Duplicated paralog of sulfide: quinone oxidoreductase contributes to the adaptation to hydrogen sulfide-rich environment in the hydrothermal vent crab, Xenograpsus testudinatus.

The hydrothermal crab, Xenograpsus testudinatus (xtcrab) inhabits shallow-water, hydrogen sulfide (H2S)-rich hydrothermal vent regions. Until now, the adaptative strategy of xtcrab to this toxic environment was unknown. Herein, we investigated the sulfide tolerance and detoxification mechanisms of xtcrabs collected in their high-sulfide hydrothermal vent habitat. Experimental immersion of xtcrab in various sulfide concentrations in the field or in aquaria assessed its high sulfide tolerance. HPLC measurement of hemolymph sulfur compounds highlighted xtcrab detoxification capacity via catabolism of sulfide into much less toxic thiosulfate. We focused on a key enzyme for H2S detoxification, sulfide: quinone oxidoreductase (SQR). Cloning and phylogenetic analysis revealed two SQR paralogs in xtcrab, that we named xtSQR1 and xtSQR2. As shown by qPCR, xtSQR2 and xtSQR1 were expressed in the digestive gland, suggesting the involvement of both paralogs in the detoxification of food-related H2S. In contrast, xtSQR1 transcript was highly expressed in the gill, while xtSQR2 was not detectable, suggesting a specific role of SQR1 in gill detoxification of H2S of environmental origin. Comparison between xtcrabs in their hydrogen sulfide-rich hydrothermal habitat, and xtcrabs maintained for one month in sulfide-free seawater aquarium, showed higher transcript levels of gill xtSQR1 in sulfide-rich habitat, further supporting the specific role of xtSQR1 paralog in environmental H2S detoxification in the gill. Gill SQR protein level as measured by Western blot, and gill SQR enzyme activity were also higher in sulfide-rich habitat. Immunohistochemical staining further showed that SQR expression was co-localized with Na+/K+-ATPase-positive epithelial and pillar cells of the gill filament. This is the first evidence of duplicate SQR genes in crustaceans. Overall, our study suggests that the subfunctionalization of duplicate xtSQR genes may play an important role in sulfide detoxification to maintain the sulfide homeostasis in X. testudinatus, providing an ecophysiological basis for its adaptation to the high-sulfide hydrothermal vent environment.

Influence of shift work on rest-activity rhythms, sleep quality, and fatigue of female nurses.

Female nurses working rotating shifts must change their daily routines often, which affects their biological circadian rhythms and could cause sleep disorders and fatigue. The objective of this study was to compare the sleep-wake rhythms, sleep quality, and fatigue of female nurses working rotating shifts and fixed day shifts and to analyze the factors that influence their fatigue. Participants comprised a shift worker group of 101 nurses and a day worker group of 76 nurses. Following the collection of basic information of the nurses and their scores in the various constructs of the Pittsburg Sleep Quality Index (PSQI) and the Checklist Individual Strength (CIS) questionnaire, each nurse wore an actigraph for seven consecutive days to collect for analysis the sleep-wake rhythm parameter dichotomy index (I < O) and durations of continuous sleep and wake. Multivariable linear regression was then used to determine whether the influence of various variables on fatigue differed between the two groups. Results revealed that the sleep-wake rhythm parameter I < O of the day worker group was significantly higher than that of the shift worker group (t = 5.08, p < .001). The shift worker group exhibited significantly higher PSQI global scores (t = -2.00, p = .047), longer total sleep time (t = 2.07, p = .040), poorer habitual sleep efficiency (t = -3.06, p = .003), and greater use of sleeping medication (t = -2.90, p = .004) than did the day worker group. Multivariable linear regression was performed to analyze the important predictors of the CIS score in the two groups with body mass index, age, work experience, marital status, educational background, department of employment, shift type at the time of recruitment, sleep-wake rhythm parameter I < O, and quality of sleep as independent variables. Results indicated that in the shift worker group, the overall explanatory power (R2) of the multivariable linear regression model was 22.9% (F = 3.01, p = .003), and only the PSQI global score (ß = 0.33, p = .003) influenced the CIS score. In the day worker group, the various variables did not influence the CIS score in the multivariable linear regression model. Although the female nurses working rotating shifts spent more time in bed, their sleep-wake rhythms and sleep quality were poorer than those of the day worker group. Furthermore, the sleep quality of female nurses in the shift worker group had a significant impact on their fatigue. In other words, for female nurses who must work rotating shifts, sleep quality determines whether fatigue can be reduced. The shift-working nurses themselves should implement sleep management, such as avoiding disruptions to their sleep-wake rhythm and improving sleep quality, which should be effective strategies to reduce fatigue.

Bacterial Dynamics in the Accessory Nidamental Gland of Sepioteuthis lessoniana throughout Maturation.

The accessory nidamental gland (ANG) is part of the reproduction organ in the majority of female cephalopods, including the bigfin reef squid Sepioteuthis lessoniana, an economically important fishery product. Microbes in Alphaproteobacteria, Gammaproteobacteria, and Verrucomicrobia have been suggested to play a role in the maturation of the S. lessoniana ANG and are responsible for its color. However, the bacterial composition and dynamics of the different maturation stages of the ANG remain unclear. In the present study, we surveyed ANG-associated bacterial dynamics in wild-caught S. lessoniana at various developmental stages in different populations over 3 years. The results obtained showed that the ANG bacterial community shifted gradually and decreased in diversity throughout maturation. Verrucomicrobia occupied the ANG during the early stages in large numbers, and was replaced by Bacteroidia, Alphaproteobacteria, and Gammaproteobacteria in the later stages. Flavobacteriales and Alphaproteobacteria both appeared to contribute to pigmentation, while Bacteroidia, Alphaproteobacteria, and Gammaproteobacteria may be involved in enriching the heme biosynthesis pathway in the ANG with the maturation of S. lessoniana. The present results provide an open question of whether S. lessoniana actively selects the bacterial community in the ANG to adjust to its surrounding environment.

Complex History of Aerobic Respiration and Phototrophy in the Chloroflexota Class Anaerolineae Revealed by High-Quality Draft Genome of Ca. Roseilinea mizusawaensis AA3_104.

Roseilinea is a novel lineage of Chloroflexota known only from incomplete metagenome-assembled genomes (MAGs) and preliminary enrichments. Roseilinea is notable for appearing capable of anoxygenic photoheterotrophy despite being only distantly related to well-known phototrophs in the Chloroflexia class such as Chloroflexus and Roseiflexus. Here, we present a high-quality MAG of a member of Roseilinea, improving our understanding of the metabolic capacity and phylogeny of this genus, and resolving the multiple instances of horizontal gene transfer that have led to its metabolic potential. These data allow us to propose a candidate family for these organisms, Roseilineaceae, within the Anaerolineae class.

The Characteristics and Expression Profile of Transferrin in the Accessory Nidamental Gland of the Bigfin Reef Squid during Bacteria Transmission.

The accessory nidamental gland (ANG) is a female reproductive organ found in most squid and cuttlefish that contains a consortium of bacteria. These symbiotic bacteria are transmitted from the marine environment and selected by the host through an unknown mechanism. In animals, a common antimicrobial mechanism of innate immunity is iron sequestration, which is based on the development of transferrin (TF)-like proteins. To understand this mechanism of host-microbe interaction, we attempted to characterize the role of transferrin in bigfin reef squid (Sepioteuthis lessoniana) during bacterial transmission. qPCR analysis showed that Tf was exclusively expressed in the outer layer of ANG,and this was confirmed by in situ hybridization, which showed that Tf was localized in the outer epithelial cell layer of the ANG. Western blot analysis indicated that TF is a soluble glycoprotein. Immunohistochemical staining also showed that TF is localized in the outer epithelial cell layer of the ANG and that it is mainly expressed in the outer layer during ANG growth. These results suggest that robust Tf mRNA and TF protein expression in the outer layer of the ANG plays an important role in microbe selection by the host during bacterial transmission.

Differences in workday sleep fragmentation, rest-activity cycle, sleep quality, and activity level among nurses working different shifts.

Schedule changes associated with rotating shifts can interfere with the circadian rhythms of nurses and thereby affect their sleep duration, sleep quality, work efficiency, and work performance. The objectives of this study was to investigate differences in workday sleep fragmentation, rest-activity cycle, sleep quality, and activity level among nurses working different shifts. After filling out a basic information questionnaire and completing the Pittsburgh Sleep Quality Index (PSQI) questionnaire, participants were asked to wear an actigraph and keep sleep records for seven consecutive days. Data pertaining to wake after sleep onset (WASO), 24-hour autocorrelation coefficient (r24), and daytime activity mean was collected in order to investigate workday sleep fragmentation, rest-activity cycle, and daytime activity level. We obtained complete questionnaires and data from 191 nurses. Day- and evening-shift nurses had more regular workday rest-activity cycles than did night-shift nurses (F = 51.26, p < .001). After controlling for r24 coefficients, we determined that nurses who experienced greater workday sleep fragmentation had higher PSQI scores (ß = .18, p = .008). After controlling for WASO times, we determined that nurses who had more regular rest-activity cycles on workdays had lower PSQI scores (ß = - .16, p = .036). After controlling for shift type and WASO times, we determined that nurses with higher PSQI scores displayed lower activity levels (ß = - .21, p = .015) and those with higher r24 coefficients displayed higher activity levels (ß = .18, p = .040) on workdays. We then examined the causal path relationships. Among the shifts, only the day-shift nurses had a higher r24 (ß = -.59, p < .001) than did the night-shift nurses; WASO exerted a significant impact on PSQI scores (ß = .20, p = .002); r24 had a significant and negative influence on PSQI scores (ß = -.38, p < .001), and PSQI scores significantly and negatively influenced workday activity levels (ß = -.20, p = .006). This study determined that day- and evening-shift nurses enjoyed more regular and consistent rest-activity cycles than did night-shift nurses; nurses with greater workday sleep fragmentation and/or more irregular rest-activity cycles experienced poorer sleep quality; and nurses suffering from poorer sleep quality displayed lower daytime activity levels on workdays.

The germline-specific expression of Foxl3a and its paralogous Foxl3b are associated with male gonadal differentiation in the Japanese eel, Anguilla japonica.

Unlike its paralog Foxl2, which is well known for its role in ovarian development in vertebrates, the function of Foxl3 is still unclear. Foxl3 is an ancient duplicated copy of Foxl2. It is present as a single copy in ray-finned fish. But, due to repeated losses, it is absent in most tetrapods. Our transcriptomic data, however, show that two Foxl3s (Foxl3a and its paralog Foxl3b) are present in Japanese eel. Foxl3a is predominantly expressed in the pituitary, and Foxl3b is predominantly expressed in the gills. Both Foxl3s show a sex-dimorphic expression, being higher expression in testes than in ovaries. Moreover, Foxl3a and Foxl3b were exclusively expressed during gonadal differentiation in control eels (100% male). Conversely, Foxl3a and Foxl3b significantly decreased after gonadal differentiation in E2-treated eels (100% female). Furthermore, in accordance the difference in adhesive ability between somatic cells and germline cells in testes, Foxl3s showed a high expression in suspension cells (putative germline cells) and low expression in adhesive cells (putative somatic cells). In situ hybridization further showed that Foxl3a and Foxl3b were expressed in the testicular germline cells. In addition, Foxl3s expression was not changed by sex steroids in in vitro testes culture. Taken together, our results suggest that the teleost-specific Foxl3 paralog was repeatedly lost in most fish after the third round of whole genome duplication. The two germline-expressed Foxl3s had higher expression levels in males than in females during gonadal differentiation in Japanese eel. These results demonstrated that Foxl3s might play an important role in germline sexual fate determination from ancient fish to modern fish.

Two distinct vitellogenin genes are similar in function and expression in the bigfin reef squid Sepioteuthis lessoniana.

Unlike vitellogenin, which is the sole major precursor of yolk protein in all oviparous vertebrates, a variety of major precursor of yolk proteins are found among oviparous invertebrates. Sea urchins have a transferrin-like yolk protein, while all other major precursors of yolk proteins in oviparous invertebrates belong to the superfamily of large lipid transfer proteins (LLTPs). However, a comprehensive understanding of vitellogenesis is absent in cephalopods. To understand control of vitellogenesis by the LLTPs gene, two vitellogenins (VTG1 and VTG2), two apolipophorins (APOLP2A and APOLP2B), and a cytosolic large subunit of microsomal triglyceride transfer protein (MTTP) found in the bigfin reef squid. Only the two VTGs showed high levels of expression in mature females compared to males. We further analyzed the expression profile and localization of both VTGs/VTGs during ovarian development. Our data showed that VTGs/VTGs expressions were correlated to the female reproductive cycle. Ovarian VTG1 and VTG2 were localized in the follicle cells but not in oocytes. In addition, VTG1 and VTG2 were represented in follicle cells and oocytes. Thus, our results showed that both VTGs were synthesized by follicle cells and are then delivered to oocytes. In addition, we demonstrated that VTGs were the major precursor of yolk protein in bigfin reef squid. We also found differential proteolytic cleavage processes of VTG1 and VTG2 during VTGs accumulation in oocytes. Therefore, our data shed light on the molecular mechanism of the yolk accumulation pathway in cephalopods.

Robust gdf9 and bmp15 expression in the oocytes of ovotestes through the Figla-independent pathway in the hermaphroditic black porgy, Acanthopagrus schlegelii.

More than 1,500 fish species are hermaphroditic, but no hermaphroditic lineage appears to be evolutionarily ancient in fishes. Thus, whether more than one sex at a time was present during the evolutionary shift from gonochorism to hermaphroditism in fishes is an intriguing question. Ectopic oocytes were created in the ovotestes of protandrous black porgy via the withdrawal of estradiol (E2) administration. These ectopic oocytes reprogrammed the surrounding cells, which changed from Sertoli cells to follicle-like cells. We observed that gdf9 and bmp15 expression was localized in the primary oocytes and gradually decreased after oocytes entered a secondary oocyte stage. Robust expression of gdf9 and bmp15 in ectopic oocytes was associated with the surrounding Sertoli cells. However, blocking Cyp19a1a activity and increasing androgen levels did not stimulate the expression of gdf9 and bmp15. Thus, the robust gdf9 and bmp15 expression was not related to the inappropriate male microenvironment. Furthermore, in vitro data demonstrated that gdf9 and bmp15 were not downstream genes of Figla signaling. Therefore, our results suggest that there are two independent mechanisms, a Figla-dependent pathway and a Figla-independent pathway, by which oocyte-surrounding cells are altered from a male somatic fate to a female somatic fate. This functional switch might clarify how oocytes created an appropriate microenvironment during the transition from the ancient gonochorism to the present hermaphroditism.

Expression profile of amh/Amh during bi-directional sex change in the protogynous orange-spotted grouper Epinephelus coioides.

Gonadal differentiation is tightly regulated by the initial sex determining gene and the downstream sex-related genes in vertebrates. However, sex change in fish can alter the sexual fate from one sex to the other. Chemical-induced maleness in the protogynous orange-spotted grouper is transient, and a reversible sex change occurs after the chemical treatment is withdrawn. We used these characteristics to study Amh signaling during bi-directional sex change in the grouper. We successfully induced the female-to-male sex change by chemical (aromatase inhibitor, AI, or methyltestosterone, MT) treatment. A dormant gonad (a low proliferation rate of early germ cells and no characteristics of both sexes) was found during the transient phase of reversible male-to-female sex change after the withdrawal of chemical administration. Our results showed that amh (anti-mullerian hormone) and its receptor amhr2 (anti-mullerian hormone receptor type 2) were significantly increased in the gonads during the process of female-to-male sex change. Amh is expressed in the Sertoli cells surrounding the type A spermatogonia in the female-to-male grouper. Male-related gene (dmrt1 and sox9) expression was immediately decreased in MT-terminated males during the reversible male-to-female sex change. However, Amh expression was found in the surrounding cells of type A spermatogonia-like cells during the transient phase of reversible male-to-female sex change. This phenomenon is correlated with the dormancy of type A spermatogonia-like cells. Thus, Amh signaling is suggested to play roles in regulating male differentiation during the female-to-male sex change and in inhibiting type-A spermatogonia-like cell proliferation/differentiation during the reversible male-to-female sex change. We suggest that Amh signaling might play dual roles during bi-directional sex change in grouper.

The Testis Is a Primary Factor That Contributes to Epigenetic Modifications in the Ovaries of the Protandrous Black Porgy, Acanthopagrus schlegelii.

In most hermaphroditic fish, the sexual phase of the gonad responds to external stimuli so that only one sex remains functional while the other sex becomes dormant. However, protandrous black porgy are male during their first two reproductive cycles. Estradiol (E2)-induced female growth results in a transient and immature female, and the sexual phase reverts from female to male after E2 is withdrawn. Conversely, excising the testis results in a precocious female when performed during the second reproductive cycle. We used these characteristics to study epigenetic modifications of cyp19a1a promoter in black porgy. Our results showed that higher levels of gonadotropins receptors were observed in testis than in ovary during the alteration of sexual phase from induced femaleness to maleness, and hCG treatment did not stimulate ovarian gene expression in male (1-yr-old maleness) and female phase (testis excision-induced femaleness) fish. The cyp19a1a promoter exhibited tissue- and lineage-specific methylation patterns. The follicle cells in the ovary had a hypomethylated (0%-20%) cyp19a1a promoter region. In the ovary, the first sign of female phase decision was decreased methylation levels and increased numbers of hypomethylated clones of cyp19a1a promoter during the natural sex change process. Similar methylation patterns were observed in the testis-removed ovary 1 mo after surgery, with no histological difference between the sham and the testis-removed fish. Conversely, there was no increase in methylation levels of cyp19a1a promoter in E2-fed fish. These results suggest that in the digonic gonad of black porgy, the testis is the primary tissue that affects epigenetics of the ovary.

Sexual Fate Reprogramming in the Steroid-Induced Bi-Directional Sex Change in the Protogynous Orange-Spotted Grouper, Epinephelus coioides.

Androgen administration has been widely used for masculinization in fish. The mechanism of the sex change in sexual fate regulation is not clear. Oral administration or pellet implantation was applied. We orally applied an aromatase inhibitor (AI, to decrease estrogen levels) and 17α-methyltestosterone (MT, to increase androgen levels) to induce masculinization to clarify the mechanism of the sex change in the protogynous orange-spotted grouper. After 3 mo of AI/MT administration, male characteristics were observed in the female-to-male sex change fish. These male characteristics included increased plasma 11-ketotestosterone (11-KT), decreased estradiol (E2) levels, increased male-related gene (dmrt1, sox9, and cyp11b2) expression, and decreased female-related gene (figla, foxl2, and cyp19a1a) expression. However, the reduced male characteristics and male-to-female sex change occurred after AI/MT-termination in the AI- and MT-induced maleness. Furthermore, the MT-induced oocyte-depleted follicle cells (from MT-implantation) had increased proliferating activity, and the sexual fate in a portion of female gonadal soma cells was altered to male function during the female-to-male sex change. In contrast, the gonadal soma cells were not proliferative during the early process of the male-to-female sex change. Additionally, the male gonadal soma cells did not alter to female function during the male-to-female sex change in the AI/MT-terminated fish. After MT termination in the male-to-female sex-changed fish, the differentiated male germ cells showed increased proliferating activities together with dormancy and did not show characteristics of both sexes in the early germ cells. In conclusion, these findings indicate for the first time in a single species that the mechanism involved in the replacement of soma cells is different between the female-to-male and male-to-female sex change processes in grouper. These results also demonstrate that sexual fate determination (secondary sex determination) is regulated by endogenous sex steroid levels.

Efficacy and safety of nucleoside analogs on blocking father-to-infant vertical transmission of hepatitis B virus.

The aim of the present study was to observe the efficacy and safety of nucleoside analogs in inhibiting father-to-infant vertical transmission of hepatitis B virus (HBV). Nucleoside analogs compete with HBV DNA polymerase substrate to inhibit DNA polymerase, thus preventing the replication of HBV DNA. A case group and control group were recruited for the study. Between March 2006 and March 2012 at the Liver Disease Center of Qinhuangdao Third Hospital, a total of 201 couples were recruited for the case group. In each case, the father tested positive the following HBV markers: Hepatitis B surface antigen (HBsAg), hepatitis B e antigen (HBeAg), antibodies against the hepatitis B core antigen (anti-HBc) and HBV DNA. In total, 189 male patients presented with abnormal liver function (94.0%; 189/201). Prior to pregnancy, all the males in the case group were required to test negative for HBV DNA and exhibit normal liver function, while the females were required to test positive for antibodies against HBsAg (anti-HBs). In total, 188 couples comprised the control group. The couples were recruited between March 2006 and March 2012 in the Prenatal Clinic of Qinhuangdao Women's and Children's Hospital. The fathers tested positive for HBsAg, HBeAg, anti-HBc and HBV DNA. With regard to the females, HBsAg tests were all negative and anti-HBs tests were positive. In the case group, there were no HBsAg-positive or HBV DNA-positive newborns, while anti-HBs tests were all positive; thus, the father-to-infant HBV vertical transmission was successfully inhibited. In the control group, 147/188 newborns tested positive for anti-HBs at birth, accounting for 78.2%. In addition, 28 newborns were positive for HBV DNA (14.9%), and 19 newborns tested positive for HBsAg (10.1%). Statistically significant differences were observed between the two groups with regard to these parameters. However, no statistically significant differences in gestational age, birth weight, birth height, 1- and 8-min Apgar scores, presence of jaundice, other internal and surgical diseases, delivery mode and other birth information were observed when comparing the case group with the control group. Furthermore, there were no fetal malformations or stillbirths in the two groups. In the HBV DNA-positive fathers prior to pregnancy, antiretroviral therapy resulted in a reduced virus load. Therefore, blocking father-to-infant HBV vertical transmission maximally was important. The use of antiviral nucleoside analogs prior to pregnancy was shown to be safe. When the benefits outweighed the risks, the fathers who wanted to have a child continued to use antiviral therapy. However, the sample size of the present study was small, and an increased number of cases and longer follow-up times are required. In addition, the use of nucleoside analogs requires further in-depth assessment from the point of view of prenatal and postnatal care.

The Potential Role of Amh to Prevent Ectopic Female Development in Testicular Tissue of the Protandrous Black Porgy, Acanthopagrus schlegelii.

In most vertebrates, hermaphroditism results in infertility. However, hermaphroditism occurs in 6% of teleosts, which primarily undergo protogyny. Here, to elucidate the transient stage from gonochorism to hermaphroditism, juvenile black porgies as a model animal were fed a diet containing estradiol (E2) for 3 mo, followed by withdrawal of E2 treatment. The E2-terminated fish had ectopically located oocytes in the regenerated testes. Antimüllerian hormone (amh) was strongly expressed in the Sertoli cells with type A spermatogonia and follicle cells with vitellogenic oocytes. Amh was robustly expressed in the ectopic oocytes-bordering region of regenerated testes and in testes with nonsynchronous spermatogenesis. This Amh was released by Sertoli cells and aggregated in the area containing type A spermatogonia in the ectopic oocytes-bordering region. Our in vitro results show that exogenous recombinant Amh (rAmh) can inhibit type A spermatogonia proliferation in the testis but not oogonia proliferation in the ovary. We suggest that Amh-arrested spermatogonia A may act as a boundary to block intercellular communication (i.e., prevent peptide factors released from female tissue to alter the sexual fate of type A spermatogonia) and further inhibit female growth. These results suggest that black porgy can prevent ectopic female growth in the testis and maintain male function of the digonic gonad (testes and ovary separated by the connective tissue) through Amh action. This function of amh might shed light on why the majority of syngonic fish undergo protogyny (female-to-male sex change).

The RDE-10/RDE-11 complex triggers RNAi-induced mRNA degradation by association with target mRNA in C. elegans.

The molecular mechanisms for target mRNA degradation in Caenorhabditis elegans undergoing RNAi are not fully understood. Using a combination of genetic, proteomic, and biochemical approaches, we report a divergent RDE-10/RDE-11 complex that is required for RNAi in C. elegans. Genetic analysis indicates that the RDE-10/RDE-11 complex acts in parallel to nuclear RNAi. Association of the complex with target mRNA is dependent on RDE-1 but not RRF-1, suggesting that target mRNA recognition depends on primary but not secondary siRNA. Furthermore, RDE-11 is required for mRNA degradation subsequent to target engagement. Deep sequencing reveals a fivefold decrease in secondary siRNA abundance in rde-10 and rde-11 mutant animals, while primary siRNA and microRNA biogenesis is normal. Therefore, the RDE-10/RDE-11 complex is critical for amplifying the exogenous RNAi response. Our work uncovers an essential output of the RNAi pathway in C. elegans.

Fabrication of n-type mesoporous silicon nanowires by one-step etching.

In general, n-type mesoporous silicon nanowires (mp-SiNWs) are exclusively created by the two-step metal-assisted chemical etching (MACE). This work first reports that one-step MACE (in HF and AgNO3) is also capable of producing the n-type mp-SiNWs, and the developed formula is generally adapted to generate SiNWs by etching n-Si(100) with electrical resistivity over a range of 10(-3)-10(1) Ω·cm. Integrating the contribution of silicon intrinsic properties in the existing MACE mechanism explicitly accounts for the new findings and contradictions with previous studies. The as-generated mesoporous structures emit red light under laser excitation at room temperature. The red-color emission sensitively varies with temperature over a range of 16-300 K, attributed to a temperature-dependent photoluminescent mechanism.

Enhanced sensitivities for the searches of neutrino magnetic moments through atomic ionization.

A new detection channel on atomic ionization for possible neutrino electromagnetic interactions is identified and studied. Significant sensitivity enhancement is demonstrated when the energy transfer to the target is of the atomic-transition scale. The interaction cross section induced by neutrino magnetic moments (µ(ν)) is evaluated with the equivalent photon method. A new limit of µ(ν)(ν[over ¯](e))<1.3×10(-11) µ(B) at 90% confidence level is derived by using current reactor neutrino data. Potential reaches for future experiments are explored. Experiments with sub-keV sensitivities can probe µ(ν) to 10(-13) µ(B). Positive observations of µ(ν) in this range would imply that neutrinos are Majorana particles.