp. nov. is distinguishable from its congeners and other small rhacophorid species on the basis of a combination of the following characters: size relatively small, SVL 32.2-33.1 mm in males, 37.6-39.3 mm in females; head slightly wider than long; vomerine teeth absent; snout round and long RL/SVL 0.17-0.19 in males, 0.16-0.17 in females; spines on upper eyelid absent; supratympanic fold distinct; tympanum distinct; dorsal skin smooth; throat smooth and venter granular; tibiotarsal projection absent; webbing of fingers rudimentary, toes with moderately developed webbing; dorsum moss-green, with an inverse Y-shaped dark green marking extended from interorbital region to posterior region of dorsum; external vocal sac absent in males; males with a nuptial pad on finger I. In the molecular analyses, the new species has no clear sister taxon and is at least 4.5% divergent from other congeners based on a fragment of the mitochondrial 16S rRNA gene., (Tung Thanh Tran, Anh Van Pham, Minh Duc Le, Nam Hai Nguyen, Thomas Ziegler, Cuong The Pham.)

Driven by host-pathogen coevolution, cell surface antigens are often the fastest evolving parts of a microbial pathogen. The persistent evolutionary impetus for novel antigen variants suggests the utility of novelty-seeking algorithms in predicting antigen diversification in microbial pathogens. In contrast to traditional genetic algorithms maximizing variant fitness, novelty-seeking algorithms optimize variant novelty. Here, we designed and implemented three evolutionary algorithms (fitness-seeking, novelty-seeking, and hybrid) and evaluated their performances in 10 simulated and 2 empirically derived antigen fitness landscapes. The hybrid walks combining fitness- and novelty-seeking strategies overcame the limitations of each algorithm alone, and consistently reached global fitness peaks. Thus, hybrid walks provide a model for microbial pathogens escaping host immunity without compromising variant fitness. Biological processes facilitating novelty-seeking evolution in natural pathogen populations include hypermutability, recombination, wide dispersal, and immune-compromised hosts. The high efficiency of the hybrid algorithm improves the evolutionary predictability of novel antigen variants. We propose the design of escape-proof vaccines based on high-fitness variants covering a majority of the basins of attraction on the fitness landscape representing all potential variants of a microbial antigen.

Early identification of executive dysfunction and timely school-based intervention efforts are critical for students at risk for problematic behaviors during early elementary school. The original Behavior Rating Inventory of Executive Functioning (BRIEF) was designed to measure real-world behavioral manifestations of executive functioning, neurocognitive processes critical for school success. With the updated BRIEF-2, independent validation is needed with kindergarten and first grade students at risk for emotional and behavioral disorders. Thus, using item level analyses, we examined the factor structure of the BRIEF-2 Teacher Rating form with 1,112 students. Results indicated little evidence for the original three-index model and supported a modified two-index model, with a Cognitive Regulation Index and an overall Behavior-Emotion Regulation Index. Criterion related validity indicated positive relationships with performance-based executive functioning (Head-Toes-Knees-Shoulders) and later internalizing and externalizing behaviors. We discuss implications of findings for early identification and school-based intervention efforts, as well as future research.

Accurate human identification using radar has a variety of potential applications, such as surveillance, access control and security checkpoints. Nevertheless, radar-based human identification has been limited to a few motion-based biometrics that are solely reliant on micro-Doppler signatures. This paper proposes for the first time the use of combined radar-based heart sound and gait signals as biometrics for human identification. The proposed methodology starts by converting the extracted biometric signatures collected from 18 subjects to images, and then an image augmentation technique is applied and the deep transfer learning is used to classify each subject. A validation accuracy of 58.7% and 96% is reported for the heart sound and gait biometrics, respectively. Next, the identification results of the two biometrics are combined using the joint probability mass function (PMF) method to report a 98% identification accuracy. To the best of our knowledge, this is the highest reported in the literature to date. Lastly, the trained networks are tested in an actual scenario while being used in an office access control platform to identify different human subjects. We report an accuracy of 76.25%.

We employ a 77-81 GHz frequency-modulated continuous-wave (FMCW) millimeter-wave radar to sense anomalous vibrations during vehicle transport at highway speeds for the first time. Secure metallic containers can be breached during transport by means of drilling into their sidewalls but detecting a drilling signature is difficult because the large vibrations of transport drown out the small vibrations of drilling. For the first time, we demonstrate that it is possible to use a non-contact millimeter-wave radar sensor to detect this micron-scale intrusive drilling while highway-speed vehicle movement shakes the container. With the millimeter-wave radar monitoring the microdoppler signature of the container's vibrating walls, we create a novel signal-processing pipeline consisting of range-angle tracking, time-frequency analysis, horizontal stripe image convolution, and principal component analysis to create a robust and powerful detection statistic to alarm if drilling is present. To support this pipeline, we develop a statistical model combining the vibrating container and the random vibrations induced by vehicle movement to explore the robustness of the sensor's detection capabilities. The presented results strongly support the inclusion of a millimeter-wave radar vibration sensor into a transport security system.

This paper presents the design and development of miniature coils for wireless power and data transfer through metal. Our coil has a total size of 15 mm × 13 mm × 6 mm. Experimental results demonstrate that we can harvest 440 mW through a 1 mm-thick aluminum plate. Aluminum and stainless-steel barriers of different thicknesses were used to characterize coil performance. Using a pair of the designed coils, we have developed a through-metal communication system to successfully transfer data through a 1 mm-thick aluminum plate. A maximum data rate of 100 bps was achieved using only harvested power. To the best of our knowledge, this is the first report that demonstrates power and data transfer through aluminum using miniature coils.

We use state-level data to evaluate the connection between outbreaks of COVID-19 and stock returns over the period January-June 2020. We show that daily increases in the number of infected cases, hospitalized cases, and deaths are negatively associated with next day stock returns of firms headquartered in the same state. The relationship is weaker among states with high levels of medical resources and states that are likely to get support from the federal government. In addition, we find that the negative effect is reduced for firms that report an expectation that an outbreak will increase revenues and for firms with a strong corporate social responsibility practice. We believe our study is the first paper to assess cross-sectional stock price reactions to COVID-19 as a function of the state-level impact of the pandemic outbreak., Competing Interests: None., (© 2021 Elsevier Inc. All rights reserved.)

This Letter describes a super-oscillatory lens (SOL), with concentric ring-type metallic slits photolithographically fabricated on a glass substrate, that can function at subterahertz frequencies. The SOL has been investigated both experimentally and theoretically and demonstrates a spatial resolution of 1.5 mm (0.5 λ ), which is 0.45 times the diffraction limit, with a focal length of 75 mm (25 λ ) at 100 GHz ( λ =3 m m ). Furthermore, the depth of focus of the lens was measured to be 47 mm, which is 10.8 times larger than that of a conventional lens. This type of SOL, with subdiffraction focusing, is thus highly effective for use in industrial inspections with millimeter and terahertz waves.

Paragangliomas are uncommon neuroendocrine neoplasms that occur in characteristic locations. While parasympathetic paragangliomas are mainly located at the head and neck, sympathetic paragangliomas are mostly located below the neck. Among parasympathetic paragangliomas, pheochromocytomas are the most common. Ninety percent of cases of pheochromocytomas arise within the adrenal gland. We report a case of a 63-year-old woman with an extra-adrenal pheochromocytoma of the organ of Zuckerkandl detected by CT and MRI and subsequently confirmed by postoperative histology and immunohistochemistry., (© 2020 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)

Retroperitoneal gastrointestinal tumor is the rarest subtype among 3 subtypes of extragastrointestinal tumors, which are uncommon stromal tumors. We herein report a case of a 55-year-old man with retroperitoneal gastrointestinal tumor detected by magnetic resonance imaging and confirmed by postoperative histology and immunohistochemistry., (© 2020 The Authors. Published by Elsevier Inc. on behalf of University of Washington.)

Background: Son La Province is located in north-western Vietnam and the province contains a large area of 440,000 hectares of natural forest. A wide range of elevations and the complexity of landforms have given this province a great diversity of natural habitats and a high level of biodiversity potential. However, the snake fauna of Son La province is still poorly studied. Previous studies documented 56 species of snakes from this province., New Information: As a result of our field surveys in Phu Yen, Song Ma, Thuan Chau and Van Ho districts, we report five species of snakes for the first time from Son La Province, northern Vietnam, namely Boiga cyanea, B. guangxiensis , Lycodon meridionalis (Colubridae), Protobothrops cornutus and P. mucrosquamatus (Viperidae), with novel data about morphological characters. In addition, we provide an updated checklist of 61 snake species from Son La Province. The snake fauna of Son La Province also contains a number of species of conservation concern: 11 species listed in the Red Data Book of Vietnam (2007), four species listed in the IUCN Red List (2020) and four species listed in the Vietnam Governmental Decree No. 06 (2019)., (Anh Van Pham, Thomas Ziegler, Truong Quang Nguyen.)

The Tylototriton asperrimus complex from northern Vietnam is reviewed based on morphological comparisons and analysis of the mitochondrial marker NADH dehydrogenase subunit 2 (ND2). Based on molecular divergences, which were revealed to be higher than in other congeners, in concert with morphological differences, two new species and one subspecies are described herein: Tylototriton pasmansi sp. nov. differs from T. asperrimus sensu stricto by 3.2 to 3.6 % genetic divergence and a combination of distinct morphological characters, such as head slightly longer than wide, distinct mid-dorsal ridge, relatively wide distance between the eyes, tips of fingers reaching the eye when foreleg is laid forward, labial and gular folds present, central belly skin with tubercles shaped like transverse wrinkles and distinct, pointy to round rib nodules. The population of T. pasmansi sp. nov. consists of two subclades, the nominotypic one occurring on the eastern side of the Da River (or Black River, including Hoa Binh and Phu Tho provinces), and another occurring on the western side (including Son La and Thanh Hoa provinces). These two subclades differ by 2.5 to 3.1 % genetic divergence and distinct morphological characters. The western subclade is herein described as Tylototriton pasmansi obsti ssp. nov. , which differs from the nominotypic form by a wider head, longer and narrower snout, shorter femur length, and an overall less granulose skin, without an increased concentration of warts on the body sides. A second new species, Tylototriton sparreboomi sp. nov. is described from Lai Chau Province. It differs from T. asperrimus sensu stricto by 4.1 to 4.2 % and from Tylototriton pasmansi sp. nov. by 3.6 to 4.5 % genetic divergences as well as by a combination of distinct morphological characters, such as head longer than wide, tips of fingers reaching nostril when foreleg adpressed along head, rib nodules distinct, round and relatively enlarged, and wide distance between the eyes., (Marta Bernardes, Minh Duc Le, Truong Quang Nguyen, Cuong The Pham, Anh Van Pham, Tao Thien Nguyen, Dennis Rödder, Michael Bonkowski, Thomas Ziegler.)

Purpose of Review: Limited work has emphasized cultural responsiveness when working with families and children with attention-deficit/hyperactivity disorder (ADHD) from diverse backgrounds. We present a primer for psychiatrists, psychologists, and other mental health professionals on the implementation of culturally responsive practices within a multi-tiered system of support (MTSS) framework when collaborating with schools., Recent Findings: Individuals with ADHD demonstrate unique behavioral challenges that affect school and home functioning. As a framework to address the needs of all children with academic and behavioral issues, many public schools have adopted MTSS. Emerging findings on cultural adaptations of evidence-based interventions for ADHD within MTSS are promising. Through a comprehensive tiered approach, this review focuses on (1) initial behavior screening and prevention, (2) implementation of evidence-based interventions tailored to the child's development and family culture, and (3) collaboration between psychiatrists, psychologists, school personnel, and families regarding evaluation of outcomes for children with ADHD, particularly when pharmacological treatment is considered. Engaging in these approaches can promote culturally responsive practices and improve the quality of services provided to children with ADHD.

Introduction: Anorectal malignant melanoma is an uncommon and highly malignant disease with a greater incidence in females. Many patients were misdiagnosed as hemorrhoids, benign polyps, and rectal cancer. They were often diagnosed in an advanced stage. Wide local excision and abdominoperineal resection are the main treatments of rectal melanoma., Presentation of Case: A case report is a 77-year-old man who has blood in the stool for 4 months without clinical examination. He admitted to the emergency room with sudden syndromes that related to bowel perforation. Rectal examination detected a large anorectal polyp. Computer tomography showed free air and fluid in the peritoneal cavity. He was received laparoscopic surgery and found the fishbone penetrated the sigmoid colon without polyp resection. The polyp was treated by local excision a few days later. The histology examination was a primary malignant melanoma. Due to the pigmented lesion that remained from the resected polyp's root, the abdominoperineal resection was performed as a radical treatment., Discussion: Diagnosis of anorectal malignant melanoma is difficult because of atypical signs, that are confused with bleeding hemorrhoids especially an amelanotic melanoma. Treatment is controversial, including surgery, radiotherapy, chemotherapy, and target therapy. A present case is an option in radical surgery., Conclusion: Anorectal melanoma is a rare disease with poor results and prognosis. A lack of large-data leads to a missing evidence-based guideline in this disease. Early-staging diagnosis and surgical treatment help patients improve their overall survival., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: The family Megophryidae is one of the most poorly known groups of amphibians in Son La Province, Vietnam. In the herpetofaunal list of Vietnam in 2009 only two species of megophryids were recorded from this province and recent studies have documented five additional species of Megophryidae from Son La Province., New Information: Based on recent field work in northern Vietnam, we report six new provincial records of the family Megophryidae from Son La Province, namely Leptobrachium ailaonicum , Leptobrachella sungi , Megophrys feae , M. jingdongensis , M. microstoma and M. parva . In addition, morphological data were provided for each species, based on newly collected specimens. Our findings bring the species number of the family Megophryidae to 13 in Son La Province., (Anh Van Pham, Cuong The Pham, Lan Duc Doan, Thomas Ziegler, Truong Quang Nguyen.)

Three new species of the xenodermatid genus Achalinus are described from northern Vietnam based on morphological and molecular evidence: Achalinus juliani sp. nov. is characterized by a combination of the following characters: 1) maxillary teeth 28; 2) suture between the internasals distinctly longer than that between the prefrontals; 3) internasal not fused to prefrontal; 4) loreal not fused with prefrontal; 5) infralabials 6; 6) mental separated from anterior chin shields; 7) two elongated anterior temporals, in contact with the eye, and two posterior temporals; 8) dorsal scales in 25-23-23 rows, keeled; 9) ventrals 173-179; 10) subcaudals 77-91, unpaired; 11) a total length of at least 413 mm (with a maximum tail length of 109 mm, and a tail/total length ratio of 0.22-0.37); 12) dorsum in preservative reddish to greyish brown above, with the lower and posterior head sides being paler; venter greyish cream, with the underside of the tail being somewhat darker. Achalinus timi sp. nov. is characterized by a combination of the following characters: 1) maxillary teeth 27; 2) suture between the internasals distinctly longer than that between the prefrontals; 3) loreal fused with the prefrontal on each side, with the prefrontal extending towards the supralabials; 4) dorsal scales in 25-25-23 rows, keeled; 5) ventrals 170+1; 6) subcaudals 72, unpaired; 7) a total length of at least 177.9 mm in males (with a tail length of 37.9 mm, and a tail/total length ratio of 0.21); 8) dorsum in preservative reddish to greyish brown above, with wide portion of the vertebral region being distinctly darker; the lower head sides somewhat paler; infralabial and chin shields light greyish brown; venter greyish cream, with the underside of the tail being somewhat darker and the chin region somewhat paler. Achalinus emilyae sp. nov. is characterized by a combination of the following characters: 1) maxillary teeth 27 or 28; 2) suture between internasals distinctly longer than that between the prefrontals; 3) internasal not fused to prefrontal; 4) loreal not fused with prefrontal; 5) infralabials 5; 6) mental separated from anterior chin shields; 7) two anterior temporals, only the upper one in contact with eye, and two posterior temporals; 8) dorsal scales in 23-23-23 rows, keeled; 9) ventrals in females 157-161; 10) subcaudals in females 63, unpaired; 11) a total length of at least 519.5 mm (with a maximum tail length of 95.1 mm, and a tail/total length ratio of 0.18 in females); 12) dorsum iridescent pale yellowish brown with a dark longitudinal mid-dorsal stripe. In terms of pairwise genetic distance (cytochrome c oxidase subunit 1, COI), the three new species differ by at least 12.7% from other members of the genus, including themselves. The total number of Achalinus known is increased to twelve and the number of Achalinus species known from Vietnam is increased from three to six. Currently ten species of xenodermatids are known to exist in Vietnam: Achalinus ater, A. emilyae, A. juliani, A. rufescens, A. spinalis, A. timi, Fimbrios klossi, F. smithi, Parafimbrios lao, and P. vietnamensis.